As one of the most important components of excavator, hydraulic pump is an energy conversion device that converts mechanical energy into hydraulic energy. Once the hydraulic pump fails, it will immediately affect the normal work of the hydraulic system of the excavator.
(1) Check the internal leakage of the boom cylinder. The simplest way is to raise the boom to see if it has obvious free fall. If the drop is obvious, disassemble the oil cylinder for inspection.
(2) Check the control valve. First, clean the safety valve, check whether the valve core is worn, and replace it if worn. If the safety valve remains unchanged after installation, check the wear of the control valve core.
(3) Measure the pressure of the excavator hydraulic pump. If the pressure is too low, adjust it. If the pressure still cannot be adjusted, the hydraulic pump is severely worn.
In general, the main reasons for boom failure to lift under load are:
a. The hydraulic pump of the excavator is severely worn. Serious leakage in the pump at low speed; During high-speed operation, due to wear and internal leakage of the pump, the volumetric efficiency drops significantly and it is difficult to reach the rated pressure. Long time operation of hydraulic pump aggravates wear and oil temperature rise, which causes wear of hydraulic components, aging and damage of seals, loss of sealing capacity, deterioration of hydraulic oil and finally failure.
b. The selection of hydraulic components is unreasonable. The seals are also non-standard, with high manufacturing cost and inconvenient seal replacement. The small cylinder diameter of the boom cylinder will inevitably make the system set pressure high.
c. The design of the hydraulic system is unreasonable. The hydraulic pump often works under full load or overload for a long time, and the system has hydraulic impact. The oil is not changed for a long time. The hydraulic oil is polluted, which aggravates the wear of the hydraulic pump and causes the pump shell of the hydraulic pump to burst.
In a word, when the hydraulic system breaks down, don't deal with it blindly. For the faults caused by the internal wear of components, first understand the principle and then make targeted inspections. Only through more in-depth understanding and mastering of the hydraulic system, and constantly improve the technology and working ability, can we better solve the main problems faced by hydraulic equipment users and manage the hydraulic system.
