Research on building the formula to determine the rate of penetration for polycrystalline diamond compact bits

Nowadays, polycrystalline diamond compact (PDC) drill bits are widely used in the oil and gas industry when drilling in soft rocks. However, parameters used for the PDC bit are usually based on the instructions of the drill manufacturer with a very wide adjustment range. Therefore, it is necessary to have a specific formula in order to determine the rate of penetration parameter (ROP) for the PDC bit in evaluating the influence of the parameters, rock mechanical properties and other parameters on the rate of penetration parameter (ROP). From there, it gives reasonable parameters and improves the design of the PDC bit to improve drilling efficiency. The article applies theoretical analysis method and Dalamber's principle to illuminate and build up the impact force model for PDC bits in the rock destruction process. From the impact force model, a formula to determine ROP for PDC bits was proposed. Finally, the authors applied the research results to the actual data obtained from the Nam Rong - Doi Moi oil field. The formula for determining the rate of penetration parameter (ROP) for the PDC bit that the authors have built has high accuracy and can be applied to many different rock.

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Experimental Study on Axial Impact Mitigating Stick-Slip Vibration with a PDC Bit

Shock and Vibration ◽

10.1155/2021/8897283 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Yong Wang ◽

Hongjian Ni ◽

Yiliu (Paul) Tu ◽

Ruihe Wang ◽

Xueying Wang ◽

...

Keyword(s):

Impact Force ◽

Impact Load ◽

Similarity Theory ◽

Impact Frequency ◽

Stick Slip ◽

Axial Impact ◽

Pdc Bit ◽

Fluctuation Amplitude ◽

Rotary Speed ◽

The Impact

Stick-slip vibration reduces the drilling rate of penetration, causes early wear of bits, and threatens the safety of downhole tools. Therefore, it is necessary to study suppression methods of stick-slip vibration to achieve efficient and safe drilling. Field tests show that the use of downhole axial impactors is helpful to mitigate stick-slip vibration and improve rock-breaking efficiency. However, there are many deficiencies in the study of how axial impact load affects stick-slip vibration of a PDC bit. In this paper, based on the two-degrees-of-freedom spring-mass-damper model and similarity theory, a laboratory experiment device for suppressing stick-slip vibration of a PDC bit under axial impact load has been developed, and systematic experimental research has been carried out. The results show that the axial impact force can suppress the stick-slip vibration by reducing the amplitude of weight on bit and torque fluctuations and by increasing the main frequency of torque. The amplitude of impact force affects the choice of the optimal back-rake angle. The impact frequency is negatively correlated with the fluctuation amplitude of the rotary speed. When the impact frequency is greater than 100 Hz, the fluctuation amplitude of the rotary speed will not decrease.

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An experimental and simulation study of the flow pattern characteristics of water jet impingements in boreholes

Energy Exploration & Exploitation ◽

10.1177/01445987211052063 ◽

2021 ◽

pp. 014459872110520

Author(s):

Yabin Gao ◽

Xin Xiang ◽

Ziwen Li ◽

Xiaoya Guo ◽

Peizhuang Han

Keyword(s):

High Speed ◽

Impact Force ◽

Jet Impingement ◽

Flow Patterns ◽

Water Jet ◽

Solid Boundary ◽

Force Model ◽

Water Jets ◽

Contact Surfaces ◽

The Impact

Hydraulic slotting has become one of the most common technologies adopted to increase permeability in low permeability in coal field seams. There are many factors affecting the rock breaking effects of water jets, among which the impact force cannot be ignored. To study the influencing effects of contact surface shapes on jet flow patterns and impact force, this study carried out experiments involving water jet impingement planes and boreholes under different pressure conditions. The investigations included numerical simulations under solid boundary based on gas–liquid coupling models and indoor experiments under high-speed camera observations. The results indicated that when the water jets impinged on different contact surfaces, obvious reflection flow occurred, and the axial velocity had changed through three stages during the development process. Moreover, the shapes of the contact surfaces, along with the outlet pressure, were found to have impacts on the angles and velocities of the reflected flow. The relevant empirical formulas were summarized according to this study's simulation results. In addition, the flow patterns and shapes of the contact surfaces were observed to have influencing effects on the impact force. An impact force model was established in this study based on the empirical formula, and the model was verified using both the simulation and experimental results. It was confirmed that the proposed model could provide important references for the optimization of the technical parameters water jet systems, which could provide theoretical support for the further intelligent and efficient transformation of coal mine drilling water jet technology.

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

Journal of Energy Resources Technology ◽

10.1115/1.2906429 ◽

1993 ◽

Vol 115 (4) ◽

pp. 247-256 ◽

Cited By ~ 18

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.

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Effective Formula for Impact Damping Ratio for Simulation of Earthquake-induced Structural Pounding

Geosciences ◽

10.3390/geosciences9080347 ◽

2019 ◽

Vol 9 (8) ◽

pp. 347 ◽

Cited By ~ 5

Author(s):

Seyed Mohammad Khatami ◽

Hosein Naderpour ◽

Rui Carneiro Barros ◽

Anna Jakubczyk-Gałczyńska ◽

Robert Jankowski

Keyword(s):

Kinetic Energy ◽

Impact Force ◽

Damping Ratio ◽

Dissipated Energy ◽

Force Model ◽

Single Collision ◽

Structural Pounding ◽

Impact Forces ◽

The Impact ◽

Impact Damping

Structural pounding during earthquakes may cause substantial damage to colliding structures. The phenomenon is numerically studied using different models of collisions. The aim of the present paper is to propose an effective formula for the impact damping ratio, as a parameter of the impact force model used to study different problems of structural pounding under seismic excitations. Its accuracy has been verified by four various approaches. Firstly, for the case of collisions between two structural elements, the dissipated energy during impact has been compared to the loss of kinetic energy. In the second stage of verifications, the peak impact forces during single collision have been analyzed. Then, the accuracy of different equations have been verified by comparing the impact force time histories for the situation when a concrete ball is dropped on a rigid concrete surface. Finally, pounding between two structures during earthquakes has been studied. The results of the analysis focused on comparison between dissipated and kinetic energy show relatively low errors between calculated and assumed values of the coefficient of restitution when the proposed equation is used. In addition, the results of the comparison between experimentally and numerically determined peak impact forces during single collision confirm the effectiveness of the approach. The same conclusion has been obtained for the whole impact time history for collision between a ball and a rigid surface. Finally, the results of the comparative analysis, conducted for pounding between two structures during an earthquake, confirm the simulation accuracy when the proposed approach is used. The above conclusions indicate that the proposed formula for impact damping ratio, as a parameter of impact force model for simulation of earthquake-induced structural pounding, is very effective and accurate in numerical simulations in the case of different scenarios.

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Issues in Polycrystalline Diamond Compact Cutter–Rock Interaction From a Metal Machining Point of View—Part II: Bit Performance and Rock Cutting Mechanics

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4007623 ◽

2012 ◽

Vol 134 (6) ◽

Cited By ~ 22

Author(s):

Demeng Che ◽

Peidong Han ◽

Ping Guo ◽

Kornel Ehmann

Keyword(s):

Metal Cutting ◽

Polycrystalline Diamond ◽

Rock Cutting ◽

Point Of View ◽

Rock Interaction ◽

Metal Machining ◽

Pdc Bit ◽

Rock Cutting Mechanics ◽

Cutting Processes ◽

Polycrystalline Diamond Compact

In Part I of this paper, the issues related to temperature, stress and force were reviewed and parallels were drawn between both metal machining and rock cutting. Part II discusses the issues more directly related to polycrystalline diamond compact (PDC) bit performance and rock mechanics. However, relevant issues in various metal cutting processes will continue to be presented to clarify the gaps and similarities between these two classes of processes.

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Simulation and Experimental Study of the Rock Breaking Mechanism of Personalized Polycrystalline Diamond Compact Bits

Journal of Engineering Science and Technology Review ◽

10.25103/jestr.135.16 ◽

2020 ◽

Vol 13 (5) ◽

pp. 122-131

Author(s):

Yu Jinping ◽

◽

Zou Deyong ◽

Sun Yuanxiu ◽

Zhang Yin

Keyword(s):

Experimental Study ◽

Finite Element ◽

Tensile Stress ◽

Crack Propagation ◽

Tangential Force ◽

Polycrystalline Diamond ◽

Rock Breaking ◽

Pdc Bit ◽

Breaking Mechanism ◽

Polycrystalline Diamond Compact

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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First Application of Hybrid Bit Technology to Optimize Drilling Through S Shape Directional Section with High Chert Content in UAE Land Operations

10.2118/208120-ms ◽

2021 ◽

Author(s):

Ygnacio Jesus Nunez ◽

Munir Bashir ◽

Fernando Ruiz ◽

Rakesh Kumar ◽

Mohamed Sameer ◽

...

Keyword(s):

Good Condition ◽

Polycrystalline Diamond ◽

Steering System ◽

Directional Drilling ◽

Main Challenge ◽

Drilling Parameters ◽

Pdc Bit ◽

Heterogeneous Formation ◽

Polycrystalline Diamond Compact ◽

Cutting Mechanisms

Abstract This paper highlights the solution, execution, and evaluation of the first 12.25″ application of hybrid bit on rotary steerable system in S-Shape directional application to drill interbedded formations with up to 25 % chert content in UAE land operations. The main challenge that the solution overcame is to drill through the hard chert layers while avoiding trips due to PDC bit damage nor drilling hour's limitation of TCI bit while improving the overall ROP and achieving the directional requirement. The solution package has demonstrated a superior ROP over rollercone bits, as well as improved PDC cutter durability and lower reactive torque leading to better steerability and stability which will be detailed in this paper. A significant contributor to such success was utilizing a new hybrid bit technology which incorporates the dual cutting mechanisms of both polycrystalline Diamond Compact (PDC) and rollercone bits. This allows a more efficient drilling by bringing the durability of the crushing action of rollercone to drill through hard interbedded lithology and the effectiveness of the shearing action of PDC cutters to improve ROP without sacrificing the toughness of the cutting structure edge. The proposed solution in combined with continues proportional rotary steering system managed to drill 4,670 ft through heterogeneous formation with chert nodules, with an average ROP of 38.29 ft\hr improving ROP by 15% and eliminating extra trips of utilizing roller cone bits to be able to drill though the chert nodules and avoid the PDC bit damage. Leading reduction in cost per foot by 35 %. Additionally, the hybrid bit exceed the expectation achieving 878 thousand of revolutions, with effective bearing and with the drilling cutting structure in a very good condition. Furthermore, the directional objectives were met with high quality directional drilling avoiding wellbore tortuosity. Such success was established through application analysis, specific formations drilling roadmaps and optimized drilling parameters in order to improve the overall run efficiency. The combination of roller cone and PDC elements in a hybrid bit designed to deliver better efficiency and torque stability significantly increased performance drilling the section in one single run, proven that heterogeneous formations can be drill.

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

10.2523/iptc-21457-ms ◽

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.

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Fragmentation Characteristics of Rocks Under Indentation by a Single Polycrystalline Diamond Compact Cutter

Journal of Energy Resources Technology ◽

10.1115/1.4050340 ◽

2021 ◽

Vol 143 (10) ◽

Author(s):

Zhaosheng Ji ◽

Huaizhong Shi ◽

Xianwei Dai ◽

Hengyu Song ◽

Gensheng Li ◽

...

Keyword(s):

Contact Force ◽

Brittle Failure ◽

Failure Modes ◽

Polycrystalline Diamond ◽

Rake Angle ◽

Von Mises Stress ◽

Rock Interaction ◽

Initiation Point ◽

Pdc Bit ◽

Polycrystalline Diamond Compact

Abstract Polycrystalline diamond compact (PDC) bit accounts for the most drilling footage in the development of deep and geothermal resources. The goal of this paper is to investigate the PDC cutter-rock interaction and reveal the rock fragmentation mechanism. A series of loading and unloading tests are conducted to obtain the curves of contact force versus penetration displacement. A single practical PDC cutter is fixed on the designed clamping devices that are mounted on the servo experiment system TAW-1000 in the tests. The craters morphology and quantified data were obtained by scanning the fragmented rock specimen using a three-dimensional morphology scanner. Finally, a numerical model is established to get the stress and deformation fields of the rock under a single PDC cutter. The results show that there are two kinds of failure modes, i.e., brittle failure and plastic failure, in the loading process. Marble is more prone to brittle fracture and has the lowest specific energy, followed by shale and granite. The brittle failure in marble mainly occurs behind the cutter while that happens ahead of the cutter for shale. Curves of contact force versus penetration displacement illustrate that a cutter with a back rake angle of 40 deg has a better penetration result than that with a back rake angle of 30 deg. Enhancing loading speed has a positive effect on brittle fragmentation. The distribution of von Mises stress indicates the initiation point and direction, which has a good agreement with the experiment. The research is of great significance for optimizing the PDC bit design and increasing the rate of penetration.

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Dynamic characteristics of mistuned bladed disk system under rub-impact force

Advances in Mechanical Engineering ◽

10.1177/1687814020973064 ◽

2020 ◽

Vol 12 (11) ◽

pp. 168781402097306

Author(s):

Hui Zhang ◽

Tianyu Zhao ◽

Hongyuan Zhang ◽

Honggang Pan ◽

Huiqun Yuan

Keyword(s):

Finite Element ◽

Variable Thickness ◽

Impact Force ◽

Element Model ◽

Force Model ◽

Disk System ◽

Element Analysis ◽

Bladed Disk ◽

Blade Tip ◽

The Impact

In order to study the rubbing of the mistuned bladed disk system with variable thickness blades, an elastically supported shaft-variable thickness blades coupled finite element model is established in this paper. A new rubbing force model is proposed considering the variable thickness section characteristics and rotation effect of the variable thickness blade. A method of mistuned parameter identification is introduced which consists of static frequency testing of blades, dichotomy, and finite element analysis. Based on the finite element method, the mistuned bladed disk system is made dynamic analysis in full rubbing by applying the judgment load method. The dynamic response of the mistuned bladed disk system is discussed under different conditions. The results show that increasing the amount of mistuning will increase the system vibration. At high speeds, the impact force will be partially offset by centrifugal force. And the rubbing gap affects the form of rubbing. With the gap decreases, the system will change from intermittent rubbing to continuous rubbing. In addition, when the system is rubbed, due to energy dissipation and blade damping, the stress is transferred from the blade tip to the blade root and attenuated. In general, rubbing is a random complex nonlinear vibration process.

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