The hydraulic system of a small rotary drilling rig is equivalent to the blood circulation system of the human body, and plays an irreplaceable role in the normal operation of the rotary drilling rig. The operator must have certain maintenance knowledge, and at the same time, he must carefully check the operation of the machine before starting work, and promptly understand the abnormalities of the machine's hydraulic system:
(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 it falls obviously, disassemble the cylinder for inspection, and replace the seal ring if it is worn.
(2) Check the control valve. First clean the safety valve and check whether the valve core is worn. If worn, it should be replaced. If there is still no change in the safety valve after installation, check the wear of the control valve core. The clearance limit is generally 0.06MM, and it should be replaced if it is severely worn.
(3) Measure the pressure of the hydraulic pump. If the pressure is low, adjust it. If the pressure cannot be adjusted, it means that the hydraulic pump is severely worn.
Generally speaking, the main reasons for the failure of the boom to lift with load are:
A. Severe wear of the hydraulic pump. When the pump is running at low speed, the internal leakage of the pump is serious; when the pump is running at high speed, the pump pressure is slightly increased, but due to the wear and internal leakage of the pump, the volumetric efficiency is significantly reduced, and it is difficult to reach the rated pressure. The long-term operation of the hydraulic pump aggravates the wear and the oil temperature rises, which causes the wear of the hydraulic components and the aging and damage of the seals, the loss of sealing ability, the deterioration of the hydraulic oil, and finally the failure.
B. The selection of hydraulic components is unreasonable. The specifications of the boom cylinder are 70/40 non-standard series, and the seals are also non-standard parts, with high manufacturing costs and inconvenient replacement of seals. The small bore of the boom cylinder is bound to make the system set pressure high.
C. The design of the hydraulic system is unreasonable. The control valve and the full hydraulic steering gear are single pumps in series, the safety valve set pressure is 16MPA, and the rated working pressure of the hydraulic pump is also 16MPA. The hydraulic pump often works under full load or long-term overload (high pressure), and the system has hydraulic impact, the hydraulic oil is contaminated, and the wear of the hydraulic pump is aggravated, resulting in the explosion of the hydraulic pump casing.
During the use of rotary drilling rigs, attention should also be paid to proper care and maintenance, regular filtering of hydraulic oil, maintenance of hydraulic oil cleanliness, and daily inspection and maintenance.
There are many hydraulic components on construction machinery, which require sufficient hydraulic oil. When the hydraulic oil deteriorates due to long-term use and needs to be replaced, some people mistakenly believe that it is only necessary to drain the oil in the hydraulic tank and fill it with new hydraulic oil. However, there is still a lot of old hydraulic oil left in the hydraulic oil pipe and hydraulic control valve. When the equipment is used, the mixing of new and old oils will accelerate the deterioration of the new oil.
Therefore, if you want the horse to run fast, you must let the horse eat more grass, and eat good grass. Therefore, normal maintenance of the machine is essential.
