Delrin® 500AF Full Strength Rod

Delrin® 500AF Full Strength is acetal homopolymer at the full 20% PTFE fibre loading on the medium-viscosity Delrin® 500 base resin - half again the PTFE of the 500AF Blend, which is diluted back to 13%. The 500 base has the more crystalline structure of the two and improved machining characteristics; the 100 base is the tougher one where the part takes shock. Published properties for the 20% PTFE stock shape - one datasheet covers the loading rather than each base resin - are 6,630 psi tensile strength at yield, a 540,000 psi tensile modulus, 12,500 psi flexural strength, 12,600 psi compressive strength and 30% elongation at break, with heat deflection at 244°F under 264 psi and 334°F under 66 psi, and friction against steel runs dry at 0.18-0.19 static and 0.19-0.20 dynamic.

It is machined into sleeve and thrust bearings, bushings, cams, gears, slide plates, guides, rollers and valve seats for business machines, printing, packaging and conveyor equipment and automotive assemblies, running dry against steel or against other plastics. The PTFE is present as fibre rather than powder, and stock shapes machine well and produce the good surface finish that bearing bores need. Limitations, stated plainly: against the 13% blend the full loading gives up tensile and compressive strength and hardness, so buy it for PV capability and low friction rather than as a general upgrade; it is not resistant to hot water above 140°F; strong acids attack the acetal matrix; brown is the colour supplied; and the grade is not FDA, NSF or USDA compliant. Melting point is 350°F, continuous service 185°F and flammability UL 94 HB.