Precision casting is a commonly used forging technology in the forging industry, which also includes many small processes. Wax casting is a key link in precision casting, and its quality directly affects the quality of precision castings. Next, Fengzhuo Hardware will share with you some common drawbacks and solutions of wax casting.

1. Wax mold deformation: After the wax mold is removed from the mold, in addition to a decrease in size, sometimes the wax mold is artificially deformed due to improper handling during removal; Due to the common deviation of wax molds during the cooling process, wax molds that have just been removed from the mold should be carefully placed, usually using a larger plane as a reference plane. In addition, it may also be caused by factors such as excessively soft casting accuracy and unreasonable mold design.

2. The surface depression of wax molds is mainly due to insufficient injection pressure and time, high wax temperature, insufficient cooling time, and sometimes too much releasing agent. The surface depression involves a large area, which is difficult to repair and can easily cause waste.

The main reason for insufficient filling of wax molds is that the temperature of the wax material is too low, the injection speed is slow, and the temperature and pressure are low, resulting in rapid cooling during the wax material flow process. This indicates that the wax molds in the corners, edges, or thin-walled parts are not satisfactory, and round corners appear in the corners, which is very similar to a shortage of casting accuracy.

4. The wrinkling on the surface of wax molds is caused by low wax temperature, low firing rate, and improper coordination between wax movement and pressure temperature; Or the inner surface of the pressure type is damaged or not clean; Improper placement of cold metal blocks leaves movement marks on the surface of the wax mold. Deep grain size, similar to cold insulation defects in precision castings; Another issue is that around the mold core and holes, there may be slight indentations at the seams, which is actually due to the poor fusion of the two wax flows at the junction. This is the result of insufficient temperature and pressure of the wax material.

5. Wax molds have seams, which is one of the most common drawbacks, that is, there are very thin wax pieces escaping from the joints of compression joints, compression blocks, and core to core joints. The main reason is that the injection molding accuracy is not high, some of the inner surfaces or joint surfaces of the injection molded parts are damaged, or the injection molding force is insufficient, resulting in high injection molding pressure. Or the wax is too hot. Before the wings can be completely removed, wax molds can be used.

6. There are foam in the wax model. One is the foam on the surface visible to the naked eye, and the other is the foam in the wax model. This is usually too large to be seen by the naked eye, but you can find the local expanding wax model, which is caused by the expansion of gas in the wax model.

7. The wax mold sticking to the compression mold is caused by the lack of release agent, high temperature of the wax mold and compression mold, and insufficient cleanliness of the inner surface of the compression mold.

8. The rough surface of the wax mold is due to low injection pressure, or insufficient density of low wax mold injection rate and inner surface pressure, which can result in serious wrinkles.

What are the material choices for stainless steel precision casting of cold iron

Precision casting manufacturers refer to the cooling material placed inside the mold cavity and on the working surface as cold iron in order to improve the local cooling rate of stainless steel precision castings during forging. In the forging production of stainless steel castings, a cold iron pouring system and a riser are often used to jointly control the solidification process of the castings, in order to obtain qualified castings.

The selection of stainless steel precision casting materials for chillers allows for the selection of multiple materials, including metal and non-metal materials with higher thermal conductivity and greater heat storage coefficient than sand materials. Common materials for chillers in production include cast iron, aluminum alloy, graphite, and copper alloy. The heat storage coefficient of cast iron chillers is relatively high. It can absorb more heat and has strong cooling ability. Stainless steel precision cast iron chiller is easy to manufacture and has low cost. Widely used in precision casting of aluminum and magnesium alloys.

When choosing stainless steel precision casting cold hard materials, we should all choose them in the correct way. Choosing a suitable and satisfactory casting method is what we need.