- Oct 18, 2017 -
The reason and diagnosis of the deviation and dragging of the brake
In the process of crane operation, the braking deviation is mainly due to the different braking effects of the left and right wheels or track chassis on the same axle, so that the vehicle's braking is offset to one side. The main reason is generally the difference between the left and right shoe piece and the brake hub and the brake block adjustment is not consistent with the brake wheel clearance, or because of the oil pollution and hardening of the individual hoofs, the rivet and the loss circle of the brake hub, the two brakes fail to match. During the trial run, it is not difficult to find out the brake failure tire (track) from the deviation direction of the vehicle wheel and the tire trailing marks during the trial run. By further examination, we can find out the specific reasons, and then we can get rid of the trouble.
After the brake is stopped, the brake shoe (brake block or belt) bites with the brake hub (wheel), causing the difficulty of restarting is called brake lag. In this case, the vehicle or working device is not easy to accelerate, and the brake hub (wheel) will be seriously hot. For the wheel chassis using the pneumatic brake, if all the wheels are bitten, the failure is mostly from the failure of the brake valve, such as the broken of the valve spring. The valve closed, the brake release after high pressure air can not be discharged, the brake can not lift.
The hydraulic brake is usually the free travel of the brake pedal too small or the back of the oil hole, so that the brake fluid can not be released when the brake pedal is released. When checking, the lid of the main pump reservoir can be opened. After stepping down the brake pedal, slowly lift it up and observe the oil return. If no oil is returned, it means that the free travel is too small or the oil return is blocked. For brakes with electromagnetic braking, the failure of relay that can not be quickly cut off should be excluded.