Dimensional stability.
Low friction.
Food-contact capable.

PET Ertalyte: FDA compliant for food contact, higher tensile strength (90 vs 70 MPa), better dimensional stability in humid conditions. Delrin (POM): better impact strength, slightly lower friction, more familiar to most engineers. For food/pharma, use PET. For general mechanical without regulatory requirements, Delrin is usually cheaper and adequate. PET is about 20–30% more expensive than Delrin.

Same chemical family (polyesters) with different backbone chain lengths. PET: better dimensional stability, higher tensile strength, FDA food-contact compliant. PBT: faster crystallization (better for injection molding), higher HDT (210 °C vs 110 °C for PET), superior electrical properties. PET for precision mechanical and food-contact; PBT for electrical and automotive.

Yes — one of its best applications. Ertalyte (unfilled) runs dry against 316L stainless or hardened steel shafts at PV values up to 3,000 (psi·fpm). Ertalyte TX (internal lubricant) doubles that rating. For higher loads, consider Vespel or PEEK-bearing grades. Never run PET dry against aluminum (galling).

Yes. PBT welds well via ultrasonic, vibration, hot-plate, and laser transmission welding. Weld strengths typically 70–90% of parent material. Ultrasonic is the most common production method for PBT connector assembly. PET also welds but less commonly used in welded assemblies.

Yes — for moderate structural loads. Tensile 140 MPa, flexural modulus 10 GPa. Common for automotive brackets, tool housings, appliance structural components. For high-load structural, consider PA66-GF30 or PEEK-GF30. PBT-GF30 sweet spot: medium-load structural parts requiring electrical insulation or chemical resistance that nylon can't match.