Here are the spiral steel pipe heat treatment processes. You can choose one that suits the steel pipe manufacturing in your project.
1. Thermomechanical treatment. High-temperature thermomechanical treatment can increase the yield ratio and elastic limit of spiral steel pipes. Improve the comprehensive mechanical properties, fatigue properties, and stress relaxation properties of spiral steel pipes. Reducing the ductile-brittle transition temperature and temper brittleness of steel has the advantages of simple process and energy saving. The high-temperature thermomechanical treatment has a significant influence on the spiral tube. The specific process is heating temperature 920-950℃, hot rolling deformation 10%-30%, air cooling time 10-30 seconds, oil quenching; then ordinary tempering or rapid tempering at a high temperature above 400℃.
2. Chemical heat treatment in ferrite state. Chemical heat treatment in the ferrite state, such as nitriding, nitrocarburizing, etc., can significantly improve the surface hardness, wear resistance, corrosion resistance, residual compressive stress, and fatigue life of the spiral tube. The chemical heat treatment temperature is generally between 450 and 600°C. The quenched and tempered spiral tube can be combined with chemical heat treatment and tempering. The chemical heat treatment temperature of the precipitation hardening spiral tube is the same as the precipitation hardening temperature. As the application of spiral steel pipes becomes more and more extensive, the requirements for technology and product diversity of spiral steel pipes are getting higher and higher.
After reading these ways, I think you find the best way for the spiral steel pipe machining.