2024

Details of precision machining, forging and casting

In the process of using precision machining, its mechanical properties are better than cast iron, but the cast iron performance of this material is poor, the melting point is higher than other materials. Its processing in the process of the need to pay attention to the problem is quite a lot, mainly because the liquidity of the steel is relatively poor, in the process of processing, we prevent precision machining to produce insufficient pouring or cold segregation, precision machining of the wall thickness can not be less than 8mm. The structure of the casting system is relatively simple, in the process of using its equipment in the cross-section size if the cast iron is large, so that in the process of processing can also be used in its hot casting or dry casting.

Temperature to determine the melt in the process of transferring a good mobility, choose the precision machining temperature should be based on the transfer distance, the transfer of the process of cooling, alloy, specifications, flow and other factors to determine the precision machining temperature than the alloy liquid-phase line temperature is higher than the temperature of the liquid-phase line of 50 to 110 ℃. Production temperature can determine its melt in the process of reinjection will have good mobility, equipment in the process of selecting its casting temperature needs to be based on its reinjection distance as well as the reinjection process cooling situation and some other factors to determine.

The details of precision machining are as follows:

1, in order to prevent stainless steel castings in the casting process, white mouth phenomenon, to take measures in the casting process, otherwise can not make the wall thickness too thin. Aluminum alloy, magnesium alloy metal mold castings, casting rounded corners not less than 2-5m.

2, stainless steel castings pouring slope should be slightly larger than the slope of sand castings. Generally, it should be 38-40% larger than the sand type.

3, stainless steel castings to small wall thickness should be greater than sand castings, because the metal mold heat dissipation fast.

4, stainless steel castings of the inner wall and the inner rib thickness is generally connected to the outer wall thickness of 0.55-0.65. In addition, due to the slow cooling of the inner wall (rib), the casting shrinkage is easy to produce cracks at the junction of the inner wall and outer wall.