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Journal articles on the topic 'Dye penetrant inspection'
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1
Abend, Klaus. "Fully automated dye-penetrant inspection of automotive parts." Computer Standards & Interfaces 21, no. 2 (June 1999): 157. http://dx.doi.org/10.1016/s0920-5489(99)92144-x.
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Cicic, Dumitru Titi, Cătălin Gheorghe Amza, Diana Popescu, and Florea Dorel Anania. "Automated Stand for Non-Destructive Testing Evaluation of Metal Products." Applied Mechanics and Materials 371 (August 2013): 401–5. http://dx.doi.org/10.4028/www.scientific.net/amm.371.401.
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Problem be used for evaluating products quality: - Destructive evaluation, in which the product is destroyed in order to analyse its properties and internal structure; - Non destructive evaluation (NDE), used for identifying defect and irregularities, without damaging the product. These non destructive evaluation methods include [1-4]: ‐ Visual and optical testing – VT; ‐ Magnetic particle testing – MT; ‐ Liquid penetrant testing –PT; ‐ Radiographic testing – RT ; ‐ Ultrasounds testing – UT; ‐ Eddy current testing – ET; One of the most frequently used method of non destructive examination is PT or dye penetrant testing (DPT), due to the low costs involved, ease of use and flexibility, suitability to a large number of applications. This method evaluates the presence of open discontinuities (or cracks) on the surface part, based on reverse capillary action and on the developer absorption effect which draw out penetrant and produces indications visible for the inspector (see fig.1 for a principle scheme of LP examination [5]). Although widely used, PT has several disadvantages: - Limitation to surface defects or to the defects which communicates with the surface; - Only products with non porous surfaces (or with low porosity) can be inspected; - Important amount of time used for manipulating the parts during inspection; - Results interpretation heavily depends on subjective aspects such as operator experience, knowledge and motivation. In order to eliminate or reduce the operator involvement in the process steps, research has being made for automating the process, such examples of liquid penetrant inspection lines can be found in [10-15]. However, in all analysed automated PT systems, the inspection is still made visually by an inspector, who gives a pass/fail grade for the inspected parts. The difficulty of fully automating the liquid penetrant inspection process is due not only to the necessity to precisely determine and control process parameters (dwell time, developer time, drying time, quantity of penetrant, developer and cleaning water, pressure for spraying solutions with penetrant, developer and cleaning water, transport speed, etc.) but also to the evaluation and results interpretation process. Thus, even if there are patents [16-17] which present approaches and general frameworks for fully-automated LPT systems, including also automatic image processing of the flaws, to the best of the authors’ knowledge, these equipment are not yet implemented. In this context, this paper presents an experimental stand for a fully automated liquid penetrant inspection line, which includes the development and use of dedicated imaging software used for real time interpretation of the images acquired using a digital camera. The novelty of the research consist in designing and building a fully-automated LPT stand, controlled by a soft which contains also a module for acquisition and image processing in real time without no human implication.
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Wari, Alan, Hendri Nurdin, and Kyaw Zay Ya. "Porosity Defect Analysis in ST 37 Steel Welding Joints Using the Dye Penetrant Method." Teknomekanik 3, no. 1 (May 25, 2020): 1–8. http://dx.doi.org/10.24036/tm.v3i1.5272.
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The procedures in the world of welding all look simple, but all welding that looks simple must have extensive knowledge in accordance with the definition of welding. This welding is a permanent connection technique, when the welding process takes place the results do not always meet the quality standards that have been determined. The cause of the welding results that do not meet the quality standards in the form of dirt on the material when before welding and so forth. The purpose of this study is that the specimen specimens are accepted according to the welding institute's standard acceptance criteria (TWI) This research uses st 37 steel by using SMAW welding electrodes LB 52U (E 7016) diameter 2.6mm for root, and LB 52U (E 7016) diameter 3.2 for fillers and caping with welding position 1G. Testing of welding results is carried out by the non destructive test of the dye penetrant method whose inspection results are determined based on the standard ASME. The results of this test study discontinuity in the form of porosity on the surface of the welding results in specimen 1, namely material contaminated by dirt, there are porosity defects scattered with a length of 6mm and porosity of 10mm so based on the standard TWI both test specimens were declared rejected, and in specimen 2, material that was not contaminated with impurities, there were porosity defects of 2mm and 2.5mm so that according to the standards of the two specimens the test was accepted. For the results of welding defects that are rejected can still be corrected by linking to the defects that, and can be done welding again.
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Ward, C. "The use of eddy current arrays as a replacement for dye-penetrant inspection of generator and exciter end-rings." Insight - Non-Destructive Testing and Condition Monitoring 47, no. 9 (September 1, 2005): 543–46. http://dx.doi.org/10.1784/insi.2005.47.9.543.
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DE BONI, Luis Alcides Brandini, and Jackson CAMANA. "REMOVAL OF DYE AND WATER RECYCLING FROM THE WASTEWATER OF THE LIQUID PENETRANT INSPECTION THROUGH THE ELECTROCOAGULATION AND THE FENTON REACTION." Periódico Tchê Química 12, no. 24 (August 20, 2014): 79–84. http://dx.doi.org/10.52571/ptq.v11.n22.2014.79_periodico_22_pgs_79_84.pdf.
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This paper describes the procedures used in the company Micromazza PMP to undertake the effluent treatment of the test by liquid penetrant inspection (LPI) used for the detection of cracks and micro cracks invisible to the naked eye in metallic products. It was used the Fenton reaction combined with electrocoagulation process to replace the impurities removal system with activated carbon. After the decontamination of the wastewater, the sludge was removed dehydrated and led to the landfill. The recovered water was odorless and colorless. The improvement in some quality standards analyzed as true color, COD and turbidity , was 99.36 % , 88.98 % and 99.34%, respectively. Due to the use of iron electrodes for the realization of the electrocoagulation process, a 15% increase in iron concentration in the effluent happened, howevert his does not exceeded the quality standards defined in CONAMA Resolution No. 430/2011.The results demonstrate that the process was efficient for the decontamination of wastewater arising from this quality control test (LPI).
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Thomas, Joby V., K. Thomas Tharian, C. R. Anoop, and P. Chakravarthy. "Influence of Filler Wire Material on Dissimilar Welding of 15-5PH to KC20WN (Haynes 25)." Materials Science Forum 830-831 (September 2015): 298–301. http://dx.doi.org/10.4028/www.scientific.net/msf.830-831.298.
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Many of the components/assemblies used in strategic sectors involve dissimilar metal weld joints and dissimilar welding has always imposed challenges in terms of the weld quality because of the physical and chemical mismatches of the base metals. In the present study, dissimilar welding of stainless steel 15-5PH (UNS S15500) to a Cobalt-base super alloy KC20WN (UNS R30605/ Haynes 25) is attempted for specific purpose in space applications. Gas Tungsten Arc Welding is carried out with two types of filler wires, viz., KC20WN and ER 630 (17-4PH). Visual inspection, Dye Penetrant testing and X-ray radiography testing revealed defect free joints and the joints were also characterized for microstructure. Superior properties were observed when welding was carried out with KC20WN filler wire compared to that with ER630 filler wire.
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Rajole, S., P. R. Sondar, S. Hiremath, and K. S. Ravishankar. "Failure Analysis of Industrial Discharge Hopper Pipe." Journal of Modern Manufacturing Systems and Technology 5, no. 1 (November 16, 2020): 1–6. http://dx.doi.org/10.15282/jmmst.v5i1.5149.
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This work presents the detailed investigation and root cause analysis of catastrophic failure of an industrial discharge hopper pipe. The hopper pipe investigated in the present work is made of austenitic stainless steel, 316 grade, a commonly used grade for valves, pipes and heat exchanger tubes. The pipe fractured in transverse direction, leading to the failure of discharge pipe. Visual inspection, dye penetrant test, chemical analysis, microstructural analysis, and fractography analysis were carried out on the failed part and it was concluded that stress corrosion cracking led to the failure of hopper pipe. The pipe constantly being under the exposure of industrial water and the presence of chlorine content in it made it susceptible for stress corrosion cracking. Transgranular fracture was clearly observed in the microstructure of failed sample and spot EDX at the fracture location confirmed the presence of chlorine content. Further, fractography showed striations indicating fatigue loading. The work concluded that stress corrosion cracking as the root cause of failure.
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Santella, Michael, X. Frank Chen, Philip Maziasz, Jason Rausch, and Jonathan Salkin. "Properties of a thick-section narrow-gap gas tungsten arc weld of cast Haynes 282." Welding in the World 65, no. 5 (January 28, 2021): 961–71. http://dx.doi.org/10.1007/s40194-021-01077-4.
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AbstractA 50.8-mm-deep gas tungsten arc weld was made with matching filler metal in cast Haynes 282 alloy. The narrow-gap joint was filled with 104 weld beads. Visual and dye-penetrant inspection of cross-weld specimens indicated that the cast base metal contained numerous casting defects. No visible indications of physical defects were found in the weld deposit. The weld heat-affected zone was characterized by microcracking and localized recrystallization. The cause of the cracking could not be determined. Hardness testing showed that a softened region in the as-welded heat-affected zone was nearly eliminated by post-weld heat treatment. Tensile testing up to 816 °C showed that cross-weld specimen strengths ranged from 57 to 79% of the cast base metal tensile strength. The stress-rupture strengths of cross-weld specimens are within 20% of base metal reference data. Failures of both tensile and stress-rupture specimens occurred in the base metal.
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Vukelic, Goran. "Assessment of a Boat Fractured Steering Wheel." Polish Maritime Research 23, no. 3 (September 1, 2016): 91–96. http://dx.doi.org/10.1515/pomr-2016-0037.
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Abstract During regular use of the steering wheel mounted on a boat, two cracks emanating from a fastener hole were noticed which, consequently, caused final fracture of the wheel. To determine the behavior of a boat steering wheel with cracks present, assessment of a fractured wheel was performed. Torque moments of the fasteners were measured prior to removing the steering wheel from the boat. Visual and dye penetrant inspection followed along with the material detection. Besides using experimental procedures, assessment of the fractured wheel was performed using finite element analysis, i.e. stress intensity factor values were numerically determined. Variation of stress intensity factor with crack length is presented. Possible causes of crack occurrence are given and they include excessive values of fastener torque moments coupled with fretting between fastener and fastener hole that was poorly machined. Results obtained by this assessment can be taken for predicting fracture behavior of a cracked steering wheel and as a reference in the design, mounting and exploitation process of steering wheels improving that way their safety in transportation environment.
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Negi, B. S. "Case Studies on Field Repairs of Stainless Steel Components in Refinery." Advanced Materials Research 794 (September 2013): 375–79. http://dx.doi.org/10.4028/www.scientific.net/amr.794.375.
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Stainless steels (SS) possess excellent corrosion, creep and high temperature oxidation resistance and are invariably used in refinery for construction of heater tubes, tube supports, Heat exchanger bundles, piping and internal lining of pressure vessels. Ferritic stainless steel type 405 is used for column strip-lining, martensitic stainless steel type 410 is used for column trays and heater tubes and austenitic stainless steel family is used very extensively for lining, piping, heat exchanger, heater tubes and tube supports. On-stream and turnaround condition monitoring of plant and equipment are carried out for health assessment and mitigation of premature failure. However, catastrophic failures of stainless steel due to stress corrosion cracking, thermal fatigue and stress relaxation cracking are encountered in addition to bulging and cracking of strip-lining. Field repairs of these components are required to be done. Stainless steels are difficult to weld due to low thermal conductivity, higher coefficient of thermal expansion, fissuring and solidification cracking problem during welding. Lower heat input and fast cooling facilitate the welding process. Welding of service exposed stainless steels is more challenging, as it has already undergone metallurgical degradation. Welding of stainless steels is carried out using TIG and SMAW process with matching electrode after establishing the welding specification procedures and welders qualification. Field repairs of stainless steels components are also attempted with original procedures and in case of difficulties, a buttering layer of inconel (ERNiCr3) or ER 309Mo is provided on the welding surface before using matching electrodes. Quality assurance of weld joint is ensured by stage-wise inspection and non-destructive testing. Dye penetrant test of root run and radiographic examination of final weld joint are most common. Post weld heat treatment is done as per code requirement. This Paper highlights three case studies on field repairs of stainless steel components in refinery. 1. Welding procedure followed for repair of bulged and cracked SS 316 strip-lining and cladding on carbon steel backing material. It is a dissimilar welding of SS 316L with degraded carbon steel. 2. Field welding of SS 347 Piping components, which has undergone thermal relaxation cracking at fillet joints. 3. Welding repair of SS 310 cast heater tube support conforming to A 297 Gr HK 40. The Paper also presents brief failure analysis with reasons and remedies.
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Hao, Xiao Jun, Ji Feng Zhao, Xiao Guang Niu, Xiang Feng Zheng, and Chang Fu Liu. "Research on NDT Technique for Thick-Walled Metal Parts of Power Stations." Advanced Materials Research 706-708 (June 2013): 1533–36. http://dx.doi.org/10.4028/www.scientific.net/amr.706-708.1533.
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A NDT technique suited to inspecting thick-walled metal parts of power stations is comprised of time-of-flight-diffraction technique, Pulse-echo technique and magnetic particle inspection technique or dye penetrate technique. Flaw sizing accuracy and probability of detection can be improved greatly with application of the technique, and the risk of components` failure can be decreased greatly.
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Sajuri, Z., A. R. Said, M. L. Ibrahim, and Junaidi Syarif. "Premature Failure of Gas Turbine Blade." Key Engineering Materials 462-463 (January 2011): 325–30. http://dx.doi.org/10.4028/www.scientific.net/kem.462-463.325.
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A set of first stage stationary blade of gas turbine was prematurely replaced due to severe cracking after 5,000 hours in operation. Failure investigation was conducted on damaged blades by non-destructive penetrant inspection, microstructure examination, chemical analysis, hardness mapping and fracture surface observation. The blade material, verified as IN738LC nickel superalloy, exhibited presence of elongated grain boundary carbides, TCP phases formation, and grain boundary creep void on the airfoil. Morphology of γ' precipitation, however, was normal throughout the blade with size of approximately 1μm and no significant coarsening. Presence of welding structure and possible brazing layer on the airfoil was detected suggesting that the blade was previously refurbished. Primary crack occurred on previous welding repair and propagated in transgranular mode. It was concluded that the blade failure was caused by improper welding repair despite evidence of base material degradation.
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Zong, Hua, He Zhang, and Jinghui Qiu. "Accurate Imaging of Wide Beam Active Millimeter Wave Based on Angular Spectrum Theory and Simulation Verification." Photonics 8, no. 9 (September 17, 2021): 397. http://dx.doi.org/10.3390/photonics8090397.
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Due to the fact that a millimeter-wave (MMW) has a strong ability to penetrate clothing, MMW holographic imaging technology can conduct a non-contact inspection of the human body’s surface. In recent years, personnel surveillance systems utilizing MMW holographic imaging technology has achieved rapid progress. However, limited by MMW holographic imaging’s image quality, the existing imaging technology cannot accurately detect whether the human body carries hidden objects. Additionally, real-time inspection requirements cannot be practically satisfied, and the system cost is relatively high. In this paper, a reconstruction algorithm with enhanced imaging quality, which can solve the problem of spherical wave attenuation with distance, making imaging results more accurate. The sampling conditions and imaging resolution are simulated and analyzed, which verify the azimuth resolution. Furthermore, the antenna beam’s holographic imaging simulation is optimized, effectively improving the quality of the reconstructed image. The proposed scheme provides theoretical support for determining antenna step and scanning aperture size in engineering and have theoretical guiding significance for improving the image quality of millimeter-wave holography and reducing system cost.
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Ismail, N. I., W. N. A. Rashid, and N. Lokmanulhakim. "Development of crack on composite detection sensor using magnetic induction concept." International Journal of Electrical and Computer Engineering (IJECE) 9, no. 6 (December 1, 2019): 5644. http://dx.doi.org/10.11591/ijece.v9i6.pp5644-5652.
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<p class="Text">A crack detection is very important to control the quality of the composite itself that been widely used in industries. There are quite a numbers of techniques which are used to detect the crack such as visual inspection, radiography, ultrasonic, eddy current magnetic particle, and penetrant testing. In this paper, it focuses on designing and implementing the system to detect a crack on the composite material using magnetic induction concept. At the early stage, the miniature of composite detection sensor using magnetic induction concept is designed using Comsol Multiphysics software to see the current induced from the system. The current value from the sensor is measured based on magnetic induction concept. A complete design of a system then is designed which include the sensor design, the main controller unit design and Bluetooth electronic application. The experiment results show that the magnetic induction concept can be used to detect crack by changing the value of current. When crack occurs the value of current will decrease due to the changes of magnetic induction.</p>
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Huang, Chi Kong, Chau Chen Torng, and Hsien Ming Chang. "Relationship between Saturation Curve and Peening Parameters for Aerospace Shot Peening Process." Materials Science Forum 561-565 (October 2007): 965–68. http://dx.doi.org/10.4028/www.scientific.net/msf.561-565.965.
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The shot peening process can improve the fatigue strength of machine parts of aero structures. Due to the strength requirement of aircraft, the shot peening is widely used in the manufacturing process. Most of shot peening parts peened after penetrate inspection to ensure no defect and crack on the surface, and then peen the shots on the surface of machine parts to increase the fatigue life. During the first article verification period, the saturation curve has to be created. The peening parameters of mass production would base on the peening parameters of saturation point of the saturation curve. By using statistical methodology to analysis saturation curve of shot peening process, this study tries to find the relationship between saturation curve and relative peening parameters, such as peening time, air pressure. The results of this analysis can provide an efficient and economical approach for the process engineer and technician to develop the new shot peening process.
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YANG, DONG-JO, CHOUL-JUN CHOI, and JAE-YEOL KIM. "EVALUATION METHOD OF GAS TURBINE BLADES COVERING INTEGRITY BY IR CAMERA." International Journal of Modern Physics B 20, no. 25n27 (October 30, 2006): 4329–34. http://dx.doi.org/10.1142/s0217979206041306.
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Key parts of the main equipment in a gas turbine may likely be damaged due to operation under high temperature, high pressure, high-speed rotation, etc. Accordingly, the cost for maintenance increases and the damaged parts may cause generation to stop. The surface of a blade is thermal-sprayed, using powder with main compositions such as Ni , Cr , Al , etc, in order to inhibit hot oxidation. Conventional regular maintenance of the coating layer of a blade is made by FPI (Fluorescent Penetrant Inspection) and MTP (Magnetic Particle Testing). Such methods, however, are complicated and take a long time and also require high cost. In this study, defect diagnostics were tested on the coating layer of an industrial gas turbine blade, using an infrared thermography camera. Since the infrared thermography method can check a temperature distribution by means of non-contact on a wide range of areas, it can advantageously save expense and time as compared to conventional test methods. For the infrared thermography method, however, thermo-load must be applied onto a tested specimen and it is difficult to quantify the measured data. To solve the problems, this paper includes description about producing a specimen of a gas turbine blade (bucket), applying thermo-load onto the produced specimen, photographing thermography images by an infrared thermography camera, analyzing the thermography images, and pre-testing to analyze defects on the coating layer of the gas turbine blade.
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Kwinta, G., S. Kara, B. Kalandyk, R. Zapała, and P. Pałka. "Microstructure Examinations in Corners of the Low-Carbon Steel Slabs from Continuos Caster Machine." Archives of Metallurgy and Materials 61, no. 4 (December 1, 2016): 2051–56. http://dx.doi.org/10.1515/amm-2016-0330.
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Abstract The exposed selvedge layers in slabs cast by the continuous process should be free from surface defects, which in most cases appear in the form of cracks on the casting surface and run to its interior. In addition to the parameters of the casting process, the occurrence of such defects depends on the chemical composition of cast steel, on the segregation of surface active elements and formation of the precipitates of carbides, nitrides and other phases. Due to the frequent occurrence of defects in corners of the slabs, non-destructive testing was performed on the mechanically cleaned surfaces of slabs. The test material was low-carbon API(American Petroleum Institute API 5L standard) steel micro alloyed with Nb and Ti designed for the production of pipes to handle gas, oil and other liquid and gaseous fuels. Despite the use of different methods of inspection, i.e. ultrasonic, magnetic particle and penetrant, cracks were not traced in the examined material. Then, from the corners of the examined slabs, specimens were cut out for metallographic examinations. The main purpose of these examinations was to disclose the presence of possible cracks and micro cracks on the surfaces transversal and longitudinal to the direction of casting. At the same time, studies were conducted to establish the number and morphology of non-metallic inclusions in selvedge layers of the slab corners and axis. Additionally, hardness of the slabs was measured. The conducted studies revealed only some minor differences in the slab hardness along its axis (130 ÷ 135 HB) and in selvedge layers (120 ÷ 123 HB).
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Armon, R., T. Arbel, and M. Green. "A quantitative and qualitative study of biofilm disinfection on glass, metal and PVC surfaces by chlorine, bromine and bromochloro-5,5 dimethylhydantoin (BCDMH)." Water Science and Technology 38, no. 12 (December 1, 1998): 175–79. http://dx.doi.org/10.2166/wst.1998.0535.
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The present study was conducted on artificial biofilm formed in a laboratory water system using three support surfaces: glass, galvanised iron and polyvinyl chloride (PVC). Biofilm formation was followed by direct count on R2A medium and by scanning electron microscope (SEM) examination. As described, the development of biofilm was not the same on the various surfaces. Biofilm formed on various surfaces had different disinfection patterns as shown by the experimental data. Chlorine was the most efficient disinfectant against biofilm developed on glass and metal surfaces but less effective on PVC. Disinfection of glass and PVC biofilms with bromine was much less effective. Bromochloro-5,5 dimethylhydantoin (BCDMH) was very effective on galvanised iron, less effective on PVC and almost no effect was observed on glass surfaces. Addition of EDTA (1mM) to the biofilm system, prior to disinfection, was more effective in killing the biofilm bacteria, probably due to chelation of divalent ions (Ca2+,Mg2+) which open the matrix and allow the disinfectant to penetrate easily. Maintaining the system at certain BCDMH concentrations, following a disinfection shock with bromine and chlorine, allowed the system to remain at a low level of bacteria. SEM inspection made it possible to follow the biofilm organisation on the various surfaces before and after disinfection. Following disinfection, on all surfaces, the biofilm bacteria seemed to be “flat” and, after addition of EDTA, detachment of the extracellular polysaccharide polymer (EPS) from the surface was observed. It seems that the EPS perforation process allowed better penetration of the disinfectant into the biofilm barrier affecting bacterial viability. The various chemical and microbiological aspects of biofilm disinfection and future practices are discussed.
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"An integrated dye penetrant inspection flow line." Aircraft Engineering and Aerospace Technology 76, no. 3 (June 2004). http://dx.doi.org/10.1108/aeat.2004.12776caf.004.
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Lana, A. R., and N. Idusuyi. "The Design, Construction and Testing of an Intelligent Device for Coating Flaws and Crack Detection in Pipelines." Journal of Engineering Research and Reports, August 6, 2019, 1–13. http://dx.doi.org/10.9734/jerr/2019/v6i316952.
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The major pollutant induced by pipeline failure in Oil and Gas industry has been mitigated over the years using non-destructive techniques like liquid penetrant, magnetic particles, radiographic, ultrasound and eddy current testing. The eddy current technique’s advantage over the other testing devices remains the best suitable in the design and construction of the devices due to the nature of the pipeline materials. For this present work, a pre-test-post-test experimental design was used to test devices on a defect free pipe and a pipe with machined defects of known dimensions and different orientation (longitudinal and axial) after construction. The defect detection was done using electromagnetic technique of eddy current by exciting a coil with power supply and placed close to the tested pipe surface, as a micro-controller was used to track the irregularities on the material surface by computer systems. The device set up for the test was a coil with a power supply of a DC battery connected with micro-controller of a quantization level of 4.88mV. For visual display, result obtained indicates no variation in the amplitude of the pulse as demonstrated by a pipe with no defect while variations (deeps) occurred in the pipe with defects as the coil was traversed over the defect. The orientation had no significant effects on the sensitivity and effectiveness of the device. Results validation was done using a non-destructive technique by visual inspection. Thus, device has shown its effectiveness in detecting defects irrespective of the orientation. Similarly, the size of the defects is a determinant in the amplitude variation of the pulse displayed which implies at higher sensitivity, a high frequency is required.
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Radhakrishnan, J. K., S. Nithila, S. N. Kartik, T. Bhuvana, G. U. Kulkarni, and U. K. Singh. "A Novel, Needle-Array Dry-Electrode With Stainless Steel Micro-Tips, for Electroencephalography Monitoring." Journal of Medical Devices 12, no. 4 (September 21, 2018). http://dx.doi.org/10.1115/1.4041227.
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A novel, needle array dry electrode consisting of 10 × 10 array of stainless steel (SS) Microtips was developed for electroencephalography (EEG) monitoring. The developed dry electrode uses commercially available, inexpensive, SS acupuncture needles certified for invasive use, to collect the EEG signal. The microtips of the acupuncture needles project out of a flat Teflon base by approximately 150 μm. Mechanical failure analysis was carried out, with theoretical calculations for individual needles and experimental measurements with a universal testing machine (UTM). The theoretically calculated critical load for failure for individual needle was 0.88 N, while the UTM measurements show the failure occurring at 0.95 N; this difference is probably due to the simplified assumptions used in calculations. The UTM measurements of the individual needle applied against a Silicone elastomer reveal that the force required for the penetration of the needle of the electrode into skin maybe as low as 0.01 N. Needle array insertion into silicone elastomer sheet and its optical inspection was carried out to assess the ability of the microneedles to penetrate the skin. The impedance of the electrode, measured in three electrode configuration in 0.9% NaCl solution, was approximately 6.8KΩ at 20 Hz, which is sufficiently low to fulfill the requirements of biopotential measurement. The construction and characteristics of the developed needle array dry electrode show that they are suitable for penetrating the stratum corneum of the skin and acquire the EEG signal directly from the interstitial fluidic layer underneath. The construction of the electrode and its mechanical and electrical characteristics show that it is a promising dry electrode for long duration EEG Monitoring.