N80 is a steel-grade oil well pipe, usually made of 42MnMo7 steel.

Used for oil well drilling. According to sy/t6194-96 "Petroleum Casing", there are two types: short threaded casing and its coupling, and long threaded casing and its coupling.

N80 steel is generally oil casing.

N80 oil casing is an important equipment for oil drilling, and its main equipment includes drill pipe, core pipe and casing, drill collar and steel pipe for small-bore drilling.

The performance parameter of N80 oil casing is 0.5% elongation; The yield strength is 552--758MPa；; Tensile strength is 689MPa.

The inner and outer surfaces of the casing shall be free from folding, hairline, delamination, crack, rolling and scarring.

These defects shall be completely removed, and the removal depth shall not exceed 12.5% of the nominal wall thickness.