INVESTIGATION OF MECHANICAL PROPERTIES OF PIPES WITH BUTT CURVED LAP JOINTS SUBJECTED TO TORSION

In this study, the mechanical properties of steel pipe joints bonded with an acrylic adhesive under torsion were investigated by considering different overlap lengths and curvilinear radii. For this purpose, St-37 galvanized steel pipes with ØD = 21.3 mm outer and Ød = 15.9 mm inner diameters were modeled in three dimensions by creating 8, 10, 12 mm overlapping lengths in male and female form and 30, 40 and 50 mm curvilinear radii on the forehead regions. Numerical analyzes of the created models were performed in the ANSYS Workbench program, and samples with an overlap length of 10 mm were prepared on the CNC (Computer Numerical Control) bench to verify the numerical analysis. The prepared male and female specimens were joined using an acrylic-based DP810 structural adhesive resistant to humid environments, curable at room temperature, and validation experiments were carried out. After the study, obtained numerical and experimental data showed that pipe lap joints subjected to torsional moment with the same lap length but different curvilinear radius have been observed to vary significantly in the amount of load they carry. In addition, as the overlap length increased, the amount of load they carried increased. Also, in this study was compared by performing stress analyzes according to the overlap length and radii of curvature.

Analysis of approaches for creating pipe connections in oil and gas equipment

The article deals with the problem of connecting pipelines in the oil and gas industry. One of the connection methods is resistance welding. Often, the use of this approach shows muted efficiency as it depends on the qualifications of the welder. A technique for creating flange (plane) connections with a pipe in the oil and gas industry is considered. The necessary equipment and types of welds within the considered area are considered. Thus, it is necessary to conduct a literature-patent review to find an alternative method for creating welded joints in oil and gas pipelines in order to increase the reliability of such joints and reduce the cost of production. The analysis of the subject area and the search for possible solutions to the problem posed were carried out. Various welding methods (manual electric arc, automatic submerged-arc welding, induction brazing, etc.) are considered and a comparison of the main welding methods is given, as well as the rationale for the use of electron beam welding to create such pipe joints.

Study on the Physical Properties of Split-type Iron Base Shape Memory Alloy Pipe Joint

Aiming at the leakage phenomenon of pipeline system due to corrosion and other reasons, a split type iron-based shape memory alloy pipe joint based on the button bond connection was designed for repair. This split-type pipe joint can be used for quick in-situ maintenance of pipelines without cutting off pipelines or stopping transmission without pressure relief. It is especially suitable for intensive pipeline maintenance and online emergency maintenance. In order to study the connection performance of the split iron-based shape memory alloy pipe joint, this paper took the Fe17Mn4Si10Cr4Ni alloy pipe joint as the research object, and carried out pressure sealing and pull-out experiments respectively on the integral pipe joint and the split pipe joint which had not been carried out and had been subjected to one heat and mechanical training. The results showed that, compared with the integral pipe joint, the pressure seal value of the split pipe joint decreased by 40% to 20MPa and the pulling force decreased by 48.9% without heat-mechanical training. However, after 1 time of thermal-mechanical training, the pressure sealing value of the split-type pipe joint decreased by 12.5% to 32MPa and the pulling force decreased by 21.2% compared with the integral pipe joint. It can be seen that thermal-mechanical training can significantly improve the joint performance of split pipe joints, and the split pipe joint can meet the requirements of medium and low pressure pipeline connection and maintenance.

Experimental research on improving the wear resistance and anti-friction properties of drill pipe joints

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.

Qualification of Local Stress Relief Heat Treatment of Double Submerged-Arc Welded DSAW Pipe for Reel-Lay Installation

Reel-lay installation is one of the most effective methods for subsea pipeline installation. Pipes subject to reeling installation experience cyclic plastic deformations and tight control of the yield strength range, yield strength to ultimate tensile strength ratio (YS/UTS) and uniform elongation values is required on the delivered pipe. Double Submerged-Arc Weld (DSAW) pipes formed from Thermo-Mechanically Controlled Process (TMCP) plates do not normally exhibit the minimum requirements for plastic strain requirements such as minimum YS/UTS ratio or uniform elongation values. This paper describes a process for increasing the reelability of DSAW pipes. This has been achieved by induction heating of DSAW pipe ends to normalise the mechanical properties at pipe joints. The mechanical properties of the treated section have been measured and verified against design rules for reeling, based on industry standards such as DNVGL-ST-F101 [Ref. 1] and TechnipFMC supplementary requirements. The improvement in mechanical properties is measured by comparison with the as-manufactured properties of adjacent sections. A commercial study demonstrates that the locally heat-treated DSAW pipe is a cost-effective alternative to seamless pipes for reel-lay installation.

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

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.

Augmented Reality for Pipe Thread Connection Type Training

The process of extracting oil and gas is carried out by drilling with a depth of more than 200 meters below the surface of the ground, so one steel pipe is needed to run the process. The manufacture of steel pipes for the opening process has special standards, one of which is a long pipe. To reach a depth of 200 meters below the ground level, a pipe connection is needed to reach that height. The method of connecting the pipes is called the Thread Connection Type. This method has more than 20 types of threads to be applied in pipe joints. To facilitate the discussion of the types of threads and their specifications, we need a technology that can be used interactive and mobile learning media to deliver detailed information on the type of thread. The author uses the use of Augmented Reality (AR) technology to be applied as an Android-based training media that can facilitate the existing Connection Thread along with special specifications with 3D visualization. This study aims to measure the validity and practicality of using ISO 25010 (in terms of functional suitability, performance efficiency, portability and usability) of learning media so that it is easier to understand and practical. The study consisted of two parts: 1) Validity by experts (5 experts), 2) Practicality by trainees or employees (16 participants) using the USE Questionnaire instrument. Furthermore, in application development using the Multimedia Development Life Cycle (MDLC) method as its development method. As a result, the application was declared feasible with the results of the percentage of experts Validity of 96% and Practicality by employees of 79%.