PET (Ertalyte) Comparisons — vs Acetal, Nylon, PEEK & PETG

Ertalyte (bearing-grade PET-P) is a specialized material — it earns its place in applications where acetal falls short on moisture stability, where nylon swells and seizes, or where the application demands FDA compliance with dimensional precision. This page maps Ertalyte against the most common competing bearing and wear plastics to clarify when each is the right choice.

At a glance:

• Ertalyte vs acetal: Ertalyte wins in wet environments; acetal wins on cost and machinability
• Ertalyte vs nylon: Ertalyte is dramatically superior in wet dimensional stability
• Ertalyte vs UHMW: Ertalyte is harder/stiffer; UHMW handles higher impact at low speed
• Ertalyte vs PEEK: PEEK wins at >212°F; Ertalyte is cost-effective below that
• Ertalyte ≠ PETG: completely different material; PETG is amorphous, clear, and not a bearing plastic

PET (Ertalyte) vs Acetal (Delrin)

The most common direct comparison. Both are FDA-compliant, semi-crystalline, low-wear thermoplastics used for bearings, bushings, and precision machined parts.

Choose Ertalyte when: the part runs in water, process fluids, or wash-down; dilute acids (citric, acetic, phosphoric) are present; or moisture-induced bore growth would cause a nylon or acetal bushing to change clearance unacceptably.

Choose acetal when: the environment is dry; cost is a primary factor; machinability is critical (acetal produces cleaner, shorter chips and machines faster); or compressive strength is the governing load parameter (acetal is marginally higher in compressive strength).

See the dedicated PET vs acetal (Delrin) comparison for a full head-to-head.

PET (Ertalyte) vs Nylon 6/6

This comparison tends to resolve decisively in most applications:

Choose Ertalyte when: the bushing or bearing is exposed to water, food-grade process fluids, or wash-down. A nylon bore that is machined to a precise running fit will close up as the nylon absorbs moisture — Ertalyte maintains its machined dimensions.

Choose nylon when: the application is dry, the design can account for moisture-related dimensional change, or impact toughness is the primary concern (nylon absorbs impact energy better than Ertalyte).

PET (Ertalyte) vs UHMW Polyethylene

UHMW (Ultra-High Molecular Weight Polyethylene) and Ertalyte are both low-friction wear plastics often used for the same application class, but with meaningfully different performance profiles:

Choose Ertalyte for precision machined parts, components requiring tight bore tolerances, or applications where creep/cold-flow under sustained load would cause UHMW to deform unacceptably.

Choose UHMW for wear liners, abrasion pads, and applications with large impact loads at low speed, where the lower modulus acts as a beneficial cushion.

PET (Ertalyte) vs PEEK

Choose PEEK when continuous operating temperature exceeds 212°F, when chemical resistance to aggressive solvents is required, or when the part must survive steam sterilization above 121°C.

Choose Ertalyte when operating conditions are within the 100°C limit and the 4–5× cost premium for PEEK cannot be justified. For most food-zone bearing applications below 200°F, Ertalyte is the cost-effective solution.

PET ≠ PETG — A Critical Distinction

This is the most important comparison on this page: Ertalyte (PET-P) and PETG are not interchangeable materials.

Substituting PETG for Ertalyte in a bearing application is a failure mode. PETG's amorphous structure has far lower hardness, poor creep resistance, and no wear engineering. Substituting Ertalyte for PETG in a display or thermoformed application gives you an opaque, non-formable part. The materials serve completely different purposes.

The full explanation of the structural and performance differences is in the PET vs PETG comparison.

More related guides

Applications

• Bushings & Bearings
• Wear Strips & Slides
• Food Processing Components

Industries

• Food & Beverage

Compare to other materials

• PET vs. PETG
• PET vs. Acetal (Delrin)
• PET vs. Nylon

Frequently asked questions — PET FAQ