Magnetic particle clutches and brakes
MAGNECLUTCH Applications
​See below for MAGNECLUTCH engineering calculations on the following applications:​
Magnetic Particle Clutch on a Powered Rewind
Magnetic Particle Clutch for Overload Protection
Magnetic Particle Clutch for Dynamometer Testing
Magnetic Particle Clutch on a Powered Rewind
Web Force (F) = 3.5 lb.s
Web Speed (V) = 1490 fpm
Core Dia. (d) = 3.25 in.
Full Roll Dia. (D) = 16 in.
Motor Speed = 1750 rpm
1. Calculate Torque (T)
T = Force x Radius
T Start = 3.5 lbs. x 3.25in. / 24in. = 0.5 lb. ft.
T Finish = 3.5 lbs. x 16in. / 24 in. = 2.3 lb. ft.
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2. Calculate Speed (RPM)
RPM = Velocity / π(diameter)
RPM Start = 1490 fpm / π x 3.25in. / 12in. = 1750 rpm
RPM Finish = 1490 fpm / π x 16in. / 12in. = 356 rpm
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3. Calculate Slip Watts (SW)
SW = T x (RPM in - RPM out) / 7.04
SW Start = 0
SW Finish = 2.3 lb. ft. x (1750 rpm - 356 rpm) / 7.04 = 455 watts
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4. From Slip Watts vs RPM curves
The 10MC90B20 will dissipate 500 watts at 1750 rpm
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5. Select 10MC90B20
Magnetic Particle Clutch for Overload Protection
Torque Required at Conveyor (T Req) = 20 lb. ft.
Speed of Conveyor Drive Roll (N Req) = 175 rpm
Motor = 1 hp @ 1750 rpm
Gear Box Ratio = 10:1
1. Calculate Torque at Clutch (T)
T = T Req / Gear Ratio
T = 20 lb. ft. / 10 = 2.0 lb. ft.
2. Calculate Speed at Clutch (RPM)
RPM = N Req x Gear Ratio
RPM = 175 rpm x 10 = 1750 rpm
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3. Calculate Slip Watts (SW)
SW = T x RPM / 7.04
SW in normal operation = 0
SW when jam-up occurs: SW = 2.0 lb. ft. x 1750 rpm / 7.04 = 497 watts
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4. From Slip Watts vs RPM Curves
The 10MC90B20 will dissipate 500 watts at 1750 rpm
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5. Select 10MC90B20
Magnetic Particle Clutch for Dynamometer Testing
Test Motor Size = 1/4 - 1 hp
Full Load Speed = 1750 rpm
1. Calculate Torque (T)
T = 5250 x hp / rpm
T Min = 5250 x 1/4 hp / 1750 rpm = .75 lb. ft.
T Max = 5250 x 1 hp / 1750 rpm = 3 lb. ft.
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2. Calculate Slip Watts (SW)
SW = T x RPM / 7.04
SW Min = .75 lb. ft. x 1750 rpm / 7.04 = 186 watts
SW Max = 3 lb. ft. x 1750 rpm / 7.04 = 746 watts
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3. From Slip Watts vs RPM Curves
The 10MCA90B20 will dissipate 785 watts at 1750 rpm
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4. Select 10MCA90B20
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Quck Selection - Heat Dissipation (Slip Watts) vs Speed (RPM)
