Drilling Action of Roller-Cone Bits: Modeling and Experimental Validation

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
Luiz F. P. Franca
Keyword(s):  
Polycrystalline Diamond ◽  
Quantitative Information ◽  
Rock Properties ◽  
Drilling Rig ◽  
Proposed Model ◽  
Theoretical Predictions ◽  
Weight On Bit ◽  
Torque On Bit ◽  
Polycrystalline Diamond Compact ◽  
Potential Use

This paper presents a new model of the drilling response of roller-cone bits. First, a set of relations between the weight-on-bit W, the torque-on-bit T, the rate of penetration V, and the angular velocity Ω is established in the spirit of the model developed for polycrystalline diamond compact (PDC) bits. In contrast to models that depend on a precise description of the bit, the drilling response is investigated by lumping the effect of the bit geometry into a few parameters and on averaging the drilling quantities (W,T,V,Ω) over at least one revolution of the bit. Within the framework of the model, quantitative information from drilling data related to rock properties, bit conditions, and drilling efficiency can be extracted. Finally, a series of laboratory tests at atmospheric pressure conducted with an in-house designed drilling rig, together with published experimental data, is used to evaluate the proposed model. The good match between the experimental results and the theoretical predictions are promising in regard to the potential use of this model to investigate the drilling response of roller-cone bits.

Mathematical Modeling of PDC Bit Drilling Process Based on a Single-Cutter Mechanics

1993 ◽  
Vol 115 (4) ◽  
pp. 247-256 ◽  
Author(s):  
A. K. Wojtanowicz ◽  
E. Kuru
Keyword(s):  
Polycrystalline Diamond ◽  
Rock Properties ◽  
Drilling Process ◽  
Drilling Parameters ◽  
Pdc Bit ◽  
Analytical Development ◽  
Assumed Similarity ◽  
Balance Of Forces ◽  
Bit Life ◽  
Polycrystalline Diamond Compact

An analytical development of a new mechanistic drilling model for polycrystalline diamond compact (PDC) bits is presented. The derivation accounts for static balance of forces acting on a single PDC cutter and is based on assumed similarity between bit and cutter. The model is fully explicit with physical meanings given to all constants and functions. Three equations constitute the mathematical model: torque, drilling rate, and bit life. The equations comprise cutter’s geometry, rock properties drilling parameters, and four empirical constants. The constants are used to match the model to a PDC drilling process. Also presented are qualitative and predictive verifications of the model. Qualitative verification shows that the model’s response to drilling process variables is similar to the behavior of full-size PDC bits. However, accuracy of the model’s predictions of PDC bit performance is limited primarily by imprecision of bit-dull evaluation. The verification study is based upon the reported laboratory drilling and field drilling tests as well as field data collected by the authors.

Hybrid Physics-Field Data Approach Improves Prediction of ROP / Drilling Performance of Sharp and Worn PDC Bits

2021 ◽  
Author(s):  
Guodong David Zhan ◽  
Arturo Magana-Mora ◽  
Eric Moellendick ◽  
John Bomidi ◽  
Xu Huang ◽  
...  
Keyword(s):  
Prediction Models ◽  
Collaborative Study ◽  
Hybrid Approach ◽  
Polycrystalline Diamond ◽  
Rock Properties ◽  
Quantitative Prediction ◽  
Model Learning ◽  
Drilling Performance ◽  
Pdc Bit ◽  
Polycrystalline Diamond Compact

Abstract This study presents a hybrid approach that combines data-driven and physics models for worn and sharp drilling simulation of polycrystalline diamond compact (PDC) bit designs and field learning from limited downhole drilling data, worn state measurements, formation properties, and operating environment. The physics models include a drilling response model for cutting forces, worn or rubbing elements in the bit design. Decades of pressurized drilling and cutting experiments validated these models and constrained the physical behaviour while some coefficients are open for field model learning. This hybrid approach of drilling physics with data learning extends the laboratory results to application in the field. The field learning process included selecting runs in a well for which rock properties model was built. Downhole drilling measurements, known sharp bit design, and measured wear geometry were used for verification. The models derived from this collaborative study resulted in improved worn bit drilling response understanding, and quantitative prediction models, which are foundational frameworks for drilling and economics optimization.

Modeling Material Removal in Lapping of Brittle Materials

2012 ◽  
Author(s):  
Songsheng Zhou ◽  
Alex Fang
Keyword(s):  
Material Removal ◽  
Removal Rate ◽  
Applied Pressure ◽  
Polycrystalline Diamond ◽  
Current Approach ◽  
Influential Factors ◽  
Proposed Model ◽  
Modeling Material ◽  
Series Of Experiments ◽  
Polycrystalline Diamond Compact

Lapping of polycrystalline diamond compact (PDC) is a costly and time-consuming process that demands fundamental studies to improve its efficiency and quality. A series of experiments are conducted in this study to gain insights into the effects of the most influential factors on material removal rate (MRR). The well-known Preston’s equation is found to be insufficient for a satisfactory prediction of MRR associated with PDC lapping, and a new model is developed. The current approach treats MRR as the product of removal intensity and removal density, which are formulated as simple functions of pressure, velocity and grain concentration. The newly derived model is in good accordance with the analyzed experimental results. The decrease in MRR at higher pressure and the connections between applied pressure, grain concentration and MRR can all be well explained by the proposed model.

Study of the Influence of Controlled Axial Oscillations of pVARD on Generating Downhole Dynamic WOB and Improving Coring and Drilling Performance in Shale

2019 ◽  
Author(s):  
Abdelsalam N. Abugharara ◽  
John Molgaard ◽  
Charles A. Hurich ◽  
Stephen D. Butt
Keyword(s):  
Sampling Rate ◽  
Polycrystalline Diamond ◽  
Rotary Drilling ◽  
Labview Software ◽  
Drilling Performance ◽  
Drilling Parameters ◽  
Wide Range ◽  
Pdc Bit ◽  
Weight On Bit ◽  
Polycrystalline Diamond Compact

Abstract This work concentrates on the investigation of enhancing drilling performance through increasing drilling rate of penetration (ROP) by using a passive vibration assisted rotary drilling (pVARD) tool. It also involves analysis of how ROP was significantly increased when drilling using pVARD compared to drilling using conventional system “rigid” using coring and drilling in shale rocks. The apparatus used was a fully instrument laboratory scale rig and the bits were dual-cutter polycrystalline diamond compact (PDC) bit for drilling and diamond impregnated coring bit for coring. The flow rate was constant of (7 litter / min) using clean water at atmospheric pressure. In addition, for accuracy data recording, a data acquisition system (DAQ-Sys) using a LabVIEW software was utilized to record data at 1000HZ sampling rate. The output drilling parameters involved in the analysis included operational rpm, torque (TRQ), and ROP. All the output-drilling parameters were analyzed with relation to downhole dynamic weight on bit (DDWOB). The result of this work explained how pVARD can increase the DDWOB and improve ROP. The result also demonstrated generating a balanced and concentric increase in DDWOB and minimizing the wide-range fluctuation of DDWOB generated in rigid drilling, particularly at high DDWOB.

scholarly journals Optimal design of a global force-balanced polycrystalline diamond compact bit considering wear condition

2019 ◽  
Vol 11 (12) ◽  
pp. 168781401989445
Author(s):  
Yachao Ma ◽  
Zhanghua Lian ◽  
Zhiqiang Huang ◽  
Wenlin Zhang ◽  
Dou Xie
Keyword(s):  
Oil And Gas ◽  
Polycrystalline Diamond ◽  
Bending Moment ◽  
Lateral Force ◽  
Force Model ◽  
Gas Drilling ◽  
Weight On Bit ◽  
Optimal Approach ◽  
Polycrystalline Diamond Compact ◽  
Wear Condition

Polycrystalline diamond compact bits are one of the most widely used oil and gas drilling tools in the world. With wear, a large unbalanced lateral force and bending moment exist. These force and moment contribute not only to bit lateral vibration and whirl but also to wellbore tilt and enlargement, which will then cause early bit failure and low drilling efficiency. In this article, considering wear condition, a single cutter force model is proposed. Lateral force and bending moment models are constructed based on space-force theory. An optimal cutter layout model considering cutter wear is established. The matching approach for the optimal model is discussed based on Kriging surrogate model and genetic algorithm. Then, an optimization case is presented. The results show that the bit force models are in line with the actual drilling condition. The optimal approach is efficient. After optimization, the lateral force to weight on bit ratio is reduced by 10.99%, and the bending moment to torque on bit ratio is reduced by 30.43%. This result is a significant improvement in the force condition and stability of the polycrystalline diamond compact bit; ultimately, the whirl and tilt motion can be reduced, and the drilling efficiency can be improved.

Experimental Investigation of the Effect of Shale Anisotropy Orientation on the Main Drilling Parameters Influencing Oriented Drilling Performance in Shale

2019 ◽  
Vol 141 (10) ◽  
Author(s):  
A. N. Abugharara ◽  
Bashir Mohamed ◽  
C. Hurich ◽  
J. Molgaard ◽  
S. D. Butt
Keyword(s):  
Drilling Fluid ◽  
Polycrystalline Diamond ◽  
Bedding Plane ◽  
Depth Of Cut ◽  
Fine Aggregate ◽  
Drilling Rig ◽  
Drilling Performance ◽  
Bedding Planes ◽  
Weight On Bit ◽  
Shale Anisotropy

The influence of shale anisotropy and orientation on shale drilling performance was studied with an instrumented laboratory drilling rig with a 38.1-mm dual-cutter polycrystalline diamond compact (PDC) bit, operating at a nominally fixed rotational speed with a constant rate of flow of drilling fluid—water. However, the rate of rotation (rpm) was affected by the weight on bit (WOB), as was the torque (TRQ) produced. The WOB also affected the depth of cut (DOC). All these variables, WOB, rpm, TRQ, and DOC, were monitored dynamically, for example, rpm with a resolution of one-third of a revolution (samples at time intervals of 0.07 s.) The shale studied was from Newfoundland and was compared with similar tests on granite, also from a local site. Similar tests were also conducted on the concrete made with fine aggregate, used as “rock-like material” (RLM). The shale samples were embedded (laterally confined) in the concrete while drilled in directions perpendicular, parallel, and at 45 deg orientations to bedding planes. Cores were produced from all three materials in several directions for the determination of oriented physical properties derived from ultrasonic testing and oriented unconfined compressive strength (OUCS). In the case of shale, directions were set relative to the bedding. In this study, both primary (or compression) velocity Vp and shear ultrasonic velocity Vs were found to vary with orientation on the local shale samples cored parallel to bedding planes, while Vp and Vs varied, but only slightly, with orientation in tests on granite and RLM. The OUCS data for shale, published elsewhere, support the OUCS theory of this work. The OUCS is high perpendicular and parallel to shale bedding, and is low oblique to shale bedding. Correlations were found between the test parameters determined from the drilling tests on local shale. As expected, ROP, DOC, and TRQ increase with increasing WOB, while there are inverse relationships between ROP, DOC, and TRQ with rpm on the other hand. All these parameters vary with orientation to the bedding plane.

Issues in Polycrystalline Diamond Compact Cutter–Rock Interaction From a Metal Machining Point of View—Part I: Temperature, Stresses, and Forces

2012 ◽  
Vol 134 (6) ◽  
Author(s):  
Demeng Che ◽  
Peidong Han ◽  
Ping Guo ◽  
Kornel Ehmann
Keyword(s):  
Metal Cutting ◽  
Polycrystalline Diamond ◽  
Point Of View ◽  
Rock Properties ◽  
Machining Processes ◽  
Temperature Stresses ◽  
Rock Interaction ◽  
Metal Machining ◽  
Rock Interface ◽  
Polycrystalline Diamond Compact

This paper provides a comprehensive review of the literature that deals with issues surrounding the polycrystalline diamond compact (PDC) cutter–rock interface during rock cutting/drilling processes. The paper is separated into two parts addressing eight significant issues: Part I deals with fundamental issues associated with temperature/stress distribution and loading force prediction, while Part II focuses on issues related to PDC cutter/bit performance, wear and other failure phenomena, rock removal mechanism and cutting theory, rock properties, and numerical modeling of cutter–rock interaction. Experimental, analytical, and numerical methods are included into the investigation of the above-mentioned eight issues. Relevant concepts from metal cutting, micromachining, and other machining processes are also introduced to provide important insights and draw parallels between these interrelated fields.

Modeling of Cutting Rock: From PDC Cutter to PDC Bit—Modeling of PDC Bit

SPE Journal ◽  
2021 ◽  
pp. 1-23
Author(s):  
Pengju Chen ◽  
Stefan Miska ◽  
Mengjiao Yu ◽  
Evren Ozbayoglu
Keyword(s):  
Polycrystalline Diamond ◽  
Field Application ◽  
Design Parameters ◽  
Depth Of Cut ◽  
Side Force ◽  
Pdc Bit ◽  
Weight On Bit ◽  
Torque On Bit ◽  
Two Parameters ◽  
Drilling Conditions

Summary In this paper, we integrated our polycrystalline diamond compact (PDC) cutter model (Chen et al. 2021) into a PDC bit model that can predict the weight on bit (WOB), torque on bit (TOB), and imbalanced side force on a bit under given drilling conditions. We first proposed a method to determine the actual cutting plane and depth of cut of each cutter on a PDC bit. Once the two parameters for each cutter are determined, the cutter model can then be applied to calculate the cutting force of each cutter. The final bit force and moment (i.e., WOB, TOB, and imbalanced side force) are calculated as the resultant force and moment of cutting forces of all cutters. The PDC bit model in this paper considers all bit design parameters, including bit matrix geometry, blade profile, cutter layout, and the inclination of each cutter. Furthermore, the bit model also considers some bottomhole assembly (BHA) parameters (e.g., bit tilt angle, location of first fulcrum point, and tool face/steering plane angle), which allows the bit model to simulate a bit under different drilling modes. The bit model is also validated by published test data and field applications. Finally, case studies are conducted, and the influence of bottomhole stresses, BHA parameters, and drilling modes on bit force and moment are discussed. A field application of the bit model is also provided. The bit model can be directly used for PDC bit design and simulation. In fact, this paper presents a general way to integrate a cutter model into a PDC bit model. Readers are also encouraged to apply this method to integrate their own cutter model into a PDC bit model.

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