The development of precision mold processing relies on the adoption of advanced machining techniques and equipment. The primary machining processes involved in precision mold manufacturing include CNC milling, wire EDM (Electrical Discharge Machining), electrical discharge machining (EDM), grinding, lathe work, and measurement, among others.
From traditional milling machines to three-axis machining centers and high-speed five-axis milling, CNC milling can produce highly intricate three-dimensional complex surfaces with increasingly limited material hardness constraints.
Wire EDM is mainly used for the two-dimensional and three-dimensional linear part machining of various stamping molds, plastic molds, and powder metallurgy molds. In the manufacturing of injection molds, common applications include core holes, ejector pin holes, angled ejector holes, cavity clearance angles, and sliders.
EDM is suitable for machining complex components with precision small cavities, narrow slots, concavities, and angles. When it's challenging to machine complex surfaces with conventional tools, especially when deep cutting with a high diameter-to-length ratio is needed, EDM is superior to milling. The use of milled electrodes for EDM improves success rates and is more cost-effective than expensive tooling for EDM.
Grinding is a precision surface machining process, particularly useful for processing hardened parts. Surface grinders, universal internal/external cylindrical grinders, and coordinate grinders (such as PG optical curve grinders) are the primary grinding machines used in mold manufacturing.
Small surface grinders are mainly used for processing small mold components, such as precision inserts, precision core pins, and sliders. Large surface grinders are commonly used for processing large-sized templates. The trend in surface grinding is to increase the linear speed of the grinding wheel and the high-speed movement of the worktable. With the adoption of advanced components like linear guides, linear motors, and hydrostatic lead screws, motion speeds have improved significantly, and wheel dressing technology continues to advance.
CNC lathes are also commonly used in injection mold workshops. Complex-shaped rotating parts can be easily produced through programming, and the machine tool can automatically change tools, greatly enhancing mold production efficiency. The machining precision of CNC lathes is continually improving with advancements in manufacturing information technology.
High-precision measurement equipment plays a crucial role in the early stages of precision plastic mold design, ranging from digital drafting to mold process measurement, mold acceptance measurement, and mold repair measurement.