EN
Proper tension is critical for the efficient, quiet, and long-lasting operation of synchronous belt drives, commonly used in engines, industrial machinery, and precision equipment. Incorrect tension—whether too loose or too tight—is a leading cause of premature belt failure, excessive noise, and bearing wear.
This guide provides a clear, methodical approach to achieving optimal synchronous belt tension, ensuring peak performance and reliability.
Why Correct Tension Matters
Too Loose: Causes belt slippage (even on teeth), loss of positional accuracy, excessive heat generation, and accelerated tooth wear.
Too Tight: Places excessive load on shafts and bearings, leading to overheating, reduced bearing life, and potential belt cord breakage.
Tools You Will Need:
Manufacturer's tension specifications
A belt tension gauge (deflection force or sonic type)
Basic hand tools (wrenches, Allen keys)
A straight edge or ruler (for deflection method)
The Recommended Tensioning Procedure:
1. Initial Installation & Setup
Ensure the drive is powered off and locked out. Install the new belt on the pulleys. Do not use excessive force or pry the belt on, as this can damage the cords. The belt should seat fully into the pulley grooves.
2. Apply Preliminary Tension
Loosen the motor or idler pulley's mounting bolts. Using the adjustment mechanism, move the pulley to apply a moderate initial tension to the belt. Tighten the mounting bolts just enough to hold position.
3. Measure and Adjust to Specification
This is the most crucial step. Use one of these two reliable methods:
Deflection Force Method (Most Common): Press the belt midway between two pulleys with a specified force (from the manufacturer). Measure the resulting deflection distance. Adjust the pulley until the deflection matches the specified value for your belt span length and type.
Sonic Tension Meter Method (Most Accurate): This device measures the belt's natural frequency when plucked. Input the belt's mass and span length. Pluck the belt and adjust the pulley until the meter reads the target frequency specified by the manufacturer.
4. Finalize and Verify
Once the correct tension is achieved, securely tighten all mounting bolts according to the manufacturer's torque specifications. Re-check the tension reading after final tightening, as it can sometimes shift.
5. Run-in and Re-check
New belts often experience a slight tension drop during the first 24-48 hours of operation (seat-in). It is good practice to re-check and slightly re-tension after this initial run-in period for a permanent setup.
Pro Tip: Always consult the specific technical manual for your drive system. Different belt profiles (e.g., GT2, HTD, T5) and materials have unique tension requirements.
For further information or technical support, please contact us.
