Nkọwapụta a bụ ịnye ọkọlọtọ nrụpụta maka usoro pipeline iji bufee mmiri, gas na mmanụ n'ime ụlọ ọrụ mmanụ na gas.
Enwere ọkwa nkọwapụta ngwaahịa abụọ, PSL 1 na PSL 2, PSL 2 nwere ihe achọrọ maka carbon dakọtara, ịdị ike notch, ike mkpụrụ kacha na ike tensile.
Ọkwa B, X42, X46, X52, X56, X60, X65, X70 na X80.
Cangzhou Spiral Steel pipes Group co., Ltd na-enye SAWH ọkpọkọ na-ekpuchi ọkwa sitere na API B ruo X70, anyị nwetara akwụkwọ API 5L afọ gara aga ma ugbu a, ọkpọkọ ahịrị anyị na-ejikarị CNPC, CPECC maka ọrụ pipeline ha.