Method for determining casting surface of precision casting

The position of the casting in the metal mold casting during casting jeopardizes the quality of precision castings, the precision of specifications, and the degree of difficulty in modeling and processing.

Selection criteria for pouring parts:

1. The key production and processing surface of the precision casting or the key production and processing face is facing down or located on the side: when pouring, the vapor in the metal material liquid, the slag and the sand in the metal mold will be adjusted, and some will make the casting The upper end of the part has defects such as air holes, welding knobs, sand holes, etc., and the probability of defects at the bottom of the casting is higher in the mechanism.

a. For the pouring part of the CNC lathe body, the slide rail should face down to ensure the quality of the key tunneling working face. The quality requirements on the circle are relatively high. The vertical pouring plan is adopted to keep the circle on the side, and the quality and quantity are uniform.

2. The large plan of the precision casting is poured downward or skewed: Because the hot metal material liquid has obvious radiant heat on the upper end of the metal mold during pouring, the sand mold on the wall rises and even cracks, which makes the large plan appear. Sand, sand holes and other disadvantages. The large floor plan can be used to prevent the manufacturing welding defects of the large floor plan from being cast down or by using skewed pouring.

3. The thick walls of precision castings are facing downwards, tilted or skewed: In order to avoid the shortcomings caused by the thick walls of the castings and the failure to cast them, the thick walls with a large total area should be placed under the castings, or On the outer wall or in a skewed area.

4. The vast majority of the thickness of precision castings should be placed on the top or on the side of the clinical diagnosis surface. The key purpose is to facilitate the placement of feeders in the thick places to carry out the shrinkage.