2. The pressure of the seamless pipe is higher, the welded pipe is generally about 10 MPa, and now the welded pipe has been seamlessly processed. The seamless steel pipe is perforated with a solid round pipe. Without a gap, the welded pipe is a steel pipe made by welding a steel plate or a strip steel after being crimped and formed, and has a slit. In general, seamless pipes can withstand greater pressure.
3. Seamless steel pipe is formed at one time during rolling. Welded steel pipes need to be welded after rolling, generally with spiral welding and straight welding. Compared to performance, the seamless tube is better, and of course the price is higher.
4. The welded pipe is generally completed by cold rolling, high frequency welding, forming and other processes. It is a kind of seamed tube. The seamless steel pipe is divided into a hot rolled pipe and a cold drawn pipe, and the hot rolled pipe is processed by blank forging, piercing, rolling, shaping, and the like. Generally, large-diameter, thick-walled seamless pipes are used in this form; cold-drawn pipes are cold-drawn by tube blanks, the material strength is relatively low, and the surface and internal control surfaces are smooth. Most of the small-diameter, thin-walled seamless pipes are like this.