Application of API 5l steel pipe: used in oil well drilling. It is mainly used in the drilling process and to support the wall after the completion of borehole so that the normal operation of oil wells during the drilling process and after the completion is to be ensured. Categories of API steel pipe: According to "petroleum casing" SY/T6194-96, API steel pipe's type and packing can be divided into short-thread casing and its coupling as well as long thread casing and its coupling. According to the provisions of the SY/T6194-96, domestic API steel pipe should be bundled up with steel wire or steel strapping. Show part of each API steel pipe and coupling thread shall be protected by ring.
Specifications and Appearance Quality of API steel pipe:
1) According to provisions of SY/T6194-96, domestic API steel pipe's length is uncertain, with the range of 8 to 13 meters. However, API steel pipe that is not less than 6 m can be provided and the amount shall not exceed 20%.
2) The internal and external surfaces of the API steel pipe shall have not been folded, hair-cracked, delaminated, cracked, rolling or scarring. These defects shall be completely removed but the remove depth shall not exceed 12.5% of the nominal wall thickness.
3) Coupling's surface cannot have the defects of being folded, hair-cracked, delaminated, cracked, rolling, scarring, etc.
4) API 5l steel pipe and its coupling thread surface should be smooth, which means that there should be no burr, tear and other defects that are able to make the thread break off and the strength of tight junction of API steel pipe is to be influenced.
API steel pipe is the lifeblood of maintaining any oil wells. Due to different geological conditions, complex underground stress state including pulling, pressing, bending, torsion stress all acts on the pipe body, which puts forward higher requirements on the quality of the pipe itself. Once the API steel pipe is damaged due to some factors, it may leads to the whole reduction in production or even scrapping of the well. Different well conditions and depths will need different grades of steel. Under corrosive environment, it also requires the pipe itself to have the ability of resisting corrosion. In the complicated geological conditions, it also calls for collapse resistance.
