26 models covering carrying, return, impact, tracking and self-cleaning duties. Machined, welded, sealed and tested in our own plant — diameter 50–219 mm, length 190–3400 mm, matched to your frame and belt width.
Most idler failures trace back to three things: bearing contamination, tube runout, or a coating that was never matched to the site. Here is how we build against each.
| Parameter | Specification |
|---|---|
| Roller diameter | 50 – 219 mm (2½" – 8⅝") |
| Roller length | 190 – 3400 mm, matched to belt width and frame |
| Speed rating | Rated life published at the CEMA basis speed of 500 rpm. 600 rpm is the general limit; beyond it we increase the diameter or move to a higher-grade design. Up to 750 rpm only on designs rated for it (BOS 613). Tell us your belt speed and we will confirm the diameter — see the speed-to-diameter matrix |
| Life rating (CEMA) | CEMA-classed. Minimum L10 life at the 500 rpm basis: CEMA B / C — 30,000 hours, CEMA D / E / F — 60,000 hours. Name the class your specification calls for and we build to it — the whole basis is explained in our CEMA life class guide |
| Idler tube | Q235 steel — equivalent to SS400 / JIS G3101 / EN 10025 / ASTM A36 |
| Idler shaft | 45# steel — equivalent to DIN C45 / EN C45 / JIS S45C / AISI 1045 |
| Bearing | Deep-groove ball bearings, single or double row, 2RZ / 2Z options — HRB or ZWZ as standard build, SKF / FAG where your specification names them. C3 clearance standard; C4 for clinker, sinter, coke and other high-temperature duty |
| Sealing system | Grease-retaining inner seal + multi-stage labyrinth + retention cap |
| Lubrication | Lithium / semi-synthetic grease with rust inhibitors — continuous service −40 °C to +120 °C; lithium complex to +160 °C for high-ambient duty |
| Welding | Mixed-gas shielded arc welding for consistent weld penetration |
| Surface treatment | Standard paint · hot-dip galvanizing · electrostatic (powder) coating · baking finish |
| Standards | GB / DIN / JIS / BS — exceeding GB/T 10595-2009 benchmarks |
| Traceability | Unique ID tag per unit, full lifecycle traceability |
| Custom options | High temperature · heavy load · corrosive · abrasive duty; stainless, UHMWPE, nylon, HDPE, polyurethane, rubber |
Carrying-side support, 20°/35°/45° trough angles.
Flat carry and return duty, standard and heavy-wall tube.
Rubber-ring cushioning at the loading point.
Absorbs impact energy, protects belt and splice.
Self-cleaning, guides belt and sheds carry-back.
Self-cleaning discs reduce material build-up.
Automatic belt tracking without external power.
Flexible linked rolls for high-impact loading zones.
Complete idler sets pre-assembled to your frame.
Reinforced builds for high load and transition zones.
Polymer shell for corrosion and build-up resistance.
Lightweight, low-noise, non-marking.
High abrasion resistance with quiet running.
Noise-sensitive sites and indoor plants.
Food, chemical and wash-down environments.
Curve and transition applications.
Gravity and powered conveyor duty.
Grip and cushioning applications.
Carry, return and friction configurations.
High-capacity carrying frames.
Tracking control on long transfers.
Standard carbon-steel builds in all diameters.
In cement plants and mines, bearings rarely wear out — they get contaminated. Our sealing stack is designed to keep dust and water out of the bearing housing for the full duty cycle.
The result is lower rotational resistance, less belt wear, and fewer change-outs — the metric your maintenance team is actually judged on. For the reasoning behind the clearance class and the grease temperature range, see our bearing and grease specification, and why idler bearings seize before they wear out.
Carrying, return, impact or tracking — and how abrasive is the material? Abrasive fines call for heavier wall tube and reinforced seals.
Salt spray, high temperature, acid/alkali or wash-down decide the shell material and the coating — galvanized, epoxy, powder or stainless.
If change-out means stopping the line, buy on service life, not unit price. We will quote both options side by side.
Send belt width, trough angle, material and duty. We will specify the idler, quote within 24 hours, and ship samples in 2–3 days.
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