The Q345B seamless steel pipe refers to the steel seamless pipe using Q345 material. The letter Q here represents the yield type of the material, and the following number represents the yield value of this type of yield. As the material increases in thickness, the yield value of the material decreases slowly. For the last letter, it represents the type of impact temperature. The Q345 series is divided into five grades: A, B, C, D, and E. Grade A represents no impact treatment, and grade B represents a temperature of 20 degrees. Shock treatment is carried out at normal temperature, C grade means impact treatment at 0 degrees, D grade means impact treatment at minus 20 degrees, E grade means impact treatment at minus 40 degrees . Q345B only represents a material standard used by steel seamless pipes, and to truly become a seamless steel pipes requires certain process steps. Similarly, when the seamless steel tube is produced with different processes, the environment used is also differ…