What do we mean by the function of the hydraulic pump? It actually includes oil suction, oil pressure and oil regulation of hydraulic pump. Today, Yuanye Hydraulic will describe the following aspects:
Absorption oil pressure of hydraulic pump:
The oil suction and pressure of the spray hydraulic pump are completed by the reciprocating motion of the plunger in the plunger sleeve. When the plunger is in a lower position, the two oil holes on the plunger sleeve are turned over, the inner cavity of the plunger sleeve is connected with the oil circuit in the pump body, and the fuel quickly fills the oil chamber. When the cam pushes the roller of the roller body, the plunger rises. Starting from the plunger, it moves upward until the oil hole is blocked by the upper end face of the plunger. At this moment, due to the movement of the plunger, the fuel is squeezed out of the oil chamber and flows to the oil circuit. Therefore, this increase is called the pre stroke. When the plunger seals off the oil hole, it begins to squeeze the oil. When the plunger rises, the oil pressure in the chamber rises sharply. When the pressure exceeds the spring force and oil pressure of the outlet valve, the outlet valve is pushed open, and the fuel is pressed into the fuel pipe and sent to the fuel injector.
The time when the inlet oil hole on the plunger sleeve is completely blocked by the upper end face of the plunger is called the theoretical oil supply starting point. When the plunger continues to move upward, the oil supply continues and the oil pressure process continues until the spiral cone on the plunger is disengaged and the plunger returns to the oil hole. When the oil hole is opened, the high-pressure oil flows from the oil chamber to the oil passage in the pump body through the longitudinal groove on the plunger and the oil return hole on the plunger sleeve. At this time, the oil pressure in the plunger oil chamber drops rapidly, the outlet valve falls back to the valve seat under the effect of the spring and the oil pressure in the high-pressure oil pipe, and the injector immediately stops fuel injection. At this time, although the plunger continued to rise, the oil supply has now ended. The moment when the oil hole of the plunger is turned over by the bevel of the plunger is called the end of theoretical oil supply. In the whole process of upward movement of the plunger, only the middle stroke is the oil pressure process, which is called the effective stroke of the plunger.
Adjustment of hydraulic pump oil volume:
In order to meet the requirements of diesel engine load, the fuel supply demand of injection hydraulic pump is adjusted from large fuel supply (full load) to zero fuel supply (shutdown). The oil supply conditioning is realized by rotating all the plungers of the spray hydraulic pump together with the gear rod and the rotary sleeve. When the plunger rotates, the start time of oil supply will not change, while the end time of oil supply will change due to the change of the plunger orientation of the oil return hole of the bevel sleeve of the plunger. The effective stroke of the plunger will also be different with the different view points of the plunger and rotation, so the oil supply will also change.
The greater the viewing point of rotation of the plunger in non oil supply orientation 1, the greater the distance from the upper end face of the plunger to the bevel edge of the plug sleeve opening oil return hole, and the greater the oil supply. If the rotation viewing point of the plunger is smaller, the earlier the fuel cut-off starts, and the less fuel is supplied. When the diesel engine is shut down, the oil shall be blocked. For this reason, the longitudinal groove on the plunger can be turned to face the plunger and put back into the oil hole. At this time, during the whole plunger stroke, the fuel in the plunger sleeve always passes through the longitudinal groove and returns to the oil return passage of the oil hole. There is no oil pressure process, so the oil supply is equal to zero. When the plunger rotates, the fuel supply is adjusted by changing the timing of the end of the fuel supply. This method is called fuel supply end adjustment method. The oil supply of the hydraulic pump shall meet the requirements of the diesel engine under various working conditions. According to the requirements of the diesel engine, the hydraulic pump shall ensure that the oil supply starting time of each cylinder is the same, that is, the oil supply advance angle of each cylinder is the same, and the oil supply duration is the same. The oil supply shall be started quickly and stopped quickly and cleanly to avoid oil dripping. According to different combustion chamber types and mixture composition methods, the hydraulic pump needs to provide fuel with sufficient pressure to the injector to ensure excellent atomization quality.
Kunshan Yuanye Hydraulic is an enterprise integrating industrial equipment maintenance and skills, including hydraulic cylinders, hydraulic pumps, hydraulic tools, engineering hydraulics, air compressors, compressed air drying systems and metal repair. Both have rich experience in repair. Complete sets of industrial automation equipment can also be customized according to customer needs, and the price is very favorable! Transparent! Spend a penny and enjoy quality service. This is a company you can trust! We look forward to your call.