In the medical device industry, the tolerance control of precision medical molds directly impacts product safety and regulatory compliance. Achieving a tolerance of ±0.005 mm has become a core requirement for high-end medical plastic injection molds.
Material selection forms the foundation. We use imported S136 mirror-finish steel or 420 stainless steel, subjected to vacuum heat treatment and cryogenic (deep cooling) processing. This ensures mold hardness of HRC 50–52 with exceptionally high thermal stability, effectively preventing deformation during machining.
Next, equipment and processes are critical. We employ five-axis high-speed CNC machining centers (positioning accuracy of 0.001 mm) and slow wire-cut EDM (cutting accuracy of ±0.002 mm), combined with graphite electrode electrical discharge machining (EDM), to achieve high-precision forming of complex cavities and runners. The entire machining process takes place in a constant-temperature (20 ± 0.5°C) and constant-humidity cleanroom, effectively eliminating the effects of thermal expansion and vibration.
Inspection is equally indispensable. We utilize German ZEISS coordinate measuring machines (CMM) and optical profile projectors for 100% full inspection, with real-time data feedback at every process step. This ensures the final precision medical mold tolerance remains stably controlled within ±0.005 mm. Additionally, nano-level surface polishing and medical-grade PVD coating treatments achieve a surface roughness of Ra ≤ 0.025 μm, fully complying with ISO 13485 and FDA sterile requirements.
Through this systematic process, our medical mold processing team has delivered thousands of high-precision molds to numerous well-known medical device companies, achieving a first-pass yield of 99.8%. Whether for insulin pen molds, ventilator component molds, or implantable device molds, we can consistently realize ±0.005 mm tolerances with ease.