The main difference between seamless steel pipe and welded pipe lies in the forming process. Usually welded steel pipes, such as water pipes, are usually bent and welded together by flat plates, and then a joint can be found; the diameter is usually spiral weld. Seamless steel pipe is usually melted through annular gap and then extruded by backlog forming process, so there is no seam. In terms of performance, especially compared with welded steel, the bearing capacity is greatly improved, and is often used in high-pressure equipment. Hydraulic equipment, such as pipeline connection. Welding area of welded steel pipe is the weakest link, and welding quality is also the main factor affecting the overall performance. Welded steel pipes in the North usually burst with water pipes or heating pipes. They are usually welded in cold weather and exploded in winter.
The seamless steel pipe is perforated to produce steel. Weld the steel pipe into barrels and then weld. According to the production of seamless steel pipe and welded pipe methods are divided into two kinds. Seamless steel pipes are made of high quality carbon steel or alloy steel, hot-rolled and cold-rolled (tension) points. Welded steel sheets are rolled into tube sheets, welded seams or spiral seam welding. In manufacturing methods, they are divided into low pressure fluid welded pipe, spiral welded pipe, straight welded pipe and welded pipe. Seamless steel pipe can be used in various liquid and gas pipelines. Welded pipe can be used in water pipe, gas pipe and heating pipe. Seamless steel pipes are suitable for important applications, such as pipes, barrels, etc. uniform, high pressure. Usually high quality steel, even alloy steel is used. Generally used steel compression steel, such as water pipes, gas pipes, etc.