The quality depends on thedrill pipe drill pipe tube, fittings and welding area. Drill pipe failure is mainly fatigue fracture, corrosion fatigue and overload failure occurred mainly in the drill pipe body thickened transition zone, drill pipe joint thread and weld zone three parts. Therefore, the study and improvement of drill pipe production technology, improve quality and service life of drill pipe from the three sites are also set. In response to these problems, at home and abroad for the production of drill pipe body and joint use of specialized materials, mostly steel, specially designed steel chemical composition, such as the series AISI4137HM Cr-Mo steel, while strictly controlling metallurgical processes, increase the hardenability of steel , grain refinement to ensure that uniform microstructure and mechanical properties and excellent solderability performance, ensure uniform hardness and increase toughness of the material, to improve the fracture toughness of steel to extend fatigue crack incubation period.

The early 70s of last century,pressure welding and flash butt welding technology for repair of old and new drill pipe drill pipe manufacturing, but the two welding method of welding process parameters difficult to control, easy to weld parts for granular or block oxide and silicate inclusions remain in the weld and form deadly pits shallow micro-gray leaf spot welding defects. Gray leaf spot defects exist welded drill pipe in use easily lead to early brittle fracture, can not meet the drilling requirements, so these two welding methods have been gradually phased out.

Later, in order to meet the requirements of drilling technology to drill pipe, drill pipe of a new production technology --- the friction welding process. This welding method because the heating time short narrow heat affected zone (weld ends no more than 20mm), pressure welding seam in the top can be squeezed out harmful particles such as inclusions, so that the drill pipe welding quality greatly improved, to avoid the flash welding and other welding methods is easy to produce the harmful welding defects. Domestic drill pipe joint quality has reached the level of friction through the introduction of advanced welding and welding technology, welding performance is stable, the use of high-quality drill tube, drill pipe made completely to achieve the overall performance of the drill pipe imports performance.