Square tube and round tube Climbing frame punching machine Safe operation measures:
Preheat method
Improve plasticity from improving the internal performance of tools and dies
1. The molds and tools that have been used for a period of time shall be preheated regularly, and the preheating temperature shall be controlled below the metal transformation temperature, which has little impact on strength, but can eliminate stress concentration and improve plasticity. Generally, the temperature shall be controlled at 300 ℃~400 ℃, and then surface inspection shall be carried out by naked eye or flaw detection method to eliminate relevant defects.
2. In cold season (the room temperature is lower than 10 ℃), preheat the molds, tools, hammerheads and sliders with a temperature of 200 ℃~300 ℃ every day before starting work to reduce the deformation resistance and enhance their plasticity.
3. For the cooling of molds and tools for hot processing, the temperature of cooling water shall not be too low, and rapid cooling shall not be adopted. Generally, the temperature of cooling water shall be ensured to be greater than 50 ℃.
Zinc steel guardrail punching machine Preventive measures
Square and round pipe punching machine According to the above reason analysis, it can be seen that the internal cause of object strike is caused by flying or popping of fragments after the overall or partial damage of molds and tools, and the focus of prevention is also here. The die and tool materials used for pressure processing are mostly alloy steel, carbon tool steel and hard alloy. They all have a common feature: high strength and hardness, relatively low plasticity and toughness, which is quite beneficial to metal deformation but unfavorable to operator safety. How can we give consideration to both? Based on years of experience, the author believes that starting from improving the process method and looking for preventive measures, the effect is good, the method is simple and easy to operate, and costs are saved.
Square tube Pipe punching machine The main consideration of process improvement is to reduce stress concentration and improve the plasticity of molds and tools. In general, the more serious the stress concentration is, the easier it is to cause local damage of the mold; The worse the plasticity of the module, the easier it is to cause mold cracks. The following methods can be selected to reduce stress concentration and improve plasticity:
Structural optimization method
Reduce stress concentration from optimizing tool geometry, Pipe punching machine In addition to avoiding sharp corners and sharp corners on the appearance and edges of molds and tools, attention should also be paid to:
1. Pay attention to "three minds and one mind". The stress center of the workpiece, the geometric center of the mold and the pressure center of the press are "three in one", which can avoid the damage of the mold due to the stress concentration caused by eccentricity.
2. The side of the upper mold facing the operator should be made into a bevel as far as possible, which can not only increase the operating space, but also reduce the probability of the mold edges and corners being deformed and damaged under the effect of stress due to frequent use, thus popping out.
3. The punch hardness shall be slightly less than the female die HRC5 (hardness value) during the blanking process; When punching small holes with diameter less than 2mm, the guide sleeve of the punch should be as long as possible; During continuous blanking, the hole shall be free from unilateral or asymmetric, in order to reduce the risk of punch damage and ejection.
4. The discharge plate of the mold and the upper and lower molds should be closed as far as possible, especially the side close to the operator.
5. The extrusion processing energy is very large, and the entrance angle a of the extrusion die has a great influence on the unit extrusion force. When α= When the angle is 40 °~60 °, the deformation resistance is small, which is very helpful to improve the safety performance.
