Wholesale POM C Tube Manufacturer & Precision Hollow Bar Products

POM-H (homopolymer, such as Delrin) features a higher crystalline melting point and slight mechanical stiffness advantages, but it suffers from severe centerline porosity when extruded into heavy cross-sections and exhibits low chemical resistance to alkaline hydrolysis. POM-C (copolymer) contains comonomers that prevent erratic shrinkage voids, providing uniform density throughout the cross-section. POM-C also resists continuous hot water, chemical cleaners (pH 4-13), and thermal aging.

Drilling large-diameter bores into solid rods relieves residual cooling stresses unevenly across the profile, often resulting in axial banana-bowing or egg-shaped bore ovality. Our extruded hollow POM C tubes undergo dual-axis vacuum calibrator stabilization followed by an extended 24-hour thermal annealing cycle. The residual stress state is balanced symmetrically around the annular axis, ensuring the tube remains round and straight after multi-axis CNC lathe operations.

SHUNDA manufactures POM C tubes ranging from an Outer Diameter (OD) of 20 mm up to 400 mm, with Inner Diameters (ID) engineered from 10 mm up to 340 mm. Standard commercial lengths are 1000 mm, 2000 mm, and 3000 mm. We also provide customized OD/ID configurations, tight metric or imperial tolerance tooling, and pre-cut lengths upon contract review.

Yes. Our virgin natural white POM C tubes comply with FDA 21 CFR 177.2470 and European Regulation (EU) No 10/2011 for direct food contact. For jet black POM C tubes, specialized non-heavy-metal, food-approved carbon black masterbatches are utilized upon request to maintain FDA conformity for sanitary food sorting and beverage packaging equipment.

Use sharp, polished carbide or polycrystalline diamond (PCD) tooling with positive rake angles (15° to 30°) and clearance angles of 6° to 10°. Surface cutting speeds typically range between 250 and 450 m/min, with feeds of 0.1 to 0.3 mm/rev for roughing and 0.05 mm/rev for finishing. Because plastics conduct heat poorly, air-blast or water-soluble flood coolants are recommended to clear swarf and prevent localized thermal expansion during continuous turning.

We deploy continuous ultrasonic non-destructive testing (NDT) within our extrusion calibration lines to detect internal micro-voids and monitor wall concentricity. Post-extrusion, sample cross-sections are subjected to polarized light photoelastic stress evaluations and formal EN 10204 3.1 mechanical tensile and hardness testing, ensuring consistent batch-to-batch quality before export crating.