Precision POM Medical Test Cover Plate with Dimensional Stability and Defect-Free Surface Control

We manufactured a precision POM (polyoxymethylene) medical test cover plate for a diagnostic equipment application. POM offers high stiffness, low friction, excellent dimensional stability, and good chemical resistance — making it a preferred material for medical test components that require precise fit and repeated usage . However, POM machining presents specific challenges: the material's high crystallinity and low thermal conductivity make it susceptible to localized heating and thermal expansion during cutting, its relatively low softening temperature requires careful heat management, and residual stresses from machining can cause post-process dimensional drift . For this cover plate, we addressed these challenges through: sharp carbide tooling with optimized rake angles to minimize cutting forces and heat generation, controlled cutting parameters — moderate speeds with consistent feed rates to prevent localized melting or smearing, staged rough-to-finish machining with stabilization periods to allow stress relaxation, and flood coolant application to maintain stable part temperature throughout cutting . POM's machinability, combined with these controlled parameters, delivered the precision flatness, smooth surface finish, and dimensional stability required for reliable test equipment operation . The result: a POM cover plate meeting medical device quality standards.

Project Overview

Key Technical Highlights

• Thermal Management in POM Machining: POM's low thermal conductivity means heat concentrates at the cutting zone. Applied sharp carbide tools with positive rake geometry to minimize friction, controlled cutting speeds (200-400 m/min recommended range) to prevent localized heating above POM's softening point, and flood coolant to maintain stable part temperature throughout the cut .
• Stress-Relief and Dimensional Stability: POM can retain residual stresses from material processing and machining. Implemented staged roughing with 0.5-1.0mm finishing allowance, followed by ambient stabilization, then precision finishing — allowing stress relaxation before final dimensioning .
• Surface Quality and Defect Prevention: POM's machinability requires sharp tooling to prevent smearing or melting. Used two-flute solid carbide end mills with optimized feed rates to produce clean, chip-free surfaces without thermal damage .

Quality Verification

CMM inspection verified dimensional accuracy (±0.02mm) and flatness (≤0.02mm) after stabilization period. Surface roughness confirmed at Ra≤1.6μm. Visual inspection verified defect-free surfaces with no tool marks, melting, or smearing.

Industry Applications

Ideal for medical test equipment cover plates, diagnostic device housings, precision instrument covers, and medical components requiring dimensional stability and chemical resistance.

Why Partner With Us?

• Proven expertise in POM Precision machining with thermal and stress management
• Controlled cutting parameters for defect-free surfaces
• Staged processing protocols for dimensional stability
• 12+ years of precision manufacturing experience across medical and diagnostic sectors