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How can Manhart (Guangdong) CNC Machine Tool Co., Ltd. avoid material cracking during the rolling process?

To avoid material cracking during the rolling process, the following measures can be taken:
1. Control deformation rate: When rolling, the deformation rate of the material should be controlled to avoid excessive deformation leading to stress concentration and cracking. Rolling can be carried out through multiple steps, gradually increasing the deformation to reduce cold work hardening and internal stress.
2. Keep the surface clean: Keep the surface of the rolled sheet material clean, avoiding impurities such as oil stains and rust, to prevent stress concentration from causing cracking. Before rolling, the material should be cleaned and rust removed.
3. Pay attention to the rolling direction: When cutting, pay attention to the rolling direction of the plate, and try to make the fiber direction as straight as possible with the bending coil line. This can reduce the stress concentration of the material during the rolling process and reduce the risk of cracking.
4. Eliminating stress concentration factors: During the rolling process, factors that may cause stress concentration should be eliminated, such as the quality of the circular seam end face of the sheet metal, the welding seam splicing interface, etc. Stress concentration can be reduced by smoothing and removing burrs.
5. Preheating and warm rolling: For certain temperature sensitive steels, such as quenched steel, annealing treatment or removal of heat affected zone can be carried out before rolling. In addition, the ambient temperature during the rolling process should be higher than the brittle transition temperature of the steel. If the ambient temperature is too low, the plate should be preheated and rolled to reduce the risk of stress concentration and cracking during the rolling process.
6. Reasonable selection of materials: Select suitable materials according to the requirements of the product and the usage environment, and try to avoid using steel that is prone to cracking. For certain low alloy and alloy steels, normalizing treatment can be considered to improve their toughness and reduce the risk of cracking.
In summary, the key to avoiding material cracking lies in controlling deformation rate, maintaining surface cleanliness, paying attention to rolling direction, eliminating stress concentration factors, preheating and heating, and selecting materials reasonably. During the rolling process, it is important to closely monitor the deformation and surface quality of the material, promptly identify any issues, and take appropriate measures to adjust to ensure the safety and stability of the rolling process.