What are the safety protection devices for cranes?

In order to ensure safe and reliable lifting work, the crane is equipped with a more complete safety device to protect the machine or alert the operator in case of accident, thus providing safety protection.

1. Each relief valve in the hydraulic system: It can suppress abnormal high pressure in the circuit to prevent damage of the hydraulic oil pump and motor and prevent overload.

2. Boom luffing safety device: When an accident occurs and the high-pressure hose or tubing in the boom luffing cylinder circuit bursts or cuts, the balance valve in the hydraulic circuit acts to lock the work from the lower cavity of the cylinder. The oil keeps the boom from falling, thus ensuring the safety of the work.

3. Boom telescopic safety device: When an accident occurs and the high-pressure hose or tubing in the boom telescopic cylinder circuit bursts or cuts, the balance valve in the hydraulic circuit acts to lock the working oil from the lower chamber of the cylinder. Make the hoist retract yourself to ensure the safety of the job.

4. Height limit device: After the hook rises to the specified height, it touches the limit weight and opens the travel switch. The â€œover-windingâ€ indicator light is on, and the hook is lifted, the boom is extended, and the crane is lifted. The arm is swayed to the same action to ensure safety. At this time, as long as the operating hook is lowered, the boom is retracted or the boom is raised (ie, operated to a safe side), the limit weight is released from the constraint, and the operation returns to normal. In special occasions, if you still need to do a slight over-winding operation, press the release button on the meter box, the action of the limit will be released, but the operation must be very careful to prevent accidents.

5. Leg locking device: When an accident occurs, the high-pressure hose or tubing leading to the vertical cylinder of the leg is broken or cut, the two-way hydraulic lock in the hydraulic system can block the pressure oil of the two chambers of the leg blocking cylinder, so that the branch The legs are not shrunk or pulled out to ensure the safety of the lifting work.

6. Lifting weight indicator: The lifting weight indicator is arranged on the side of the basic arm (ie, the right side of the operating room), and the operator can clearly observe when sitting in the operating room, and can accurately indicate the boom. The rated lifting capacity allowed by the crane at the elevation angle and corresponding working conditions.

7. Lifting characteristics table: It is set on the front lower wall panel of the control room. The table lists the rated lifting weight and lifting height for various arm lengths and various working ranges for inspection during operation. When lifting work, do not exceed the values â€‹â€‹specified in the table.