Practice of disassembling, installing and adjusting electromagnetic brakes

Positional load protection - Brake clearance adjustment - Marine machinery maintenance

I. Structure and Principle of Disc Type Electromagnetic Brake

A disc type electromagnetic brake is an appliance that converts electromagnetic force into mechanical braking torque, thereby causing the motor to stop quickly after a power failure, as shown in figure 19-10. Most motors towing potentiodynamic loads have brakes, such as cargo lifters, anchors, and davits.

Figure 19-10 Disc Electromagnetic Brake Outline and Structure Diagrams

1. Components

Disc type electromagnetic brake consists of electromagnet, spring, brake pads (brake friction pads), electromagnet disc and so on.

2. Principles of operation

When working, the electromagnet is energized, attracting the electromagnet disc to overcome the spring force to open the brake, and the motor runs. When stopping, the electromagnet is de-energized and released, and the spring presses the electromagnet disc and brake friction plate to brake.

Measurement and Adjustment of Electromagnetic Brake Clearance

1. Measurement of gaps

(1) Scope of the criteria:The permissible clearance of the electromagnetic brake should be 0.6~2mm。

(2) Coil power-off status:Measure the gap between the solenoid disk and the end face of the solenoid core.

(3) Coil energized state:Measure the clearance between the brake friction pads and the solenoid disk and both sides of the rear end cap.

(4) Measurement methods:Measuring point is generally selected through the brake lifting screw as the measuring hole, with a plug ruler to measure separately, and then take the average value.

2. Gap adjustment

After measuring in the above manner, the gap is adjusted based on the measurement results in the following manner:

(1) Electromagnet disk and core end face gap adjustment:
It is adjusted by the adjusting screw on the solenoid disk. Tightening the adjusting screws inwards reduces the gap, i.e. reduces the friction; conversely, it increases the friction.

(2) Adjustment of clearance between friction plate and disc and both sides of rear end cap:
It is adjusted by the adjusting screw on the end face of the solenoid core. Tightening the adjusting screw inward is to reduce the gap, i.e., to increase the friction; conversely, to reduce the friction.

(3) Handling of brakes that won't open:
When the brake does not open, loosen the screws on the end face of the disc electromagnetic brake to increase the gap between the two sides of the friction pads. Adjust evenly.

🌟 Final commissioning criteria:
The appropriate clearance is 0.6 to 2 mm to satisfy that the loader can be braked without smoking when lifting the rated load.