1. Check whether the hydraulic pump of small concrete mixer can output hydraulic oil. If it is a new hydraulic pump and there is no hydraulic oil output, it may be that the pump body has casting defects (shrinkage cavity, sand hole, etc.), so that the oil suction cavity is connected with the oil pressure cavity and the oil pressure capacity is lost. It should be replaced by the manufacturer in time. If it is not a new hydraulic pump and there is no hydraulic oil output, it may be that the steering of the pump is not right and the parts are seriously worn or damaged, so it should be replaced in time.
2. If the hydraulic pump of small concrete mixer has oil output, check whether the relief valve works normally. If it is abnormal, it may be that one of the valves in the pressure oil circuit is stuck in the oil return position due to dirt or other reasons, resulting in a short circuit between the pressure oil circuit and the overflow circuit. It may also be that the pipe joint is loose, or some valves in the pressure oil circuit are seriously leaking, or the seals of the hydraulic cylinder and hydraulic Mada are damaged, resulting in serious leakage. The elimination method is to disassemble the relevant valve for cleaning, check the size of the sealing gap and various sealing devices, and replace the damaged sealing device.
3. If the output flow of the hydraulic pump of the small cement concrete mixer decreases significantly with the increase of pressure, and the pressure does not reach the specified value, it is due to the increase of the gap after the wear of the hydraulic pump. The elimination method is to measure the volumetric efficiency of the hydraulic pump, which can determine whether the pump can continue to be used. The parts with serious wear should be repaired or replaced.
4. The hydraulic system of small concrete mixer can establish normal pressure, but there is no pressure in some pipelines or hydraulic cylinders, which may be due to the blockage of pipelines, small holes or throttle valves, directional valves and other parts. At this time, it is necessary to check the pressure section by section and whether there is oil passing through, find out the cause and eliminate it.