Buy Idler Pulleys Online in Australia
V-Belt Idler Pulley Selection — Quick Reference
Idler pulleys tension + back-bend belt drives. Correct selection + placement determines belt tension, drive smoothness, and service life. Inside vs outside idler placement changes which face of the belt is engaged.
| Idler Type | Belt Engagement | Best For |
|---|---|---|
| V-Groove Idler (A / B / C / B-C / 5V section) | Top face of V-belt (outside tensioning) | Standard tensioner placement on outside slack-side |
| Single-Row Bearing Idler | Per section | Most applications — light to medium radial load |
| Double-Row Bearing Idler | Per section | Heavily loaded drives — higher radial capacity |
| 4-Point Heavy Duty Idler (A / A-B / A-B-C section) | Per section | Demanding industrial drives — highest load capacity |
| Flat Flanged Idler — Single Bearing | Flat BACK of belt (inside tensioning) | Inside back-bend tensioner placement |
| Flat Flanged Idler — Double Bearing | Flat BACK of belt | Heavier load inside-tensioning applications |
| Composite / Polyurethane Idler | Per section | Quieter operation, longer belt life — premium choice |
Sizing rule: Idler diameter ≥ minimum recommended pulley diameter for the belt section (back-bend on smaller idlers shortens belt life). Placement: outside idler on slack side of drive (between driven pulley + driver, on slack side). Inside idler on slack side, back-bending the belt. Brands: Aetna, Don Dye, Gates. Companion: belts, pulleys, V-belts, V-belt size chart.
V-Belt Idler Pulleys
AIMS Industrial stocks V-belt idler pulleys and flat idler pulleys from Aetna, Don Dye and Gates for tensioning and back-bending belt drive systems. Correct idler selection and placement is essential for achieving design belt tension, minimising belt stress and maximising drive service life.
V-Groove Idler Pulleys
V-groove idler pulleys in A, B, C, B/C and 5V section engage the top face of the belt to provide outside tensioning. Single row bearing idlers are standard for most applications; double row bearing variants handle higher radial loads on heavily loaded drives. 4-point heavy duty idlers in A, A/B and A/B/C section provide exceptional load capacity for demanding industrial drives.
Flat Idler Pulleys (Flanged)
Flat flanged idler pulleys act on the flat back of the belt to provide inside tensioning. Available in single and double row bearing configurations, zinc plated and plain finishes, and OD sizes from 2-7/8" to 8". Extra heavy duty flanged variants handle high belt tensions on large industrial drives where standard pulleys would be marginal.
Flat Idler Pulleys (Non-Flanged)
Non-flanged flat idler pulleys are used where belt tracking is controlled by the drive geometry rather than the idler flange. Available in single and double row bearing configurations. Gates flat idler pulleys in 4.25" OD are available in 1.25" and 2.00" ID for direct shaft mounting.
Don Dye Idler Pulleys
Don Dye A/B section flat flanged idler pulleys in 4" and 5" OD are a robust option, available in single row and one-side plain steel configurations for drive designs requiring a specific contact surface finish on one face.
Application Notes
Outside idlers (V-groove) should be placed on the slack side of the drive with a larger diameter than inside (flat back) idlers to minimise belt bending stress. Avoid placing idlers close to the drive pulleys where belt wrap would be significantly reduced. Contact our team for drive design guidance.