The Difference Between Stainless Steel Welded Pipe And Stainless Steel Seamless Pipe

Stainless steel seamless steel pipe is a long steel with a hollow section and no joints on the periphery.

Stainless steel welded steel pipe is also a kind of hollow section steel, but it is welded by rolling a plate into a steel pipe, 

so the welded steel pipe has a welding gap.

Features of stainless steel seamless pipe

First, the thicker the wall thickness of the product, the more economical and practical it is, and the thinner the 

wall thickness,its processing cost will increase significantly; secondly, the process determines the product Its 

limited performance, the general seamless steel pipe has low precision: uneven wall thickness, low brightness 

inside and outside the pipe, high cost of sizing, and there are pits and black spots on the inside and outside that 

are not easy to remove; third, it must be inspected and reshaped Offline processing. Therefore, it embodies its 

superiority in terms of high-pressure, high-strength, and mechanical structural materials.

Types of stainless steel pipes

The rolling method is divided into hot rolling, hot extrusion and cold drawing (rolling) stainless steel pipe.

Stainless steel pipe specifications and appearance quality

A. According to the provisions of GB14975-94 "Stainless Steel Seamless Steel Tubes", the steel pipes usually have a

 length (indefinite length) of hot-rolled steel pipes of 1.5~10m, hot-extruded steel pipes equal to and greater than 1m. 

Cold drawn (rolled) steel pipes with a wall thickness of 0.5~1.0mm ，1.0~7m; For those with wall thickness greater 

than1.0mm, 1.5~8m. Stainless steel welded pipe

B. There are 45 kinds of hot-rolled (hot-extruded) steel pipes with a diameter of 54-480mm and 36 kinds with a wall 

thickness of 4.5-45mm. There are 65 kinds of cold drawn (rolled) steel pipes with a diameter of 6~200mm and 39 kinds 

with a wall thickness of 0.5~21mm.

C. There should be no cracks, folds, cracks, cracks, rolling,delamination and scarring on the inner and outer surfaces of the 

steel pipe. These defects should be completely removed (except for pipes for mechanical processing). 

The diameter exceeds the negative deviation. Other minor surface defects that do not exceed the allowable negative deviation 

may not be removed.

D. Allowable depth of straights. Hot-rolled and hot-extruded steel pipes, with a diameter less than and equal to 140mm, 

not more than 5% of the nominal wall thickness, and the maximum depth is not more than 0.5mm; cold drawn (rolled) steel 

pipes are not more than 4% of the nominal wall thickness,The depth is not more than 0.3mm. Stainless steel welded pipe manufacturer

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