Tensioning hydraulic system

Abstract

The utility model relates to a tensioning hydraulic system which comprises a hydraulic oil tank, a tensioning oil cylinder and a three-position four-way electromagnetic directional valve, a P port of the three-position four-way electromagnetic directional valve is communicated with the hydraulic oil tank through a first pipeline, and a T port of the three-position four-way electromagnetic directional valve is communicated with the hydraulic oil tank through a second pipeline. A port A of the three-position four-way electromagnetic directional valve is communicated with a rodless cavity of the tensioning oil cylinder through a third pipeline, a port B of the three-position four-way electromagnetic directional valve is communicated with a rod cavity of the tensioning oil cylinder through a fourth pipeline, the first pipeline is provided with a first pump and a first one-way valve, and an outlet of the first one-way valve is communicated with the hydraulic oil tank through a fifth pipeline. The fifth pipeline is provided with a second pump and a second reversing valve, an inlet of the second reversing valve is communicated with the hydraulic oil tank through an electromagnetic overflow valve or a combination valve, and the combination valve is composed of a two-position four-way electromagnetic reversing valve and a pressure regulating valve. And the working efficiency is greatly improved under the condition that the power of the three-phase asynchronous motor is not increased.

Description

TECHNICAL FIELD

[0001] The utility model relates to prefabricated pipe pile technical field, especially a tension hydraulic system. BACKGROUND

[0002] In the pipe pile industry, a tensioning process in the factory production process of prestressed pipe piles is involved, and a commonly used method for prestressed pipe pile tensioning in the prior art is to use a three-phase asynchronous motor to drive a single superhigh-pressure constant-displacement plunger pump to generate pressure oil to push a tensioning oil cylinder to extend, thereby prestressed pipe piles are prestressed and tensioned. Since a constant-displacement radial plunger pump is used, the tensioning oil cylinder has a same speed at low pressure and high pressure, thereby the tensioning speed is limited, and the tensioning efficiency is very low. SUMMARY

[0003] In view of the deficiencies of the prior art, the utility model provides a tension hydraulic system for improving work efficiency.

[0004] To achieve the above-mentioned purpose, the utility model provides a tension hydraulic system, which has the following technical scheme: a hydraulic oil tank, a tensioning oil cylinder, a three-position four-way electromagnetic reversing valve, the P port of the three-position four-way electromagnetic reversing valve is connected with the hydraulic oil tank through a first pipeline, the T port of the three-position four-way electromagnetic reversing valve is connected with the hydraulic oil tank through a second pipeline, the A port of the three-position four-way electromagnetic reversing valve is connected with the rodless cavity of the tensioning oil cylinder through a third pipeline, the B port of the three-position four-way electromagnetic reversing valve is connected with the rod cavity of the tensioning oil cylinder through a fourth pipeline, the first pipeline is provided with a first pump and a first check valve, the first pump is located between the first check valve and the hydraulic oil tank, the outlet of the first check valve is connected with the hydraulic oil tank through a fifth pipeline, the fifth pipeline is provided with a second pump and a second reversing valve, the second pump is located between the second reversing valve and the hydraulic oil tank, the inlet of the second reversing valve is connected with the hydraulic oil tank through an electromagnetic overflow valve or a combination valve, and the combination valve is composed of a two-position four-way electromagnetic reversing valve and a pressure regulating valve.

[0005] Preferably, the P port of the two-position four-way electromagnetic reversing valve is connected with the fifth pipeline, the B port of the two-position four-way electromagnetic reversing valve is connected with the second pipeline, and the pressure regulating valve is connected with the two-position four-way electromagnetic reversing valve in parallel.

[0006] Preferably, the second pipeline and the fourth pipeline are connected through a sixth pipeline, and the sixth pipeline is provided with a first safety valve.

[0007] Preferably, the first pump is provided with a three-phase asynchronous motor or a variable frequency motor, and the first pump is a constant-displacement radial plunger pump.

[0008] Preferably, the first pipeline is provided with a second safety valve, which is located between the first pump and the first check valve.

[0009] Preferably, the first pipeline is provided with a first pressure transmitter and a system pressure gauge, which are located between the outlet of the first check valve and the outlet of the second check valve and between the P port of the three-position four-way electromagnetic reversing valve.

[0010] Preferably, the third pipeline is provided with a hydraulic control check valve, a second pressure transmitter and a tensioning oil cylinder pressure gauge.

[0011] Preferably, the hydraulic oil tank is provided with an air filter and a liquid level thermometer.

[0012] Preferably, the pipe openings of the first pipeline and the fifth pipeline are provided with oil suction filters.

[0013] The tensioning hydraulic system of the utility model provides a scheme that double pumps control the fast and slow speed of the tensioning oil cylinder through different pressures, realizes that the low-load running speed of the tensioning oil cylinder is greatly improved without increasing the power of the three-phase asynchronous motor, and greatly improves the work efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical scheme in the embodiment of the utility model, the following briefly introduces the drawings needed to be used in the embodiment.

[0015] Figure 1 It is the principle simplified view of the tensioning hydraulic system of the utility model. DETAILED DESCRIPTION

[0016] In order to more clearly describe the technical content of the utility model, the following further describes in combination with specific embodiments.

[0017] As Figure 1 As shown, it is the embodiment of the tensioning hydraulic system of the utility model. Wherein the tensioning hydraulic system includes a hydraulic oil tank 1, a tensioning oil cylinder 2, a three-position four-way electromagnetic reversing valve 5, the P port of the three-position four-way electromagnetic reversing valve 5 is communicated with the hydraulic oil tank 1 through a first pipeline 6, the T port of the three-position four-way electromagnetic reversing valve 5 is communicated with the hydraulic oil tank 1 through a second pipeline 7, the A port of the three-position four-way electromagnetic reversing valve 5 is communicated with the rodless cavity 3 of the tensioning oil cylinder 2 through a third pipeline 8, and the B port of the three-position four-way electromagnetic reversing valve 5 is communicated with the rod cavity 4 of the tensioning oil cylinder 2 through a fourth pipeline 9.

[0018] The first pipeline 6 is provided with a first pump 10 and a first check valve 12, the first pump 10 is located between the first check valve 12 and the hydraulic oil tank 1, the outlet of the first check valve 12 is communicated with the hydraulic oil tank 1 through a fifth pipeline 26, the fifth pipeline 26 is provided with a second pump 11 and a second reversing valve 13, the second pump 11 is located between the second reversing valve 13 and the hydraulic oil tank 1, the inlet of the second reversing valve 13 is communicated with the hydraulic oil tank 1 through a combination valve, and the combination valve is composed of a two-position four-way electromagnetic reversing valve 16 and a pressure regulating valve 15. On the one hand, the high-pressure and low-pressure double-pump combined control is used to control the fast and slow operation of the tensioning oil cylinder, so that the efficiency is improved; on the other hand, through the combination control of the electromagnetic reversing valve and the pressure regulating valve, the second pump is used as a low-pressure pump to unload when the pressure reaches the set pressure, so that the power of the three-phase asynchronous motor is not overloaded when the hydraulic system is under high pressure, and the motor power is effectively used to the maximum extent. The combination valve can also be replaced by an electromagnetic overflow valve.

[0019] Specifically, the P port of the two-position four-way electromagnetic reversing valve 16 is communicated with the fifth pipeline 26, the B port of the two-position four-way electromagnetic reversing valve 16 is communicated with the second pipeline 7, and the pressure regulating valve 15 is connected in parallel with the two-position four-way electromagnetic reversing valve 16.

[0020] The second pipeline 7 and the fourth pipeline 9 are communicated through a sixth pipeline 27, and the sixth pipeline 27 is provided with a first safety valve 28.

[0021] The first pump 10 is provided with a three-phase asynchronous motor 17, and the first pump 10 is a constant-displacement radial piston pump. The three-phase asynchronous motor can also be replaced by a variable frequency motor to realize variable flow control of the output pressure oil.

[0022] The first pipeline 6 is provided with a second safety valve 14, and the second safety valve 14 is located between the first pump 10 and the first check valve 12.

[0023] The first pipeline 6 is also provided with a first pressure transmitter 21 and a system pressure gauge 22, and the first pressure transmitter 21 and the system pressure gauge 22 are located between the communication between the outlet of the first check valve 12 and the outlet of the second check valve 13 and the P port of the three-position four-way electromagnetic reversing valve 5.

[0024] The third pipeline 8 is provided with a hydraulic control check valve 25, a second pressure transmitter 24 and a tensioning oil cylinder pressure gauge 23.

[0025] The hydraulic oil tank 1 is provided with an air filter 18 and a liquid level thermometer 19.

[0026] The pipe openings of the first pipeline and the fifth pipeline are all provided with oil suction filters 20.

[0027] The tension hydraulic system can be used under the normal operation of the three-phase asynchronous motor.

[0028] The tension hydraulic system can be used under the normal operation of the three-phase asynchronous motor.

[0029] When the tension cylinder 2 is subjected to a large external load, the combined pressure of the double pumps reaches the low pressure set by the first pressure transmitter 21, the first pressure transmitter 21 sends a signal to control the electromagnetic iron YV2 of the two-way electromagnetic reversing valve 16 to lose power, at this time, the pressure oil pumped out by the low-pressure pump flows into the B port of the two-way electromagnetic reversing valve 16 through the P port, and then is injected into the hydraulic oil tank 1, thereby realizing unloading of the low-pressure pump, at this time, only the quantitative radial piston pump supplies oil to the rodless cavity 3 of the tension cylinder 2, at this time, the load increases, and the tension cylinder is slowly extended under heavy load.

[0030] When the pressure oil flowing into the tension cylinder rodless cavity reaches the set pressure of the second pressure transmitter 24 and the process requirement, the electromagnetic iron YV1b of the three-way electromagnetic reversing valve 5 and the electromagnetic iron YV2 of the two-way electromagnetic reversing valve 16 are powered at the same time, the combined pressure oil is injected into the tension cylinder rod cavity 4 through the P and B ports of the three-way electromagnetic reversing valve 5, and the pressure oil pushes the piston rod to retract quickly.

[0031] When the tension work is suspended, the electromagnetic iron of the three-way electromagnetic reversing valve 5 and the electromagnetic iron YV1a, YV1b and YV2 of the two-way electromagnetic reversing valve 16 are not powered at the same time, at this time, the pressure oil of the two oil pumps flows back to the hydraulic oil tank 1 through the neutral position of the three-way electromagnetic reversing valve 5 and the P and B ports of the two-way electromagnetic reversing valve 16, thereby realizing the unloading function of the hydraulic system.

[0032] The tension hydraulic system provides a scheme for controlling the fast and slow speed of the tension cylinder by different pressures of the double pumps, realizes that the low-load operation speed of the tension cylinder is greatly improved without increasing the power of the three-phase asynchronous motor, and greatly improves the work efficiency.

[0033] In this specification, the present application has been described with reference to specific embodiments thereof. It is, however, apparent that various modifications and changes can be made thereto without departing from the spirit and scope of the present application. Therefore, the specification and drawings should be considered in an illustrative, and not a restrictive, sense.

Claims

1. A tensioning hydraulic system, characterized in that, The hydraulic oil tank, the tensioning oil cylinder, the three-position four-way electromagnetic reversing valve, the P port of the three-position four-way electromagnetic reversing valve is communicated with the hydraulic oil tank through the first pipeline, the T port of the three-position four-way electromagnetic reversing valve is communicated with the hydraulic oil tank through the second pipeline, the A port of the three-position four-way electromagnetic reversing valve is communicated with the rodless cavity of the tensioning oil cylinder through the third pipeline, the B port of the three-position four-way electromagnetic reversing valve is communicated with the rod cavity of the tensioning oil cylinder through the fourth pipeline, the first pipeline is provided with a first pump and a first check valve, the first pump is located between the first check valve and the hydraulic oil tank, the outlet of the first check valve is communicated with the hydraulic oil tank through the fifth pipeline, the fifth pipeline is provided with a second pump and a second reversing valve, the second pump is located between the second reversing valve and the hydraulic oil tank, the inlet of the second reversing valve is communicated with the hydraulic oil tank through an electromagnetic overflow valve or a combination valve, and the combination valve is composed of a two-position four-way electromagnetic reversing valve and a pressure regulating valve.

2. The tension hydraulic system of claim 1, wherein, The P port of the two-position four-way electromagnetic reversing valve is communicated with the fifth pipeline, the B port of the two-position four-way electromagnetic reversing valve is communicated with the second pipeline, and the pressure regulating valve is connected in parallel with the two-position four-way electromagnetic reversing valve.

3. The tension hydraulic system of claim 1, wherein, The second pipeline and the fourth pipeline are communicated through the sixth pipeline, and the sixth pipeline is provided with a first safety valve.

4. The tension hydraulic system of claim 1, wherein, The first pump is provided with a three-phase asynchronous motor or a variable frequency motor, and the first pump is a constant displacement radial piston pump.

5. The tension hydraulic system of claim 1, wherein, The first pipeline is provided with a second safety valve, and the second safety valve is located between the first pump and the first check valve.

6. The tension hydraulic system of claim 1, wherein, The first pipeline is provided with a first pressure transmitter and a system pressure gauge, and the first pressure transmitter and the system pressure gauge are located between the outlet of the first check valve and the outlet of the second check valve and the P port of the three-position four-way electromagnetic reversing valve.

7. The tension hydraulic system of claim 1, wherein, The third pipeline is provided with a hydraulic control check valve, a second pressure transmitter and a tensioning oil cylinder pressure gauge.

8. The tension hydraulic system of claim 1, wherein, The hydraulic oil tank is provided with an air filter and a liquid level thermometer.

9. The tension hydraulic system of claim 1, wherein, The pipe openings of the first pipeline and the fifth pipeline are all provided with oil suction filters.

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