Casting process equipment is the general name of the mold and device used in the process of molding, core making and box closing.
1. Selection of pattern materials
Pattern is a necessary process equipment in the molding process, which is used to form the mold cavity, so it is directly related to the shape and size accuracy of the casting. The support is mass produced, so the metal pattern is used. The material of the metal pattern is as follows:
Pattern: aluminum alloy (light weight, no rust, good processing performance, smooth surface after processing, with certain wear resistance, but poor wear resistance)
Air outlet pin and air hole pin: 45 steel
2. Determination of metal pattern size
Pattern size = casting size (1 + k), (pattern size accurate to two decimal places)
Note: linear shrinkage of K casting
Shrinkage of bearing k = 1.5%
3. Technical requirements for metal pattern
The dimensional accuracy and surface finish of pattern are important factors affecting the quality of casting, so the surface finish and dimensional deviation should be strictly controlled.
According to table 1.5-5 in practical foundry manual, it can be concluded that:
The surface roughness of the pattern is 3.2, and that of the contact surface between the pattern and the template is 6.3.
4. Production method of metal pattern
In order to increase the density of the material after pouring, the material is now made into a cavity similar to the shape of the pattern, and then heat treatment is carried out to increase its hardness and wear resistance, and then the machine is used to process it into the shape of the pattern according to the size of the pattern.
Design of formwork
Template, also known as shaped plate, is assembled by touching the bottom plate and pattern, pouring and riser system and locating pin, etc. The die base plate is used to connect and support the pattern, pouring system, locating pin, etc. In this design, a single die base plate is used, and its working face is plane.