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What is the Difference Between Seamless Stainless Steel Pipe and Seamed Stainless Steel Pipe?

Jun. 01, 2020

As a Seamless Steel Pipe Supplier, share with you. The manufacturing development process of seamless stainless steel pipe is to drill holes in Chinese stainless steel billets at a temperature of 2200 ° F. At this high temperature, the tool steel is softened and spirally formed in the hole after designing stamping and drawing. In this way, the wall thickness of the tube is not uniformly affected and the eccentricity is high. The wall thickness difference of the seamless pipe is larger than that of the horizontal joint pipe. Since my country's stainless steel slit pipe is made of precision cold-rolled sheet material, the tolerance of the wall thickness of the slit pipe is very small, and the wall thickness for the entire calculated circumference is very uniform.

Cold Drawn Seamless Steel Pipe

Cold Drawn Seamless Steel Pipe

Seamless stainless steel pipe and seamed stainless steel pipe have different chemical compositions. The steel components used to produce seamless pipes only meet the basic requirements of ASTM. The steel used to produce the joint contains chemicals suitable for welding. For example, silicon, sulfur, manganese, oxygen, and delta ferrite are mixed in proportion to produce a welding flux, which easily transfers heat during the welding process, so that the entire weld seam is completely fused. This kind of chemical-free steel pipe, such as seamless steel pipe, will produce various unstable elements during the welding process, making the welding hard and impermeable. Let me share the difference between seamless stainless steel pipe and seamed stainless steel pipe. :

1. Concentricity

Seamless pipes are manufactured in the stainless steel punching blank at a temperature of 2200 ° F. At this temperature, the steel is softened and formed by punching and spiral drawing at the hole cutter. Therefore, the tube wall thickness and eccentricity unevenness rate. Therefore, ASTM ensures that the wall thickness ratio of the seamless steel pipe is larger than the difference between the differences of the seam pipe. Slotted tubes are formed by precision cold-rolled sheets (4-5 feet wide per roll). Such cold-rolled sheets usually have a maximum thickness difference of 0.002. Cut the sheet to a width of πD, where d is the outer diameter of the tube. Slit tube with small thickness tolerance, and the wall thickness is very uniform throughout the circumference.

2. Welding performance

In general, the research on the chemical composition of sewing tubes and seamless tubes is somewhat different. The steel composition used in the production of seamless pipes by enterprises only meets the basic development requirements of ASTM. The steel used for production joints contains a chemically reactive substance suitable for welding itself. For example, silicon, sulfur, manganese, oxygen and delta ferrite are mixed in proportion to produce a weld flux that can easily transfer heat during welding work, so that our entire weld is fully penetrated. This kind of chemical-free steel pipe, such as seamless pipe, will produce various socially unstable elements in the welding process management, which makes the welding hard and cannot penetrate.

Our company also has Cold Drawn Seamless Steel Pipe for sale, please contact us.


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