Basic matters of oil casing
Chemical composition(1)According to SY/T6194-96. The same steel grade is used for the casing and its coupling. Sulfur content <0.045% and phosphorus content <0.045%.(2)Take chemical analysis samples according to the provisions of GB/T222-84. Chemical analysis in accordance with the provisions of the relevant part of GB223.(3) American Petroleum Institute API SPEC 5CT 1988 1st edition regulations. […]