Hydraulic pump and oil motor operation and cover

Hydraulic pump and oil motor in the process of application inevitably occur failure, these failures can be divided into sudden and wear failure. Among them, the wear failure occurred in the late system work, the main if the parts due to natural wear and tear caused by damage to the system mostly expressed as failure of sealing information, the performance of agencies to slow the pace of activities, the impact The sudden failure often occurs in the early stages of system work and system work in the middle of the main if the administrator in the application and protection of the failure to operate the request and the rules caused by the damage caused by the system mostly For the tank cylinder burnout, the oil motor crawling phenomenon, the destruction of hydraulic components, hydraulic piping rupture and other malignant disorders, a great impact. The frequency of these malfunctions is intimately related to the black and white used and protected by everyday applications. In order to enable it to persistently maintain its outstanding working conditions and long service life, in addition to establishing and perfecting the daily protection system required to reduce the wear-out faults at the later stage, it is also necessary to prevent the initial and intermediate sudden Occurrence of disorders. 1, the system is always the status of the fluid Hydraulic pump has always been the subject of the idea that the hydraulic system caused by the culprit, because of space limitations, not repeat them here, only to make some personal exemplar topics. 1.1 hydraulic pump fluid viscosity should be appropriate, such as ZB-type pump recommended to change the viscosity with the oil temperature of the hydraulic oil, the viscosity range of 20 ~ 100cst less than the case temperature above 15 ℃, it is recommended to take a thick 40 a 2,30 No. 30 mechanical oil, hydraulic oil on the 30th machine, the situation temperature below 25 ℃, it is recommended to take YH-10 aviation hydraulic oil; domestic α and CB-4 gear pump, YB-type vane pump to adopt No. 20 mechanical oil. 1.2 adhere to the oil clean, maintain a certain degree of oil filter accuracy 1) axial piston pump end gap can take the initiative to compensate, the gap is small, thin oil film, oil filtration requirements of the highest. 2) Slanting disc axial piston pump oil filter accuracy of 10 ~ 15μm. 3) wear and tear caused by solid impurities, capacity and effectiveness of landing, leading to through-hole, variable bodies, parts, such as blockage and jamming. 4) once the oil pollution, should be more change, and clean with oil flushing. 1.3 Hydraulic oil pump oil temperature appropriate 1) - General working oil temperature should be 10 ~ 50 ℃, the maximum should be less than 65 ℃, local short-term should be less than 90 ℃. 2) Low temperature should be light or no load to start until the normal oil temperature and then resume normal operation. Generally by the temperature below 10 ℃, should be no-load operation 20min above ability to load: If the temperature is below 0 ℃ or above 35 ℃, should be heated or cooled; regional or winter start should make the oil temperature rose to 15 ℃ above can only be loaded; below -15 ℃ do not allow to start. 3) During work, it is forbidden to fill the hot components with cold oil, or to fill the cold components with hot oil, so as to prevent the temperature difference from being too large, inflating or sucking in different positions. In winter or cold areas, if the electric heater is used to heat the fuel tank, due to the pump and the motor is still cold, easy to die, the application should pay special attention. 2 guarantee the normal working conditions 2.1 hydraulic pump normal suction premise Although the hydraulic pumps are positive displacement pumps, there must be self-priming, but the friction seal surface mercury, self-absorption is limited, especially the internal pump manifold, The general height of the oil sump oil tank to the middle of the pump) is low, about 12 ~ 50cm, while some of the mercury expressly does not allow self-priming, such as ZB227 type, so should consider its inhalation premise, minimize inhalation resistance . 1) Suction tube shall not be equipped with a filter, or take a negative suction pump or auxiliary oil supply; 2) It is best to make the tank above the suction pump, or take auxiliary pump oil. Such as: ZB-type oil pump (except ZB227 type) at the rated turn (1500r / min) following the transfer, allowing self-absorption, but so will lead to a decline in capacity and rate of about 5%, and will inevitably affect its Application life expectancy, manufacturers generally do not recommend this application; most manufacturers recommend auxiliary pump oil, live by the pressure of about 0.7MPa. CY type oil mercury when operating at rated speed, allowing self-absorption, oil absorption height ≤ 500mm, at maximum speed operation, and the suction pipe (pipeline) is small, allowing the flow column height, oil absorption height of 300 ~ 500 mm, When the pipeline resistance is larger, the pump must take auxiliary mercury supply, supply pressure ≤ 0.4Mpa. 3) The suction pipe should be short and straight, and the pipe diameter should be slightly larger than the pump inlet. 4) suction pump suction valve should be fully open. Otherwise, it will cause ghosting and lowering of efficiency, which will seriously cause loss of suction. When the axial piston pump draws in the ball stroke, the plunger will be forcibly pulled out of the cylinder by force of the ball, thus easily destroying the ring hinge. 2.2 to ensure that the oil pump and motor oil drain pipe flow, generally do not answer the back pressure l) motor drain pipe should be single (dán) separate back to the tank, not allowed to connect with the back to the oil. 2) The external drain pipe should be covered with the pump and oil motor housing filled with oil to prevent parking when the oil tank back into the tank, such as the drain port is higher than the shell. 3) The general drain port is not connected to the back pressure, if the need to back pressure, its value should not exceed 0.16 ~ 0.20MPa, otherwise the hydraulic pressure will break the low pressure seal, such as shaft seal. 2.3 should ensure that the low-speed high-torque motor has enough back pressure l) curve-type oil motor in particular, pay attention to, back to back pressure should be 0.3 ~ 1.0MPa, the higher the speed, back to the oil back pressure should be greater, Otherwise, it will cause the roller to leave the stator guide rail surface and impact, shock, noise, serious damage. 2) The plunger pump that also serves as an oil motor should be supplied with sufficient oil pressure. If the hydraulic pump is in the descending condition of the regenerative speed limiter, the oil inlet will become the oil return port of the oil motor.