Full definition
A tensioning pulley that relies on its own weight or attached counterweights to maintain constant belt tension automatically, without manual adjustment. The pulley is mounted on a carriage that moves vertically (or along an inclined track) under gravity, taking up belt slack as the belt stretches over time. Provides constant tension regardless of belt elongation, temperature changes, or load variations — superior to fixed screw take-ups for long conveyors. Typical applications: conveyor systems exceeding 30 m in length, bucket elevators, and heavy mining conveyors. Take-up travel: 1.5-3% of center distance for textile belts, 0.5-1% for steel cord belts. Weight calculation: W = 2 × required slack-side tension. Per CEMA 7th Edition guidelines. Guide structure (rails, channels) must ensure smooth, friction-free carriage travel. Pulley diameter must meet belt manufacturer minimum bending radius requirements.