The Influence of Forging Equipment on Mold Life And Forging Economy

Core tip: Commonly used forging equipment such as anvil hammers, impact hammers, mechanical presses, screw presses (including friction presses), and hydraulic presses, due to the loading speed (load) during the forging process

The commonly used forging equipment such as anvil hammers, impact hammers, mechanical presses, screw presses (including friction presses), and hydraulic presses, due to the different loading speeds (load properties) during the forging process, the contact time between the hot blank and the mold during the loading process, and the number of loading times to complete a forging, also affect the mold life and forging economy to a considerable extent. For example, can the loading speed of anvil hammer and counter hammer reach up to 3m/s? 9m/s, screw press (including friction press) is 0 6m/s~1.2m/s, while the loading speed of mechanical press and hydraulic press is the lowest, at 0 06m/s? 0. lm/s and W LM/SO shows that there is a difference of up to 1 in the loading speed of these commonly used forging equipment? Two orders of magnitude. If the degree of deformation during each loading is the same, the surface of the forging hammer and screw press mold cavity will be more severely eroded by the high-speed erosion of hot metal than that of the hydraulic press and mechanical press mold cavity. Moreover, the forging hammer and screw press have severe deformation, temperature rise, and require multiple loading to complete a process, which further exacerbates mold wear.

It seems that a high loading speed will greatly reduce the lifespan of the mold. However, things often have two sides, and different loading speeds will result in differences in the contact time between the hot blank and the mold during the loading process. The difference in "contact time" will lead to differences in the surface temperature of the mold cavity. As is well known, an increase in the surface temperature of the mold cavity will cause a decrease in the hardness of the mold cavity surface, and even cause a phase transition of the surface layer metal, greatly reducing its wear resistance.

There is data indicating that the "contact time" of the forging hammer during the loading process is the shortest, which is 10 times longer than that of the forging hammer for the screw press? 20 times, and the "contact time" of mechanical presses is 3 times that of screw presses? 4 times; Given that hydraulic presses mainly produce large forgings with long working (loading) times, their "contact time" is even longer.

These are only qualitative effects of forging equipment on mold life. Actual production data shows that the mold life of general forging hammers is lower than that of screw presses and mechanical presses.

In addition, the cost of forging equipment (depreciation rate), energy consumption, maintenance and environmental pollution control operating expenses, as well as productivity, also affect the cost of forging. It can be seen that forging equipment also has a significant impact on the service life of forging dies and the economy of forgings, and it is very complex. Moreover, different equipment is suitable for producing different types of forgings. Therefore, when selecting or purchasing new forging equipment, it is necessary to carefully analyze the specific product structure.