1. Thick-walled steel pipe cutting: According to the actual required pipeline length, the pipe should be cut with a metal saw or a toothless saw. When using water welding during the cutting process, the raw materials should be protected accordingly. When cutting, fire-resistant and heat-resistant materials should be used as baffles at both ends of the fracture to catch the sparks and hot iron beans falling during cutting and protect the original plastic layer of the raw materials.

2. Thick-walled steel pipe pipeline connection: After the plastic filling is completed, the pipe and the pipe fittings are connected and installed. During the connection process, rubber pads are added between the flanges and the bolts are tightened to a sealed state.

3. Thick-walled steel pipe plastic coating treatment: After polishing, oxygen and C2H2 are used to heat the pipe mouth on the outside of the pipe until the internal plastic layer is melted. Then the technical workers will evenly apply the prepared plastic powder to the pipe mouth. It should be noted that the corresponding application should be in place, and the flange plastic coating should be applied above the water stop line. The heating temperature should be strictly controlled during this process. If the temperature is too high, bubbles will be generated during the plastic coating process. If the temperature is too low, the plastic powder will not be completely melted during the plastic coating process. The above situations will cause the plastic layer to fall off after the pipeline is put into use, and the thick-walled steel pipe of the pipeline will be partially corroded and damaged in the later stage.

4. Grinding of the pipe mouth of thick-walled steel pipe: After cutting, the plastic layer of the pipe mouth should be polished with an angle grinder to avoid melting or even burning of the plastic layer during flange welding to damage the pipeline. Use an angle grinder to polish the plastic layer of the pipe mouth.

To improve the corrosion resistance of thick-walled steel pipes and extend the service life of the product, thick-walled steel pipes need to be pickled and passivated to form a protective film on the surface. Thick-walled steel pipes have high hardenability, good machinability, and medium cold deformation plasticity and weldability. In addition, the toughness of the steel does not decrease much during heat treatment, but it has quite high strength and wear resistance, especially when quenched in water. However, this steel is highly sensitive to white spots, has a tendency to temper brittleness and overheating sensitivity during heat treatment, has high strength and hardenability, good toughness, small deformation during quenching, and high creep strength and long-term strength at high temperatures. It is used to manufacture forgings that require higher strength than 35CrMo steel and larger tempered sections, such as large gears for locomotive traction, supercharger transmission gears, rear axles, heavily loaded connecting rods, and spring clips. It can also be used for oil-deep well drill pipe joints and salvage tools below 2000m and can be used for bending machine molds.