Delrin® 150 Rod

Delrin® 150 is an acetal homopolymer (POM-H), a high-viscosity extrusion grade supplied as rod, plate and calendered sheet. Higher crystallinity than copolymer acetal gives it more strength, hardness and stiffness: tensile strength about 11,000 psi at yield, flexural strength near 14,000 psi, tensile modulus around 350,000 psi and Rockwell M94 hardness. It holds a dynamic coefficient of friction near 0.2 running dry against steel, resists fatigue well enough for snap fits and spring elements, and absorbs little water, about 0.25% in 24 hours and 0.90% at saturation, so machined parts hold their size.

It is the standard stock for precision machined mechanical parts under load: gears, cams, bearings, rollers, bushings, valve components, pump parts, fasteners and conveyor wear components in packaging, food processing, automation, automotive and consumer hardware. Long-term service temperature is about 185°F with intermittent excursions to 300°F, and the melting point is 347°F. It machines and polishes exceptionally well but is difficult to bond, so use mechanical fasteners. Homopolymer acetal is more prone to centreline porosity in large-diameter rod than copolymer, it is less tolerant of continuous hot water above roughly 140°F and of strong alkalis, and Delrin® resin is not sold for implant or long-term internal medical use.