When using the elongated arm of excavator, the output flow of gear pump is insufficient to absorb oil, which affects the normal operation of equipment. Therefore, many people want to know what happened here, and the reason for these phenomena is summarized in the small edition of the extended arm excavator.
The output flow of gear pump is insufficient, or the gear pump does not suck oil means that the gear pump works under the drive of motor, but the displacement flow of gear pump is very small and can not reach the rated flow. In hydraulic system, the speed of cylinder or oil motor becomes slower, and the speed of battery filling becomes slower. Accumulator charging pressure increases for a long time, control valve response slow and other faults.
The reasons why the output flow of the gear pump of the elongated arm excavator is insufficient to absorb oil are as follows:
1. The blockage of the filter at the injection port leads to the increase of oil absorption resistance and suction. At this time, it is necessary to remove the filter for cleaning, and to analyze the causes and types of sewage. This can not only prevent the suction of oil in gear pump, but also prevent the causes of other faults.
2. The serious strain of the sliding contact surface between the gear end face and the front and rear cover leads to excessive internal leakage, resulting in reduced output flow. One of the main reasons for the tension is that the burr on the gear profile has not been carefully removed before assembly and the surface of tension joint after operation. Secondly, the dirt wedges into the sliding gap between the gear end face and the front and back cover of the pump, which produces strain on the mating surface. It can be seen from the figure that the strain of the high and low pressure cavity is connected through the groove, which leads to the decrease of the output flow, which is very common. At this time, the gear pump should be disassembled, and the end face of the front and rear cover gear should be grinded with the plane, and the burr shape (but not chamfer) on the teeth should be removed. The size of the unloading groove after the front and rear cover face before and after the plane grinding will change. It should be deepened and broadened appropriately.
3. Because of poor processing or assembly, the two bearing holes before and after the axle line cover not parallel (oblique). The eccentric wear of the two gear axles is similar to the tension line of the front and rear cover of the end, but it is not a complete circle (sector-shaped circular surface), resulting in increased internal leakage. At this time, the treatment is the same as above.
4. Radial unbalanced force causes gear shaft deformation, friction pump body cavity, increase radial clearance, and increase internal leakage.
5. The oil temperature is too high, the temperature rise reduces the oil viscosity, and the increase of internal leakage reduces the crude oil production. Find out the cause of high oil temperature and take corresponding measures. On high and medium pressure gear pumps, check whether the bow seal ring is damaged.
6. If the selected oil viscosity is too high or too low, the excessive viscosity will increase the oil absorption resistance; if the viscosity is too low, the leakage will be large. Oil with suitable viscosity should be selected according to the instructions for the use of oil pumps.
7、CB - B齿轮泵是非正负压泵(除非指定顺序)，当泵方向不对时，吸油量或流量非常小，此时应检查电机转向。
7. CB-B gear pump is a non-positive and negative pressure pump (unless specified in order). When the direction of the pump is not right, the oil absorption or flow rate is very small. At this time, the motor steering should be checked.
8. After disassembly and repair, the pump body is installed in reverse direction. At this time, the pressure oil of pressure chamber P flows to the oil suction zone O along the unloading groove e e of the pump body, resulting in short local connection, greatly reduced flow, and the pump body can not be inverted.
9、电机转速不够，CB - B齿轮泵额定输出流量按电机转速1450rpm计算，低于此数，流量减少。
9. The motor speed is not enough. The rated output flow of CB-B gear pump is calculated according to the motor speed of 1450 rpm, which is lower than that, and the flow rate decreases.
10. The pump shaft is broken. The motor drives the pump on the surface, but there is no oil at all. At this time, the pump shaft should be replaced.
Above is the reason why the output flow of gear pump of elongated arm excavator is insufficient to absorb oil production, which will help you to solve this problem.