Lost Foam casting borrow cavity for runner study

1. The casting system for the Lost Foam process is of solid foam type. During pouring, liquid metal will pass through quickly in the first place, which will be liquefied into colloidal shape in case of high temperature foam.Foam model gasification takes heat  the liquid metal.The casting temperature of epc is higher than that of traditional casting.The passive increased foam density in the mold cavity increases the demand for heat, so in the case of complex casting system, it often appears that the casting temperature is already very high, but the liquid metal temperature is still low on the casting defects, such as wrinkles, slag inclusion, etc.The temperature in the liquid metal into the mold cavity is effective temperature, pouring temperature cannot represent the temperature of the liquid metal in the mold temperature  carry heat is limited, if you want to make the limited heat as much as possible into the cavity become effective heat, we must strictly control the liquid metal  come to every small steps in the process of entering the cavity of the heat loss.

2. The loss caused by low iron liquid collection rate is the same as the loss of waste products. The finished products are turned into return charge.In particular, the artificial complex gating system  only reduces the yield of molten iron, but also reduces the production efficiency of operators.Due to the unnecessary loss of heat in the complex casting system, the foam model is difficult to fully gasify, which  only fails to achieve a high yield, but also backfires  results in waste products.On the contrary, the simple pouring system is  only easy to operate, but also high yield.By using the mold cavity as the runner, the casting system can be greatly simplified.At the same time, improve the yield of iron liquid  labor efficiency of employees, so as to reduce production costs, so that enterprises have a greater profit space, in the fierce market competition with ease.

3. It is thought that the foam model will shrink into a gelatine in a very short time after the liquid metal enters the mold cavity  is adsorbed on the mold wall by negative pressure to become a cavity. It is worried that the box will collapse once the casting system is too open.The foam model is formed by the fusion of white hollow spherical beads.Because the foam material is white hollow, it is only sensitive to contact   to convection  radiation in the three ways that it receives heat transfer  liquid metal.Foam absorbs heat  shrinks into a gelatinous form when it comes into close contact with liquid metal, giving way.Only the foam that is close to the metal flow will give way,  the cavity will  instantly become a cavity, so that the box will  collapse.

4. The advantages of Lost Foam casting without mold taking  using dry sand filling make it  subject to the restriction of the operation procedures such as split surface, lower core  closing box, etc., as long as it is beneficial to the maximum number of combined model beam  sand filling operation, reasonable distribution of heat field  full gasification of foam model.The basic principle of epc should be followed: the distribution of heat field should be reasonable by adjusting the flow field.The main purpose of the simplified epc system is to reduce heat loss  form a reasonable heat field.In the process of deepening the understanding of casting steel carbon emission method, we realized that the open casting of steel casting, although the liquid steel injection  the riser,  the form of no gating system, but the cavity objectively made the gating system, we borrowed the cavity as the runner.The cavity can be used as a runner.Principle of borrowing: relatively unobstructed cavity;A point  point of relative centrality;A relatively high position;It is better to cut a little to control the filling speed,  do  cut more unless the casting is very large. The multi-cut is the rain pouring method, suitable for thin wall body.The following measures can be taken to prevent the overburning of the flowing area  the initial reverse injection of pouring.The metal liquid is thickened through the zone coating;Adopt vase type reverse spatter direct runner;Control casting speed.