To ensure the safety and reliability of lifting operations, the crane is equipped with comprehensive safety devices, which can protect the components or alert the operators to pay attention in case of an accident, thereby providing safety protection. 1. Each relief valve in the hydraulic system: It can suppress abnormal high pressure in the circuit to prevent damage to the hydraulic pump and motor, and prevent overload conditions. 2. Lifting arm amplitude safety device: In case of an unexpected accident, when the high-pressure hose or pipe in the lifting arm amplitude oil circuit bursts or is cut, the balance valve in the hydraulic circuit will come into action, locking the working oil from the lower chamber of the oil cylinder, preventing the lifting arm from falling, thus ensuring the safety of the operation. 3. Lifting arm extension and retraction safety device: In case of an unexpected accident, when the high-pressure hose or pipe in the lifting arm extension and retraction oil circuit bursts or is cut, the balance valve in the hydraulic circuit will come into action, locking the working oil from the lower chamber of the oil cylinder, allowing the lifting arm to retract itself, thus ensuring the safety of the operation. 4. Height limit device: When the hook rises to the specified height and touches the limit weight, the limit switch is opened, the "overturn" indicator light is on, and the operation of raising the hook, extending the arm, and lowering the arm to the side is cut off to ensure safety. At this time, when operating the handle such as lowering the hook, retracting the arm, or raising the arm (i.e., operating in a safe direction), the limit weight releases the constraint, and the operation returns to normal. In special cases, if a slight overturn operation is still required, the release button on the instrument box can be pressed. At this time, the limit function is released, but the operation must be very cautious and careful to prevent accidents.
5. Leg locking device: In case of an unexpected accident, when the high-pressure hose or pipe leading to the vertical oil cylinder of the legs bursts or is cut, the bidirectional hydraulic lock in the hydraulic system can block the pressure oil in both chambers of the leg locking oil cylinder, preventing the legs from retracting or swinging out, thus ensuring the safety of the lifting operation.
6. Lifting capacity indicator: The lifting capacity indicator is set on the side of the basic arm (i.e., the right side of the control room), and the operator can clearly observe it while sitting in the control room, accurately indicating the elevation angle of the lifting arm and the rated lifting capacity allowed by the crane under corresponding working conditions.
7. Lifting characteristic table: It is set on the lower wall panel of the front side of the control room. This table lists the rated lifting capacity and lifting height under various arm lengths and working amplitudes, for reference during operation. During lifting operations, it is not allowed to exceed the values specified in the table. To ensure the safety and reliability of the lifting operation, the crane is equipped with comprehensive safety devices, which can protect the components or alert the operators to pay attention in case of an accident, thereby providing safety protection.
