Magnetic Powder Clutch and Brakes

The magnetic powder clutch and brakes provided by our company have passed the CE certification. They are the supporting products for China's Jiuquan Satellite Launch Center.

Our company has a complete set of testing equipment, including the measurement system for torque, speed and power, ensuring the reliability of our products. We have passed the ISO9001:2000 quality management system certification and we strictly implement the national machinery industry standards, JB/T 5988-1992 and JB/T5989-1922.

Product Features
1. The torque changes linearly with the excitation current.
The torque is transmitted through the magnetic powder chain formed by an electromagnetic field. Under normal circumstances, the excitation current is in a linear relationship with the torque that it transmits within the range of 5-100% of the rated torque, which is shown in Fig. A. Therefore, by changing the excitation current, the torque can be easily changed.

2. The torque is independent of the slip speed when the excitation current is constant.
When the excitation current remains unchanged, the transmitted torque is independent of the slip speed between the transmission part and the driven member, i.e. there is no difference between the static torque and the dynamic one. (As shown in Fig. B) Therefore, a constant torque can be transmitted stably. If this feature is used in the tension control, users are able to accurately control and transmit the desired torque by only adjusting the excitation current, thus easily and effectively achieving the purpose of controlling the tension of the roll materials.

Due to the above features, the magnetic powder clutch and brakes are widely used for the unwinding and rewinding tension control in papermaking, printing, plastic, rubber, spinning, dyeing, wire and cable, metallurgy and other fields. The magnetic powder clutch can also be used for buffer starting, overload protection, speed regulation, etc., while the magnetic powder brake is also used for the loading and braking of transmission machinery.

Model Selection
1. Selection of magnetic powder clutch and brake is generally based on the maximum torque that is needed to transmit. In the meantime, make sure the actual slip power is less than the permissible slip power of the products.
The calculation formula is as follows.
Actual slip power P=2×3.14×M×n/60=F•V
M----actual operating torque, N•m
n----slip speed, r/min
F----tension, N
V----line speed, m/s
In the absence of speed change mechanism, the product of the maximum tension required to wind the material and the maximum winding radius should be smaller than the rated torque of the magnetic powder brake.
2. The selection of magnetic powder clutch is also relative to its position. Under the premise of matching slip power, a small product can be chosen if it is put in the high-speed end. This also reduces the cost. When the small product can not match and a larger product is needed, put it in the middle or rear of the transmission mechanism to increase the operating torque and reduce the slip speed.
3. Under certain cooling conditions, the slip power of the magnetic powder clutch or brake is fixed. Therefore, the actual torque and speed can compensate for each other, which means when the slip speed increases, the allowable torque will decrease correspondingly. But the maximum speed should not exceed the permissible value.

For example, there is a FZ100 magnetic powder brake, its rated torque M=100 N•m and the slip power P=7 KW
so the rated speed n=9550×P/M=9550×7/100=668.5 r/min
If the actual slip speed n=1500 r/min, the allowable torque M=9550×P/n=9550×7/1500=44.6 N•m
Note: The 9550 in the above formulas is a constant coefficient.

As a China-based magnetic powder clutch and brakes manufacturer and supplier, at Nantong Industrious we also offer elevator/escalator components, sound-proof rubber band, metalworking machinery and dies, busbar processing machine, and more.