Why Are Injection Molds So Expensive?
As the core equipment for plastic product production, the cost of injection molds typically accounts for 30%-50% of the entire production project. This high cost is primarily attributed to the multi-dimensional technical requirements and complex manufacturing processes involved in mold development.
1. High-Precision Design Costs
Mold structures require specialized CAE software for mold flow analysis, stress simulation, and tolerance calculations. The design cycle for complex product molds can take 2-3 months. The balanced runner system design for multi-cavity molds requires experienced engineers to repeatedly optimize.
2. Special Material Consumption
Mold cores commonly use imported pre-hardened steel (such as P20, 718H) or quenched tool steel (such as H13), with hardness requirements of HRC48-52. The cost of steel for a single set of molds can reach tens of thousands of yuan. The cost is even higher when using hard alloys for wear-resistant inserts.
3. Precision Machining Investment
High-end equipment such as five-axis machining centers (accuracy ±0.005mm), slow wire cutting (accuracy ±0.002mm), and mirror EDM are required. Machining labor accounts for over 40% of the total cost. The electrode wear rate for deep-cavity molds can reach 30%.
4. Surface Treatment Processes
Nitriding treatment (surface hardness HV1000) costs about 300-500 yuan/kg, and DLC coating costs about 0.8 yuan per square centimeter. Complex molds require special tooling for heat treatment and deformation control.
5. Mold Testing and Validation Costs
New molds typically require 3-5 iterations of testing, with each test consuming raw materials, machine time, and labor costs. The debugging cycle for automotive parts molds can take up to 2 months.
