According to American Petroleum Institute standard APISPEC5CT1988 1st edition, casing steel grades H-40, J-55, K-55, N-80, C-75, L-80, C-90, C-95, P- 110. There are 10 kinds of Q-125. The casing shall be supplied with threads and couplings, or in any of the following pipe end forms: plain end, round thread without coupling or with coupling, buttress thread with coupling or without coupling, direct connection Type thread, special end processing, sealing ring structure.
Origin
(1) The main importing countries of petroleum casing are Germany, Japan, Romania, the Czech Republic, Italy, the United Kingdom, Austria, Switzerland, the United States, Argentina, and Singapore. Import standards mostly refer to American Petroleum Institute standards API5A, 5AX, and 5AC. The steel grades are H-40, J-55, N-80, P-110, C-75, C-95, etc. The specifications are mainly 139.77.72R-2, 177.89.19R-2, 244.58.94R-2, 244.510.03R-2, 244.511.05R-2, etc.
(2) There are three types of lengths specified by API: R-1 is 4.88~7.62m, R-2 is 7.62~10.36m, and R-3 is 10.36m or longer.
(3) Some imported goods are marked with the word LTC, that is, long threaded sleeves.
(4) In addition to API standards imported from Japan, there are a small number of Japanese manufacturers’ standards (such as Nippon Steel, Sumitomo, Kawasaki, etc.), steel grades are NC-55E, NC-80E, NC-L80, NC-80HE, etc.
(5) In previous claims cases, there have been appearance defects such as black buckle and thread damage, pipe body folding, broken buckle, and thread close distance out of tolerance, coupling J value out of tolerance, and casing brittle crack and low yield strength. and other internal quality problems.
Package
According to SY/T6194-96, the domestic casing should be bundled with steel wire or a steel belt. A protection ring shall be screwed on the exposed portion of each casing and coupling thread to protect the thread.
Post time: Aug-11-2022