Welded pipe is also welded steel tubes, is a curl of a plate or strip made of welded steel pipe after molding, length 6 m. Welded steel pipe production process is simple, high production efficiency, different specifications, low investment, but the General strength of less than seamless steel tubes. Pipe can be divided into general pipe, galvanized pipe, oxygen-blown pipe, wire, metric pipe, casing rollers tube, pump tube, tube, transformer for car tube, welded thin-walled tubes, welded tube, pipe and spiral welded pipe scaffolding.

Product standards

Pipe material: Q235A,Q235C

Q235B, 16Mn, 20#, Q345, L245, L290, X42, X46, X60, X80, 0Cr13, 1Cr17, 00Cr19Ni11, and 1Cr18Ni9, and 0Cr18Ni11Nb etc.

Welded blanks are steel plates or strips, welded pipe, welding the welding process is divided into different furnace (electric resistance welded) tube and automatic electric arc welding. Because of their different form of welding is divided into straight seam welded pipe and spiral welded pipe in two ways. End because of its shape and consists of a circular pipe and shaped (square, flat) pipe. Welding because of their materials and use different and divided into several varieties:

GB/T3091-2008 (low-voltage transmission fluid used welding pipe). Mainly used for transportation of air, water, gas, heating oil and hot water or steam generally low fluid pressure and other uses, such as tubes. His representative material: Q235A steel.

GB/T14291-2006 (fluid transport welded pipe for mine). Mainly used in mine air compressor, drain, shaft straight seam welded steel pipe for gas. His representative material Q235A, grade b steel. GB/T14980-1994 (large diameter welded steel pipe for low-voltage transmission fluid). Mainly used for transportation of water, sewage, gas, low pressure air, steam for heating and other purposes. His representative material Q235A steel.

GB/T12770-2002 (stainless steel welded pipe for mechanical structure). Mainly used for machinery, automobiles, bicycles, furniture, hotel and restaurant decoration and other mechanical components and structures. His representative material 0Cr13, 1Cr17, 00Cr19Ni11, 1Cr18Ni9, 0Cr18Ni11Nb etc.

GB/T12771-1991 (fluid transport stainless steel welded pipe). Mainly used for transportation of low pressure with aggressive media. Representative material for 0Cr13, 0Cr19Ni9, 00Cr19Ni11, 00Cr17, and 0Cr18Ni11Nb, and 0017Cr17Ni14Mo2 etc.

Otherwise, welded stainless steel tubes for decoration (GB/T18705-2002), construction and decoration of stainless steel welded pipe (JG/T3030-1995), low-voltage transmission fluid with large-diameter welded steel pipe (GB/T3091-2001), as well as welded steel pipe for heat exchangers (YB4103-2000).

The production process

Longitudinal welded pipe production process is simple, high efficiency, low cost, rapid development. High strength of spiral welded pipe than longitudinal welded pipe, can narrow the billet production of large diameter welded pipes, you can use the same width of the billet production of different diameter of the pipe. But compared with the straight seam pipe of the same length, weld length 30~100%, and lower production rate.

Large diameter or thicker pipe, generally made with billet direct, and small welded thin-walled pipe takes only directly through the steel strip welded to. Then after simple polishing, drawing on it. Therefore, most small-diameter pipe used straight seam welding, large-diameter pipe is mostly used spiral welding.

Added: welding of pipe is made of steel, so it's not seamless high status.

Welding process:

Open book – flat – end of raw material cutting and welding-the loop-forming--weld bead removal – inside and outside – pre-correction--induction heat treatment--sizing and alignment – Eddy current testing – cut – water pressure check – pickling – check (strictly) – packaging – shipping.

Features

Longitudinal welded pipe production process is simple, high efficiency, low cost, rapid development. High strength of spiral welded pipe than longitudinal welded pipe, can narrow the billet production of large diameter welded pipes, you can use the same width of the billet production of different diameter of the pipe. But compared with the straight seam pipe of the same length, weld length 30~100%, and lower production rate. Therefore, most small-diameter pipe used straight seam welding, large-diameter pipe is mostly used spiral welding.

Range of application

Products are widely used in water supply engineering, petrochemical industry, chemical industry, electric power industry, agricultural irrigation, urban construction, and is one of the 20 priority product of China's development. For liquid transfer by: water supply, water drainage. Gas: gas, steam, liquid petroleum gas. Structure: piling pipe, bridge, port, road and building construction, such as.