Academic literature on the topic 'PDC bit wear'
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Journal articles on the topic "PDC bit wear"
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Wang, Zong Gang, Zhen Wei, and Lai Ju Han. "Microwave PDC Drill Bit." Advanced Materials Research 774-776 (September 2013): 1414–17. http://dx.doi.org/10.4028/www.scientific.net/amr.774-776.1414.
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On the rotary drilling system, the technologies for fracturing and cutting hard rock are mainly mechanical rock breaking methods by use of improving bottomhole water horse power and bit energy, and the working life and rock breaking efficiency have much room for improvement. Microwave crag broken is a thermal assisted rock breaking method which could melt rocks. Microwave assisted rock breaking method will not bring new impact, wear and tear, instead, the microwave pretreatment on the rock reduces the difficulty of breaking rock and prolongs the service life of the drill bit. Under the combined action of microwave heat and mechanical energy of PDC bit, the rock breaking efficiency is improved greatly, and the drilling cost is reduced significantly.
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Soegihardjo, Oegik, and Samuel Trinata. "Simulasi Perubahan Back Rake Angle Polycrystalline Diamond Carbide Drill Bit untuk Meminimalkan Keausan Pahat." Jurnal Teknik Mesin 17, no. 2 (October 8, 2020): 34–37. http://dx.doi.org/10.9744/jtm.17.2.34-37.
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The drilling process of an oil well uses a drill bit to drill a hole to drain crude oil from the bowels of the earth to the ground. Tool wear occurs in every cutting or drilling process that uses tool bits. A drill bit is the general term for the tool blade used in the drilling process. Two types of tool bits that are commonly used are roller cone and Polycrystalline Diamond Carbide drill bit or PDC. The case being study is the wear out of the PDC drill bit, that causing unplanned bit trip. This research was conducted as an effort to reduce the wear that occurs on the PDC drill bit. The aim of the research is to simulate the changes of the back rake angle, so that the impact of the back rake angle's changes on the wear of the drill bit could be investigated. The results of the simulations were compared with the tool wear data that occurred at one of the oil drilling locations.
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Jinping, Yu, Zou Deyong, Sun Yuanxiu, and Zhang Yin. "Simulation and Experimental Study of the Rock Breaking Mechanism of Personalized Polycrystalline Diamond Compact Bits." Journal of Engineering Science and Technology Review 13, no. 5 (2020): 122–31. http://dx.doi.org/10.25103/jestr.135.16.
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Rock breaking is a complex physical process that can be influenced by various factors, such as geometrical shape and cutting angle of rock breaking tools. Experimental study of the rock breaking mechanism of personalized bits is restricted due to long cycle and high cost. This study simulated the rock breaking mechanism of polycrystalline diamond compact (PDC) bit by combining finite element method and experiment. The simulation was performed to shorten the period and reduce the cost of studying the rock breaking mechanism of PDC bits. A rock breaking finite element model for sting cutters of personalized PDC bit was established to simulate the rock breaking process. The crack propagation pattern, dynamic stress of rock breaking, and rock breaking mechanism of sting cutters of personalized PDC bit were analyzed. The correctness of the simulation results was verified through experiments. Results demonstrate that the rock breaking load increases with the crack propagation in the fracture initiation and propagation stages, with the maximum tangential force of 1062.5 N and maximum axial force of 1850.0 N. The load changes in a small range when the crack penetrates the rock, with the tangential force of 125.0–500.0 N and axial force of 375.0–875.0 N. The rock breaking mechanism of the sting cutters of bit is consistent with maximum tensile stress theory. The rock begins to break when the tensile stress of rock is 36.9 MPa. The sting cutters of personalized PDC bit have better wear resistance than the sting cutters of conventional bit. The average wear rates of personalized PDC and conventional bits are 1.74E-4 and 2.1E-4 mm/m, respectively. This study serves as reference for shortening the study period of rock breaking mechanism, efficiently designing personalized PDC bit structure, reducing bit wear, and enhancing rock breaking efficiency.
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Ayop, Ahmad Zhafran, Ahmad Zafri Bahruddin, Belladonna Maulianda, Aruvin Prakasan, Shamammet Dovletov, Eziz Atdayev, Ahmad Majdi Abdul Rani, et al. "Numerical modeling on drilling fluid and cutter design effect on drilling bit cutter thermal wear and breakdown." Journal of Petroleum Exploration and Production Technology 10, no. 3 (October 11, 2019): 959–68. http://dx.doi.org/10.1007/s13202-019-00790-7.
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Abstract The unconventional reservoir geological complexity will reduce the drilling bit performance. The drill bit poor performance was the reduction in rate of penetration (ROP) due to bit balling and worn cutter and downhole vibrations that led to polycrystalline diamond compact (PDC) cutter to break prematurely. These poor performances were caused by drilling the transitional formations (interbedded formations) that could create huge imbalance of forces, causing downhole vibration which led to PDC cutter breakage and thermal wear. These consequently caused worn cutter which lowered the ROP. This low performance required necessary improvements in drill bit cutter design. This research investigates thermal–mechanical wear of three specific PDC cutters: standard chamfered, ax, and stinger on the application of heat flux and cooling effect by different drilling fluids by using FEM. Based on simulation results, the best combination to be used was chamfered cutter geometry with OBM or stinger cutter geometry with SBM. Modeling studies require experimental validation of the results.
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Kong, Chunyan, Rongjun Zhu, Derong Zhang, and Shuangshuang Li. "Research on kinematics analysis of spherical single-cone PDC compound bit and rock breaking simulation verification." Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles 76 (2021): 52. http://dx.doi.org/10.2516/ogst/2021034.
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The single-cone bit has become the first choice for slim hole sidetracking and deep well drilling with its unique rock breaking method and high ROP (Rate Of Penetration), with its main failure mode being of early excessive wear of the cutting teeth. In order to improve the adaptability of single-cone bits to hard and highly abrasive formations, a spherical single-cone Polycrystalline Diamond Compact (PDC) compound bit is designed. According to the characteristics of the tooth profile, the way of tooth arrangement and the way of contact between the cutting teeth and the rock, the acceleration equation to the cutting teeth of the spherical single-cone PDC compound bit is established. The acceleration of the single-cone bit is verified by numerical simulation experiment of rock-breaking. The shaft inclination angle of the cone, the position and height of the PDC teeth, the radius of the PDC teeth, the lateral rotation angle and the front inclination angle on the acceleration are studied. The results show that as the shaft inclination angle increases, the bit transmission ratio gradually increases, and the harder the rock formation, the larger the transmission ratio of the single-cone bit; the shaft inclination angle and the position of the PDC tooth have a greater influence on the acceleration of the PDC tooth, and the radius, lateral rotation angle and front inclination angle of the PDC tooth have a small influence on the acceleration of the PDC tooth; rock properties have an impact on the acceleration of the cutting teeth, with the acceleration of the cutting teeth in hard rock formations being higher than that in soft rock formations; near the top of the cone, the absolute acceleration of the cutting teeth will fluctuate sharply and cause severe wear of the cutting teeth, so the tooth distribution in this area should be strengthened; on the premise that the bearing life of the single-cone bit is allowed, the value of the shaft inclination angle β can be approached to 70°. The relative error between the theoretical analysis results of the acceleration of the PDC cutter and the rock-breaking simulation experiment results is between −0.95% and −2.24%. This research lays a theoretical foundation for the dynamic research of spherical single-cone PDC compound bit.
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Hough, C. L., B. Das, and T. G. Rozgonyi. "Life Models for Small-Diameter Polycrystalline Diamond Compact Bits in Hard Abrasive Media." Journal of Energy Resources Technology 108, no. 4 (December 1, 1986): 310–14. http://dx.doi.org/10.1115/1.3231282.
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Mathematical models for bit life of polycrystalline diamond compact (PDC) drill bits were developed for drilling small holes in hard abrasive media. Based on the wear-out criterion of an average 0.060 in. (1.5 mm) flank wear land, bit life equations were formulated in three forms: bit life versus rotary speed and feed rate, bit life versus rotary speed and penetration rate, and wear rate versus cutting speed and cutter engagement area. The traditional linear-logarithmic model proved inadequate to describe bit life, whereas the quadratic-logarithmic model provided the best bit life prediction equation. Consequently, it would be possible to predict the optimum economical drilling conditions more accurately by employing a quadratic-logarithmic based bit life equation. The equation demonstrated the ability to predict the bit life precisely under different modes of wear.
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Abdul-Rani, A. M., M. Zamri Ismail, M. Ariff Zaky, M. Hariz M. Noor, Y. Y. Zhun, K. Ganesan, T. V. V. L. N. Rao, Subhash Kamal, and Turnad Lenggo Ginta. "Improving Rate of Penetration for PDC Drill Bit Using Reverse Engineering." Applied Mechanics and Materials 607 (July 2014): 153–60. http://dx.doi.org/10.4028/www.scientific.net/amm.607.153.
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In petroleum industry, drilling is one of the most important aspects due to its economics. Reduction in drilling time is desired to minimize operations cost. This work focus on Polycrystalline Diamond Compact (PDC) drill bit which is categorized as a fixed cutter drilling bit. Problem such as wear and tear of PDC cutter are some of the main factors in drilling process failure affecting the rate of penetration (RoP). Thus, an intensive study in drill bit design could potentially save costs if the drill bit efficiency can be improved. The objective of this research is to improve the PDC cutter design and analyse design improvement in relation to the rate of penetration using reverse engineering (RE) approach. RE method is capable of resolving unavailable drill bit blueprint from the manufacturer due to propriety and confidential. RE non-contact data acquisition device, 3D laser scanner will be used to obtain cloud data of the existing worn drill bit. Computer Aided Design (CAD) software is used to convert cloud data of the PDC drill bit into 3D CAD model. Optimization of PDC Drill bit is focused on feature design such as back rake angle, side rake angle and number of cutters. CAE software is used to analyse the effect of the design feature modification to rate of penetration. Results show rate of penetration increases as the angle of both rake angle and number of cutter decreases.
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Tretyak, A. A., K. A. Borisov, and A. N. Grossu. "Method of Calculating the Wear, ROP and PDC Bit Operating Time." IOP Conference Series: Earth and Environmental Science 272 (June 21, 2019): 022214. http://dx.doi.org/10.1088/1755-1315/272/2/022214.
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Glowka, D. A., and C. M. Stone. "Thermal Response of Polycrystalline Diamond Compact Cutters Under Simulated Downhole Conditions." Society of Petroleum Engineers Journal 25, no. 02 (April 1, 1985): 143–56. http://dx.doi.org/10.2118/11947-pa.
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Abstract An analytical method is developed to predict temperatures in polycrystalline diamond compact (PDC) drag cutters under steady-state and transient downhole conditions. The method is used to determine mean wearflat temperatures for cutters under conditions used in previous experiments to measure cutter wear. A correlation between wearflat temperatures and cutter wear rates is demonstrated, and it is shown that, for the particular rock type tested, cutter wear rates increase significantly above 350 degrees C [662 degrees F]. The concept of a critical weight on bit, above which wearflat temperatures exceed this value, is introduced. The effects of several parameters on the critical WOB are examined. These include cutter thermal conductivity, diamond layer thickness, rock properties. convective cooling, bit balling, and transient events such as bit bounce. Preliminary results of thermal stress modeling show that Preliminary results of thermal stress modeling show that plastic yielding of the cutter structure can occur under plastic yielding of the cutter structure can occur under certain downhole conditions. Introduction Drill bits using PDC drag cutters have been used for the past few years with considerable success in the oil and past few years with considerable success in the oil and gas drilling industry. Such bits have been shown to be quite sensitive, however, to formation characteristics and operating conditions, and the economic success of a particular bit run is highly dependent on identifying particular bit run is highly dependent on identifying appropriate drilling intervals and operating the bit within its limits. Our interest in PDC bit technology has been in determining the drilling potential of these bits in the more severe environments associated with geothermal resources. This paper addresses the thermal limitations of PDC bits in such environments and investigates the effects of design and operating parameters on these limitations. The work reported in this paper is an extension of work reported earlier. More generalized boundary conditions are used for the finite element thermal modeling of single PDC cutters. The results are used to demonstrate the PDC cutters. The results are used to demonstrate the apparent adverse effect of operating temperature on cutter wear rates. A more restrictive safe operating limit of 350 degrees C [662 degrees F] is proposed, rather than the 750 degrees C [1,382 degrees F] limit assumed in the earlier work. Cutter Temperature Theory and Analysis The thermal phenomena considered in this analysis are frictional heating and convective cooling of PDC cutters under downhole drilling conditions. Fig. 1 is a graphical representation of this process. Because of the relative motion between the cutter and the rock, frictional heat is generated at the interface. The total quantity of frictional heat per unit wearflat area per unit time is (1) Because of the intimate contact between the cutter and the rock, this heat flux is divided between the cutter, Q1, and the rock, Qf, according to the value of the energy partitioning fraction a: partitioning fraction a: (2) and (3) The value of a depends on the relative thermal resistances of the cutter and the rock, which in turn depend on their thermal properties, convective cooling rates, cutting speed, and cutter geometry. A measure of the thermal resistance of the rock is obtained from the literature. Jaeger gives the solution for the mean temperature rise of the contact area between a sliding, square heat source and the surface of a semi-infinite slab as (4) where khf and af are thermal properties of the rock, L is the wearflat length parallel to the cutting direction, and v is the coning speed. Because of the intimate contact between the cutter and the rock, it may be assumed that (5) Combining Eqs. 2 through 5 and assuming that the wellbore has been cooled by the drilling fluid such that Tf = Tfl, the general result is (6) SPEJ p. 143
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Poletto, Flavio. "Energy balance of a drill-bit seismic source, part 2: Drill-bit versus conventional seismic sources." GEOPHYSICS 70, no. 2 (March 2005): T29—T44. http://dx.doi.org/10.1190/1.1897039.
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The radiation properties of a downhole drill-bit seismic source are related to the amplitude and frequency of the forces exerted by the working bit. The main vibration modes of roller-cone and polycrystalline diamond compact (PDC) bits are investigated under different drilling conditions. The analysis includes vibrations produced by teeth indention, multilobed patterns, bouncing with periodic and random effects, single-cutter forces, stick-slip and whirling effects, mud-pressure modulation forces, and bit wear. Drill-bit radiation properties are calculated using the results obtained in part 1 of this paper and are numerically compared to the radiation of conventional vertical seismic profiling (VSP) sources.
Dissertations / Theses on the topic "PDC bit wear"
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Mazen, Ahmed Z., Nejat Rahmanian, Iqbal M. Mujtaba, and A. Hassanpour. "Effective mechanical specific energy: A new approach for evaluating PDC bit performance and cutters wear." Elsevier, 2020. http://hdl.handle.net/10454/18154.
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YesPredicting the PDC bit performance during drilling operation is important for the cost effectiveness of the operation. The majority of PDC bits are assessed based on their performance that are relative to offset wells. Determination of mechanical specific energy (MSE) in real time and compare it with the known MSE for a sharp bit to assess the bit life has been utilized by several operators in the past. However, MSE still cannot be used to predict the bit performance in exploration wells and also it cannot assess the bit efficiency in the inner and outer cones. A more precise approach needs to be devised and applied to improve the prediction of bit life and the decision when to pull the bit out of the hole. Effective mechanical specific energy (EMSE) developed in this work is a new wear and performance predictive model that is to measure the cutting efficiency based on number of cutters, which contact the rock as a function of weight on bit (WOB), rotary speed (RPM), torque, and depth of cut (DOC). This model modifies the previous MSE model by incorporating such parameters and including detailed design of the bit, number of blades, cutter density, cutter size, and cutting angle. Using this approach together with the analysis of rock hardness, a level of understanding of how the drilling variables influence the bit performance in the inner and outer cone is improved, and a convenient comparison of the bit condition in the frame of the standard bit record is achieved. This work presents a new simple model to predict the PDC cutters wear using actual data from three sections drilled in three oil wells in Libya. It is found that the obtained results are in well agreement with the actual dull grading shown in the bit record.
The full-text of this article will be released for public view at the end of the publisher embargo on 20 Oct 2021.
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Yahiaoui, Malik. "Comportement tribologique de diamants polycristallins et de carbures cémentés WC-Co avec traitements de graduation : application aux inserts et taillants d'outils pour le forage de formations rocheuses fortement abrasives." Thesis, Toulouse, INPT, 2013. http://www.theses.fr/2013INPT0052/document.
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La performance des inserts d’outils tricône et des taillants d’outils PDC commerciaux est soumise au compromis dureté/ténacité principalement régi par la proportion de cobalt et la taille des grains de carbures cémentés WC-Co et du PDC. Les traitements de graduation basés sur l’imbibition de cobalt et les revêtements de nitrure de bore des carbures cémentés permettent d’augmenter la résistance à l’abrasion au niveau de la surface active des inserts et des taillants tout en générant une ténacité accrue au cœur des carbures cémentés. Des essais d’usure à l’aide d’un tribomètre rotatif avec une contreface en alumine pour les inserts WC-Co et à l’aide d’un tour d’usure avec une contreface en béton à forte teneur en silice pour les taillants ont permis d’étudier leur comportement tribologique. Pour les inserts, le coefficient de frottement et les cinétiques d’usure (modèle d’Archard), mais aussi l’évaluation de la température de contact et de l’émission acoustique générée au contact, ont permis de mieux comprendre l’effet des traitements réalisés sur les carbures cémentés. Pour les taillants PDC un modèle de qualité, basé sur un compromis usure/efficacité de coupe, a été développé afin de caractériser la résistance à l’usure des taillants. Des analyses physicochimiques (EDX, DRX, Raman) ont permis d’associer l’évaluation de la résistance à l’abrasion des échantillons à des mécanismes d’usure en considérant les éléments constitutifs des systèmes tribologiques et la formation de troisièmes corps. Les résultats ont ainsi montré l’importance de la proportion de cobalt générée dans les débits d’usure sur la stabilité des débris abrasifs (alumine et silice) et ainsi sur la résistance à l’usure des inserts et taillants. Les mécanismes de rupture des microstructures WC-Co et PDC sont aussi mis en avant afin d’expliquer leur influence sur la résistance à l’abrasion des échantillons. Enfin, des mesures de ténacité des inserts ont permis de juger de l’apport des traitements d’imbibition sur la résistance à la propagation de fissures des carbures cémentés WC-Co. Aussi, des essais complémentaires de chocs ont permis de montrer que les traitements améliorant la résistance à l’abrasion des taillants ne se traduisent pas par la chute de leur résistance aux chocsThe performance of commercial tricone bit inserts and PDC bit cutters is defined by the compromise between hardness and fracture toughness controlled by the cobalt proportion and the grain size of WC-Co cemented carbide and PDC. On one hand, graduation treatments based on reactive imbibition of cobalt and boron nitride coating of cemented carbides lead to an improvement of abrasive wear resistance of inserts and cutters active surfaces. On the other hand, greater fracture toughness is obtained in the cemented carbides core as a result of imbibition. Wear experiments were performed with a rotary tribometer using an alumina contreface for the WC-Co inserts and with a lathe and its silica based concrete contreface for the PDC cutters. For the inserts, the friction coefficient and wear kinetics (Archard model), but also contact temperature measurement and acoustic emission consideration, permitted to clarify the treatments effects on cemented carbides tribological behaviour. For PDC cutters, a quality model, based on wear/cutting efficiency compromise, was developed in order to characterize the wear resistance. Physicochemical analyses (EDX, XRD, Raman) made a link between mechanical results and wear mechanisms considering the tribological systems and the third body formation. These analyses highlighted the influence of the proportion of cobalt generated in the wear flows on the stability of abrasive debris (alumina and silica) and thus on the wear resistance of inserts and cutters. The Fracture mechanisms of WC-Co and PDC microstructures have also been studied and their effects on the wear resistance have been demonstrated here. At last, fracture toughness measurements showed that the imbibition treatments could maintain a good resistance to cracks propagation of inserts. In addition, complementary impacts experiments prove that the improvement of wear resistance of PDC cutters did not produce reduction of impact strength
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Tuchman, Paula Schrier. "Weak but not meek an international society explanation of asymmetric deterrence /." access full-text, 1995. http://libweb.cityu.edu.hk/cgi-bin/ezdb/umi-r.pl?9601994.pdf.
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Mazen, Ahmed Z., Iqbal M. Mujtaba, A. Hassanpour, and Nejat Rahmanian. "Mathematical modelling of performance and wear prediction of PDC drill bits: impact of bit profile, bit hydraulic, and rock strength." 2019. http://hdl.handle.net/10454/17832.
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YesThe estimation of Polycrystalline Diamond Compact (PDC) cutters wear has been an area of concern for the drilling industry for years now. The cutter's wear has been measured practically by pulling the bit out for evaluation at the surface. It is important to find the right time for tripping out as this helps to avoid the fishing job and reduces the operational cost significantly. The prediction of the drilling performance is based on the interaction of cutter and rock. Several authors focused on the cutter-rock interface but only a few researchers tried to model the wear of the PDC bit cutters. The aim of this research is to understand the relationships between the rate of penetration (ROP) and the drilling variables per each foot, and then determine the overall bit efficiency for the whole drilling operation. A new mathematical model is derived to predict the PDC bit performance by considering the factors that were already not taken into account. These factors include rock strength, bit design, and bit hydraulic. The model investigates the effect of these parameters to estimate the abrasive cutters wear on the inner and the outer bit cones by deriving modified equations to calculate the mechanical specific energy (MSE), torque, and depth of cut (DOC) as a function of effective blades (EB). The model is used to forecast the bit cutters wear conditions in four wells in the oil fields located in Libya, which were drilled with three different PDC's sizes. The model enables the results to be compared to the actual bit cutters wear measured for inner and outer cones. The results are found that are well in agreement with the actual field data obtained in bit records.
Financial support from ministry of higher education in Libya.
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Mazen, Ahmed Z., Nejat Rahmanian, Iqbal M. Mujtaba, and A. Hassanpour. "Prediction of Penetration Rate for PDC Bits Using Indices of Rock Drillability, Cuttings Removal, and Bit Wear." 2020. http://hdl.handle.net/10454/18242.
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noPredicting rate of penetration (ROP) has gained considerable interest in the drilling industry because it is the most-effective way to improve the efficiency of drilling and reduce the operating costs. One way to enhance the drilling performance is to optimize the drilling parameters using real-time data. The optimization of the drilling parameters stands on the fact that drilling parameters are interrelated; that is, corrections in one factor affect all the others, positively or negatively. Analysis of the available models in the literature showed that they did not take into account all factors, and therefore, they might underestimate the ROP. To improve the accuracy of predicting the bit efficiency, a new ROP model is developed to preplan and lower the drilling costs. This approach introduces three parts of the process that were developed to describe the challenge of predicting ROP: aggressiveness or drillability, hole cleaning, and cutters wear, which are interrelated to each other. The approach discusses each process individually, and then the influence of all three factors on ROP is assessed. Taking into account the drilling parameters and formation properties, ROP1 is estimated by use a new equation. Then, lifting the produced cutting to the surface and evaluating how that affects the bit performance is proposed in the second part of the process (hole cleaning). Finally, wear index is introduced in the third part (wear condition) to predict the reduction of ROP2 caused by cutter/rock friction. The approach serves and could be considered as a baseline to identify all factors that can affect the bit performance. The developed model equations are applied to estimate ROP in three vertical oil wells with different bit sizes and lithology descriptions in Libya. The results indicate that the driven model provides an effective tool to predict the bit performance. The results are found in good agreement with the actual ROP values and achieve an enhancement of approximately 40% as compared to the previous models.
Books on the topic "PDC bit wear"
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Isett, Philip. Introduction. Princeton University Press, 2017. http://dx.doi.org/10.23943/princeton/9780691174822.003.101.003.0001.
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In the paper [DLS13], De Lellis and Székelyhidi introduce a method for constructing periodic weak solutions to the incompressible Euler equations{∂tv+div v⊗v+∇p=0 div v=0in three spatial dimensions that are continuous but do not conserve energy. The motivation for constructing such solutions comes from a conjecture of Lars Onsager [Ons49] on the theory of turbulence in an ideal fluid. In the modern language of PDE, Onsager's conjecture can be translated as follows....
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Effer-Uhe, Daniel, and Alica Mohnert, eds. Vertragsrecht in der Coronakrise. Nomos Verlagsgesellschaft mbH & Co. KG, 2020. http://dx.doi.org/10.5771/9783748909279.
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Der Ausbruch der Coronakrise verunsichert, aber Verträge sind in der Welt. Was hat Bestand, was bedarf der Anpassung? <b>Der Tagungsband</b> dokumentiert die Beiträge der Online-Tagung „Vertragsrecht in der Coronakrise“ in zitationsfähiger Form. Von grundlegenden dogmatischen Aspekten wie dem allgemeinen Leistungsstörungsrecht über das massenhaft relevante Verbraucher- sowie Mietrecht bis hin zu Spezialfragen in der Insolvenz beantworten Rechtsexperten die drängenden Fragen in der Pandemie, z.B. Wer trägt die Hotelkosten, wenn ein Pauschalreisender wegen Flugausfällen an der Rückreise gehindert ist? Können Arbeitnehmer auf erhöhte Schutzvorkehrungen im Betrieb pochen? Wer haftet, wenn eine Warenlieferung an der Landesgrenze durch überlange Kontrollen verspätet eintrifft oder zwischenzeitlich verdirbt? <b>Herausgeber und Autoren</b> Herausgegeben von PD Dr. Daniel Effer-Uhe und Dipl.-Psych. Alica Mohnert, Mag. iur., LL.M. (CUPL). Mit Beiträgen von Dr. Caspar Behme, Ludwig-Maximilians-Universität München; Dr. Jonas Brinkmann, Universität Bielefeld; Dr. Ann-Marie Kaulbach, Universität zu Köln; Stephan Klawitter, Humboldt-Universität zu Berlin; Jun.-Prof. Dr. Andreas Maurer, Universität Mannheim; PD Dr. Patrick Meier, Notarassessor, Julius-Maximilians-Universität Würzburg; Jun.-Prof. Dr. Jens Prütting, Rechtsanwalt, Bucerius Law School Hamburg; Prof. Dr. Thomas Riehm, Universität Passau; Prof. Dr. Jens M. Schmittmann, Rechtsanwalt, Mitglied des Senats für Anwaltssachen des Bundesgerichtshofs, FOM Hochschule Essen; Dipl.-Kfm. Dr. Bernd Scholl, Rechtsanwalt, Universität zu Köln.
Book chapters on the topic "PDC bit wear"
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Borisov, K. A., and A. A. Tretyak. "Method of calculating the wear and PDC bit operating time." In Topical Issues of Rational Use of Natural Resources 2019, 791–95. CRC Press, 2019. http://dx.doi.org/10.1201/9781003014638-40.
Full textConference papers on the topic "PDC bit wear"
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Witt-Doerring, Ysabel, Paul Pastusek Pastusek, Pradeepkumar Ashok, and Eric van Oort. "Quantifying PDC Bit Wear in Real-Time and Establishing an Effective Bit Pull Criterion Using Surface Sensors." In SPE Annual Technical Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/205844-ms.
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Abstract It is useful during drilling operations to know when bit failure has occurred because this knowledge can be used to improve drilling performance and provides guidance on when to pull out of hole. This paper presents a simple polycrystalline diamond compact (PDC) bit wear indicator and an associated methodology to help quantify wear and failure using real-time surface sensor data and PDC dull images. The wear indicator is used to identify the point of failure, after which corresponding surface data and dull images can be used to infer the cause of failure. It links rotary speed (RPM) with rate of penetration (ROP) and weight-on-bit (WOB). The term incorporating RPM and ROP represents a "sliding distance", i.e. the number of revolutions required to drill a unit distance of formation, while the WOB represents the formation hardness or contact pressure applied by the formation. This PDC bit wear metric was applied and validated on a data set comprised of 51 lateral production hole bit runs on 9 wells. Surface electric drilling recorder (EDR) data alongside bit dull photos were used to interpret the relationship between the wear metric and observed PDC wear. All runs were in the same extremely hard (estimated 35 – 50 kpsi unconfined compressive strength) and abrasive shale formation. Sliding drilling time and off-bottom time were filtered from the data, and the median wear metric value for each stand was calculated versus measured hole depth while in rotary mode. The initial point in time when the bit fails was found to be most often a singular event, after which ROP never recovered. Once damaged, subsequent catastrophic bit failure generally occurred within drilling 1-2 stands. The rapid bit failure observed was attributed to the increased thermal loads seen at the wear flat of the PDC cutter, which accelerate diamond degradation. The wear metric more accurately identifies the point in time (stand being drilled) of failure than the ROP value by itself. Review of post-run PDC photos show that the final recorded wear metric value can be related to the observed severity of the PDC damage. This information was used to determine a pull criterion to reduce pulling bits that are damaged beyond repair (DBR) and reduce time spent beyond the effective end of life. Pulling bits before DBR status is reached and replacing them increases overall drilling performance. The presented wear metric is simple and cost-effective to implement, which is important to lower-cost land wells, and requires only real-time surface sensor data. It enables a targeted approach to analyzing PDC bit wear, optimizing drilling performance and establishing effective bit pull criteria.
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Cheatham, C. A., and D. A. Loeb. "Effects of Field Wear on PDC Bit Performance." In SPE/IADC Drilling Conference. Society of Petroleum Engineers, 1985. http://dx.doi.org/10.2118/13464-ms.
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Maouche, Z., F. Al-Rawahi, I. Agapie, M. Parasher, and Talal Al Nahwi. "New PDC Bit Technology Sets the Standards in Drilling Hard and Abrasive Formations in Oman - Case Study." In IADC/SPE Asia Pacific Drilling Technology Conference. SPE, 2014. http://dx.doi.org/10.2118/spe-170462-ms.
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Abstract Historically, the hardest and most abrasive rock formations in Oman have been drilled using either diamond-protected, roller-cone insert bits or impregnated bits in combination with high-speed drives. Polycrystalline diamond compact (PDC) bits have been successfuly used to drill soft and non-abrasive formations to depths of approximately 2, 500 m. Within this region, all previous attempts to drill deeper into the hard and abrasive intervals have resulted in rapid bit wear, poor rate of penetration (ROP), and repetitive trips for bit change. A new PDC cutter technology combined with a novel multi-level cutting structure force balancing has extended the PDC bit footprint, setting new records for drilling the longest intervals of hard and abrasive sandstone formation in Oman. This new technology is the result of a program committed to two years of research, which focused on the improvement of PDC cutter wear and impact resistance, as well as addressing bit vibration and wear distribution issues. As a result, Halliburton DBS PDC bits have become the standard for drilling hard and abrasive rock in the Middle East, providing significant improvement with respect to distances drilled and ROP. In rotary mode, or in combination with low-cost drives, this new technology has drastically reduced the operational cost per foot drilled in Oman.
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Gouda, Gamal Mohamed, Michele Maestrami, Mohamed Ahmed Abu Saif, Shohdy Shalaby El-Moghrebi, Abdel Sattar Abdel Hamid Dahab, and Mohamed Shehate Farehat. "A Mathematical Model To Compute The Pdc Cutter Wear Value To Terminate PDC Bit Run." In SPE Middle East Oil and Gas Show and Conference. Society of Petroleum Engineers, 2011. http://dx.doi.org/10.2118/140151-ms.
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Glowka, D. A. "Implications of Thermal Wear Phenomena for PDC Bit Design and Operation." In SPE Annual Technical Conference and Exhibition. Society of Petroleum Engineers, 1985. http://dx.doi.org/10.2118/14222-ms.
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Liu, Z., C. Marland, D. Li, and R. Samuel. "An Analytical Model Coupled With Data Analytics to Estimate PDC Bit Wear." In SPE Latin America and Caribbean Petroleum Engineering Conference. Society of Petroleum Engineers, 2014. http://dx.doi.org/10.2118/169451-ms.
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Zhao, Dapeng, and Sigbjørn Sangesland. "Dynamical Analysis of Drill Bit With Ultrasonic Vibration." In ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/omae2015-41058.
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Based on the bit-rock interaction laws, a simple nonlinear 2-dofs mass-spring model is developed to analyze the dynamic cutting process with normal ultrasonic vibration excitation. The study presents a single cutter used in Polycrystalline-Diamond-Compact (PDC) drill bits. Using the 4th Runge-Kutta’s algorithm, numerical simulation found that ultrasonic vibration-induced contact deflection and even loss of contact. The contact friction between the rock and wear-flat (wear surface), which relates to the reaction force, is therefore reduced. This will reduce the wear on the cutter and the force needed to cut the rock. This indicates that the average reduction of friction induced by ultrasonic vibration can be explained by decreasing the average normal force on the cutter-rock wear-flat, rather than changing the friction coefficient.
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Tikhonov, Vadim, Olga Bukashkina, and Raju Gandikota. "Stick-Slip Model for PDC Bits Accounting for Coupled Torsional and Axial Oscillations." In ASME 2014 12th Biennial Conference on Engineering Systems Design and Analysis. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/esda2014-20026.
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Drilling with PDC bits can cause severe torsional and axial oscillations. These oscillations are accompanied by periodic sticking of the bit followed by accelerated rotation. The so-called “stick-slip” increases bit wear and fatigue and causes premature failure of BHA and drillstring components. It is well known that these torsional oscillations are nonlinear and self-induced. The present study investigates the coupling between axial and torsional oscillations. The cutting process is based on the Detournay model, which provides for the effect of the bottomhole pressure and the local pore pressure. The axial stiffness of the drillstring is taken into account with the axial motion equations coupled with the torsional equations, in contrast to previous models where axial equations were considered independently. Axial oscillations are allowed to occur even when the bit is in the stick phase. The new model also includes bit “bouncing” when it loses contact with the bottomhole. The equations are solved by time integration. By results of the analysis of transient processes the spectral density is determined. The objective of the paper is to improve understanding of stick-slip oscillation nature and assess the contribution of parameters that influence their intensity. The study includes the effect of the rotor rpm, intrinsic specific energy of rock, number of PDC blades, wear flat length of blades, etc. Results of the study will help drillers to select and change drilling parameters more efficiently to reduce severe stick-slip oscillations.
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Geoffroy, H., D. Nguyen Minh, J. Bergues, and C. Putot. "Frictional Contact On Cutters Wear Flat and Evaluation of Drilling Parameters of a PDC Bit." In SPE/ISRM Rock Mechanics in Petroleum Engineering. Society of Petroleum Engineers, 1998. http://dx.doi.org/10.2118/47323-ms.
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Trivedi, Ajesh Sanjay, Masood Mostofi, and Roman J. Shor. "Experimental Investigation of Induced Low Frequency Axial Vibration on Drilling Response of a PDC Bit." In SPE/IADC International Drilling Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/204024-ms.
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Abstract This study investigates the impact of induced low frequency axial excitations on drilling actions of Polycrystalline Diamond Compact (PDC) bits. Variations in drilling efficiency have been documented through a series of experiments at different intensities (frequency and amplitude) of axial excitations. Prior work has identified the challenges of bit wear due to high frequency oscillations and an experimental validation is conducted to incorporate vibration related force changes into mechanical specific energy (MSE) to allow for identification while drilling. Axial vibrations were induced using a controlled linear actuator at the cutter-rock interface, in low frequency regime (up to 5 Hz) using a rotary experimental setup, based on state-of-the-art modified lathe machine. Through imposition of bit kinematics of angular velocity and rate of penetration (ROP), a PDC cutter was used to drill several cores of donnybrook sandstone, at a constant angular velocity of 100 revolutions per minute (RPM). A piezoelectric triaxial sensor measured the cutting forces: normal (weight) and shear (torque) force, at the cutter-rock interface. The results quantify variation of drilling response under several combinations of frequency, amplitude and cutting speed. It was observed that forces required to penetrate through rock were reduced with minimum effect on degree of wear on the cutter, mainly due to lower intensity of induced oscillations. This shows that once periodic axial oscillations are imposed, a lesser amount of energy is required to achieve same rate of penetration (ROP), thereby indicating improvement in cutting efficiency of the drilling process. The results from this study also provides experimental evidence for the need to incorporate vibration induced force losses into the equation of drilling efficiency for correct estimations of rock strength downhole.
Reports on the topic "PDC bit wear"
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Glowka, D. A. Development of a method for predicting the performance and wear of PDC (polycrystalline diamond compact) drill bits. Office of Scientific and Technical Information (OSTI), September 1987. http://dx.doi.org/10.2172/5591640.
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