Full definition
Device that decelerates, stops, or holds stationary the rotary motion of industrial machinery. Types: shoe (external contracting, for cranes), disc (caliper or full-disc, for high-energy stops), band (wrapping around drum, for winches), electromagnetic (fast-cycling, for servo and conveyor), and hydraulic (high-torque, for presses and mills). Fail-safe (normally closed, spring-applied) designs are mandatory for cranes, elevators, hoists, and vertical conveyors per ASME B30.2 and EN 13135. Selection based on torque to be absorbed, kinetic energy (½Iω²), duty cycle, and thermal capacity. Friction materials: organic, sintered, or ceramic. Response time: 15-200 ms. Brands: Stromag, Svendborg, Pintsch Bubenzer, Eaton Airflex. Periodic inspection of lining wear and air gap is critical.