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1
Åberg, Erik. "Konstruktion av servostyrd press för stansning." Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-182678.
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Detta examensarbete utfördes mot SVIA 2012. Viss information i denna rapport och företagspresentation gäller inte idag. Bland annat blev SVIA uppköpta av ABB 2016 och deras produkter ingår nu i ABBs utbud. Vissa justeringar av företagspresentationen har därför behövts göras men de mesta av informationen från 2012 som gått att behålla är kvar. Den löpande texten i rapporten är skriven utifrån hur det såg ut vid genomförandet. Detta behövs ha i åtanke när man läser igenom rapporten. Detta arbete genomfördes mot företaget SVIA. SVIA hade fått efterfrågat från en tidigare kund att undersöka möjligheterna att leverera en servostyrd press till en av deras produktionsceller. Syftet var att designa ett koncept för denna press samt rita upp en modell i CAD. Kraven på pressen var att den skulle uppnå en presskraft på 20 kN, vara driven av en servomotor samt ha en höjdjusteringsfunktion för att kunna passa in deras olika stansverktyg. Pressen skulle också vara åtkomlig både framifrån och bakifrån för att kunna utföra nödvändiga arbeten på pressen. Innan det praktiska designarbetet började med pressen genomfördes en självstudie för att undersöka olika grundkoncept på pressar. Arbetet genomfördes sedan i största del med CAD, närmare bestämt programmet Creo. Under arbetet genomfördes dessutom hållfasthetsberäkningar som stöd till designen. Arbetet resulterade i ett nytt designkoncept och komplett modell på pressen, som ansågs klara av kraven från kunden. Däremot, för att slutligen kunna verifiera pressen samt nå produktionsnivå behövde tester genomföras på prototyp, möjligen också iterera designen.This work was performed towards a company called SVIA. SVIA had been approached by a former customer to explore the possibilities to deliver a servo powered press machine to one of their production cells. The purpose was to design a concept and also draw a CAD model of the press. The demands for the press were that it had to achieve a pressing force of 20 kN, had to be powered by a servo motor and have a height adjustment feature to be able to accommodate the customer’s different tools. Moreover, the press had to be accessible from both the front and back to be able to facilitate exchanging the tools. Prior to the actual design work, a literature study was conducted to investigate different basic concepts of press machines. Then the new press was developed, predominantly using computer-aided design (CAD). To support the design process, various strength calculations were performed. The work resulted in a new design concept and complete model of the press, which fulfills the requirements set by the costumer. However, to further validate the press design and reach production state, a prototype would have to be constructed and thoroughly tested, possibly iterate the design.
2
Jain, Neera S. B. Massachusetts Institute of Technology, and Somin Lee. "Peanut oil press for developing countries." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36750.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.Includes bibliographical references (leaves 34-35).
Despite the problems with obesity that the United States is facing today, malnutrition, caused in part by severely low dietary fat consumption, remains a problem among many people living in Sub-Saharan Africa. According to the World Health Organization, one third of people in developing countries are malnourished as well as vitamin or mineral deficient. While villagers do not have access to commercially produced vegetable oil (a common source of dietary fat), nor are industrial scale oil extraction methods appropriate for small scale production. As a result, they turn to traditional methods, such as a mortar and pestle, to extract oil from peanuts, sunflower seeds, and other oil bearing seeds and nuts. This process is both time and labor intensive, and still does not yield sufficient amounts of oil to satisfy the need for it. The need for a small scale press is clear. This thesis introduces a simple design which achieves a yield of 46.9 mL per cup (U.S.) which matches the yield produced using industrial technologies. This corresponds to 153% increase in yield and 38.5% increase in rate over using traditional methods such as a mortar and pestle. The design consists of two fixed plates connected by four rods, with a third plate which slides along the four guide rods.
(cont.) A standard scissor jack is the mechanism by which the necessary pressure of 800-1000 psi is generated to extract the oil. A peanut container with a removable bottom holds the peanuts as they are pressed, and holes drilled into its cylindrical face allow the oil to spill out into a collection dish underneath the container. The entire design is compact, with a footprint of one square foot and a height of 22 inches. This is 12 times smaller than the Beilenberg ram press, the standard for small scale presses currently used in developing countries. Experimental results of the loading profile as function of time show that the jack does not need to be turned continuously once the oil begins to appear. This requires significantly less strength than current methods of oil extraction. Although future work is recommended to further develop and improve the press, it shows promise of alleviating the need for such a device in many impoverished parts of the world.
by Neera Jain and Somin Lee.
S.B.
3
Lee, Daipan. "Peanut oil press redesign for Developing countries." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40491.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.Includes bibliographical references (p. 28-29).
One of the causes of malnutrition among the rural inhabitants of Sub-Saharan Africa is the high cost of dietary fats that are necessary to maintain normal body functions. Though the Food and Agriculture Organization of the UN recommends an annual intake of 9.6 liters of dietary fats a year per person, some areas of Africa consume only about 1.5 liters annually. Many members of these communities lack the resources to purchase imported edible oils; locally produced peanut oil would provide a cheaper alternative. In addition, peanut production is particularly beneficial to farmers, as peanut plants enrich the soil they grow in. Once they have a steady supply of peanuts, the problem facing farmers is the inability to efficiently extract the oil from the nuts. The current design for human-powered rapid extraction is the Bielenberg ram press, which uses a lever to generate the required pressure needed to extract the oil. However, this design is not optimal for two reasons: it requires significant upper body strength to operate, and also, incorrect operation of the lever leads to only a fraction of the peanuts' oil content being extracted. For these reasons, this thesis focuses on a design modification originally proposed by a team in D-Lab Spring 2006.
(cont.) While the oil extracting mechanism was kept intact, the lever was replaced by a cam-and-follower system driven by treadles. By moving the driving motion from the upper body to the lower body of the user, the new design aims to address the ergonomics issue present in the Bielenberg ram press. The cam also allows optimization of the pressure profile for the peanuts. Research performed by Ravi Patel in 2007 has shown that a rapid buildup followed by a long period of followed by a gradual advancing of the piston will create the desired pressure characteristics to maximize output. An earlier attempt to convert the Bielenberg ram press into a treadle design yielded several insights into how the design could be improved. These insights have led to many design modifications, which are incorporated into the proposed redesign. This redesign is aimed at improving performance, reducing cost, and increasing the manufacturability of the press.
by Daipan Lee.
S.B.
4
Patel, Ravi M. (Ravi Mahendra). "Maximum of oil output of a treadle-powered peanut oil press." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40465.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.Includes bibliographical references (leaves 32-33).
The manual processing of food products has become a substantial part of the daily routine of a typical household in the developing world. Consumption of oil is an essential part of an individual's diet and thus, the production of oil is an essential activity. In many communities, this oil is obtained by manually pressing it from peanuts. In order to more efficiently and easily express oil from peanuts, a design for a treadle-powered peanut oil press was created. My thesis work will attempt to further increase the amount of oil extracted by optimizing the design of this peanut oil press. The press transfers the motion of the treadle to the horizontal motion of a piston that presses the peanuts via a rotating cam. The focus of this thesis will be optimizing the design of the cam with respect to oil yield. The shape of the cam determines the displacement profile of the piston's compression of the peanuts. I will determine the optimal profile by designing and performing experiments on a variety of different displacement profiles and measuring the amount of oil extracted from the pressed peanuts. The results of these experiments will then determine the optimal cam design.
by Ravi M. Patel.
S.B.
5
Slowe, Thomas J. (Thomas John) 1982. "Design of a prototyping press for 3-d monolithic compliant mechanisms." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32787.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references (p. 38).
The Precision Systems Design and Manufacturing Lab at the Massachusetts Institute of Technology has the need for a metal forming device capable of applying a plastic deformation to two-dimensional sheet metal templates of up to 1/8-inch thickness and 8-inch diameter in order to transform them into prototype three-dimensional monolithic compliant mechanisms. These mechanisms have applications in industrial positioning as they are highly accurate and free from normal performance reducers such as friction, wear, and backlash. This thesis presents the design of a prototyping press capable of achieving the deformation required to produce the 3DMCMs from their 2D templates. The prototyping press that is developed herein utilizes a multiple-piston, hydropneumatic cylinder to deliver up to 5,000 lbf over a 4-inch stroke. The press offers force sensing to within 10%, displacement sensing to within 0.005 inches, and rate control centered around a 6-inch per minute average rate. It is powered by a compressed air supply at up to 100 psi and motion is controlled by a single electrical solenoid shut-off valve.
by Thomas J. Slowe.
S.B.
6
Sabelli, Alessandra Maria 1976. "Design of a press for oil extraction from moringa seeds for Haiti." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32783.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references (leaf 27).
The project here presented focuses on the development of a harvesting tool for Haiti, a developing country, for the extraction of oil from the seeds of the moringa trees. Moringas have an extraordinarily nutritional potential that can help, at least short-term, to solve problems associated with poor nutrition in the area. Furthermore, moringas naturally prosper in Haiti, making it an accessible and inexpensive resource. A first design is presented in this thesis along with the relevant experimentation and results, and progressive development of possible designs. One of the major concerns regarding the extraction process has been the reabsorption of the oil due to the elastic property of the seeds. This factor is important because a significant percentage of the oil extracted can potentially be reabsorbed, consequently limiting the efficiency of the extraction process. I consequently selected a continuous system that could better ensure a constant pressure, which seems desirable. Moreover, inevitably the design is a compromise between efficiency and cost. Therefore, it was necessary to select a design that could be cheaply produced, limiting also the necessity to produce the whole design from scratch. The final design consists of a meat grinder that ends with a cage shaped as section of a cone, the whole being powered by human pedaling. Fresh seeds are inserted in a cone-shaped feeder, while the cake flows out the smaller end of the cage and oil is collected in a container. This project represents a first step into the development of an extraction tool that maximizes the extraction of oil from moringa seeds, and consequently the consumption of the seeds themselves, not exploited so far.
by Alessandra Maria Sabelli.
S.B.
7
Truslow, Samuel B. (Samuel Blagden) 1972. "Permanent press, no wrinkles : reinforced double diaphragm forming of advanced thermoset composites." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9057.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000.Includes bibliographical references (leaf 105).
Structures made out of advanced composite materials have significant advantages over those made from metals. The chief advantages are high strength-to-weight ratio, the ability to tailor mechanical properties, high fatigue resistance and good corrosion resistance. The manufacturing methods used to produce these materials are different from those used to produce metal parts. Composite structures are made from numerous layers of fibrous material which must be prevented from wrinkling during manufacturing to maintain optimal mechanical properties. Manufacturing composite parts without wrinkling can be very difficult when the part has double curvature. In these cases there will be a tendency for the parts to wrinkle as they are shaped. Due to these difficulties many parts are made by hand. This method carries two penalties in that is much slower, and therefore more expensive, than automatic methods and it involves significant hand manipulation of the material resulting in the potential for serious repetitive stress injuries in the workers. The double diaphragm forming process was developed to allow parts of significant double curvature to be made faster and with little hand work. The process involves creating a flat stack of all the layers of material and then forming it into shape between two rubber diaphragms in one step. This process was adapted to a family of structural composite parts, called rib chords, in the Boeing 777 airliner vertical fin and horizontal stabilizer. These parts have considerable double curvature and so present opportunities for large improvements in production rate and ergonomic suitability. Development of a reinforced version of double diaphragm forming has created significant cost savings for manufacturing these parts. A production machine was designed and built to match this process to the production environment for the rib chords. Use of the machine reduces the part flow time by 70% (Boeing's figure) which translates to significant direct cost savings. The process also reduces the potential for worker injuries dramatically. Not only is the processing improved but significant factory floor space and fabricating equipment are freed up since the one machine can make production quantities easily. Finally the process is very well suited for use in an automated production system creating the opportunity for even more savings in the future.
by Samuel B. Truslow.
S.M.
8
Robinson, Robert Eric. "Design of an automated variable configuration die and press for sheet metal forming." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/14922.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1987.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING
Bibliography: leaves 132-133.
by Robert Eric Robinson.
M.S.
9
Tacoronte, Lisa Cristina. "Putting the press to the test : effects of temperature on Shea nut oil output." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/60205.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 52).
In northern Ghana, part of a belt reaching from Sub-Saharan Africa to northern Uganda, women collect and process Shea nuts for their valuable oil. This oil is then used in various cosmetic, cooking, and medicinal products. However, the traditional process to extract oil from Shea kernels is time and labor intensive, and the quality is inconsistent, preventing it from being a primary source of income. In order to address these problems, a hydraulic jack press for extracting Shea oil was designed for a woman's co-operative in the village of New Longoro during the summer of 2009 as part of the International Development Design Summit. This thesis presents the results of a study of the effect of temperature and roasting on the Shea oil yield of a hydraulic jack press in order to evaluate its practicality. Extraction efficiency was measured for ground Shea kernels, either unroasted or roasted, for pressing temperatures ranging from 50-70*C. It was found that a pressing temperature of 60-62°C produced the highest oil yields for both roasted and unroasted nuts, with unroasted, ground kernels producing slightly more oil than roasted, ground kernels. The highest yield produced was (23 ± 2.8)% for unroasted Shea kernels at 60.7°C. Furthermore, it was observed that the optimal press chamber configuration is one with perforations along the circumference of the cylinder and on the base with slits to allow oil to escape. It was also confirmed that post-press filtering will be necessary to purify the oil for marketability. Finally, although the initial results are promising, more investigation is needed in order to determine the economic viability of using the hydraulic jack press.
by Lisa Cristina Tacoronte.
S.B.
10
Effrece, Jr Frank. "The dynamic controls of a hydraulic press by controlling the pump motor." Ohio University / OhioLINK, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1183044178.
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Palsson, Einar, and Mårten Hansson. "Press Measurements and Virtual Rework of Stamping Dies." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-14918.
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Stamping dies are used in the Sheet Metal Forming (SMF) process for manufacturing of car body parts. The lead time for design and manufacturing of a stamping die is long, and therefore costly. In the final step of the manufacturing process, manual rework is performed to reach a desired pressure distribution on the forming surfaces in order to achieve a robust process and an approved part within tolerance. The main purpose for this work is to study and further develop a Virtual Rework Method that alters the shape of the forming surfaces of a die to compensate for the displacements of a stamping press that occur during stamping. Measurements were performed to obtain the displacements that occur in the stamping press during stamping. These measurements were performed on a double action deep drawing press of the brand Danly, located at Volvo Cars Tool & Die department in Olofström, Sweden. The measurement yields information of how the stamping press is deflecting and deforming during operation. The measurements are recorded with a Digital Image Correlation (DIC) system that records the displacements of the press during stamping. The displacements obtained in the measurements are then used as constraints to inverse FE- model a press table with topology optimization. This optimized press table is used in the Virtual Rework Method to be able to simulate both the deformations of the press and the internal deformations that occur in the die. Pre-simulations were performed before the measurements to ensure that the blank holder plate used in the measurements would withstand the applied blank holder force. These simulations also yield if the displacements were large enough for the ARAMIS DIC system to capture. The FE-model used in this work consisted of a die, blank holder, blank holder plate, outer ram and the optimized press table. The Virtual Rework Method was applied on the FE-model, where the result concludes that the altered shape of the deformed forming surfaces is almost identical to the shape of the nominal forming surfaces. However, an inversed modelled structure that represents the behavior of the outer ram is required to apply the Virtual Rework Method on the blank holder. This inversed modelled structure could be created from the displacements obtained in the measurements. To apply the Virtual Rework method on the punch, further measurements are required, where the position of the ARAMIS DIC system is altered, or an additional ARAMIS DIC system is used.Pressverktyg används i plåtformningsprocessen vid tillverkning av karossdelar. Ledtiden för konstruktion och tillverkning av ett pressverktyg är lång och därför kostsam. I det sista steget i tillverkningsprocessen utförs manuell bearbetning för att nå en önskad tryckfördelning på formningsytorna, vilket ger en robust process och en godkänd del inom toleranserna. Huvudsyftet med detta arbetet är att studera och vidareutveckla en virtuell fläckningsmetod som korrigerar formningsytorna på dynan för att kompensera för de förskjutningar som uppstår i en stämplingspress under stämpling. Mätningar har utfördes för att erhålla förskjutning som uppstår i en stämplingspress under stämpling. Dessa mätningar utfördes på en dubbelverkande djupdragningspress av märket Danly, som finns hos Volvo Cars Tool & Die avdelning i Olofström, Sverige. Mätningen gav information om hur pressen deformeras under stämpling. Mätningarna registreras med ett Digital Image Correlation (DIC) system som registrerar pressens förskjutningar under stämpling. Förskjutningarna som erhållits i mätningarna användes sedan som randvillkor för en inversmodell för topologioptimering av ett pressbord. Detta optimerade pressbord används sedan i den Virtuella fläckningsmetoden för att kunna simulera både pressens stelkroppsrörelse och de interna deformationer som uppstår i pressverktyget. En förstudie utfördes innan mätningarna för att säkerställa att den plåthållarplattan som användes i mätningarna skulle motstå den applicerade plåthållarkraften. Denna förstudie gjordes även för att säkerhetsställa att förskjutningarna som uppstår i plåthållarplattan var stora nog för att ARAMIS DIC systemet skulle registrera dem. FE-modellerna som användes i detta arbete bestod av en dyna, plåthållare, plåthållarplatta, yttre slid och det optimerade pressbordet. Den Virtuella fläckningsmetoden applicerades på FE- modellen, där resultatet gav slutsatsen att den korrigerade formningsytan med applicerad belastning är nästintill identisk med formen på den nominella formningsytan. En inversmodellerad struktur som representerar beteendet hos den yttre sliden krävs emellertid för att tillämpa den Virtuella fläckningsmetoden på plåthållaren. Denna inversmodellerade struktur kunde erhållas från de förskjutning som erhölls i mätningarna. För att tillämpa den Virtuella fläckningsmetoden på stansen krävs ytterligare mätningar, där ARAMIS DIC systemets position ändras eller ett ytterligare ARAMIS DIC system används.
Reduced Lead Time through Advanced Die Structure Analysis - Vinnova
12
Mercado-Corujo, Hernán. "A study of the thermo-mechanical reliability of plated-through-hole/press-pin assemblies." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/16033.
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Souke, Chad C. (Chad Conway) 1976. "Development and implementation of setup time reduction strategies for a 700-ton Danley progressive die press." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9356.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1999.Setup time reduction is one of the principle forces enabling lean manufacturing. This thesis documents the formulation and reduction to practice of two stages of a setup time reduction strategy for a 700-ton Danley progressive die press. Common methodologies of setup time reduction were presented and discussed, with the purpose of developing a general algebra for setup reduction. The algebra was applied to develop a specific strategy for setup time reduction of a 700-ton Danley progressive die press. Attempts were then made to reduce the strategy to practice.
by Chad C. Souke.
S.B.
14
Nelson, Alexandra T. "Press fit design : force and torque testing of steel dowel pins in brass and nylon samples." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/36722.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, February 2006.Includes bibliographical references.
An experimental study was conducted to determine the accuracy of current press fit theory when applied to press fit design. Brass and nylon hex samples were press fitted with hardened steel dowel pins. Press fit force and torque required to induce slipping were measured experimentally. Sample dimensions and material properties were utilized to predict expected force and torque levels, which were then measured experimentally. Brass press fit forces proved difficult to predict due to plowing effects in tight interference press fits where material yielding was observed. However, once vertical force was removed, torque was applied to each sample. The observed torque values matched press fit theory well suggesting that the interface pressure of the press fit can be accurately predicted by theory. The brass torque samples matched theory well once material yield conditions were taken into account. The creep sensitivity of the nylon samples made predictions over the testing period unreliable. Results show the need for further testing with specific attention to precision in sample machining and measurements. Other considerations include press fit interface roughness and plowing effects during press fitting.
by Alexandra T. Nelson.
S.B.
15
Lopez, David M. "Development of a pressurized low-temperature tablet press for a carbon dioxide flash frozen ice confection." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/55272.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 122-124).
This document details the conception, design, and testing of a series of prototype powder-pelletizing devices for use with an ice confection powder produced using a CO2 spray freezing process. The device must function at a temperature of 233 K and at pressures of up to 12 bar(a) and must produce at least 500 pellets for use in consumer testing. Design considerations include stress analysis for critical parts, minimization of powder flow path length, formulation of requirements of thermal management system, implementation of the powder compression methods, examination of various agitation methods, and the testing of the prototype apparatus. Trials proved the concept sound as several dozen pellets could be produced using the final prototype. However, ensuring sufficient powder flow for the consistent and continuous production of full-sized pellets is the key difficulty in the implementation of this device. As such, further work should be devoted toward understanding and quantifying the flow properties of the CO2 flash freezing powder.
by David M. Lopez.
S.M.
16
Čupr, Pavel. "Klikový lis 250 s přímým pohonem." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241693.
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This thesis deals with the design of the single point crank press with direct drive. This crank press has an O-shaped stand and an access to the workspace from two sides. The introductory part of this paper describes the principles of mechanical presses drives, drives arrangement presses with direct drive and some conceptual solution stands. The main part of this work is a calculation of basic drive parameters of the press. There are suggested three design variants. The design with the smallest space requirements and good accessibility to the press working space was chosen. The calculation of the main shaft, the input shaft to the planetary gearing and calculation of brake sizes and the planetary gear to the bend and tough was done. Part of this thesis also includes technical drawing of the assembly press, technical drawing of the drive press, technical drawing of the stand a technical drawing of the satelitte gearwheel.
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Kolbábek, Lukáš. "Lis LKDS 800." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230292.
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The present Master´s thesis deals with the concept of press drive of Blanking press LKDS 800 used for blanking in automatic blanking line. The first part of the thesis is dedicated to the individual arrangements of press drives and servo press drives and to the description of main components. The second part of this thesis deals with the structural design of the drive. Based on the computation of the crank mechanism, several design solutions were suggested. From these solutions, the option with the lowest drive height is selected. This option, offers the computation of the main drive, flywheel, spur gearing and clutch/brake combination. This computation is followed by computations of individual construction nodes, which include a design and dimensioning of the individual joggles, shafts and bearings. The drawing of the press and clutch shaft assemblies with a list of items are also included.
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Bicer, Gokhan. "Experimental And Numerical Analysis Of Compression On A Forging Press." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612155/index.pdf.
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Forging is a metal forming process which involves non-linear deformations. Finite element and finite volume software programs are commonly used to simulate the process. In these simulations, material properties are required. However, stress-strain relations of the materials at some elevated temperatures are not available in the material libraries of the related software programs. In this study, the stress-strain curves have been obtained by applying the Cook and Larke Simple Compression Test to AISI 1045 steel at several temperatures on a forging press with a capacity of 1000 tons. The stress-strain curves have also been determined by simulating the processes in a commercial finite element software. It is observed that experimental results are consistent with the numerical ones. A modular die set has been designed and manufactured to conduct the Cook and Larke Simple Compression Test. It has been shown that the forging press with data acquisition system can be used as a material testing equipment to obtain stress-strain curves.
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Bergström, Mikael. "Product Development and Finite Element Analysis of Polyurethane Press Shoe : Produktutveckling och finit element analys av press-sko i polyuretan." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-85657.
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The press-section of a paper machine holds several different types of press rolls. One of the many press roll variants is the Valmet produced press roll, ViscoNip. This press roll utilizes an extended nip in order to increase the amount of water removed. The extended press nip in ViscoNip is special since it is controllable by a pressurized polyurethane press shoe. The press shoe runs through the body of the press roll. Due to limits of the current production process, new manufacturing methods and construction solutions are needed. In cooperation with another thesis, the current design and manufacturing process was reviewed and a plan intended to improve the current solution was formulated. The plan was to, by working together in a project, perform a product development process intended to create concepts able to utilize new methods of manufacturing. By using established methods of concept generation, such as Brainwriting 6-3-5, 11 concepts were created. Some of these concepts involved a redesign of the press shoe, leading to a need for construction and performance analysis. With the other thesis focusing on researching new possible and available manufacturing solutions. The work of this thesis fully committed to the structural and mechanical performance evaluation of the new concepts. This was performed by creating a model of the technical application using Finite Element Modelling in ABAQUS. The model included a hyperelastic material model for the polyurethane material as well as cohesive zone modelling to account for partitioning of the part. The model was then used to simulate the different concepts as they were subjected to a challenging load case. The results of which were used as the basis for structural and performance analysis. The analysis showed proof of sufficient structural stability and mechanical performance for all evaluated concepts. Then, in cooperation with the other thesis, a final concept choice was made. All in all, three different redesigned concepts were deemed as having potential for further development. The current solution was also deemed as having potential for future development but only when new manufacturing methods or techniques were considered.
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Linke, George William. "Innovative Design: Design of a Press System and Molds to Produce a Skateboard Deck." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/1399.
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Skateboarding is a passion for many people. Homemade skateboard machinery has been fabricated throughout the country. While the demand for skateboards is steady; there is a steady growth in the homemade skateboard deck market. The desire to create a one of a kind deck that expresses a person's individualism is growing. This applied research and development effort - designing and fabricating a fluid powered press system and 2-part mold assembly for forming glue up laminations for skateboard decks - is an attempt to gain understanding of the different phases of the product design process.
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Egüz, Izzettin Osman. "Hydraulic press construction for fitting the bearings to the housing." Thesis, Växjö University, School of Technology and Design, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-2125.
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This report was written as a result of a Bachelor Degree Project, together with Swepart Transmission AB. The report contains the construction of a hydraulic press for the assembly operation.
The project started with a new construction of a hydraulic press for the bearings’ assembly. The goal within the thesis work was to fit the three bearings to the housing by only one press motion. This operation should be very safety because of the sensitive tolerance at the bearings and housing. Construction of the cylinders, rams and bolster were the most important parts at this project because this parts’ functions are very important for this assembly.
The next step of this thesis was to calculate the hydraulic press components’ parameters and then choose the suitable components. The focus was to choose more useful and reliable components.
The hydraulic press was modeled in the CAD program Solid Works and 2D technical drawing was drawn in the Autocad. The frame material was chosen and the frame was analysised in the Solid Works.
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Tomeček, Ondřej. "Lis s přímým pohonem 8 000 kN." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417780.
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Master thesis is about designing two point mechanical crank press with nominal force 8 000 kN and with variability width of workbench. First part of thesis is focused on present production of two point mechanical presses. In next part is designing of press with two torque motors. This solution provides wide width range of workbench.
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Dvorník, Milan. "Lis LKJP 250." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-402631.
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This Master thesis deals with the design concept of press drive of LKJP 250 press with planetary gearbox. It is a single one-point crank universal press, which is designed for cold-forming operations. The press is used for operate in single stroke mode or continuous operation when engaged in an automatic press line. The first part of the thesis deals with the research in the field of mechanical crank press drives arrangement and kinematic analysis, followed the description of the main parts of the press drive. The second part of the thesis deals with the design of the press drive. The solutions are suggested in several possible options with performing basic calculation. On the basis of the required criteria, the most suitable variant is chosen, for which detailed design and control calculations of individual design nodes of the press drive are performed. Part of this thesis also includes the required technical drawing documentation of the mechanical press.
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Berg, Jonathan. "Further development of manufacturing method for polyurethane shoe press." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-86081.
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The press-section of a paper machine holds several different types of press rolls. One of the many press roll variants is the Valmet produced press roll, ViscoNip. This press roll utilizes an extended nip in order to increase the amount of water removed. The extended press nip in ViscoNip is special since it is controllable by a pressurized polyurethane press shoe. The press shoe runs through the body of the press roll. Due to the limits of the current production process, new manufacturing methods and construction solutions are needed. In cooperation with another thesis, the current design and manufacturing process was reviewed and a plan intended to improve the current solution was formulated. The plan was to, by working together in a project, perform a product development process intended to create concepts able to utilize new methods of manufacturing. By using established methods of concept generation, such as Brainwriting 6-3-5, 11 concepts were created. Some of these concepts involved a redesign of the press shoe, leading to a need for construction and performance analysis. The other thesis focusing on the structural and mechanical performance evaluation of the new concepts. The work of this thesis focusing on researching new possible and available manufacturing solutions. The new concepts were analyzed with new and possible manufacturing methods to fulfill all the requirements. With all data, a document was created and market research was made to get feedback from more knowledgeable in the subject. Moreover, sequence analysis between the concepts with the current and those new manufacturing methods was made to further explain which manufacturing method that could solve the main problem. All in all, one different redesigned concept was deemed as having potential for further development. The current solution was also deemed as having potential for future development but only when new manufacturing methods or techniques were considered.
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Lin, Shun Yuk. "Synthesis and characterization of nano-emulsion for the enhancement of mechanical properties of durable press finishing cotton apparels /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?CENG%202005%20LIN.
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Wallace, Darrell Richard. "A comparative analysis of a conventional versus a computer-assisted technique for identification of mechanical power press hazards." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1141670152.
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Pilthammar, Johan. "Elastic Press and Die Deformations in Sheet Metal Forming Simulations." Licentiate thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-15481.
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Never before has the car industry been as challenging, interesting, and demanding as it is today. New and advanced techniques are being continuously introduced, which has led to increasing competition in an almost ever-expanding car market. As the pace and complexity heightens in the car market, manufacturing processes must advance at an equal speed. An important manufacturing process within the automotive industry, and the focus of this thesis, is sheet metal forming (SMF). Sheet metal forming is used to create door panels, structural beams, and trunk lids, among other parts, by forming sheets of metal in press lines with stamping dies. The SMF process has been simulated for the past couple of decades with finite element (FE) simulations, whereby one can predict factors such as shape, strains, thickness, springback, risk of failure, and wrinkles. A factor that most SMF simulations do not currently include is the die and press elasticity. This factor is handled manually during the die tryout phase, which is often long and expensive. The importance of accurately representing press and die elasticity in SMF simulations is the focus of this research project. The research objective is to achieve virtual tryout and improved production support through SMF simulations that consider elastic die and press deformations. Loading a die with production forces and including the deformations in SMF simulations achieves a reliable result. It is impossible to achieve accurate simulation results without including the die deformations. This thesis also describes numerical methods for optimizing and compensating tool surfaces against press and die deformations. In order for these compensations to be valid, it is imperative to accurately represent dies and presses. A method of measuring and inverse modeling the elasticity of a press table has been developed and is based on digital image correlation (DIC) measurements and structural optimization with FE software. Optimization, structural analysis, and SMF simulations together with experimental measurements have immense potential to improve simulation results and significantly reduce the lead time of stamping dies. Last but not least, improved production support and die design are other areas that can benefit from these tools.Aldrig tidigare har bilindustrin varit så utmanande, intressant och spännande som idag. Ny och avancerad teknik introduceras i en allt snabbare takt vilket leder till ständigt ökande konkurrens på en, nästan ständigt, ökande bilmarknad. Den ständigt ökande komplexiteten ställer även krav på tillverkningsprocesserna. En viktig process, som denna licentiatuppsats fokuserar på, är pressning av plåt. Tillverkningstekniken används för att forma plåtar till dörrpaneler, strukturbalkar, motorhuvar, etc. Plåtar formas med hjälp av pressverktyg monterade i plåtformningspressar. Plåtformningsprocessen simuleras sedan ett par decennium tillbaka med Finita Element (FE) simuleringar. Man kan på så sätt prediktera form, töjningar, tjocklek, återfjädring, rynkor, risk för försträckning och sprickor m.m. En faktor som för tillfället inte inkluderas i näst intill alla plåtformningssimuleringar är elastiska press- och verktygsdeformationer. Detta hanteras istället manuellt under, den oftast långa och dyra, inprovningsfasen. Detta projekt har visat på vikten av att representera press och verktygsdeformationer i plåtformningssimuleringar. Detta demonstreras genom en analys av ett verkligt pressverktyg som belastas med produktionskrafter. Det är inte möjligt att uppnå bra simuleringsresultat utan att inkludera verktygsdeformationer i simuleringsmodellen. Uppsatsen beskriver även numeriska metoder för att optimera och kompensera verktygsytor mot press och verktygsdeformationer. För att dessa kompenseringar ska stämma är det viktigt att man representerar både verktyg och press på ett korrekt sätt. Förslag på en metod för att mäta och inversmodellera pressdeformationer har utvecklats, metoden är baserad på mätningar med DIC-systemet ARAMIS och optimering i FE-mjukvaror. Optimering, strukturanalys, och plåtformningsanalys tillsammans med experimentella mätningar har en stor potential att förbättra plåtformningssimuleringar samt reducera ledtiden för pressverktyg. Sist men inte minst, andra positiva effekter är en enklare och smidigare konstruktionsprocess och förbättrad produktionssupport.
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Billur, Eren. "Fundamentals and Applications of Hot Stamping Technology for Producing Crash-Relevant Automotive Parts." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366243664.
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Hosseini, Moghadam Seyed Mazdak, and Mohamed Alshihabi. "Mechanical behavior of a bio-based composite : influences of production conditions." Thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-57314.
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Some mechanical properties of DuraPulp, a bio-based, bio-degradable composite made from polylactic acid (PLA) and pulp fibers, were determined. Focus was put on the conditions during productions whereby three different press times were studied. Additionally, two different material compositions (PLA to fiber ratios) were used. Uniaxial tensile tests with two different load rates, one and 50 mm/min, were performed. An increase in maximum strength and E-modulus of DuraPulp was observed by increasing the press time, while PLA content decreased the maximum strength and E modulus.
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Poller, Tilo. "Thermal and thermal-mechanical simulation for the prediction of fatigue processes in packages for power semiconductor devices." Doctoral thesis, Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-154320.
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The knowledge about the reliability of power electronics is necessary for the design of converters. Especially for offshore applications it is essential to know, which fatigue processes happen and how the lifetime can be estimated. Numerical simulation is an important tool for the development of power electronic systems. This thesis analyse the thermal and thermal-mechanical behaviour of packages for power semiconductor devices with the help of simulations. One topic is the evaluation of different thermal models. The main focus is on the description of the thermal cross-coupling between the devices and the influence to the lifetime estimation. The power module is a well established package for power semiconductor devices. It will be explained how the heating period of power cycles influences the failure mode of this package type. Additionally, it will evaluated how SiC devices and DAB substrates influence the power cycling capability. The press-pack is in focus for high power applications as the package short-circuits during an electrical failure without external auxiliary systems. However, the knowledge about the power cycling behaviour is currently limited. With the help of simulations this behaviour will be analysed and possible weak points will be also derived. In the end of the work it will be discussed, how the lifetime can be estimated with help of FEM simulationsFür die Entwicklung von Umrichtern ist die Kenntnis über die Zuverlässigkeit der Leistungselektronik ein wichtiges Kernthema. Insbesondere für Offshore-Anwendungen ist das Wissen über die stattfindenden Ermüdungsprozesse und die Abschätzung der zu erwartenden Lebensdauer der Bauteile essentiell. Hierfür hat sich die Simulation als ein wichtiges Werkzeug für die Entwicklung und Lebensdauerbewertung von leistungselektronischen Anlagen etabliert. In der folgenden Arbeit wird das thermische und das thermisch-mechanische Verhalten der Leistungselektronik mittels Simulationen untersucht. Hierzu wird ein Vergleich zwischen verschiedenen thermischen Modellen für Leistungsbauelemente durchgeführt. Schwerpunkt ist die Beschreibung der thermischen Kopplung zwischen den Chips und deren Einfluss auf die Lebensdauerabschätzung. Ein weiterer Schwerpunkt ist das Leistungsmodul, welches sich als ein Standardgehäuse etabliert hat. Dazu wird erklärt, wie die Variation der Einschaltzeit im aktiven Lastwechseltest den Fehlermodus dieses Gehäusetyps beeinflusst. Weiterhin wird untersucht, wie SiC als Leistungshalbleiter und DAB als Substrat die Zuverlässigkeit beein- flusst. Der Press-Pack ist für Hochleistungsapplikationen von hohem Interesse, da dieses Gehäuse im elektrischen Fehlerfall ohne äußere Unterstützung kurzschliesst. Jedoch ist das Wissen über diese Gehäusetechnologie unter aktiven Lastwechselbedingungen sehr limitiert. Mit Hilfe von Simulationen wird dieses Verhalten untersucht und mögliche Schwachpunkte abgeleitet. Am Ende der Arbeit werden Möglichkeiten untersucht, wie Mithilfe von FEM Simulationen die Lebensdauer von Leistungsmodulen evaluiert werden kann
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Poller, Tilo. "Thermal and thermal-mechanical simulation for the prediction of fatigue processes in packages for power semiconductor devices." Doctoral thesis, Universitätsverlag der Technischen Universität Chemnitz, 2014. https://monarch.qucosa.de/id/qucosa%3A20135.
Full textAbstract:
The knowledge about the reliability of power electronics is necessary for the design of converters. Especially for offshore applications it is essential
to know, which fatigue processes happen and how the lifetime can be estimated. Numerical simulation is an important tool for the development
of power electronic systems. This thesis analyse the thermal and thermal-mechanical behaviour of packages for power semiconductor devices with the help of simulations. One topic is the evaluation of different thermal models.
The main focus is on the description of the thermal cross-coupling between the devices and the influence to the lifetime estimation. The power module is a well established package for power semiconductor devices. It will be explained how the heating period of power cycles influences the failure mode of this package type. Additionally, it will evaluated how SiC devices and DAB substrates influence the power cycling capability. The press-pack is in focus for high power applications as the package short-circuits during an electrical failure without external auxiliary systems. However, the knowledge about
the power cycling behaviour is currently limited. With the help of simulations this behaviour will be analysed and possible weak points will be also
derived.
In the end of the work it will be discussed, how the lifetime can be estimated with help of FEM simulations.Für die Entwicklung von Umrichtern ist die Kenntnis über die Zuverlässigkeit der Leistungselektronik ein wichtiges Kernthema. Insbesondere für Offshore-Anwendungen ist das Wissen über die stattfindenden Ermüdungsprozesse und die Abschätzung der zu erwartenden Lebensdauer der Bauteile essentiell. Hierfür hat sich die Simulation als ein wichtiges Werkzeug für die Entwicklung und Lebensdauerbewertung von leistungselektronischen Anlagen etabliert. In der folgenden Arbeit wird das thermische und das thermisch-mechanische Verhalten der Leistungselektronik mittels Simulationen untersucht. Hierzu wird ein Vergleich zwischen verschiedenen thermischen Modellen für Leistungsbauelemente durchgeführt. Schwerpunkt ist die Beschreibung der thermischen Kopplung zwischen den Chips und deren Einfluss auf die Lebensdauerabschätzung. Ein weiterer Schwerpunkt ist das Leistungsmodul, welches sich als ein Standardgehäuse etabliert hat. Dazu wird erklärt, wie die Variation der Einschaltzeit im aktiven Lastwechseltest den Fehlermodus dieses Gehäusetyps beeinflusst. Weiterhin wird untersucht, wie SiC als Leistungshalbleiter und DAB als Substrat die Zuverlässigkeit beein- flusst. Der Press-Pack ist für Hochleistungsapplikationen von hohem Interesse, da dieses Gehäuse im elektrischen Fehlerfall ohne äußere Unterstützung kurzschliesst. Jedoch ist das Wissen über diese Gehäusetechnologie unter aktiven Lastwechselbedingungen sehr limitiert. Mit Hilfe von Simulationen wird dieses Verhalten untersucht und mögliche Schwachpunkte abgeleitet. Am Ende der Arbeit werden Möglichkeiten untersucht, wie Mithilfe von FEM Simulationen die Lebensdauer von Leistungsmodulen evaluiert werden kann.
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Malm, Simon. "Effekter av förpressad granflis för pelleteringsbarheten i en single pellet press." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-65547.
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I en värld med ökande koldioxidhalter i atmosfären och höjd medeltemperatur, råder det inga tvivel om att vi står inför en rad utmaningar för att minska användandet av bland annat fossila bränslen som generar skadliga utsläpp. Det finns många alternativ till oljebaserade bränslen, och ett som har ökat markant de senaste åren är bränslepellets. Bränslepellets är ett träbaserat biobränsle som i sitt kompakta tillstånd erbjuder ett bra värmevärde och är klimatneutralt. För att tillverka pellets måste råmaterialet först termiskt torkas, från en fukthalt på ca 55 % till ca 10 %, vilket i dagsläget kan motsvara upp till en fjärdedel av hela energiåtgången i pelleteringsprocessen. Med den ökade efterfrågan av bränslepellets finns också ökade förutsättningar för energieffektiviseringar i pelletsproduceringen, speciellt i torkningssteget. Drinor AB har tagit fram en avvattningsmaskin av biomaterial som heter CDP, och med den är det möjligt att avvattna biomaterial till ca 30 %, vilket skulle reducera både tiden och energin det tar att termiskt torka materialet. Avvattningen sker under tryck på minst 40 ton, där vattnet mekaniskt pressas ut ur råmaterialet. Hur avvattningen påverkar råmaterialet, speciellt i en pelletframställning, är oklart och syftet med detta arbete var att ta reda på hur pelleteringsegenskaperna påverkas efter pressning med CDP, och om det finns möjligheter att spara energi i malningsdelen i pelleteringsprocessen. Målet med arbetet var att ta reda på hur CDP påverkar pelletskvaliteter i form av hårdhet och densitet, samt om friktionsutvecklingen i pelleteringsmatrisen förändras, genom att framställa pellets ur 3 scenarion. I ett scenario ska en traditionell pelletsframställning liknas, med endast termisk torkning och i de resterande två scenarion implementeras CDP som försteg till den termiska torkningen. I ett av dessa två scenarion mals inte träflisen innan pelletering, för att se om energi kan sparas utan att offra pelletskvalitet. Ett annat mål var att, per scenario, ta reda på vid vilken fukthalts- och temperaturkombination de bästa pelletsen tillverkades med avseende på hög densitet och hårdhet samt låg friktionsutveckling. Resultaten visade att scenariot med CDP som komplement till termisk torkning och utan malningprocess, producerade pellets med högst hårdhet, högst densitet och lägst friktionsutveckling under båda fukthalterna på pelleteringsmaterialet och nästintill samtliga matristemperaturer. Det scenario som hade endast termisk torkning producerade pellets med lägst densitet och hårdhet samt högst friktion under nästan alla temperaturer och fukthalter. När den bästa fukthalts- och temperaturkombinationen togs fram per scenario, så var scenariot med CDP och utan malning bäst. Pellets producerade där hade ökad densitet, nästan tredubblad hårdhet samt mer än halverad friktionsutveckling i pelleteringsmatrisen, jämfört med scenariot som imiterade traditionell pelletsframställning med endast termisk torkning. Skulle det scenariot med CDP och utan malningsprocess implementeras i en verklig industriell skala skulle det innebära stora förutsättningar för ökad produktion av pellets med bättre kvalitet, samt ett minskat energianvändande i form av reducerad termisk torkning och minskat användande av malningsprocessen.In a world with growing carbon dioxide contents in the atmosphere and elevated average temperature, there is no doubt that we are faced with a number of challenges to reduce the use of, among other things, fossil fuels that generate harmful emissions. There are many alternatives to oil-based fuels, and one that has increased markedly in recent years is fuel pellets. Fuel pellets are a wood-based biofuel that, in its compact state, offers a good thermal value and is climate neutral. In order to produce pellets, the raw material must first be thermally dried, from a moisture content of about 55 % to about 10 %, which can currently account for up to at least a quarter of the total energy consumption in the pelleting process. With the increased demand for fuel pellets, there are also increased possibilities for energy efficiency in the pellet production, especially in the drying stage. Drinor AB has developed a biomaterial dewatering machine called CDP, with which it is possible to drain the biomaterial to a moisture content of about 30%, which would reduce both the time and the energy it takes to thermally dry the material. The dewatering pressure is at least 40 tonnes, where the water is mechanically squeezed out of the raw material. How the dewatering affects the raw material, especially in a pellet production, is unclear and the purpose of this work was to find out how the pelleting properties are affected after pressing with CDP and if there is potential for saving energy in the grinding process in the pelleting process. The aim of the work was to find out how CDP affects pellet qualities in terms of hardness and density, and if the friction development in the pelleting dye changes, by making pellets out of 3 scenarios. In one scenario, traditional pellets production should be resembled, with only thermal drying, and in the remaining two scenarios, CDP is implemented as a complement to thermal drying. In one of these two scenarios, the wood chips were not milled before pelleting, to see if energy can be saved without sacrificing pellet quality. Another goal was to determine, by each scenario, what moisture and temperature combination the best pellets were produced with respect to high density and hardness and low friction development. The results showed that the CDP scenario, as a complement to thermal drying and without grinding process, produced the hardest pellets, highest density and lowest friction development during both moisture levels of the pelleting material and almost all die temperatures. The scenario that only had thermal drying produced pellets with the lowest density and hardness, as well as maximum friction under almost all temperatures and moisture levels. When the best moisture and temperature combination was achieved by each scenario, the scenario with CDP and without grinding was the best. Pellets produced there had increased density, almost triple the hardness, and more than half the friction development in the pelleting die, compared to the scenario that imitated traditional pellets production with only thermal drying. Should the scenario with CDP and without grinding process be implemented on a real industrial scale, it would provide great conditions for increased production of better quality pellets, as well as reduced energy use in the form of reduced thermal drying and reduced use of the grinding process.
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Vachek, Jakub. "Lis LKDE 500 s přímým pohonem." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417778.
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The topic of this master thesis is design of the mechanical two-point press with eccentric shaft and direct drive. The thesis contains design and control calculations according to given parameters and also contains drawings of main parts for the press.
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Christensson, Jesper. "Relation Between the Material in Press Hardening Dies and Fully Martensitic Transformation : Sheet properties of thick 3D-sheets in small series production." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-79015.
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This report evaluates the influence of the die material on the cooling rate and martensitic transformation of press hardened sheets. The goal was to increase the thicknesses of sheets that can form fully martensitic microstructure when press hardened. To achieve this, a numerical- and an experimental method was used and results were compared to assess the impact of die material change. The tests were conducted with two die materials, a ductile cast iron according to standard EN‑GJS‑700‑2 and a casted steel according to standard EN 1.6220. Two sheet materials, Hardox400 and Hardox450, were press hardened and two different thicknesses were evaluated. Simulations have been designed with temperature dependent material properties based on data gathered from the literature survey. All simulations indicated an improved cooling rate over the entire temperature spectrum when changing from the iron die to the steel die. An experimental procedure has been performed using two different dies, both planar and of approximately the same thickness. Thermocouples were used to obtain cooling curves of all sheets during quenching. Samples were taken from each sheet and the hardness, microstructure and the present phases were investigated. The experiments concluded that the thinner sheets, when quenched, experienced an overall increase in cooling rate in the steel die compared with the iron die. A total reduction in cooling time by 37.5%-43,7% was observed over the entire temperature span. However, only the Hardox400 sheet fully formed martensite, as the cooling of the Hardox450 sheets still was not fast enough in either of the dies. For the thicker sheets, the experiments also indicated a reduction in total cooling time. The total cooling time was reduced by 23% when pressed in the steel die compared to the iron die. This improvement, however, was not observed at higher temperatures. At the critical temperature span between 800˚C and 500˚C, the sheet showed no improvements in cooling rate with the die material change. Both the hardness measurements and the microstructure evaluation of the thicker sheets indicated a pearlitic-martensitic microstructure. As both the simulations and experiments indicated similar improvements, the increase in cooling rate could be accredited to the die material change. This concludes that the heat transfer properties of the die material affected the cooling characteristics of the process. It was also concluded that the thinner sheets experienced a reduced cooling time over the entire temperature spectrum with the die material change. The thicker sheet, however, only experienced a reduced cooling time in the lower temperature span. Thus, changing the die material did not affect the hardening of the thicker sheets. This ultimately resulted in an unsuccessful attempt to increase the possible thickness of sheets with fully martensite microstructure. The improvements observed for the thinner sheets, are however promising and could be further evaluated for another sheet material.I denna avhandling har relationen mellan ett verktygmaterials kylningseffekt och genomhärdningsförmåga under presshärdning utvärderats, med målet att öka tjockleken på plåtmaterial som genomhärdar. För att åstadkomma detta har en numerisk undersökning och en experimentell undersökning utförts för att bedöma effekten av ett byte av verktygsmaterial. Undersökningarna utfördes med två verktygsmaterial, ett segt gjutjärn enligt standard EN‑GJS‑700‑2 och ett gjutet stål enligt standard EN 1.6220. Under testerna användes även två olika plåtmaterial, Hardox400 och Hardox450, i två olika tjocklekar. Simuleringen har utformats med relevanta temperaturberoende materialparametrar erhållna från teorin. Resultaten från simuleringarna påvisade att ett byte av verktygsmaterial gav snabbare kylning av all plåtar över hela det undersökta temperaturspannet. Den experimentella undersökningen har utförts med två olika pressverktyg, båda plana med likartad tjocklek. Temperaturgivare användes för att erhålla kylkurvor för plåtarna när de kyldes i verktygen. Hårdhet, mikrostruktur och erhållna faser undersöktes för varje plåt. Experimenten påvisade att de tunnare plåtarna kyldes snabbare i stålverktyget än i järnverktyget över hela temperaturspannet, och resulterade i 37,5%-43,7% kortare kyltider. Trots detta, var det endast Hardox400-plåten som genomhärdades, då kylningen av Hardox450-plåten inte var tillräckligt snabb i något av verktygen. Även de tjockare plåtarna uppvisade en totalt kortare kyltid. Kyltiden minskade med 23% i stålverktyget jämfört med järnverktyget. Denna förbättring observerades dock inte över hela temperaturspannet. Vid höga temperaturer kylde stålverktyget långsammare än järnverktyget. De släckta plåtarna erhöll en perlitisk/martensitisk struktur vid komplett svalning, oberoende av verktygsmaterial. Eftersom både simuleringarna och experimenten påvisade liknande förbättringar, kan den ökade kylhastigheten härledas till bytet av verktygsmaterial. Detta fastställer att värmetransportegenskaperna hos verktygsmaterialet hade en inverkan på kylningen i processen. Studien påvisade också att de tunnare plåtarna kyldes fortare över hela temperaturspannet vid materialbytet. De tjockare plåtarna uppvisade dock endast en kortare kyltid i det lägre temperaturspannet. Därmed förblev härdningen av de tjockare plåtarna opåverkad av materialbytet. Detta resulterade i att presshärdning av ökad plåttjocklek för det undersökta materialet inte lyckades. De observerade förbättringarna hos de tunnare plåtarna är dock mycket lovande och bör studeras vidare.
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Hill, Davion M. "Microstructure and mechanical properties of titanium alloys reinforced with titanium boride." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1150402807.
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Humpolíček, František. "Lis LKDS 630." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-382279.
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Final thesis on the design of the drive of a cutting mechanical two-point crank press with a nominal force of 6300 kN. After the theoretical definition of the area of mechanical crank presses and their drives at the beginning of the work, the actual design solution follows. The main idea of the design is the drive arrangement with the concurrent axis of the clutch shaft. The supplied torque is distributed on two longitudinally mounted drive units via a two-sided bevel gear. Solution of the construction design is aimed at enabling workspace variability while simultaneously unifying the maximum number of drive components. Drawing documentation of selected components and assemblies is the part of the thesis.
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Groseclose, Adam Richard. "Forming of AHSS using Servo-Presses." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1408548321.
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Šilkus, Edgaras. "Lapo perdavimo mechanizmo dinaminio tikslumo tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2012~D_20120801_121512-82693.
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Lakštinėse spausdinimo mašinose spausdinant spalvotus atvaizdus svarbu mašinos atskirose sekcijose atspaudų sutapimą išlaikyti šimtųjų milimetro dalių tikslumu. Be to, spausdinamų atvaizdų geometrinis nesutapimas abiejose lapo pusėse neturi viršyti 0,1 mm. Viena iš pagrindinių nesutapimo priežaščių yra mechaninio krumpliaratinio perdavimo mechanizmo iš vienos sekcijos į kitą sukamieji virpesiai, kuriuos sukelia krumpliaračių paklaidos ir pasipriešinimo momentų pokyčiai tarp ofsetinių ir forminių cilindrų. Darbe analiziniu – kompiuteriniu būdu nagrinėjama šių virpesių įtaka lapo perdavimo tikslumui. Konkrečiam tyrimui pasirinkta „Heidelberg“ spausdinimo mašina GTO 52, tačiau darbe taikoma tyrimo metodika tinka ir kitoms mašinoms. Sudarytas elektros pavara valdomo lapų perdavimo mechanizmo dinaminis modelis su 16 laisvės laipsnių. Sistemos matematinis modelis (virpesių lygtys ir struktūrinė schema) sudarytas kompiuterizuotu būdu MATLAB/SIMULINK programų terpėje, kurioje atliktas sistemoje vykstančių dinaminių procesų modeliavimas. Pavaroje kylančios paklaidos apibūdinamos sukamųjų virpesių amplitudinėmis – dažninėmis charakteristikomis. Nagrinėjama šių charakteristikų pobūdžio, rezonansinių virpesių ir jų dažnių įtaka lapo perdavimo paklaidos dydžiui.It is important in printing machines to maintain very high print quality (hundredths of a millimeter) in printing colorful prints. Also mismatches of prints in both sides of sheet must not exceed 0,1 millimeter. One of the reasons of mismatching is mechanical gear transfers mechanisms, from one printing unit to another, rotational oscillations, which are generated by gear errors and resistance moment changes between offset and print cylinder. These oscillations influence to sheet transfer accuracy are examined in analytical – computer way. For particular examination there was selected “Heidelberg” printing press GTO 52, but the examination method can be used for other presses. There was formed dynamic model with 16 degrees of freedom. Mathematical model of the system (oscillation equations and flowchart) was formed with MATLAB/SIMULINK program, in which dynamical process modeling was done. Errors in drive described as an amplitude frequency response. There was examined these response nature, resonant oscillations and its frequency influence to sheets transfer errors size.
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Aktakka, Gulgun. "Analysis Of Warm Forging Process." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607061/index.pdf.
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Forging is a metal forming process commonly used in industry. Forging process is strongly affected by the process temperature. In hot forging process, a wide range of materials can be used and even complex geometries can be formed. However in cold forging, only low carbon steels as ferrous material with simple geometries can be forged and high capacity forging machinery is required.
Warm forging compromise the advantages and disadvantages of hot and cold forging processes. In warm forging process, a product having better tolerances can be produced compared to hot forging process and a large range of materials can be forged compared to cold forging process.
In this study, forging of a particular part which is being produced by hot forging at 1200°C for automotive industry and have been made of 1020 carbon steel, is analyzed by the finite volume analysis software for a temperature range of 850-1200°
C. Experimental study has been conducted for the same temperature range in a forging company. A good agreement for the results has been observed.
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Palnati, Mahendra. "Design, Fabrication and Analysis of a Paver Machine Push Bar Mechanism." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/6007.
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Now-a-days, the major challenge that’s being faced by the concrete industry is the cleaning of concrete handling equipment. Concrete consists of aggregates, which harden with time, and the transportation of concrete mixture within the plant is a significant problem. This will not only increase the overall maintenance cost, but will lead to loss of raw materials, affect the rate of production, and reduce the lifetime of concrete handling equipment.
The present study focuses on the design and implementation of an adaptive cleaning mechanism in the concrete industry and its importance in achieving efficient cleaning, which is tested to verify its performance in the Paver production plant. The goal of this study is to provide practical evidence about the importance of adaptive cleaning mechanisms for industrial applications.
The first chapter gives a detailed introduction about pavers and the production process, the cause of material loss that occurs during transportation of wet concrete mixture inside a paver plant, and its effect on handling equipment and work environment. The second chapter explains design and working of the paver machine push bar mechanism, which can be implemented in a hydraulic press production process of pavers. The third chapter includes analysis and results of the mechanism obtained using Solidworks and Autodesk Inventor followed by observations that are achieved based on practical application of this mechanism in a paver production plant.
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Birnbaum, Peter, Verena Kräusel, and Dirk Landgrebe. "Forming Behavior of Manganese-Boron Steel 22MnB5 while Cooling according to its Microstructural Development." Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-170323.
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The press hardening belongs to state-of-the-art technology at sheet metal forming to gain high strength and crash resistant parts in automotive industry. This process could establish due to its cost- and esourceefficiency. According to ongoing developments on direct press hardening processes it is necessary to describe and understand the thermo-mechanical treatment of 22MnB5. Therefore the flow behavior and phase transformation during cooling with simultaneous forming is investigated. The experimental process considers industrial parameters in order to get industry-oriented results.
In deep drawing processes the sheet metal is roped into the draw die and bended around the die edge. Thereby sheets perform different stages of compressive and tensile strain at the die oriented side and the punch oriented side of the sheet. There are different stages and values of stress and strain according to several layers of the sheet over its cross-section. The values of stress, strain and forming rate were FEcalculated for industry-relevant bending radii and sheet thicknesses of manganese-boron steel 22MnB5. According to the calculations different cooling and forming strategies were performed by dilatometric tests. The forming behavior is described by the microstructural development with regard to the cooling rate and temperature. Beside the influence of austenite forming on the phase transformation and mechanical properties is considered. A prospective view is given to illustrate ongoing examinations under compressive and combined tensional and compressive forces.
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Černych, Konstantin. "Fleksografinės spausdinimo mašinos „OMET VARYFLEX 420 FP“ sekcijos pavaros dinaminio tikslumo tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20060616_103722-39657.
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Master‘s graduation dissertation research object is the drive of one unit of multisection web-fed flexographic printing press „Omet Varyflex 420 FP“. The main purpose of the work is drive’s dynamical precision research, basing on the torsion vibration. But the main attention is concentrated on the research object mathematical model creation. It will be able to investigate torsion vibration. In the beginning there is description of the research object, its dynamical model and assumptions, made while modeling the object. As the main research object is mechanical drive, unit’s electric drive is not detailed. Unit‘s structural model is created using the „MATLAB Simulink“ software. While modeling, it was proved the model is adequate. It was investigated how generalized coordinates and dynamical datums change while the press is switched on and starts to work with constant angular acceleration and when the angular speed reaches particular value, it does not change any more. Amplitude-frequency and phase-frequency responses of some generalized coordinates were got. Changing some parameters flexographic printing plate aging is modeled. It is watched how aging influences torsion vibration. While modeling it was determined how gearwheels cyclic harmonic error’s amplitude and beds resistance coefficients influence dynamical datums. It was also determined unit’s electric drive influence on generalized coordinates frequency responses. Basing on the analysis of the results, the conclusions... [to full text]
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Kulachenko, Artem. "Mechanics of paper webs in printing press applications." Doctoral thesis, Stockholm, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3863.
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Novotný, Lukáš. "Vyjížděcí stůl karosářského lisu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-379005.
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This Master thesis deals with design structures of moving bolster for body panel press and with design of railroad tracks, in which the bolster is moving in two mutually perpendicular directions. These moving bolsters are used for facilitating and speeding up the change of pressing dies, which is desirable in automated automotive industry for shortening and streamlining the pressing die change. The part of the work is research of the current state of knowledge in systems for quick die change, design of the moving bolster and its drive, design of railroad tracks, amount of design and control calculations, design of mechanism for lifting the bolster, optimization and strength calculations of bolster in ANSYS software. All the design structures of bolster, railroad tracks and basic workplace layout are processed in 3D software for modelling Autodesk Inventor. Attachments consist of drawing documentation of main assemblies, namely mounting drawing of moving bolster assembly, mounting drawing of railroad tracks assembly, drawing of workplace layout and furthermore drawing of driven shaft, weldment and workpiece of moving bolster and railroad tracks block.
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Poduška, Libor. "Návrh konstrukčního řešení autoklávu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241853.
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Master thesis deals with general basic design od autoclaves. It deals with the design of an optimal design solution autoclave to set parameters with the design requirement of hermetic doors for loading the workpiece. This solution is analyzed regard to stable pressure vessels. The whole design is processed in parametric SolidWorks software with which they are executed and initial stress analysis of individual designs. Final strength FEM analysis is performed using Ansys. Some proposals are technical-economic evaluation.
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Alkadi, Lubna T. "IPS e.max CAD and IPS e.max Press : fracture mechanics characterization." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/48598.
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Objective: To determine fracture toughness (KIC) and fatigue crack propagation (FCP) parameters for IPS e.max CAD and IPS e.max Press.
Materials and methods: For KIC determinations, 20 (6x6x6x12mm) notchless triangular prism (NTP) specimens of IPS e.max CAD and IPS e.max Press were prepared. IPS e.max CAD blocks were cut, ground and then crystallized, while IPS e.max Press ingots were pressed into molds obtained from wax prisms. Each specimen was mounted into a holder and custom grips were used to attach the holder to a computerized universal testing machine (Instron model 4301). The assembly was loaded in tension at a crosshead speed of 0.1mm/min and KIC was calculated based on the recorded maximum load at fracture. Fractured surfaces were characterized using scanning electron microscopy (SEM). The results were statistically analyzed using Weibull statistics and t-test (⍺=0.05).
For FCP characterization, a pilot test was done with three Plexiglas NTP samples. A pre-crack was initiated in one of the specimen edges. Several lines were scribed on the side of the specimen to monitor crack propagation. The specimens were mounted in the holder and then attached to custom grips on a servo hydraulic fatigue-testing machine (Instron model 8511). A strain gauge was attached to these grips to monitor crack opening displacement. Each specimen was cyclically loaded in tension (Mode I) in a load range between 1 and 20 N and crack length was monitored and filmed using a high definition video recorder (SONY HDR-XR550V) attached to a microscope (Edmund Scientific Co, Barrington, NJ). Video recording was terminated once catastrophic fracture of the specimen occurred. Cyberlink Power Director and Image J software were used in data analysis.
Results: KIC values were significantly higher for IPS e.max Press than IPS e.max CAD. The pilot FCP tests on Plexiglas revealed limitations with regards to the applicability of NTP specimen KIC test to FCP studies due to the presence of a trapezoidal crack front in the specimens.
Conclusion: IPS e.max Press is superior to IPS e.max CAD in KIC. Further research should be conducted to evaluate the feasibility of using a trapezoidal crack front in FCP studies.Dentistry, Faculty of
Graduate
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Åkerström, Paul. "Material characterisation for simulation of press hardening." Licentiate thesis, Luleå, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17533.
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The growing effort to reduce vehicle weight and improve passive safety in the automotive industry has drastically increased the demand for ultra high strength steel components. There exist several production methods for such components, where the press hardening technique (hot stamping) is one of the most successful in producing complex components from boron steel. In order to accurately perform numerical Finite Element (FE) simulations of the actual thermo-mechanical forming, it is crucial to use correct material data and models. This work is focusing on two main aspects of the material characterisation as follows. The first is the flow stress of the austenite at elevated temperatures and different strain rates, relevant for the process, which is crucial for correctly predicting the strains in the component and the forming force. During a press hardening cycle, the actual forming is performed at high temperatures and the steel is in the austenitic state. The second, the austenite decomposition into daughter products such as ferrite, pearlite, bainite or martensite is a function of the thermal and mechanical history. To find the mechanical response (flow stress) for the austenite, a method based on multiple overlapping continuous cooling and compression tests (MOCCCT) in combination with inverse modelling has been developed. A validation test (in combination with the compression tests) shows good agreement with the simulated forming force, indicating that the estimated flow stress as a function of temperature, strain and strain rate is accurate in the actual application. The austenite decomposition model is developed and integrated as a material subroutine into the FE-code LS-DYNA. The model is based on the combined nucleation and growth rate equations proposed by Kirkaldy. A separate test to simulate different cooling histories along a boron alloyed steel sheet has been conducted.Godkänd; 2004; 20070128 (ysko)
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Olsson, Robin. "Utvärdering av hållfasthetstester för singelpellets i relation tillstandardmetoden ISO 17831-1:2015 : En studie kring plastpellets möjligheter att ersätta traditionella träpellets." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-83362.
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Den ökade efterfrågan på pellets har fört med sig högre krav på pelletkvalité och detta har lett till att forskningen i Sverige har övergått från att studera möjliga bränslen till att studera pelletkvalité, ofta med fokus på mekanisk hållfasthet. För att pröva den mekaniska hållfastheten så finns olika standardmetoder såsom tumling enligt ISO 17831-1:2015, som är europeisk standard, och lignotest. Standardmetoderna kräver en större mängd pellets och kan inte användas för att pröva pellets från en singelpelletpress, vilket är ett mycket vanligt sätt att producera nya pelletsammansättningar. En singelpelletpress tillverkar en pellet åt gången och för att prediktera mekaniska hållfastheten finns många olika metoder, till exempel dropp- och hårdhetstest. Det är idag oklart hur väl metoderna för att pröva pellets från en singelpelletpress predikterar mekaniska hållfastheten och det finns en begränsad mängd forskning som undersöker korrelationen med standardmetoderna. Äldre forskning visar på en positiv linjär korrelation medan nyare forskning visar att korrelationen även beror på pelletens sammansättning. Det finns också studier som använder nya sätt att pröva enstaka pellets. En ny studie tumlar pellets tillsammans med plastpellets, men inga jämförelser med andra metoder utförs. En annan studie prövade tumling samt lignotest för en pellet åt gången och jämförde med tumling enligt ISO 17831-1:2015. Den studien visade ett R2 på 0.83 respektive 0.94 för pellets med en mekanisk hållfasthet över 90%. En metod som korrelerar med standardmetoderna skulle mycket tydligare indikera hur en pellet från en singelpelletpress skulle prestera i större produktionsskala. Om metoden även utnyttjar redan tillgänglig teknik finns möjligheten för en bred användning, likt en standardmetod, som skulle underlätta jämförelser mellan olika studier och samarbeten mellan forskningsinstitut. I detta arbete undersöks validiteten av att tumla enstaka pellets tillsammans med plastpellets. Plast- och singelpelletsmixen som innehöll 3, 10 och 20 pellets, resterande del (upp till 500g ±10g) plastpellets, tumlades för 6 olika sorters pellets. Standardavvikelse, relativ standardavvikelse samt medelvärdet av mekaniska hållfastheten bestämdes och den linjära regressionen med tumling enligt ISO 17831-1:2015 undersöktes. För samma pelletsorter genomfördes dropptest och hårdhetstest där den linjära regressionen med tumling enligt ISO 17831-1:2015 även gjordes för hårdhetstestet. Resultaten visar att tumling med plast- och singelpelletmix fungerar som alternativ metod till ISO 17831-1:2015 för pellets med en mekanisk hållfasthet över 92,45%, där mycket tillförlitligt resultat fås för 3 eller fler tumlade pellets över 96,62% mekanisk hållfasthet där 8 av 9 uppmätta standardavvikelser var under 1 %. För hela det prövade kvalitetsintervallet visades en korrelation (R2) med standardmetoden på 0,88-0,98 och ett R2 nära 1 för pellets med en mekanisk hållfasthet över 95 %. Dropptestet gav ingen information om pelletens mekaniska hållfasthet och bedömdes inte som en lämplig metod. Hårdhetstestet visade en hög relativ standardavvikelse mellan 19-40 % och en korrelation (R2) med standardmetoden på 0,78. Tumling med plast- och singelpelletmix hade både lägre standardavvikelse och högre korrelation med standardmetoden som visar att det är en bättre metod för att prediktera mekaniska hållfastheten för enstaka pellets än hårdhetstest.The increased demand of pellets has led to higher demand on pellet quality causing a shift in Swedish research from studying possible fuels to studying pellet quality, often with a focus on mechanical durability. To test the mechanical durability there are various standard methods such as tumbling according to ISO 17831-1:2015, which is the European standard, and lignotest. The standard methods require a large amount of pellets and can´t be used to test pellets from a single-pellets press, a common way to produce new pellet compositions. A single-pellet press produces one pellet at a time and to predict the mechanical durability there are different methods, such as drop and hardness tests. Today it´s unclear how well the methods for testing pellets from a single-pellets press predicts the mechanical durability and there are a limited amount of research that examines the correlation with the standard methods. Earlier research shows a positive linear correlation while a recent publish study showed that the correlation also depends on the composition of the pellet. However, also new ways to test individual pellets has recently bin published, where single pellets were tumbled together with plastic pellets, but no comparisons with other methods were made. Another study tried tumbling and lignotest for one pellet at a time and compared with ISO 17831-1:2015. The study showed an R2 of 0,83 and 0,94 respectively for pellets with a mechanical durability above 90% A method that correlates with the standard methods would indicate how a pellet from a single-pellet press would preform on a larger production scale. If the method also uses already known technology there is the possibility of a broad use, similar to a standard method, wich would facilitate comparisons between different studies and collaborations between research institutes. In this study, the validity of tumbling individual pellets together with plastic pellets is investigated. The plastic and single-pellet mix containing 3, 10 and 20 pellets, the remaining part (up to 500 ±10g) plastic pellets, was tumbled with 6 different types of pellets. Standard deviation, relative standard deviation and the mean value of the mechanical durability were determined and the linear regression with tumbling according to ISO 17831-1:2015 was examined. For the same pellet varieties, drop and hardness tests where preformed, where the linear regression with ISO 17831-1:2015 was also examined for the hardness test. The results show that tumbling with plastic and single-pellet mix works as an alternative method to ISO 17831-1:2015 for pellets with a mechanical durability above 92,45 %, where very reliable results was obtained for 3 or more tumbled pellets above 96.62 % mechanical durability where 8 out of 9 standard deviations measured below 1%. For the entire tested quality range, a correlation (R2) was shown with ISO 17831-1:2015 of 0.88-0.98 and an R2 close to 1 for pellets with a mechanical durability over 95 %. The drop test did not provide any information on the mechanical durability of the pellet and was not considered an appropriate method. The hardness test showed a high relative standard deviation between 19-40 % and a correlation (R2) with ISO 17831-1:2015 of 0.78. Tumbling plastic and single-pellet mix had both lower standard deviation and higher correlation with the standard method ISO 17831-1:2015 which shows that it is the superior method for predicting the mechanical durability of individual pellets over hardness test.
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Boullosa, Allariz Beatriz. "Déshydratation naturelle et mécanisée de sédiments : étude des processus mis en jeu et applications." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC285/document.
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Les opérations de dragage génèrent d’importants volumes de sédiments à teneur en eau élevée qui sont difficilement transportables. Toute opération de valorisation ou stockage des sédiments implique de réduire la teneur en eau. Le séchage naturel et la déshydratation mécanisée des sédiments répondent à cette attente. Le séchage naturel des sédiments est la technique de déshydratation la plus économique et la meilleure du point de vue environnemental. Le temps de séchage peut être réduit par des moyens techniques adaptés (retournement, scarification) mis en action par l'application de critères d’aptitude au séchage naturel. Pour ce faire, le processus de séchage naturel a été reproduit à l’échelle du laboratoire à l’aide d’essais d’Égouttage et de Séchage et d’essais de Séchage et de Retrait couplés à des essais scissométriques. Ils ont porté sur neuf sédiments : sept sédiments de barrage, deux sédiments marins et une kaolinite. Une relation Su=f(IP) a été établie. Cette relation permet d’obtenir la cohésion non drainée Su à partir d’une mesure de teneur en eau. Elle permet aussi de définir ou cerner le moment le plus propice au retournement des sédiments à l’aide d’engins spécifiques sur site. Une autre méthode mécanique pour réduire le temps de séchage est suggérée. Il s'agit de pratiquer une scarification des sédiments à l’aide d’outils mobiles, voire robotisés, comme un rouleau scarificateur ou d'une rangée d'outils transportés par un treillis mobile adapté. En ce qui concerne la déshydratation mécanisée des sédiments, une nouvelle méthode de déshydratation en continu a été proposée à partir d'une presse à boues KDS®. Pour des raisons de conception et d'application, la presse à boues KDS® n’a jamais été utilisée pour déshydrater des sédiments. Un plan expérimental a été développé. Il est démontré que la presse KDS® est capable de déshydrater un sédiment fin sableux sans une maintenance démesurée. Des adaptations de la presse KDS® à la déshydratation de sédiments et des améliorations sont finalement proposéesDredging operations produce large amounts of sediments with high water content, that are difficult to handle. Storage management and future reuses need to reduce the water content of sediments. Natural and mechanical dewatering of sediments meet this need. The most economic and eco-friendly method of dewatering is natural dewatering. Dewatering period can be reduced with suitable technical means such as adapted plough or scarifier for sediments, operating under defined dewatering criteria. The natural dewatering process was investigated and reproduced at the laboratory scale by performing Natural dewatering test and Shrinkage test coupled with shear measurements (vane shear testing). Nine sediments have been considered: seven dam sediments, two marine sediments and a kaolinite clay. A relationship Su = f(IP) has been established. It allows to deduce the undrained shear strength Su from only a measurement of water content. It allows to state on the right moment to put in operation the specific tools for ploughing and returning over or scarifying sediments stored. These tools can move in the sediments (adapted plough) or roll on the sediments (scarifiying roller) or roll on banks of sediment storage basin. Another way to dewater high water content sediments concerns a mechanical device. Thus a new method of continuous dewatering has been investigated using a prototype machine patented and referenced as KDS® sludge press. This type of press was not adapted for dewater sediments. Full of dewatering tests have been undertaken and performed with this prototype concerning some of sediments (see natural dewatering testing) and sandy clayey mixtures. It has been shown that KDS® press is able to dehydrate sediments including fine sandy sediments without excessive maintenance. Some adaptations and improvements of KDS® press to dewatering sediments are finally suggested
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Salomonsson, Per. "Experimental and numerical evaluation of heat transfer in the press hardening process." Licentiate thesis, Luleå : Division of Solid Mechanics, Luleå University of Technology, 2009. http://pure.ltu.se/ws/fbspretrieve/3370099.
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