1. Production Process of Sand Casting
Sand casting molding materials are inexpensive and readily available, and the mold manufacturing process is simple. There are almost no restrictions on the types of casting alloys, casting structures, sizes, or production batches. Sand casting can produce castings with highly complex external shapes and internal cavities, such as various boxes, beds, frames, etc. It can also produce castings ranging from a few grams to hundreds of tons, making it suitable for single-piece, batch, and mass production. The production of sand casting involves multiple steps, including molding and core-making, alloy melting, mold assembly and pouring, casting cleaning, and inspection.
2. Sand Casting Process Design Steps
Sand casting process design should be based on an analysis of the castability of the part structure, combined with production volume, technical requirements, and production conditions. This includes selecting molding and core-making methods as well as mold types, and determining pouring positions and parting surfaces. The specific steps are as follows:
1) Review the part drawings and analyze the technical requirements, structural characteristics, and castability of the part.
2) Develop the process plan, select molding and core-making methods, determine the mold type, pouring position, parting surface, and measures to prevent deformation and cracking. Select process parameters such as machining allowances, draft angles, casting shrinkage, and non-cast holes and grooves. Determine the number and arrangement of castings in the sand mold.
3) Design the sand cores, determine the type, quantity, core head structure, and core placement sequence.
4) Design the gating system, risers, chills, feeders, and vent holes.
5) Draw the casting process diagram and related drawings (such as casting drawings and mold assembly drawings).
6) Design process equipment, including template drawings, core box drawings, special measuring tools, and combined core placement fixture drawings.
7) Prepare operational process specifications and technical documents such as casting process cards.
