Adjustable constant-pressure variable hydraulic system

Abstract

The utility model belongs to the technical field of hydraulic control systems, and particularly relates to an adjustable constant-pressure variable hydraulic system which is characterized by comprising a constant-pressure hydraulic pump, a safety valve, a one-way valve, a high-pressure filter, an oil tank and a pressure gauge. A constant-pressure hydraulic pump, a one-way valve and a high-pressure filter are sequentially arranged on the output oil way, a safety valve is arranged on a pipeline between the constant-pressure hydraulic pump and the one-way valve, an outlet of the safety valve is communicated with the oil tank, and a pressure collecting pipe is connected between the high-pressure filter and the one-way valve; and an oil return filter is arranged on the oil return path. Compared with the prior art, the utility model has the beneficial effects that a cooperative adjustment structure is adopted, the structure is simple, the adjustment key points are clear, system faults caused by improper adjustment of hydraulic pressure values can be obviously reduced, the maintenance cost and the maintenance intensity are reduced, fault judgment is simplified, and shutdown of equipment caused by a hydraulic system is reduced; the labor productivity is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of hydraulic control systems, and in particular relates to an adjustable constant-pressure variable hydraulic system. Background Art

[0002] Hydraulic control systems are increasingly used in the metallurgical industry. Hydraulic pumps serve as a power source, and together with hydraulic valves, hydraulic cylinders and hydraulic media, form a hydraulic transmission mechanism. The hydraulic transmission mechanism is stable and reliable in operation, suitable for work environments with harsh operating environments and narrow operating spaces. It has high control accuracy, is easy to maintain, and can meet the requirements of different forms of production conditions. It is widely used in actual production.

[0003] In the production process of ductile iron pipes, a large number of hydraulic transmission mechanisms are used to complete the production of each production process and the connection between processes. It is also one of the preferred transmission methods for lean control and the development of unmanned operation. There are many ways to control the pressure of hydraulic systems, such as pressure limiting, unloading, constant pressure, etc. In the hydraulic system, the same specification and model of pressure control valves play different roles in different hydraulic control systems. Some systems are called safety valves for safety, some systems are called overflow valves for overflow, and some are called unloading valves for unloading. In the hydraulic system, the pressure setting is based on the function of the control system to set the pressure value. Improper pressure setting or improper adjustment method will affect the operation of the hydraulic system and the production process. In the case of light, the oil tank will heat up, and in the case of heavy, the production will be affected and the production rhythm will be hindered. Therefore, in the hydraulic system, the adjustment of pressure is the core concern. The technicians responsible for the adjustment have different abilities and understandings. Deviations are prone to occur during pressure adjustment. The size of the deviation will have a certain impact on the life of the hydraulic system. In severe cases, failures are prone to occur and production will be stopped.

[0004] The Chinese utility model patent with application number 202020861994.7 discloses a closed electro-hydraulic control system for a hydraulic motor driven press, which mainly includes: an electro-hydraulic proportional variable hydraulic motor, an electro-hydraulic proportional variable pump, an oil replenishment pump, an oil replenishment pressure regulating valve, a hovering solenoid valve, a hovering safety valve, a pressing safety valve, a first oil replenishment check valve, a second oil replenishment check valve, a first electromagnetic ball valve, a second electromagnetic ball valve, a balanced safety valve, a balanced accumulator group, a first pressure sensor, a second pressure sensor, a third pressure sensor, a motor, etc. This solution can realize automatic stepless adjustment of parameters such as pressing force and pressing speed, but the disadvantage is that the structure is complex and prone to failure. Utility Model Content

[0005] The purpose of the utility model is to provide an adjustable constant-pressure variable hydraulic system, which overcomes the shortcomings of the prior art, adopts the coordinated adjustment of the hydraulic system pressure, and ensures the stable operation of the hydraulic system and the orderly and smooth operation on site by regulating the hydraulic system pressure. It can significantly reduce system failures caused by improper adjustment of hydraulic pressure values, reduce maintenance costs and maintenance intensity, simplify fault judgment, reduce equipment downtime caused by hydraulic system reasons, and improve labor productivity.

[0006] To achieve the above purpose, the utility model is implemented through the following technical solutions:

[0007] An adjustable constant-pressure variable hydraulic system, characterized in that it includes a constant-pressure hydraulic pump, a safety valve, a one-way valve, a high-pressure filter, an oil tank and a pressure gauge, the oil tank being respectively connected to an output oil circuit and an oil return oil circuit, the output oil circuit being sequentially provided with a constant-pressure hydraulic pump, a one-way valve and a high-pressure filter, the pipeline between the constant-pressure hydraulic pump and the one-way valve being provided with a safety valve, the outlet of the safety valve being connected to the oil tank, a pressure collection pipe being connected between the high-pressure filter and the one-way valve; the return oil circuit being sequentially provided with a cooler and an oil return filter, the outlet of the oil return filter being connected to the oil tank.

[0008] One end of the pressure collection tube is connected to a pressure relay, and the other end is connected to a seismic-resistant pressure gauge.

[0009] The model of the constant pressure hydraulic pump is A10VSO45DR, and the matching motor is Y2-180-4-22KW.

[0010] The specification of the safety valve is DBW20B-30 / 31.5AG24NZ5L, and the specification of the one-way valve is RVP20-10.

[0011] The oil inlet of the seismic-resistant pressure gauge is connected with a pressure measuring point.

[0012] The specification of the seismic-resistant pressure gauge is Y-60ZT (16MPa).

[0013] The specification of the pressure relay is HED80H10 / 200L24.

[0014] The specification of the return oil filter is RFA250-10FY.

[0015] The safety valve in the hydraulic system of the utility model only plays the role of a safety valve; the one-way valve controls the oil to flow in only one direction to prevent the oil from flowing back and causing harm to the hydraulic pump; the high-pressure filter filters the pressure oil with precision to ensure that the hydraulic oil slides flexibly when passing through the control valve and prevents the oil impurities from causing blockage to the control valve and forming a hydraulic fault.

[0016] Compared with the prior art, the beneficial effects of the utility model are:

[0017] 1) The coordinated adjustment structure is simple and makes the adjustment points clear, which is conducive to standardizing the adjustment of the hydraulic system pressure, ensuring the stable operation of the hydraulic system and the order and smoothness of the site, significantly reducing the system failures caused by improper adjustment of the hydraulic pressure value, reducing maintenance costs and maintenance intensity, simplifying fault diagnosis, reducing equipment downtime due to hydraulic system problems, and improving labor productivity.

[0018] 2) After the system pressure is set, it can automatically change the variable according to the on-site working conditions. When working, the variable mechanism reaches the maximum and outputs a larger flow rate. When the site does not need to work, the variable mechanism adjusts the output of a smaller flow rate through the variable head, close to zero output. In this way, the pump outputs a larger energy when working and a smaller energy when not working, which is energy-saving and environmentally friendly, avoiding energy loss and preventing the phenomenon of oil tank heating. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the principle structure of an embodiment of the utility model;

[0020] Figure 2 It is a schematic diagram of the external structure of an embodiment of the utility model;

[0021] Figure 3 yes Figure 2 Top view of the .

[0022] In the figure: 1-liquid level gauge, 2-constant pressure hydraulic pump, 3-air filter, 4-liquid level alarm, 5-temperature controller, 6-return oil filter, 7-cooler, 8-safety valve, 9-check valve, 10-high pressure filter, 11-pressure relay, 12-seismic pressure gauge, 13-pressure regulating knob, 14-oil tank, 15-pressure collection pipe. DETAILED DESCRIPTION

[0023] The technical solution of the present utility model will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present utility model, rather than all of the embodiments.

[0024] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the specific embodiments required to be used in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the specific embodiments described below are some implementation methods of the utility model. For ordinary technicians in this field, other specific embodiments can be obtained based on these specific embodiments without paying creative work.

[0025] The components of the embodiments of the present invention generally described and shown in the specific embodiments herein can be arranged and designed in countless different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the specific embodiments is not intended to limit the scope of the utility model claimed, but only represents the selected embodiments of the utility model.

[0026] See Figure 1-3 , is a schematic diagram of the structure of an adjustable constant pressure variable hydraulic system embodiment of the utility model, including a constant pressure hydraulic pump 2, a safety valve 8, a one-way valve 9, a high pressure filter 10 and an oil tank 14, on which a liquid level gauge 1, an air filter 3, a liquid level alarm 4 and a temperature controller 5 are respectively provided. The oil tank 14 is also connected to the output oil circuit and the return oil circuit respectively, and the output oil circuit is provided with a constant pressure hydraulic pump 2, a one-way valve 9 and a high pressure filter 10 in sequence, and the pipeline between the constant pressure hydraulic pump 2 and the one-way valve 9 is provided with a safety valve 8, the outlet of the safety valve 8 is connected to the oil tank 14, and a pressure collection pipe 15 is connected between the high pressure filter 10 and the one-way valve 9; the return oil circuit is provided with a cooler 7 and a return oil filter 6 in sequence, and the outlet of the return oil filter 6 is connected to the oil tank.

[0027] One end of the pressure collection tube 15 is connected to the pressure relay 11, and the other end is connected to the seismic pressure gauge 12. In the embodiment, the model of the constant pressure hydraulic pump 2 is A10VSO45DR, and the matching motor is Y2-180-4-22KW. The pump belongs to a constant pressure variable pump with a rated pressure of 31.5MPa. This series of pumps has its own variable mechanism, that is, the pressure regulating knob 13.

[0028] The specification of the safety valve 8 is DBW20B-30 / 31.5AG24NZ5L, and the specification of the check valve 9 is RVP20-10. The oil inlet of the seismic pressure gauge 12 is connected to a pressure measuring point. The specification of the seismic pressure gauge is Y-60ZT (16MPa). The specification of the pressure relay 11 is HED80H10 / 200L24. The specification of the return oil filter 6 is RFA250-10FY.

[0029] The pressure adjustment steps of the constant pressure variable hydraulic system of the utility model are as follows:

[0030] Taking the hydraulic system set pressure as 10MPa as an example, before starting the new constant pressure hydraulic pump 2, fill the hydraulic oil into the oil filling port of the constant pressure hydraulic pump 2 pump housing, close the filling port after the air in the housing is exhausted, adjust the pressure regulating knob 13 of the pump head, and turn the pressure regulating knob 13 out to close to 0-2MPa. Turning it in increases the pressure, and turning it out decreases the pressure. At this time, after the constant pressure hydraulic pump 2 runs without load for 30 to 50 minutes, check the shell temperature (the temperature should be lower than 60℃) and the abnormal sound during the operation of the constant pressure hydraulic pump. After meeting the above requirements, adjust the pump head pressure regulating knob 13, adjust the pump output pressure to more than 12MPa, and take the value displayed on the pressure gauge as the standard. At this time, the safety valve 8 on the hydraulic system pre-adjusts the pressure to more than 12MP, and then adjusts the safety valve 8 knob to reduce the pressure to 12MP, and locks the safety valve 8 knob cap; then readjust the pump head pressure regulating knob 13, reduce the pressure to 10MPa, test the machine, and observe whether the pressure changes. If there is no change, lock the spare cap on the pump head pressure regulating knob 13 to complete the adjustment of the system pressure. After the pump pressure is adjusted, it is also the working pressure of the hydraulic system.

[0031] The pressure setting of the safety valve 8 is 1.2 times the system pressure, which can avoid the safety valve pressure being set too low or too high, affecting the stability of the entire hydraulic system. If the pressure is set too low, the safety valve will not work and become a relief valve, and the oil temperature in the oil tank will rise rapidly, affecting the system operation. If the pressure is set too high, the constant pressure hydraulic pump cannot release the pressure in time when overpressure occurs, which may cause pressure breakdown in the weak link of the hydraulic system and cause failure.

[0032] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An adjustable constant pressure variable hydraulic system, characterized in that: It includes a constant pressure hydraulic pump, a safety valve, a one-way valve, a high-pressure filter, an oil tank and a pressure gauge. The oil tank is respectively connected to an output oil circuit and an oil return oil circuit. The output oil circuit is sequentially provided with a constant pressure hydraulic pump, a one-way valve and a high-pressure filter. A safety valve is provided on the pipeline between the constant pressure hydraulic pump and the one-way valve. The outlet of the safety valve is connected to the oil tank. A pressure collection pipe is connected between the high-pressure filter and the one-way valve. A cooler and an oil return filter are sequentially provided on the oil return oil circuit. The outlet of the oil return filter is connected to the oil tank.

2. The adjustable constant pressure variable hydraulic system according to claim 1, characterized in that: One end of the pressure collection tube is connected to a pressure relay, and the other end is connected to a seismic-resistant pressure gauge.

3. The adjustable constant pressure variable hydraulic system according to claim 1, characterized in that: The model of the constant pressure hydraulic pump is A10VSO45DR, and the matching motor is Y2-180-4-22KW.

4. The adjustable constant pressure variable hydraulic system according to claim 1, characterized in that: The specification of the safety valve is DBW20B-30 / 31.5AG24NZ5L, and the specification of the one-way valve is RVP20-10.

5. The adjustable constant pressure variable hydraulic system according to claim 2, characterized in that: The oil inlet connection of the seismic-resistant pressure gauge is provided with a pressure measuring point.

6. The adjustable constant pressure variable hydraulic system according to claim 2, characterized in that: The specification of the seismic-resistant pressure gauge is Y-60ZT (16MPa).

7. The adjustable constant pressure variable hydraulic system according to claim 2, characterized in that: The specification of the pressure relay is HED80H10 / 200L24.

8. The adjustable constant pressure variable hydraulic system according to claim 1, characterized in that: The specification of the return oil filter is RFA250-10FY.

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