Spiral steel pipe is a kind of product formed by welding technology, so in the production process for the welding process is very strict. (1) Raw materials are strip coil, welding wire and flux. Strict physical and chemical tests must be carried out before being put into operation. (2) The joint

Seamless steel pipe is perforated with round steel, the surface of the steel pipe without weld is called seamless steel pipe. According to the production method, seamless steel pipe can be divided into hot rolled seamless steel pipe, cold rolled seamless steel pipe, cold drawn seamless steel pipe,

In the process of photocatalytic reaction of large-diameter spiral steel tube, the specific surface area, surface morphology and crystal plane structure of the material have a very important influence on the efficiency of photocatalytic reaction, because the photocatalytic reaction mainly occurs on