Welded steel pipe used in the blank is steel or strip, because of its different welding process is divided into furnace welded pipe, welding (resistance welding) pipe and automatic arc welding pipe. Because of the different forms of welding into straight seam welded pipe and spiral welded pipe two. Because of its end shape is divided into circular welded pipe and shaped (square, flat, etc.) welded pipe. Weld pipe because of its different materials and uses are divided into the following varieties:

GB / T3091-1993 (galvanized welded steel pipe for low pressure fluid delivery). Mainly used for conveying water, gas, air, oil and heating hot water or steam and other general lower pressure fluid and other use pipe. Its representative material Q235A grade steel.

GB / T3092-1993 (galvanized welded steel pipe for low pressure fluid delivery). Mainly used to transport water, gas, air, oil and heating hot water or steam and other general lower pressure fluid and other use of the tube. Its representative material: Q235A grade steel.

GB / T14291-1992 (Mine fluid transport welded steel pipe). Mainly used for mine pressure, drainage, shaft gas with straight seam welded steel pipe. Its representative material Q235A, B grade steel. GB / T14980-1994 (Large diameter electric pipe for low pressure fluid delivery). Mainly used for conveying water, sewage, gas, air, heating steam and other low-pressure fluid and other uses. Its representative material Q235A grade steel.

GB / T12770-1991 (stainless steel welded steel pipe for mechanical construction). Mainly used in machinery, automobiles, bicycles, furniture, hotels and hotel decoration and other mechanical parts and structural parts. Its representative material 0Cr13,1Cr17,00Cr19Ni11,1Cr18Ni9,0Cr18Ni11Nb and so on.

GB / T12771-1991 (stainless steel welded pipe for fluid delivery). Mainly used for conveying low-pressure corrosive media. Representative material is 0Cr13, 0Cr19Ni9, 00Cr19Ni11, 00Cr17, 0Cr18Ni11Nb, 0017Cr17Ni14Mo2 and so on.