Our produced piping is the coal mine polyethylene pipe (KM), hereinafter referred to as the piping, which is used for underground water supply and drainage, slurry application, positive pressure ventilation, negative pressure ventilation, and gas drainage. The reference working temperature for the piping is 20°C, with operating temperatures ranging from -10°C to +40°C. There is a pressure reduction coefficient between 20°C and 40°C, and the working pressure is the nominal pressure multiplied by the pressure reduction coefficient. The piping for gas drainage purposes must have a nominal pressure of no less than 1.0MPa.