Measures to reduce the thickness of pipes include:
1) Reduce the value of tensile stress at the position where tensile deformation occurs outside the neutral layer. For example, the method of resistance local heating is adopted to reduce the deformation resistance of the metal material inside the neutral layer, so that the deformation is more concentrated in the pressure part, and the purpose of reducing the stress level of the tension part is achieved.
2) Change the stress state in the deformation zone and increase the component of compressive stress. For example, changing the bend to push bend can fundamentally overcome the defect of the tube wall becoming thinner.
The bending moment of actual pipe bending not only depends on the performance of the pipe, the shape and size of the section, the bending radius and other parameters, but also has a great relationship with the bending method and the die structure used. Therefore, at present, it is impossible to express many factors with calculation formulas, and only estimates can be made in production.!
What should be done to reduce the pipe thickness of the pipe bending machine? First of all, it should be clear that the different performance of the pipe bender has different requirements for the wall thickness reduction rate. For example, the pipe fittings used in industrial pipeline engineering shall not exceed 10% for high-pressure pipes; For medium and low pressure pipes, the thickness shall not exceed 15% and shall not be less than the design calculated wall thickness.