Full definition
The force applied to a power transmission belt to maintain adequate contact pressure between belt and pulley grooves, enabling friction-based power transmission. Correct tension is critical: insufficient tension causes slippage, heat buildup, squealing, and rapid wear; excessive tension overloads shaft bearings, accelerates belt fatigue, and wastes energy. For V-belts, proper tension typically creates a specific deflection (1/64" per inch of span length) under a known force, or a target natural frequency (Hz) per manufacturer tables. Initial tension on new belts should be 1.3-1.5x normal operating tension to compensate for run-in stretch. Retension after 24-48 hours of operation. Measure with a sonic frequency meter (Gates 508C, Optibelt TT3) or force-deflection gauge (Krikit). Per ISO 1081 and manufacturer specifications. Belt tension accounts for 30% of maintenance-related belt failures.