Magnetic Particle Brake

Overview

A magnetic particle brake works on the principle of magnetising a fine magnetic powder held in the gap between two rotating elements. When current is applied to the coil, the particles form chains that transmit torque between the elements; as the current rises, so does the braking torque. This design allows the torque to be adjusted precisely and steadily, even at low speeds. Because the torque is transmitted through the particles rather than by friction pads, it is applied to the roll smoothly and without interruption.

Magnetic particle brakes are used for tension control of unwinding material. They are available in two versions, with a shaft and shaftless (hollow-bore). The torque ratings are listed in the table below.

Features

• Braking torque adjusted by electric current
• Steady torque even at low speeds
• Shaft and shaftless (hollow-bore) versions
• Torque ratings to suit different roll weights
• Can be driven from the brake output of a tension controller

Applications

Magnetic particle brakes are used on the unwind stands of slitting, flexographic and rotogravure printing, laminating, paper, textile and plastics machinery. Used with a tension controller, the braking torque can be adjusted automatically as the roll diameter decreases, keeping web tension constant. The torque rating is chosen according to roll weight and the required tension.

Requesting a quotation

• Roll weight, with maximum and minimum roll diameter
• Line speed and the required tension range
• Shaft or hollow-bore preference and connection dimensions
• The controller that will drive the brake
• Quantity required

You can send your request through our contact page.