Magnetic Drum Brake
Johnson Magnetic Drum Brakes are spring-applied, electrically-released DC drum brakes, available in metric (DIN standard, DA codes) and imperial (AISE standard, SMAA/MAA codes) dimensions, plus DQ (hydraulic pedal), DW (handwheel), and DR (lever applied) actuation variants. Fabricated steel mechanism with ductile iron brake shoes, non-ferrous bushed pivots, ground stainless steel pins, and high-temperature non-asbestos friction linings.
Applications: Mechanical handling equipment, cranes, winches, elevators, lifts, rolling mills, mixers and similar equipment.
Options: Self-adjusting mechanism to compensate for lining wear, mechanical release lever, limit switches to monitor release/set/wear, hydraulic override by remote pedal, and special materials/finishes including high-integrity nuclear specifications. Separate enclosed control units are available for DC or AC supplies.
SMAA Series — Imperial (AISE)
Drum Diameter: 6 in
Max Torque: 59 lb-ft
AISE Torque: 24 lb-ft
Weight: 62 lb
Coil Power: 90 W
Drum Diameter: 8 in
Max Torque: 160 lb-ft
AISE Torque: 100 lb-ft
Weight: 100 lb
Coil Power: 110 W
Drum Diameter: 10 in
Max Torque: 270 lb-ft
AISE Torque: 200 lb-ft
Weight: 140 lb
Coil Power: 170 W
Drum Diameter: 13 in
Max Torque: 630 lb-ft
AISE Torque: 550 lb-ft
Weight: 240 lb
Coil Power: 800/200 W
Drum Diameter: 16 in
Max Torque: 1100 lb-ft
AISE Torque: 1000 lb-ft
Weight: 540 lb
Coil Power: 1100/275 W
Drum Diameter: 19 in
Max Torque: 2620 lb-ft
AISE Torque: 2000 lb-ft
Weight: 815 lb
Coil Power: 2700/350 W
Drum Diameter: 23 in
Max Torque: 4000 lb-ft
AISE Torque: 4000 lb-ft
Weight: 1370 lb
Coil Power: 3500/450 W
MAA Series — Imperial
Drum Diameter: 8 in
Max Torque: 155 lb-ft (213 Nm)
Weight: 100 lb (45 kg)
Coil Power: 110 W
Drum Diameter: 10 in
Max Torque: 265 lb-ft (362 Nm)
Weight: 140 lb (64 kg)
Coil Power: 170 W
Drum Diameter: 14 in
Max Torque: 675 lb-ft (915 Nm)
Weight: 220 lb (100 kg)
Coil Power: 800/200 W
Drum Diameter: 18 in
Max Torque: 1245 lb-ft (1690 Nm)
Weight: 540 lb (245 kg)
Coil Power: 1100/275 W
Drum Diameter: 21 in
Max Torque: 2870 lb-ft (3900 Nm)
Weight: 815 lb (370 kg)
Coil Power: 2700/350 W
Drum Diameter: 24 in
Max Torque: 4200 lb-ft (5690 Nm)
Weight: 1370 lb (620 kg)
Coil Power: 3500/450 W
Drum Diameter: 30 in
Max Torque: 5420 lb-ft (7350 Nm)
Weight: 1672 lb (760 kg)
Coil Power (continuous): 585 W
Coil: Series wound, for DC hoist motors
Drum Diameter: 30 in
Max Torque: 8132 lb-ft (11025 Nm)
Weight: 2575 lb (1170 kg)
Coil Power (continuous): 676 W
Coil: Series wound, for DC hoist motors
DA Series — Metric (DIN)
Drum Diameter: 100 mm (4 in)
Max Torque: 32 Nm
Weight: 11 kg
Coil Power: 45 W
Drum Diameter: 160 mm (6 in)
Max Torque: 80 Nm
Weight: 28 kg
Coil Power: 90 W
Drum Diameter: 200 mm (8 in)
Max Torque: 213 Nm
Weight: 46 kg
Coil Power: 110 W
Drum Diameter: 250 mm (10 in)
Max Torque: 362 Nm
Weight: 64 kg
Coil Power: 170 W
Drum Diameter: 315 mm (12 in)
Max Torque: 565 Nm
Weight: 100 kg
Coil Power: 210 W
Drum Diameter: 315 mm (12 in)
Max Torque: 810 Nm
Weight: 110 kg
Coil Power: 800/200 W
Drum Diameter: 400 mm (16 in)
Max Torque: 1487 Nm
Weight: 246 kg
Coil Power: 1100/275 W
Drum Diameter: 500 mm (20 in)
Max Torque: 1900 Nm
Weight: 264 kg
Coil Power: 1100/275 W
Drum Diameter: 500 mm (20 in)
Max Torque: 3670 Nm
Weight: 370 kg
Coil Power: 2700/350 W
Drum Diameter: 630 mm (24 in)
Max Torque: 5885 Nm
Weight: 620 kg
Coil Power: 3500/450 W
DA Series — Imperial
Drum Diameter: 4 in
Torque (Int. 50%): 21.7 lb-ft
Torque (Cont. 100%): 14 lb-ft
Weight: 24.3 lb
Coil Power: 45 W
Drum Diameter: 6 in
Torque (Int. 50%): 54.2 lb-ft
Torque (Cont. 100%): 35 lb-ft
Weight: 61.7 lb
Coil Power: 90 W
Drum Diameter: 8 in
Torque (Int. 50%): 145 lb-ft
Torque (Cont. 100%): 75 lb-ft
Weight: 101 lb
Coil Power: 110 W
Drum Diameter: 10 in
Torque (Int. 50%): 246 lb-ft
Torque (Cont. 100%): 150 lb-ft
Weight: 141 lb
Coil Power: 170 W
Drum Diameter: 12 in
Torque (Int. 50%): 383 lb-ft
Torque (Cont. 100%): 245 lb-ft
Weight: 220 lb
Coil Power: 210 W
Drum Diameter: 12 in
Torque (Int. 50%): 550 lb-ft
Torque (Cont. 100%): 400 lb-ft
Weight: 220 lb
Coil Power: 260 W
Drum Diameter: 16 in
Torque (Int. 50%): 1010 lb-ft
Torque (Cont. 100%): 645 lb-ft
Weight: 542 lb
Coil Power: 350 W
Drum Diameter: 20 in
Torque (Int. 50%): 1290 lb-ft
Torque (Cont. 100%): 820 lb-ft
Weight: 582 lb
Coil Power: 350 W
Drum Diameter: 20 in
Torque (Int. 50%): 2500 lb-ft
Torque (Cont. 100%): 1500 lb-ft
Weight: 815 lb
Coil Power: 2700/350 W (with Economy)
Drum Diameter: 24 in
Torque (Int. 50%): 3990 lb-ft
Torque (Cont. 100%): 3000 lb-ft
Weight: 1365 lb
Coil Power: 3500/450 W (with Economy)
DR / DW / DQ Series — Lever, Handwheel & Hydraulic
Actuation: Lever applied
Drum Diameter: 6–28 in / 160–710 mm
Torque: 65–8,260 lb-ft / 88–11,200 Nm
Lever Effort: 22–950 lbf / 98–4,220 N
Weight: 26–705 lb / 12–320 kg
Sizes: DR-6 to DR-28 (metric DR-160 to DR-710)
Full dimensional drawings available on request.
Actuation: Handwheel applied
Drum Diameter: 6–30 in / 160–760 mm
Torque: 87–6,150 lb-ft / 118–8,340 Nm
Weight: 26–970 lb / 12–440 kg
Sizes: DW-6 to DW-30 (metric DW-160 to DW-760)
Full dimensional drawings available on request.
Actuation: Hydraulic applied — pressure by pedal stroke or line
Drum Diameter: 160–500 mm
Service Torque: 48–1,677 Nm
Emergency Torque: 170–2,824 Nm
Typical Pedal Effort: 89–267 N service / 133–400 N emergency
Pressure at Max. Torque: 520–1,330 kPa
Weight: 12–130 kg
Sizes: DQ-160 to DQ-500
Full dimensional drawings available on request.