What a Bend Pulley Assembly Does
A bend pulley assembly is the package that changes the direction of a conveyor belt without driving it. It consists of a bend pulley, shaft, bearings, bearing housings, and a mounting arrangement that fixes the unit to the conveyor structure. In a typical configuration, the belt leaves the head or tail area, wraps partway around the bend pulley, and continues on a new line, which lets the conveyor follow a longer route or return the belt cleanly to the tail. Because the pulley does not transmit drive torque, its job is guidance and support rather than traction.
In a coal handling plant or a limestone quarry, this assembly is often found at the return side or at a transfer point where the belt must be redirected. It works alongside the conveyor belt, conveyor pulley, idler roller, and conveyor bracket, but it should not be confused with a drive pulley or a tail pulley. Each has a distinct role, and replacing one with another changes the conveyor layout and load path.
Construction and Key Components
The core is a cylindrical shell, usually welded steel, with end discs and a through shaft or stub shafts. The shell surface can be plain or covered with rubber, and the covering may be applied by hot vulcanizing, cold bonding, or casting. Diamond and herringbone patterns are common where extra grip or water shedding helps. Bearings sit in housings on both sides, and the assembly is fastened to the frame with bolts through a base plate or bearing bracket.
For sizing, the pulley face width is normally a little wider than the belt. Common references include B800 with a face around 950 mm, B1000 near 1150 mm, and B1200 near 1400 mm. Diameter and shaft size are chosen from belt tension, wrap angle, and bearing load, not from belt width alone. A B1200 x Ø1000 assembly may suit one layout, while a B800 x Ø500 unit may fit another; neither pairing is a rule.
| Parameter | Common reference values |
|---|---|
| Belt width | B400, B500, B650, B800, B1000, B1200, B1400, B1600 |
| Pulley diameter | Ø200, Ø250, Ø315, Ø400, Ø500, Ø630, Ø800, Ø1000 |
| Face width | Usually wider than the belt, e.g. B650 about 750 mm |
| Shaft diameter | Ø50, Ø60, Ø70, Ø80, Ø90, Ø100, Ø120, Ø140 |
| Surface | Plain, hot vulcanized rubber, cold bonded rubber, diamond, herringbone, ceramic |
| Cover thickness | 8, 10, 12, 15, 20 mm |
Where It Fits in a Conveyor Line
The assembly is used at points where the belt changes direction, such as a return bend, a take-up area, or a snub position. In a cement plant clinker line, it may guide the return strand around an obstacle. In a power station coal yard, it can help route the belt through a transfer house. It is also useful in sand and gravel plants, fertilizer handling, and tunnel muck removal, where space is tight and the belt must turn without a drive.
A comparison with a snub pulley is useful because both redirect the belt; the snub pulley usually increases wrap on a drive pulley, while the bend unit focuses on changing route direction. A tail pulley, by contrast, is located at the loading end and often includes tensioning. These are different subtypes, and the article remains about the bend assembly.
Buyer Checklist
- Confirm the actual belt width and the required face width, allowing for belt tracking.
- State the wrap angle and belt tension so the shaft and bearings can be sized correctly.
- Choose the surface based on material: plain for clean running, rubber or ceramic where slip and wear are concerns.
- Check the mounting interface, including bearing housing centers and conveyor bracket dimensions.
- Ask for the balancing grade and inspection record for higher-speed applications.
- Plan maintenance access for bearing lubrication and belt inspection.
During installation, align the assembly square to the belt centerline and check that the belt enters and leaves without rubbing. After startup, watch for belt drift, abnormal noise, and bearing temperature rise. A well-matched bend pulley assembly keeps the conveyor belt on track and reduces wear on the idler roller and conveyor pulley set.
