The production process of large-diameter welded pipe is can be divided into the 3 types:

1. Large-diameter spiral steel pipe is made by hot-rolled steel coils and welded by spiral coiling. Because it is spiral weld, so it also called spiral welded steel pipe. 

2. Large-diameter straight seam steel pipes are coiled and welded with hot-rolled steel coils and medium-thick plates. Because there is one or two straight seams on pipe, so it also called straight seam steel pipes.

The process is divided into two types: 1. double-sided submerged arc welding process, most are large-diameter thick-wall welded pipe. 2.  high-frequency welding process, mainly are small-diameter thin-wall welded pipes.

3. Large-diameter coiled pipe, using medium and thick plates as raw material, coiled with a pipe rolling machine, rounded, and then submerged arc welding process, because its welding shape is like a T-shape, it is also called a T-shaped welded pipe.

Changsha Xiangjia Metal Materical Co., Ltd. the Steel Pipe Division of ADTO GROUP, is one of the leading manufacturers of steel products in China. We specializes in manufacturing all kinds of steel pipe in various grades and sizes. Years of production experience and manufacturing facilities who have a capacity of 200,000 tons per annual will ensure the good quality and competitive duration of our products.