Mounting a pulley to a shaft is a critical power transmission application. The joint must withstand immense torque and shear forces from the belt, continuous rotational vibration, and heavy dynamic load without slipping (fretting). However, to minimize downtime during service, the pulley must be removably secured for replacement or adjustment.
The optimal solution is a retaining compound engineered for structural load transmission while offering easier serviceability than a permanent, high-strength bond.
INCURE WeldLock™ 338 Retaining Compound (Yellow)
The INCURE WeldLock™ 338 Retaining Compound is the functional “Medium Strength” solution. It is designed for press or slip-fit applications where future disassembly is required, providing excellent security against torque and vibration without demanding excessive force (or specialized heat treatment) for removal.
| Key Feature | Performance for Pulley-to-Shaft Mounts |
| Serviceable Bond (Yellow) | Designed for assemblies requiring removal or repositioning. Secures the pulley against slippage but allows for non-destructive removal when the pulley or shaft requires service. |
| Excellent Shear Resistance | Provides reliable holding power against the rotational forces transmitted by the belt, preventing the pulley from spinning on the shaft and causing fretting wear. |
| Gap Fill (Up to 0.25mm) | Effectively fills the annular space, eliminating play and ensuring the shaft and pulley act as a single unit, maximizing power transmission efficiency. |
| Temperature Resistance (150∘C) | Maintains integrity under the heat generated by friction and the power transmission process. |
Application Steps: Installing Pulleys to Shafts
For optimal performance and reliable retention of the pulley, follow these steps:
1. Surface Preparation (The Foundation)
- Clean: Thoroughly clean the shaft surface and the pulley bore. Surfaces must be free of all grease, oil, and old compound residue. Use an industrial cleaner or solvent (e.g., acetone) and wipe dry.
- Activate (If Needed): If using passive metals (like stainless steel) or if the ambient temperature is below 15∘C(59∘F), apply a chemical activator to the bond surfaces and allow it to flash off completely.
2. Product Application
- Apply: Apply a continuous, thin bead of WeldLock™ 338 around the full circumference of either the shaft or the internal bore of the pulley hub.
- Ensure Coverage: For optimal retention and sealing, ensure the adhesive completely wets the entire mating surface as the components slide together.
3. Assembly and Curing
- Assemble: Immediately slide or press the pulley onto the shaft. Ensure the components are aligned correctly before the compound fixtures.
- Wipe Excess: Remove any excess adhesive visible outside the joint immediately after assembly.
- Cure: Allow the assembly to fixture before handling (typically 10-30 minutes). Allow a full 24 hours for the compound to reach maximum strength before engaging the pulley in power transmission service.