Study on mechanical behaviors of double shoulder drill pipe joint thread

Purpose The purpose of this study is to solve the oil drill pipe joints and casing excessive wear problems and to improve the drill pipe joint-casing wear resistance and anti-friction properties. Design/methodology/approach On the surface of the drill pipe joints using oxyacetylene flame bead weld (BW) wear-resistant welding wire ARNCO-100XTTM prepares welding layer, high-velocity oxygen fuel (HVOF) Cr3C275-NiCr25 prepares coating and subsonic flame spray and remelt (SFSR) Ni60 prepares coating, then comparing and analyzing the friction and wear of the three types of wear-resistant layers and the casing under the condition of 1.8 g/cm3 mud drilling fluid lubrication. The wear resistance and anti-friction performance of the drill pipe joints were evaluated based on the wear situation, finally revealing its friction and wear mechanisms. Findings Three types of wear-resistant layers can improve the surface wear resistance of drill pipe joints, the wear-resistant layer and the substrate are well combined and the welding layers and coating are both dense and uniform. The wear resistance of the HVOF-Cr3C275-NiCr25 coating is 10.9 times that of the BW-ARNCO-100XTTM weld layer, and the wear resistance of the SFSR-Ni60 weld layer is 2.45 times that of the BW-ARNCO-100XTTM weld layer. The anti-friction properties of SFSR-Ni60 welding layer is the best, followed by HVOF-Cr3C275-NiCr25 coating, and the anti-friction properties of BW-ARNCO-100XTTM welding layer is the worst among the three. Originality/value The research results of this paper have great practical value in the process and material of improving the wear resistance and anti-friction performance of the drill pipe joint casing.

Download Full-text

Corrosion and Wear Behavior of WC–10Co4Cr Coating under Saturated Salt Drilling Fluid

Materials ◽

10.3390/ma14237379 ◽

2021 ◽

Vol 14 (23) ◽

pp. 7379

Author(s):

Hao Yin ◽

Jian Liang ◽

Xiaoyong Ren ◽

Jie Zhao ◽

Xin He ◽

...

Keyword(s):

Wear Resistance ◽

Corrosion Potential ◽

Erosion Resistance ◽

Wear Behavior ◽

Drilling Fluid ◽

Drill Pipe ◽

Corrosion Current ◽

Corrosion And Wear ◽

Simulation Results ◽

Pipe Joint

Coating on the surface is one of the main ways to improve the corrosion resistance and wear resistance of materials. In this work, the corrosion, erosion, and wear resistance of WC–10Co4Cr coating and 27CrMoV substrate were compared by simulating the actual working conditions of the drill pipe. The simulation results show that the most serious corrosion occurred at the pipe body and the dominating erosion arose at the pipe joint closing to the inlet of the flow field. WC–10Co4Cr coating has excellent protection to 27CrMoV substrate, resulting in a 400 mV increase in corrosion potential, a two-orders-of-magnitude decrease in the corrosion current, and four times the improvement of the impedance value. The erosion resistance of the WC–10Co4Cr coating increased to more than 30% higher than that of the 27CrMoV substrate. The friction coefficient of the WC–10Co4Cr coating was much lower than that of the 27CrMoV substrate, and the wear resistance of the coating was higher than that of the substrate.

Download Full-text

Design and Performance Research of Flexible Drill Pipe Joint Based on Bionic Theory

Geofluids ◽

10.1155/2021/9661388 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Chuanliu Wang ◽

Pei Ju

Keyword(s):

Flow Field ◽

Mechanical Performance ◽

Mechanical Test ◽

Drilling Fluid ◽

Fluid Velocity ◽

Drill Pipe ◽

Transmission Function ◽

Study Results ◽

Pipe Joints ◽

Pipe Joint

Fatigue fracture is the main failure form of mining drill pipe joints, which directly leads to the occurrence of drill pipe drop accidents. Based on the principle of engineering bionics, the spine structure and kinematic behavior characteristics of cheetah were studied; the bionic design and trial production of drill pipe joints were carried out. For the bionic drill pipe joint, it separates the torsion transmission function from the connection function, and when the torsion transmission function of the joint fails, the connection function is still effective, so as to achieve the effect of “breaking the bones and connecting the ribs.” The mechanical and flow field properties of the bionic drill pipe joint were analyzed. Mechanical test results showed that, for the bionic drill pipe joint, the average tensile capacity was 555.48 kN and the average torsion capacity was 8914.13 N·m, which met the mechanical performance requirements. The flow field numerical simulation results showed that, when the drilling fluid velocity field and pressure field were stable and change evenly, there is no risk of leakage. The study results can provide a new research idea for the research and development of mine drill pipe joint with long life and antidropping function.

Download Full-text

Research on the mechanism of the influence of flooding on the killing of empty wells

Journal of Petroleum Exploration and Production Technology ◽

10.1007/s13202-021-01265-4 ◽

2021 ◽

Vol 11 (9) ◽

pp. 3571-3598

Author(s):

Jie Zhang ◽

Zaipeng Zhao ◽

Xin Li ◽

Yundong Zheng ◽

Cuinan Li ◽

...

Keyword(s):

Surface Tension ◽

Droplet Diameter ◽

Drill Pipe ◽

Outer Diameter ◽

Fluid Viscosity ◽

Replacement Method ◽

Dynamic Replacement ◽

Calculation Results ◽

Casing Pressure ◽

Pipe Joint

AbstractIn empty well killing, in order to save the time and cost of killing the well, the dynamic replacement method is often used to kill the well. The main problem of the dynamic replacement method for killing wells is how to avoid terrible working conditions caused by flooding, such as gas carrying fluid, killing fluid being brought to the wellhead. Based on the principle of flooding formation and the basic tenets of flooding correlation experiment and dynamic replacement method, this paper incorporates the kill fluid viscosity, surface tension, droplet diameter, inclination angle, drill pipe joint outer diameter, and drill pipe eccentricity into the calculation range and establishes a new mathematical model suitable for dynamic replacement kill. Based on the calculation results, the influencing factors of flooding are analyzed, and the following conclusions are drawn: the increase of dynamic viscosity, gas density in the well, casing pressure, well angle, the outside diameter of drill pipe, the outer diameter of drill pipe joint, and eccentricity of drill pipe can promote the occurrence of flooding; The increase of surface tension, well-killing fluid density, and casing inner diameter have an obstacle to flooding.

Download Full-text

Analysis of Operability Envelopes for Subsea Production Tree Installation

10.20944/preprints201906.0148.v1 ◽

2019 ◽

Author(s):

Fei Wang ◽

Neng Chen

Keyword(s):

Mathematical Model ◽

Drill Pipe ◽

Differential Method ◽

Ocean Current ◽

Mechanical Behaviors ◽

Governing Equations ◽

Operation Conditions ◽

Current Water ◽

Ocean Conditions ◽

Finite Differential Method

The article presents a mathematical model to investigate the operability envelopes for subsea production tress (SPT) installation using drill pipe. The finite differential method was used to solve the established governing equations in which the ocean conditions were considered. Based on the evaluations of the ocean wave, ocean current, water depth, specification of drill pipe and SPT weight that might dominate the mechanical behaviors of the pipe, the operability envelopes with permissible ocean conditions for SPT installation were obtained. The results indicate that changes of depths in deep water and SPT weight have few effects on the operation conditions and it would be better to choose smaller pipe to obtain larger permissible ocean conditions during SPT installation.

Download Full-text

Differential Screw Pipe Joint

Scientific American ◽

10.1038/scientificamerican07141877-1272bsupp ◽

1877 ◽

Vol 4 (80supp) ◽

pp. 1272-1272

Keyword(s):

Pipe Joint

Download Full-text

The use of the spatial characteristics technique with the view of estimating the explosion wave impact on the stuck drilling string zone / Wykorzystanie techniki charakterystyk przestrzennych do określania wpływu fali uderzeniowej na przychwyconą kolumnę przewodów wiertniczych

Archives of Mining Sciences ◽

10.2478/v10267-012-0038-x ◽

2012 ◽

Vol 57 (3) ◽

pp. 601-618 ◽

Cited By ~ 3

Author(s):

Vasyl Moisyshyn ◽

Vasyl Yacyshyn ◽

Oleg Vytyaz

Keyword(s):

Drill Pipe ◽

Charge Weight ◽

Practical Implementation ◽

Problem Solution ◽

Wave Impact ◽

Spatial Characteristics ◽

Explosion Wave ◽

Deformation State ◽

Drilling String ◽

Threaded Joints

Abstract Studied here are the results of the asymmetric problem solution of the thick walled circular cylinder elasticity using the spatial characteristics technique. The practical implementation of the solution of the problem is based on the calculation of the stress-caused deformation state of the stuck drilling string zone affected by the explosion wave action upon the inner wall of the pipe. Suggested here is the technique for determining axual σz and circular σθ stress on the drill pipe wall as well as the radial displacements ur of the stuck drill pipe outer surface under the action of the explosion shock wave. The above technique enables to make a sound selection of the cylindrical explosive charge weight in order to avoid the residual strain during the drilling string shaping off and uncoupling the threaded joints or to prevent them from exceeding the admissible level.

Download Full-text