Word forms: (regular plural) brake drums
( Automotive engineering : Vehicle components , Brakes, steering, wheels, tires, and suspension ) brake1, brake2
A brake drum
is a closed cylinder
attached to a vehicle wheel, against which a brake shoe presses
to make the vehicle go slower
The inside surface of the brake drum must be smooth and uniform so that the brake shoe can be applied against it.
The brake shoes are forced by hydraulic wheel cylinders against the inner surface
of the rotating brake drum.
A drum brake system consists of hydraulic wheel cylinders, brake shoes, and a brake drum.
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