Heerka dhuumaha ERW waa sida soo socota: API 5L, ASTM A53 B, ASTM A178, ASTM A500/501, ASTM A691, ASTM A252, ASTM A672 API 5L Standard ujeedadeedu tahay gaasta iyo biyaha warshadaha saliidda iyo gaaska si loo tixraaco, taas oo loo isticmaalo tuubo bir ah oo aan kala go 'lahayn iyo tuubo bir ah oo welded, oo ay ku jiraan dekedda iyo dekedda caadiga ah, dekedda godka dhuunta ...
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