N80 steel pipe

N80 steel pipe is generally a casing. N80 casing is an important equipment for oil drilling. Its main equipment also includes drill pipe, core pipe and casing, drill collar and small diameter drilling pipe.


Domestic casing is made of hot rolled or cold drawn steel by geological drilling. Steel and "Geology" (DZ) indicate that commonly used casing steels have DZ40, DZ55, DZ753 and other varieties.
(1) the main importing countries: Germany, Japan, Romania, Czech, Italy, Britain, Austria, Switzerland, the United States, Argentina, Singapore and so on. The import standards refer to the American Petroleum Association standard API5A, 5AX, 5AC. The steel grades are H-40, J-55, N-80, P-110, C-75, C-95 and so on. The main specifications are 139.77.72R2177.89.19R-2244.58.94R-2244.510.03R-2244.511.05R-2.


(2) the length of 3:R-1 provided by API is 4.88 ~ 7.62m, R-2 is 7.62 ~ 10.36m, R-3 is 10.36m.


(3) some imported goods are marked "LTC", that is, long sleeves.


(4) as the new Japan Railway, Sumitomo, Kawasaki and so on, the steel numbers are NC-55E, NC-80E, NC-L80, NC-80E, NC-80HE and so on.


(5) in the case of the claim, there are defects such as black buckle, thread damage, pipe break, break and thread distance tolerance, defects such as J value defect and brittle fracture of casing, and low yield strength quality.