scholarly journals Modeling and Experimental Study on Motion States of Laboratory-Scale Bottom Hole Assembly in Horizontal Wells

Energies ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 925
Author(s):  
Wei Li ◽  
Genlu Huang ◽  
Hongjian Ni ◽  
Fan Yu ◽  
Wu Jiang
Keyword(s):  
Numerical Simulation ◽  
Similarity Criterion ◽  
Horizontal Wells ◽  
Circular Motion ◽  
Rotary Drilling ◽  
Circular Arc ◽  
Bottom Hole ◽  
Drilling Engineering ◽  
Bottom Hole Assembly ◽  
Simulation Results

Motion states of bottom hole assembly (BHA) have a great effect on the trajectory control and drilling efficiency while rotary drilling. In order to study the motion states of BHA in horizontal wells, a BHA dynamic model with the finite element method was established. Meanwhile, an indoor experimental setup based on similarity criterion was designed and built to verify the numerical simulation results. Finally, the effects of measuring positions, rotate speeds, weight on bit (WOB), and friction coefficients on the motion states were analyzed in numerical simulation and experiment. The results show that the experimental results can match well with the numerical simulation results. The motion states of BHA in horizontal wells can be divided into three kinds, including circular arc swing, "8" shape swing, and dot-like circular motion. The circular arc swing mainly appears at middle section of BHA and occurs through the collective result of gravity and tangential friction. The dot-like circular motion mainly appears at near-bit or near-stabilizer area because drill bit and stabilizer can steady the BHA at the center part of the wellbore. The "8" shape swing mainly appears at the crossed area and occurs through collective disturbance of the other two motions. Moreover, rotate speed and friction coefficient have promotions on the lateral vibration while WOB have a much smaller effect. Through analyses, related suggestions are given for the drilling engineering. The related conclusions and suggestions in this paper can help to further understand the lateral dynamic characteristics of BHA in horizontal wells and select suitable parameters for drilling engineering.

Application Of Tandem Rotary Steerable-Positive Displacement Motor Bottom Hole Assembly In Drilling Horizontal Wells: Case Study Of Three East Siberia Wells

2011 ◽  
Author(s):  
Zimuzor Michael Okafor ◽  
Andrew John Buchan ◽  
Dmitry Diyanov ◽  
Sheldon Andre Rawlins ◽  
Grigoriy Zhadan ◽  
...  
Keyword(s):  
Horizontal Wells ◽  
East Siberia ◽  
Positive Displacement ◽  
Bottom Hole ◽  
Bottom Hole Assembly

scholarly journals The Influence of the Bottom Hole of Cold Extruding Internal Thread on Thread Quality

Mechanika ◽  
2021 ◽  
Vol 27 (4) ◽  
pp. 335-341
Author(s):  
Hongling Hou ◽  
Xin CHEN ◽  
Yongqiang ZHAO ◽  
Yayin HE ◽  
Changqian WANG
Keyword(s):  
Numerical Simulation ◽  
Extrusion Process ◽  
High Rate ◽  
Cold Extrusion ◽  
Internal Thread ◽  
Important Indicator ◽  
Good Surface ◽  
Bottom Hole ◽  
Simulation Results ◽  
The Relationship

The diameter of the threaded bottom hole determines whether the extrusion can proceed smoothly and the fullness of the tooth shape after extrusion. The tooth height rate is an important indicator of the strength of the threaded connection. In order to establish the relationship between the diameter of the bottom hole and the tooth height of the extruded internal thread, this paper takes the aluminum alloy M8×1.25 mm internal thread as an example, and uses a method of combining numerical simulation and process test. Obtained the changing law of internal thread profile and tooth height rate of extruded workpieces with different bottom hole diameters. Using MATLAB to fit the numerical simulation results, the relationship between the tooth height of the internal thread and the diameter of the prefabricated bottom hole of the workpiece was obtained. The reliability of the numerical simulation results and the feasibility of the fitting formula are verified through experiments. The results show that the diameter of the prefabricated bottom hole of the workpiece is controlled within 7.33~7.39 mm when the M8×1.25 mm internal thread is processed by the cold extrusion process. The high rate of the internal thread after extrusion meets the requirements of thread connection strength, and the internal thread has high forming quality and good surface quality.

scholarly journals Applying modern technologies when drilling directional wells with long horizontal boreholes

2020 ◽  
pp. 13-18
Author(s):  
Kuriachii Aleksandr ◽  
◽  
Kaliagin Sergei ◽  
Keyword(s):  
Horizontal Wells ◽  
Economic Advantage ◽  
Directional Drilling ◽  
Skew Angle ◽  
Service Companies ◽  
Bottom Hole ◽  
Geological Conditions ◽  
Bottom Hole Assembly ◽  
The Given ◽  
Modern Technologies

Introduction. Directional drilling of wells is currently carried out by a rotary steerable system and conventional equipment including a mud motor with an adjustable skew angle. Either of the two methods has particular advantages. Research aim is to analyze the technologies provided by various service companies in the field of directional and horizontal wells drilling in order to provide means of improving the utilization capacity of the conventional bottom hole assembly in long horizontal boreholes. Methodology. When drilling directional wells with a small departure from the vertical and wells with horizontal boreholes up to 500 m long, a preference is given to a mud motor as far as a change in deviation parameters is concerned. This is due to the fact that the mud motor has a significant economic advantage. However, when drilling directional well with complex planned profile or a well with a horizontal borehole of more than 500 m, the mud motor may cause a variety of problems, while a rotary steerable system will allow to avoid some of them. Results. The rotary steerable system is not always economically feasible suggesting a need for an alternative technology with a more advantageous offer on the market of services. A system of pulsed controlled drilling will allow the adjustment of the trajectory of the wellbore when drilling in a rotary mode with conventional equipment for directional drilling, reduce rig time, and improve the borehole quality. Summary. The given technology will make it possible to improve the efficiency of conventional equipment which includes the mud motor for directional wells drilling with complex planned profile and long horizontal boreholes of more than 500 m, as soon as the technology provides the possibility of adjusting the trajectory in a rotary mode. The system of pulsed controlled drilling is developed as an alternative to the rotary steerable system making it possible to significantly reduce construction expenses for wells with complex geological conditions of drilling

scholarly journals Numerical Modeling of Dynamic Behavior and Steering Ability of a Bottom Hole Assembly with a Bent-Housing Positive Displacement Motor Under Rotary Drilling Conditions

Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2568 ◽  
Author(s):  
Yingjie Chen ◽  
Jianhong Fu ◽  
Tianshou Ma ◽  
Anping Tong ◽  
Zhaoxue Guo ◽  
...  
Keyword(s):  
Dynamic Stress ◽  
Impact Force ◽  
Axial Loading ◽  
Drill Bit ◽  
Deviation Angle ◽  
Rotary Drilling ◽  
Positive Displacement ◽  
Bottom Hole ◽  
Bottom Hole Assembly ◽  
The Impact

Fully rotary drilling is one of many useful technologies used for the exploitation of petroleum and geothermal resources, but fully rotating drill-strings are extremely complicated. Therefore, according to the Hamilton principle, a non-linear coupled bottom hole assembly (BHA)-bit-formation-wellbore model is proposed for BHAs with bent-housing positive displacement motor using the finite element method to investigate the dynamic behavior and steering ability under fully rotary drilling. The impact force, acceleration, axial loading, torque, and dynamic stress were simulated, and factors influencing the dynamic steering forces were investigated. The results indicate that the impact force, acceleration, axial loading, torque, and dynamic stress under fully rotary drilling are much higher than under conventional drilling. The numerical simulation and field test in well B confirmed that the rotation of the drill-string is conducive to the hold-on of the deviation angle. With the increase in the weight-on-bit, bend angle, and stabilizer height, the deflecting force on a drill bit increases. Conversely, with the increase in stabilizer diameter, the deflecting force on the drill bit decreases; the lower the deflecting force, the better the effectiveness of hold-on. With increasing deviation angle, the deflecting force on the drill bit first decreases and then increases. The present model can provide a theoretical basis for wellbore trajectory control and optimization design of BHA.

Investigation on Effect of Downhole Vibration Force on Drilling Performance With a Dynamic BHA Model

2015 ◽  
Author(s):  
Lei Wang ◽  
Jianming Yang ◽  
Stephen Butt ◽  
Hongyuan Qiu
Keyword(s):  
Finite Element Method ◽  
Angular Frequency ◽  
Mean Value ◽  
Rock Interaction ◽  
Drilling Performance ◽  
Bottom Hole ◽  
Bottom Hole Assembly ◽  
The Mean ◽  
Simulation Results ◽  
Force Excitation

A dynamic bottom hole assembly (BHA) model is built with finite element method (FEM) in this paper. This model is used for evaluation the influence of externally added vibration to the BHA system. With this dynamic model along with a general bit-rock interaction formula, the BHA’s motion in axial and torsional directions are examined. Parametric study is carried out by varying the parameters of the applied vibration force, including the mean value, amplitude, angular frequency, and the location of this force excitation. The simulation results indicate that externally applied vibration force is indeed able to improve drilling performance. In particular, the mean value and amplitude of the applied force have a almost linear relation with ROP and WOB. The stresses distributions along BHA are investigated as well.

scholarly journals Dynamic Analysis of Bottom Hole Assembly With External Vibrating Force Excitation

2013 ◽  
Author(s):  
Lei Wang ◽  
Stephen Butt ◽  
Jianming Yang
Keyword(s):  
Cfd Simulation ◽  
Model Simulation ◽  
Fluid Pressure ◽  
Rock Interaction ◽  
Bottom Hole ◽  
Bottom Hole Assembly ◽  
Computational Fluid Dynamics Cfd ◽  
Simulation Results ◽  
Force Excitation ◽  
Valve Part

Based on the Downhole Oscillating Device (DOD) newly developed for purpose of improving drilling efficiency, Computational Fluid Dynamics (CFD) simulation is conducted. The axial vibration force created by the DOD is thoroughly investigated. The simulation is focused on the valve part which generates the fluid pressure pulsations. Fluid flow rate and/or back pressure is applied to the model as boundary conditions. The DOD’s application will also induce the inertia phenomenon of the fluid column above the tool. This phenomenon is also studied based on parametric analysis. Within the simulation results, a dynamic model is developed to further investigate the effect of the oscillating force generated by the DOD on drilling efficiency. Nonlinearities in the bit-rock interaction are taken into account in the model. Simulation results show that application of the DOD in drilling may improve the ROP at least by 5%.

Avalanche Features in Silicon Schottky-FETs in Accordance with Numerical Simulation Results

2006 ◽  
Vol 65 (16) ◽  
pp. 1533-1546
Author(s):  
Yu. Ye. Gordienko ◽  
S. A. Zuev ◽  
V. V. Starostenko ◽  
V. Yu. Tereshchenko ◽  
A. A. Shadrin
Keyword(s):  
Numerical Simulation ◽  
Simulation Results
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