Tilmaamahani waa in la bixiyo heerka wax soo saarka ee nidaamka dhuumaha si loo gudbiyo biyaha, gaaska iyo saliidda warshadaha saliidda iyo gaaska dabiiciga ah.
Waxaa jira laba heer oo kala soocida badeecada, PSL 1 iyo PSL 2, PSL 2 waxay leedahay shuruudo qasab ah oo u dhigma kaarboonka, adkaanta darajada, xoogga waxsoosaarka ugu badan iyo xoogga xajinta.
Fasalka B, X42, X46, X52, X56, X60, X65, X70 iyo X80.
Cangzhou Spiral Steel tubes group co., Ltd sahayda tuubooyinka SAWH daboolaya fasalka API B ilaa X70, waxaan helnay API 5L shahaadada sanado ka hor iyo hadda tuubooyinka line our si ballaaran loo isticmaalo by CNPC, CPECC mashaariicda dhuumaha ay.