During the stress-relief quenching process of the special-shaped steel pipes, the pipes undergo internal plastic deformation under a certain temperature effect.(When the local stress exceeds the yield strength of the material at that temperature.)Or the entire process of partial relaxation time(When the local stress is below the yield strength of the material at that temperature)To relax residual stresses for the purpose of removal. During stress-relieving quenching, the product parts are generally heated slowly to a lower temperature.(Gray Cast Iron500~550The temperature is ℃, and the special-shaped steel pipe is available.500~650℃,Rare metal aluminum alloy metal stamping parts are for work hardening as the temperature gradually drops.).Maintain for a period, then slow down the cooling to avoid creating new internal stresses.
Heat Treatment Furnace Quenching:Heating the non-standard tube to a certain temperature(Generally, under changes in temperature or during processing hardening temperature.)A heat-insulating and insulating process for a period, followed by a slow cooling to relieve the heat stress in various non-standard steel pipes.
In most cases, after the entire production process is completed, a certain amount of internal stress will remain within the metal material. Internal stress can cause cracking, deformation, or dimensional changes in the products of non-standard steel pipes. It also enhances the chemical specificity of the metal material, making it particularly susceptible to stress corrosion cracking under the residual tensile stress. Therefore, internal stress can affect the application performance of non-standard steel pipes or lead to premature failure of the products.
Hardening by quenching in ground stress cannot completely eliminate internal stresses within the shaped steel pipe; it can only remove the majority. To completely resolve internal stresses, the shaped steel pipe must be heated to a higher temperature. Under such standards, other tissue transformations may occur, which can severely impair the application performance of the shaped steel pipe.
