How to use resin sand for casting?
Resin sand is a type (core) sand that only uses resin as a binder. Regeneration of old sand is to remove the binder film on the surface of the sand to the maximum extent. Adjust the surface (particle size) of the sand to make it very economical. Use new sand. Recycling of old sand can save new sand consumption and transportation costs for discarding old sand.
Moreover, the regenerated sand has uniform grains, smooth surface and good thermal stability, which is beneficial to improve the quality of castings, especially the regeneration of resin sand. When used, the amount of resin added can be reduced, the cost of resin sand can be reduced, and environmental pollution caused by discharged waste sand can also be reduced
1. Method of resin sand casting
Mass production factories should create conditions to adopt technologically advanced modeling and core-making methods. The old-fashioned shock-type or shock-type molding machine production line is not high in productivity, the labor intensity of the workers is large, the noise is large, and it is not suitable for the requirements of mass production, so it should be gradually reformed. For small castings, a boxless high-pressure molding machine production line with horizontal or vertical parting can be used. The production efficiency of solid molding is high and the floor space is small; for middle parts, various box-type high-pressure molding machine production lines and gas can be used. Molding line to meet the requirements of fast, high-precision molding production line, core-making methods can be selected: cold core box, hot core box, shell core and other high-efficiency core-making methods. Medium-volume large castings can consider the application of resin self-setting sand molding and core making.
Single-piece and small-batch production of heavy castings, manual modeling is still an important method, manual modeling can adapt to various complex requirements more flexible, does not require a lot of process equipment. Water glass sand molds, VRH water glass sand molds, organic ester water glass self-hardening sand molds, clay dry molds, resin self-hardening sand molds and cement sand molds can be used; for single-piece heavy castings, the pit molding method is used for low cost and put into production fast. It is more suitable for mass-produced or long-term shaped products to adopt multi-box modeling and split-box modeling. Although the initial investment in molds and sand boxes is high, it can be compensated by saving modeling man-hours and improving product quality.
2. Brief introduction of resin sand:
Resin sand Crystrip plastic pellets are pellets made of thermoplastic acrylic or polymerized thermosetting amines.
The angular pellet design provides an effective treatment method for most dry strip surface coatings. Crystrip plastic is chemically inert. Through proper use and recycling, this dry strip method can reduce the generation of hazardous waste and reduce environmental pollution.