The cost of precision casting can be broken down into six core modules, and the proportion of different modules in agricultural machinery components varies significantly:
| Cost module | Core Content | Proportion range (agricultural machinery components) |
Characteristics of agricultural machinery scenes |
| Mold/tooling cost | Investment casting wax mold (steel mold/aluminum mold), EPC foam mold, shell casting mold, etc | 10%-30% | Large batch of agricultural machinery (such as an annual production capacity of 100000 tractor gearbox housings), with low cost sharing of molds; Small batch customized parts (such as special agricultural machinery components) with high cost sharing |
| Material cost | Metal raw materials (alloy steel, ductile iron, high chromium cast iron, etc.), shell materials (quartz sand, binders), etc | 35%-50% | The wear-resistant components of agricultural machinery (plowshare, deep loosening shovel) require expensive materials such as high chromium cast iron, which accounts for a relatively high proportion; Aluminum alloy hydraulic components have relatively low material costs |
| Shell making/molding cost | Wax mold pressing and multi-layer coating of the shell in investment casting; Foam forming and sand box filling of EPC | 15%-25% | Complex structural components, such as hydraulic valve bodies and seeder impellers, require multiple shell making processes and have a high cost proportion; Low proportion of simple components (such as shaft sleeves) |
| Casting/melting cost | Energy consumption and manual labor for metal melting (electric furnace/medium frequency furnace), pouring operation, temperature control, etc | 8%-15% | High melting point alloys (such as alloy steel) have high energy consumption during melting; Continuous pouring can be used to reduce unit costs during mass production |
| Post processing cost | Cleaning (removing sprues and casing residues), heat treatment (quenching/tempering), and minor machining (critical surfaces) | 5%-12% | Agricultural machinery components need to be wear-resistant, and the cost of heat treatment accounts for a high proportion; Precision casting has a small machining allowance, reducing machining costs by 50% compared to traditional casting |
| Testing/Waste Cost | Dimensional testing (three coordinate measurement), mechanical performance testing (tensile/impact testing), waste loss | 3%-8% | High precision components such as seeders and hydraulic valve cores have high testing costs; After the process is mature, the scrap rate can be controlled at 1% -3% (traditional casting 3% -8%) |
Typical case
A tractor gearbox housing (ductile iron QT600-3, annual batch of 100000 pieces), with a precision casting unit cost of approximately 850 yuan/piece, including material cost of 420 yuan (49%), mold sharing of 85 yuan (10%), shell making+casting of 180 yuan (21%), and post-treatment+testing of 165 yuan (19%); If traditional sand casting and machining are used, the unit cost is about 980 yuan/piece (material cost 400 yuan+casting 220 yuan+machining 320 yuan+testing 40 yuan), while precision casting is actually more cost-effective.
