(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. Chemical analysis according to the ASTME59 version of the sample preparation, according to the ASTME350 version of the chemical analysis.
Steel grade of oil casing: H40, J55, K55, N80, L80, C90, T95, P110, Q125, V150, etc. Casing end processing forms: short round thread, long round thread, partial trapezoidal thread, special buckle, etc. Used for oil well drilling, mainly for supporting the well wall during the drilling process and after the completion of the well, to ensure the normal operation of the entire well after the completion of the drilling process.
[(OD – wall thickness)wall thickness]0.02466=kg/m (weight per meter)
According to the specific situation in China, roughly 62kg of oil well pipe is required for every 1m of drilling, including 48kg of casing and 10kg of tubing. 3kg of drill pipe and 0.5kg of drill collar.