(1) all kinds of driving devices should achieve the original design of the function, the "empty travel" to the brake lever system should not exceed 10% of the rated travel of the electromagnet.
(2) when the brake is released, the clearance between brake shoe and brake wheel shall be basically equal, and the maximum opening of the brake belt (unilateral) shall be ≤ LMM.
(3) the actual contact area between brake belt friction gasket (brake skin) and brake wheel should be greater than 70% of the theoretical contact area.
(4) the movable pin shaft of the brake shall rotate flexibly, without any phenomenon of abdication, jam, rust death and so on.
(5) the surface of the small shaft or mandrel of the brake shall be quenched and shall not be replaced by ordinary bolts;
No oil stains or other defects are allowed on the surface of the friction pads and brake wheels.
(6) if the brake has one of the following conditions, the part shall be scrapped:
A. cracks in lever, tie rod, brake arm or sleeve plate.
B. The spring has plastic deformation or fracture.
C. The thickness of the friction piece of the brake belt has been worn up to 50% of the original thickness, and the depth of the countersunk head of the rivet head is less than 50% of the thickness of the friction piece.
D. Pin or hole wear up to 5% of original diameter.
(7) the brake wheel shall be scrapped or disposed of under any of the following circumstances:
A. crack.
B. The convex and concave of the wheel surface ≥1.5mm shall be re-lighted;
When the thickness of the brake wheel rim of the hoisting and luffing mechanism is worn up to 40% of the original thickness, and when the wear of the brake wheel rim of other mechanism is worn up to 50% of the original thickness, the brake wheel shall be scrapped.
(8) the hoisting mechanism shall be equipped with two sets of brakes for hoisting cranes carrying hot metal, inflammable and explosive goods or slipping hook phenomenon that may cause great danger or loss.
(9) single or double brake lifting mechanism, each set of brakes must reliably stop 1.25 times the rated load.
(10) the braking torque shall be adjusted to obtain the appropriate braking interval:
A. Braking interval S of the lifting mechanism =[1/80 (heavy stage), 1/100 (intermediate stage), 1/120 (light stage)]×V l;
V liter is the lifting speed.
B. The braking interval of the large vehicle operating mechanism is about V / 1.5m/main, and V refers to the rated speed of the operating mechanism.
The crane with crane brake interval is 6 ~ 1lm and the crane with single beam is 2 ~ 6m.
C. The braking interval of the trolley running mechanism is about V / 20m/min, and 0.5 ~ 5m is more suitable.
