Multi-station hydraulic pump test bed and oil temperature control system thereof

Abstract

The oil temperature control system comprises a hydraulic oil tank, a controller, an oil tank cooling loop, an oil tank circulation loop and a station temperature sensor, the hydraulic oil tank is divided into a hot oil area and a cold oil area, an oil suction port of the oil tank cooling loop is arranged in the hot oil area, and an oil outlet of the oil tank cooling loop is arranged in the cold oil area; the oil tank cooling loop is used for cooling oil in the hot oil area and conveying the oil to the cold oil area; the oil tank circulating loop is used for circularly mixing the oil on the upper layer and the lower layer of the cold oil area; the controller is used for adjusting the cooling efficiency of the oil tank cooling loop according to data of the station temperature sensor. The oil suction port of the oil tank cooling loop is formed in the hot oil area, oil in the hot oil area is cooled and then flows back to the oil tank cold oil area, and the overall temperature of the oil tank is uniform. An oil tank circulation loop is arranged in the oil tank cold oil area and pumps cold oil on the lower layer of the oil tank to the upper layer of the oil tank in the cold oil area, and temperature uniformization of the cold oil area is accelerated.

Description

Technical Field

[0001] The utility model belongs to the technical field of hydraulic testing, and in particular relates to a multi-station hydraulic pump test bench and an oil temperature control system thereof. Background Art

[0002] The hydraulic pump test bench is an important equipment to verify the performance of hydraulic pump products and is a necessary equipment for hydraulic pump factory testing. Its key test indicator is volumetric efficiency. It is necessary to test the flow value of the hydraulic pump at various specific speeds and specific pressures (the oil discharged by the hydraulic pump per unit time), and obtain the volumetric efficiency value through the flow value of the specific pressure / the flow value of the no-load pressure. The flow value is closely related to the oil temperature. As the oil temperature increases, the viscosity of the hydraulic oil decreases, and the leakage through the hydraulic pump fit clearance increases under the same pressure. The hydraulic pump outlet flow decreases, and its volumetric efficiency under the same pressure and speed decreases. Generally, the factory test requires the hydraulic pump inlet oil temperature to be controlled at 50℃±4℃, and requires the oil pump to be greater than a certain value at the rated working speed and pressure point before it is allowed to leave the factory. If the oil temperature is not within this range, the volumetric efficiency data value tested is not the real data, and there is a possibility that unqualified products are mistakenly shipped out of the factory, and qualified products are judged as unqualified.

[0003] Due to the large number of hydraulic pump specifications and large displacement, the oil tank is relatively large and contains more oil. In particular, in order to save costs, the multi-station hydraulic pump test bench system shares the hydraulic oil tank, cooling system and temperature control system. Although most of the existing hydraulic pump test benches have cooling circulation systems and loading test circuits, due to the large density of cold hydraulic oil and the small density of hot oil, the cold oil sinks to the bottom of the oil tank and the hot oil floats on the upper layer. Although there is a cooling circulation system circulating in the hot oil area and the cold oil area of ​​the oil tank, there is obviously an imbalance in the oil temperature of the corresponding suction tank area of ​​the two-station tested pump. At present, most of the hydraulic pump test bench oil temperature sensors are installed on the hydraulic oil tank near the suction filter side, but the actual oil inlet temperature of the hydraulic pump is different from the oil tank temperature. In addition, due to the difference in installation position in the double-station system, if the oil tank temperature is uneven, it will cause the problem of inconsistent oil temperature during testing at each station. Moreover, most hydraulic pump test benches use switch temperature control: the cooling system is turned on after the upper temperature limit is reached, and the cooling system is turned off after the temperature reaches the lower limit. Due to the time delay of the oil temperature, the oil temperature exceeds the upper and lower limits, and the oil temperature control effect is not good. Summary of the invention

[0004] To this end, the utility model provides a multi-station hydraulic pump test bench and an oil temperature control system thereof to solve the technical problems mentioned in the background technology.

[0005] A technical solution of the utility model is as follows: an oil temperature control system of a multi-station hydraulic pump test bench, comprising: a hydraulic oil tank, a controller, an oil tank cooling circuit, an oil tank circulation circuit and a station temperature sensor, the hydraulic oil tank is divided into a hot oil area and a cold oil area, the oil suction port of the oil tank cooling circuit is arranged in the hot oil area, the oil outlet is arranged in the cold oil area, one end of the oil tank circulation circuit is arranged in the upper part of the cold oil area, and the other end is arranged in the lower part of the cold oil area, the station temperature sensor is installed in the oil inlet pipeline of each test station, and the controller is respectively connected to the oil tank cooling circuit and each station temperature sensor;

[0006] The oil tank cooling circuit is used to cool the oil in the hot oil area and transport it to the cold oil area, and the oil tank circulation circuit is used to circulate and mix the oil in the upper and lower layers of the cold oil area to make the temperature of the cold oil area uniform;

[0007] The controller is used to adjust the cooling efficiency of the oil tank cooling circuit according to the data of the station temperature sensor to ensure that the temperature of the oil in the oil inlet pipeline entering the test station is within a preset temperature.

[0008] Furthermore, the oil tank cooling circuit includes: a cooling oil pump, a water cooler and an electromagnetic proportional valve. The oil suction port of the cooling oil pump is placed in the hot oil zone, the oil outlet of the cooling oil pump is connected to the oil inlet of the cooler, the oil outlet of the cooler is placed in the cold oil zone, a cooling medium is passed through the cooler, the cooling medium inlet of the cooler is connected to the electromagnetic proportional valve, the electromagnetic proportional valve is connected to a controller, and the controller is used to adjust the opening of the electromagnetic proportional valve according to data from the workstation temperature sensor.

[0009] Furthermore, filters are provided at the oil suction port of the cooling oil pump and the oil outlet of the cooler.

[0010] Furthermore, the oil tank circulation loop includes a circulating oil pump, the oil suction port of the circulating oil pump is arranged at the upper part or the lower part of the cooling zone, and the oil outlet of the circulating oil pump is arranged at a position opposite to the oil suction port.

[0011] Another technical solution of the utility model is as follows: a multi-station hydraulic pump test bench, comprising: at least two test stations, a test circuit connected to each test station, and an oil temperature control system of any of the above-mentioned multi-station hydraulic pump test benches, wherein the test station is connected to a cold oil zone via an oil inlet pipeline, the oil outlet of the test circuit is arranged in a hot oil zone, and the test station is used to install a hydraulic pump to be tested.

[0012] Furthermore, the test circuit includes a high-pressure filter, a flow meter, a proportional relief valve and a return oil filter, the input end of the high-pressure filter is connected to the oil outlet of the hydraulic pump to be tested, the output end of the high-pressure filter is connected to one end of the flow meter, the other end of the flow meter is connected to one end of the proportional relief valve, the other end of the proportional relief valve is connected to one end of the return oil filter, the other end of the return oil filter is placed in the hot oil area, and a pressure sensor is arranged between the high-pressure filter and the hydraulic pump to be tested.

[0013] Beneficial effects of the utility model: the oil inlet temperature sensor of the utility model is installed in the oil pump inlet pipeline, and the oil temperature test is more accurate and close to the hydraulic pump, avoiding the measurement deviation caused by directly measuring the oil tank temperature.

[0014] The oil suction port of the oil tank cooling circuit is arranged in the hot oil area. The oil in the hot oil area is cooled and then returned to the cold oil area of ​​the oil tank, accelerating the uniformity of the overall temperature of the oil tank.

[0015] An oil tank circulation loop is arranged in the cold oil area of ​​the oil tank. The circulation loop pumps the cold oil from the lower layer of the oil tank to the upper layer in the oil suction area (cold oil area) of the pump under test, thereby accelerating the temperature uniformity of the oil tank in the oil suction area (cold oil area) of the pump under test, making the oil temperature of the pump under test at the two stations consistent, thereby avoiding the problem of suspension of hydraulic pump factory testing and low test efficiency due to the oil temperature not being within the required temperature range for the test during the two-station test.

[0016] The controller adopts PID control algorithm according to the data of the workstation temperature sensor. When the oil temperature is close to the upper and lower limits, it uses deviation detection to give a smaller opening to the water valve to avoid oil temperature overshoot and avoid poor oil temperature control effect caused by traditional switch control. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the utility model. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. The described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0019] In one technical solution of the utility model, Figure 1 The following is a schematic diagram of the specific structure of an oil temperature control system of a multi-station hydraulic pump test bench according to the technical solution. Figure 1 As shown, the utility model specifically includes:

[0020] A hydraulic oil tank 1, a controller, an oil tank cooling circuit, an oil tank circulation circuit and a workstation temperature sensor 2. The hydraulic oil tank 1 is divided into a hot oil area and a cold oil area. Specifically, in order to prevent the bubbles generated by the oil return impact of the return oil pipe of the measured pump from being directly sucked away by the oil inlet pipe of the measured pump to generate vibration and noise, an oil tank partition is set in the hydraulic oil tank 1 corresponding to the cold oil area and the hot oil area of ​​the measured pump.

[0021] The oil suction port of the oil tank cooling circuit is arranged in the hot oil area, and the oil outlet is arranged in the cold oil area. One end of the oil tank circulation circuit is arranged in the upper part of the cold oil area, and the other end is arranged in the lower part of the cold oil area. The station temperature sensor 2 is installed in the oil inlet pipeline of each test station 4, and the controller is respectively connected to the oil tank cooling circuit and each station temperature sensor 2;

[0022] The oil tank cooling circuit is used to cool the oil in the hot oil area and transport it to the cold oil area, and the oil tank circulation circuit is used to circulate and mix the oil in the upper and lower layers of the cold oil area to make the temperature of the cold oil area uniform;

[0023] The controller is used to adjust the cooling efficiency of the oil tank cooling circuit according to the data of the station temperature sensor 2, specifically using a PID control algorithm to ensure that the temperature of the oil in the oil inlet pipeline entering the test station 4 is within a preset temperature.

[0024] The oil tank cooling circuit includes: a cooling oil pump 14, a water cooler 15 and an electromagnetic proportional valve 16. The oil suction port of the cooling oil pump 14 is placed in the hot oil area, the oil outlet of the cooling oil pump 14 is connected to the oil inlet of the cooler, the oil outlet of the cooler is placed in the cold oil area, the cooling medium is introduced into the cooler, the cooling medium inlet of the cooler is connected to the electromagnetic proportional valve 16, the electromagnetic proportional valve 16 is connected to a controller, and the controller is used to adjust the opening of the electromagnetic proportional valve 16 according to the data of the station temperature sensor 2. A filter 20 is provided at the oil suction port of the cooling oil pump 14 and the oil outlet of the cooler.

[0025] The oil tank cooling circuit includes an oil suction filter 20 connected to the hot oil area of ​​the hydraulic oil tank 1, a cooling oil pump group, a water cooler 15, an oil return filter 12 and a cold oil area of ​​the hydraulic oil tank 1, which are connected in sequence. The water cooler 15 is a plate heat exchanger. The cooling oil pump group includes a cooling hydraulic pump 14 and a cold drive motor 13 connected to the cooling oil pump. The water inlet of the water cooler 15 is connected to an electromagnetic proportional valve 16, which can be an electric proportional butterfly valve. The water outlet of the water cooler 15 is connected to a cooling water tower. The controller controls the opening of the electric proportional butterfly valve through the PID algorithm and the parameters of the two temperature sensors, thereby controlling the cooling efficiency.

[0026] The oil tank circulation loop includes a circulating oil pump 18, which is connected to a circulating motor 17. The oil suction port of the circulating oil pump 18 is arranged at the upper or lower part of the cooling zone, and the oil outlet of the circulating oil pump 18 is arranged at a position opposite to the oil suction port. A circulating pump is arranged in the cold oil area of ​​the cold oil area of ​​the oil tank in the cold oil area of ​​the tested pump, and the circulating pump pumps the cold oil from the lower layer of the oil tank to the upper layer in the cold oil area of ​​the tested pump suction area, accelerates the temperature of the oil tank in the cold oil area of ​​the tested pump suction area to be uniform, so that the oil temperature of the tested pumps at the two stations is consistent, and avoids the problem of suspension of the factory test of the hydraulic pump due to the oil temperature not being within the required temperature range of the test during the two-station test, and low test efficiency.

[0027] In one technical solution of the utility model, Figure 1 This is a structural schematic diagram of a multi-station hydraulic pump test bench according to the technical solution. Figure 1 As shown, it includes: at least two test stations 4, a test circuit connected to each test station 4, and an oil temperature control system of any of the above-mentioned multi-station hydraulic pump test benches, wherein the test station 4 is connected to the cold oil area through an oil inlet pipeline, the oil outlet of the test circuit is set in the hot oil area, and the test station 4 is used to install the hydraulic pump to be tested. The oil suction ports of multiple test stations 4 are all set in the cold oil area, and the oil in the cold oil area is further cooled and mixed through the oil tank circulation circuit to ensure that the oil temperature sucked by multiple test stations 4 is within the test requirement range.

[0028] Wherein, the test circuit includes a high-pressure filter 9, a flow meter 10, a proportional relief valve 11 and a return oil filter 12, the input end of the high-pressure filter 9 is connected to the oil outlet of the hydraulic pump to be tested, the output end of the high-pressure filter 9 is connected to one end of the flow meter 10, the other end of the flow meter 10 is connected to one end of the proportional relief valve 11, the other end of the proportional relief valve 11 is connected to one end of the return oil filter 12, the other end of the return oil filter 12 is placed in the hot oil area, and a pressure sensor 8 is arranged between the high-pressure filter 9 and the hydraulic pump to be tested.

[0029] The hydraulic pump test circuit includes a pressure sensor 8, a high-pressure filter 9, a flow meter 10, a proportional relief valve 11 and a return oil filter 12, which are respectively connected to the oil outlet of the hydraulic pump under test. During the hydraulic pump test, it is necessary to adjust the electric proportional relief valve 11 to load different pressures on the hydraulic pump outlet to achieve flow testing of different pressures of the hydraulic pump. During the loading process of the hydraulic pump, the high-pressure overflow of the hydraulic pump converts the mechanical energy of the motor into heat of the hydraulic oil, and is connected to the hot oil area of ​​the hydraulic oil tank 1 through the return oil filter 12.

[0030] The hydraulic pump under test is driven to rotate by adjusting the different rotation speeds of the workstation servo motor 5, and the outlet pressure of the hydraulic pump under test is changed by giving different analog voltage signals to the proportional relief valve 11; the outlet pressure of the hydraulic pump is collected by the pressure sensor 8, and the outlet flow of the hydraulic pump is collected by the flow sensor.

[0031] Since the hydraulic pump loading will generate a lot of heat when the hydraulic pump performance test is carried out, oil temperature control is required to ensure that the oil temperature is within a certain temperature range, such as 50±4℃. Initially, the proportional relief valve 11 in the circuit of the hydraulic pump under test can be used for overflow heating. When the hydraulic pump is pressurized and overflows, the oil generates heat. After heating to the required temperature range, the temperature of the hydraulic oil tank 1 is controlled by water cooling in the oil tank cooling circuit. When the actual oil temperature of the hydraulic oil tank 1 does not reach the set oil temperature, the electric proportional butterfly valve is opened or closed with a smaller opening, so that the oil temperature is in a rising period. When the actual oil temperature reaches above the set oil temperature, the electric proportional butterfly valve is initially opened or operated with a larger opening through the PID algorithm of the temperature control system, increasing the water inlet of the water cooler 15 and accelerating the cooling of the oil temperature. When the oil temperature is close to the upper and lower limits, the water inlet of the water cooler 15 is reduced through the PID algorithm of the temperature control system, so that the oil inlet temperature of the pump under test is controlled within the specified test temperature range.

[0032] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to examples, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. An oil temperature control system for a multi-station hydraulic pump test bench, characterized in that: include: A hydraulic oil tank (1), a controller, an oil tank cooling circuit, an oil tank circulation circuit and a workstation temperature sensor (2), wherein the hydraulic oil tank (1) is divided into a hot oil area and a cold oil area, an oil suction port of the oil tank cooling circuit is arranged in the hot oil area, and an oil outlet is arranged in the cold oil area, one end of the oil tank circulation circuit is arranged at the upper part of the cold oil area, and the other end is arranged at the lower part of the cold oil area, the workstation temperature sensor (2) is installed in the oil inlet pipeline of each test station (4), and the controller is respectively connected to the oil tank cooling circuit and each workstation temperature sensor (2); The oil tank cooling circuit is used to cool the oil in the hot oil area and transport it to the cold oil area, and the oil tank circulation circuit is used to circulate and mix the oil in the upper and lower layers of the cold oil area to make the temperature of the cold oil area uniform; The controller is used to adjust the cooling efficiency of the oil tank cooling circuit according to data from the workstation temperature sensor (2) to ensure that the temperature of the oil in the oil inlet pipeline entering the test station (4) is within a preset temperature.

2. The oil temperature control system of the multi-station hydraulic pump test bench according to claim 1, characterized in that: The oil tank cooling circuit comprises: a cooling oil pump (14), a water cooler (15) and an electromagnetic proportional valve (16); the oil suction port of the cooling oil pump (14) is located in the hot oil zone; the oil outlet of the cooling oil pump (14) is connected to the oil inlet of the cooler; the oil outlet of the cooler is located in the cold oil zone; a cooling medium is introduced into the cooler; the cooling medium inlet of the cooler is connected to the electromagnetic proportional valve (16); the electromagnetic proportional valve (16) is connected to a controller; the controller is used to adjust the opening of the electromagnetic proportional valve (16) according to data of the workstation temperature sensor (2).

3. The oil temperature control system of the multi-station hydraulic pump test bench according to claim 2, characterized in that: A filter (20) is provided at the oil suction port of the cooling oil pump (14) and the oil outlet of the cooler.

4. The oil temperature control system of the multi-station hydraulic pump test bench according to claim 1, characterized in that: The oil tank circulation loop comprises a circulating oil pump (18), the oil suction port of the circulating oil pump (18) being arranged at the upper part or the lower part of the cooling zone, and the oil outlet of the circulating oil pump (18) being arranged at a position opposite to the oil suction port.

5. A multi-station hydraulic pump test bench, characterized in that: include: At least two test stations (4), a test circuit connected to each test station (4), and an oil temperature control system of a multi-station hydraulic pump test bench as described in any one of claims 1 to 4, wherein the test station (4) is connected to a cold oil zone via an oil inlet pipeline, the oil outlet of the test circuit is arranged in a hot oil zone, and the test station (4) is used to install a hydraulic pump to be tested.

6. The multi-station hydraulic pump test bench according to claim 5, characterized in that: The test circuit comprises a high-pressure filter (9), a flow meter (10), a proportional relief valve (11) and an oil return filter (12); an input end of the high-pressure filter (9) is connected to an oil outlet of a hydraulic pump to be tested; an output end of the high-pressure filter (9) is connected to one end of the flow meter (10); the other end of the flow meter (10) is connected to one end of the proportional relief valve (11); the other end of the proportional relief valve (11) is connected to one end of the oil return filter (12); the other end of the oil return filter (12) is placed in a hot oil zone; a pressure sensor (8) is provided between the high-pressure filter (9) and the hydraulic pump to be tested.

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