Raws li ib qho tseem ceeb ntawm cov khoom siv hlau, cov kav hlau steel tau muab faib ua ob pawg: seamless steel kav (round billets) thiab welded steel kav (phaj, strip billets) vim lawv cov txheej txheem tsim khoom sib txawv thiab cov duab ntawm cov yeeb nkab blanks siv.
Seamless steel kav muab faib ua ob hom: kub dov (extruded) seamless steel kav thiab txias-draw (dov) seamless steel kav vim muaj ntau yam kev tsim khoom. Cov kav dej txias tau muab faib ua cov kav dej thiab cov kav dej tshwj xeeb. Kub dov (extruded seamless steel yeeb nkab): round tube dawb paug → cua sov → perforation → peb-yob cross dov, nruam dov los yog extrusion → raj tshem tawm → sizing (los yog txoj kab uas hla) → txias → billet raj → straightening → zoo soj ntsuam phab ntsa thickness → Hydrostatic test (los yog qhov tsis zoo) → kos npe → cia.
Cold drawn (dov) seamless steel yeeb nkab: round tube dawb paug → cua sov → perforation → taub hau → annealing → pickling → oiling (tooj liab plating) → multi-pass txias drawing (txias dov) → billet raj → tshav kub kho → straightening → zoo soj ntsuam ntawm phab ntsa thickness → hydrostatic test (tsis pom kev) → marking → cia. GB/T8162-2008 (cov yeeb nkab steel seamless rau kev siv cov qauv). Feem ntau yog siv rau cov qauv dav dav thiab cov qauv siv tshuab. Nws cov ntaub ntawv sawv cev (qib): carbon steel No. 20, No. 45 steel; alloy steel Q345, 20Cr, 40Cr, 20CrMo, 30-35CrMo, 42CrMo, thiab lwm yam.
