The difference between stainless steel welded pipe and stainless steel seamless pipe

A seamless stainless steel pipe is a long piece of steel with a hollow cross section and no seams around it.

Stainless steel welded steel pipe is also a kind of steel with a hollow cross-section, except that it is welded through the plate rolled into a steel pipe, so the welded steel pipe has a welded seam.

Stainless steel seamless pipe features

First, the thicker the wall thickness of the product, it **** is more economical and practical, the thinner the wall thickness, its processing costs **** will rise dramatically; second, the process of the product determines its limitations performance, the general seamless steel pipe precision is low: the wall thickness is not uniform, the tube inside the appearance of the brightness is low, the cost of the fixed size is high, and the inside appearance and the pockmarks, black dots is not easy to remove; third, it must be detected and shaped off-line Processing. Therefore, it reflects its superiority in high-pressure, high-strength, mechanical structure materials.

Types of stainless steel tube

The rolling method is divided into hot rolling, hot extrusion and cold drawn (rolled) Stainless Steel Pipe.

Stainless steel pipe specifications and appearance quality

A, according to GB14975-94 "stainless steel seamless steel pipe" provisions, the usual length of the steel pipe (not ruler) hot-rolled steel pipe 1.5 ~ 10m, hot extrusion steel pipe equal to and greater than 1m. cold drawn (rolled) steel pipe wall thickness of 0.5 ~ 1.0mm, 1.0 ~ 7m; wall thickness of more than 1.0mm, 1.5 ~ 8m. Stainless steel welded pipe

B. Hot rolled (hot extrusion) steel pipe diameter 54~480mm total 45 kinds; wall thickness 4.5~45mm total 36 kinds. Cold-drawn (rolled) steel pipe diameter 6~200mm total 65 kinds; wall thickness 0.5~21mm total 39 kinds.

C, the internal and external surfaces of the steel pipe shall not have cracks, folding, cracks, cracks, rolled folding, delamination and scarring defects exist, these defects should be completely removed (except for machining pipe), removal shall not make the wall thickness and outside diameter exceeds the negative deviation. Where not more than the permissible negative deviation of other minor surface defects may not be removed.

D. Allowable depth of straight channel. Hot-rolled, hot-extruded steel pipe, diameter less than and equal to 140mm is not greater than 5% of the nominal wall thickness,**** depth of not more than 0.5mm; cold-drawn (rolled) steel pipe is not greater than 4% of the nominal wall thickness,**** depth of not more than 0.3mm.

E. The ends of the steel pipe should be cut at right angles and burrs should be removed.