5M AF-Type Timing Belt Pulley 25/30T Synchronous Wheel For 15mm/20mm Width Belt

The tooth count affects your drive ratio and belt speed. A 25-tooth pulley paired with a larger driven pulley gives a higher reduction ratio, useful for torque-heavy applications. A 30-tooth pulley runs more smoothly at moderate speeds and reduces tooth-engagement frequency, which can lower noise and belt wear. Match the tooth count to your calculated drive ratio requirements.

Measure your motor or shaft diameter precisely with calipers. Select the bore that matches your shaft — for example, a NEMA 17 stepper motor typically has a 5 mm shaft, while larger servo motors may use 8 mm, 10 mm, or larger. Keyway-bored variants (shown with dimensions like "8mm(3x1.4mm)") include a keyway slot for a key and set-screw positive drive.

A plain round bore relies on set screws alone to grip the shaft. A keyway bore includes a machined slot that accepts a standard key, providing a positive mechanical connection that resists rotational slip under higher torque loads. The keyway dimensions (e.g., 3×1.4 mm, 4×1.8 mm, 5×2.3 mm, 6×2.8 mm) are listed in the variant name.

Yes — these pulleys are designed for the standard 5M pitch (5 mm tooth pitch) synchronous belt profile. Ensure your belt width matches the variant you select: choose the 15 mm belt-width variant for 15 mm wide belts, and the 20 mm variant for 20 mm wide belts. The flanges are sized accordingly to retain the belt.

The load capacity depends on the material and bore type of the specific variant. For precise load ratings, refer to your belt manufacturer's published 5M drive capacity tables, which factor in pulley tooth count, belt width, and operating speed. Keyway-bored variants handle higher torque than plain-bore set-screw-only configurations.

Corrosion resistance depends on the material and surface finish of the variant selected. For humid or mildly corrosive environments, consider variants with an anodized or coated finish. For harsh outdoor or wet conditions, consult the variant specifications or contact us to confirm suitability before ordering.

Yes. The AF-Type flanged pulley can be used as either the driving or driven pulley in a 5M belt drive system. Simply select the appropriate tooth count for each position based on your desired speed or torque ratio. Ensure both pulleys share the same belt pitch (5M) and belt width.