Magnetic DC Voltage Drum Brake Spring applied / Electrically Released
Spring Set DC electrically Released Drum Brakes Industry Type General Industrial Code, Prefix: GDA Steel Industry Standard, Prefix: SDA High Integrity Nuclear,  Prefix: HDA Dimensions Metric as DIN standard code: DL Imperial as A.I.S.E. standard code: SMAA Also non-standard drum sizes and base fixings Construction  Fabricated steel mechanism  Ductile iron brake shoes  Major pivots non-ferrous bushed  All pins ground stainless steel (lubricators optional)  Friction linings high temperature non asbestos Magnet  -DC tractive type with encapsulated coil Special Options    Self adjusting mechanism (compensating for wear)  Mechanical release lever  Limit switches to monitor release/ set or wear  Hydraulic override by remote pedal  Special materials and finishes as required including high integrity specifications  Separate enclosed control units for DC or AC supplies Applications    Mechanical handling equipment, cranes, winches, elevators, lifts, also rolling mills, mixers etc. Engineering Design and selection assistance available	HDAQX250 DC Magnet Drum Brakes Shown here Nuclear Power Plant Application Note: This model includes Hydraulic override
Brake Selection The brake size must be chosen to give required braking torque and to dissipate the energy during stopping without over heating the drum. Brake torque is often related to drive motor torque by an arbitrary service factor typically 75% -100% full load torque for crane travel and similar inertial loads which tend to be self stopping or 150% -200% for crane hoists and other overhauling loads. If a precise stop time or distance is specified, then the brake torque must be calculated. Motor FL torque is given by:    - [(kW x 9550) / rpm]Nm or [(HP x 5250) / rpm]Lbft DIN Brake Model Data BRAKE MODEL DRUM DIA. "D" MAGNET SIZE TORQUE MAX. WEIGHT   mm   Nm kg GDA100 100 DA100 32 11 GDA160 160 DA160 80 28 GDA200 200 DA200 213 46 GDA250 250 DA250 362 64 GDA315 315 DA315 565 100 GDA400 400 DA400 1487 246 GDA500 500 DA500 1900 264 GDA630 630 DA630 5885 620	GDA500 General Duty DC Magnet Drum Brakes
AISE Brake Model Data BRAKE MODEL DRUM DIA. "D" MAGNET SIZE TORQUE MAX WEIGHT   in   Lbft Lb SMAA4 4 DA100 24 25 SMAA6 6 DA160 59 62 SMAA8 8 DA200 157 101 SMAA10 10 DA250 267 141 SMAA13 13 DAH315 626 220 SMAA16 16 DA400 1097 542 SMAA19 19 DAH500 2620 816 SMAA23 23 DA630 4000 1367 SMAA30 30 DA710 9000 1500
Magnetic Brake Actuator Data  Short stroke DC tractive type, all fabricated steel construction  Resin encapsulated coil with Class F insulation  Optional replaceable coil arrangement  100% continuously rated up to 40ºC  Airgap dust and drip protected by neoprene qaiter  Terminal Box IP55 standard enclosure Characteristics of DC Magnetic Drum Brakes All DC magnets tend to inherently show reponse due to build up and decay of the magnetic field.   The actual times are dependent on brake magnet size and vary with excitation voltage, coil temperature and spring loading (torque).  The magnet stroke which increases as the brake linings wear will also influence set and release times. Coil Forcing DC Magnets (Shunt wound voltage operated) Brake release and set times can be reduced by using an economy circuit.  This separate brake control unit will initially apply full voltage to release the brake magnet, after a set time period the circuit will drop voltage to only hold off the brake.  Control units are enclosed ventilated drip proof IP22 for DC supplies or totally enclosed IP55 with rectifier for 1 or 3 phase AC supplies. Series Wound DC Magnets (Current Operated, usually inline with motor drive) For use with crane rated DC series hoist motors to release the brake at 40% motor full load current and hold off at 10% current.

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