Hydraulic system for pipe fitting pressure testing machine

Abstract

The utility model provides a hydraulic system for a pipe fitting pressure testing machine, and relates to the technical field of hydraulic systems, the hydraulic system comprises a main oil supply device, a hydraulic control valve group, an execution assembly and an auxiliary oil supply device, the main oil supply device comprises a main oil tank, a first hydraulic pump and a second hydraulic pump; the hydraulic control valve group comprises a first electro-hydraulic directional control valve, a first hydraulic control one-way valve, a two-position two-way electromagnetic valve, a second electro-hydraulic directional control valve, a second hydraulic control one-way valve, a servo proportional valve, a third hydraulic control one-way valve and a third two-position four-way electromagnetic valve; the execution assembly comprises a water pressure cylinder, a main sealing pressing cylinder and two auxiliary hydraulic cylinders. The auxiliary oil supply device comprises an auxiliary oil tank and a prefill valve. The water pressure boosting cylinder is connected with a first pressure sensor, the main sealing pressing cylinder is connected with a second pressure sensor, and the first pressure sensor and the second pressure sensor are in communication feedback control connection with the servo proportional valve. Water pressure and sealing pressure data are collected in real time, and closed-loop control and dynamic balance of pressure are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic systems, in particular to a hydraulic system for a pipe pressure testing machine. Background Art

[0002] The pipe pressure tester is a device used to test whether the pressure resistance of seamless steel pipes and welded steel pipes reaches the required level. The hydraulic system of the pipe pressure tester is used to control the pipe end sealing, pipe internal pressurization and other auxiliary functions. At present, the pipe end sealing mostly adopts the form of end face sealing to ensure that the entire range of the tested pipe can withstand high pressure testing, but this sealing form has high requirements on the dynamic matching of sealing pressure and water pressure. If the sealing pressure is too high, it will damage the tested pipe, and if the sealing pressure is too low, the seal will be unreliable. Utility Model Content

[0003] The utility model aims to provide a hydraulic system for a pipe pressure testing machine. The sealing hydraulic cylinder adopts high-frequency response servo control, collects water pressure and sealing pressure data in real time, realizes closed-loop control and dynamic balance of pressure, and achieves optimal parameter matching.

[0004] The above technical objectives of the utility model are achieved through the following technical solutions:

[0005] A hydraulic system for a pipe pressure testing machine comprises a main oil supply device, a hydraulic control valve group, an actuator and an auxiliary oil supply device, wherein the main oil supply device is connected to the actuator through the hydraulic control valve group, and the auxiliary oil supply device is connected to the actuator;

[0006] The main oil supply device includes a main oil tank, a first hydraulic pump, a second hydraulic pump and oil ports UP, VP, UT and VT. The oil ports UT and VT are in communication with the main oil tank. The input oil ports of the first hydraulic pump and the second hydraulic pump are in communication with the main oil tank. The first hydraulic pump is connected to a first motor, and the second hydraulic pump is connected to a second motor. The output oil port of the first hydraulic pump is in communication with the oil port UP and a first one-way valve is provided therebetween. The output oil port of the second hydraulic pump is in communication with the oil port VP and a second one-way valve is provided therebetween.

[0007] The hydraulic control valve group includes a first electro-hydraulic reversing valve, a first hydraulically controlled one-way valve, a two-position two-way solenoid valve, oil ports XP, YP, XT, EF, EG, GF, GG, and GH. The oil ports XP, YP, and XT are connected to the oil ports UP, VP, and UT of the main oil supply device respectively in one-to-one correspondence;

[0008] The first electro-hydraulic directional control valve includes oil ports EP, ET, EA, EB and electromagnets YVEA and YVEB, the first hydraulically controlled one-way valve includes oil ports EC, ED, EX, and the two-position two-way solenoid valve includes oil ports FA, FP and electromagnet YVFA;

[0009] The oil port EP of the first electro-hydraulic reversing valve is connected to the oil port XP, the oil port ET is connected to the oil port XT, the oil port EA is connected to the oil port EC of the first hydraulically controlled one-way valve, and the oil port EB is connected to the oil port EG and the oil port EX of the first hydraulically controlled one-way valve; the oil port ED of the first hydraulically controlled one-way valve and the oil port FP of the two-position two-way solenoid valve are connected to the oil port EF respectively, and the oil port FA of the two-position two-way solenoid valve is connected to the oil port XT;

[0010] The hydraulic control valve group further includes a second electro-hydraulic reversing valve and a second hydraulically controlled one-way valve, wherein the second electro-hydraulic reversing valve includes oil ports GP, GT, GA, GB and electromagnets YVGA, YVGB, and the second hydraulically controlled one-way valve includes oil ports GC, GD, GX;

[0011] The oil port GP of the second electro-hydraulic reversing valve is connected to the oil port YP, the oil port GT is connected to the oil port XT, the oil port GA is connected to the oil port GF and the oil port GX of the second hydraulically controlled one-way valve respectively, the oil port GB is connected to the oil port GC of the second hydraulically controlled one-way valve, and the oil port GD of the second hydraulically controlled one-way valve is connected to the oil port GG;

[0012] The hydraulic control valve group also includes a servo proportional valve, a third hydraulically controlled one-way valve and a third two-position four-way solenoid valve, wherein the servo proportional valve includes oil ports HP, HT, HA, HB and a proportional solenoid YVHA, the third hydraulically controlled one-way valve includes oil ports HC, HD, HX, and the third two-position four-way solenoid valve includes oil ports JP, JT, JA, JB and an electromagnet YVJA;

[0013] The oil port HP of the servo proportional valve is connected with the oil port YP, the oil port HT is connected with the oil port XT, the oil port HA is connected with the oil port HC of the third hydraulically controlled one-way valve, the oil port HB is blocked, and the oil port HD of the third hydraulically controlled one-way valve is connected with the oil port GH; the oil port JP of the third two-position four-way solenoid valve is connected with the oil port YP, the oil port JT is connected with the oil port XT, the oil port JA is blocked, and the oil port JB is connected with the oil port HX of the third hydraulically controlled one-way valve;

[0014] The actuator assembly includes a water pressure booster cylinder, a main seal pressing cylinder and two auxiliary hydraulic cylinders symmetrically arranged on both sides of the main seal pressing cylinder, the piston rod of the main seal pressing cylinder is fixedly connected to the piston rods of the two auxiliary hydraulic cylinders; the rod chambers of the two auxiliary hydraulic cylinders are communicated with each other and are communicated with the oil port GF of the hydraulic control valve group, and the rodless chambers are communicated with the oil port GG of the hydraulic control valve group;

[0015] The water pressure booster cylinder includes an oil port MA connected to its rodless cavity, an oil port MB connected to its rod cavity, a water inlet MC and a pressurized water output port MD, and the oil port MA is connected to the oil port EF of the hydraulic control valve group, the oil port MB is connected to the oil port EG of the hydraulic control valve group, and the pressurized water output port MD is connected to the inner cavity of the tested pipe and is connected to a first pressure sensor;

[0016] The oil port of the main sealing clamping cylinder is connected to the oil port GH of the hydraulic control valve group, and is connected to a second pressure sensor. The first pressure sensor and the second pressure sensor are connected to the proportional solenoid YVHA of the servo proportional valve for communication feedback control;

[0017] The auxiliary oil supply device includes an auxiliary oil tank and a filling valve, and the high-position oil port ST of the auxiliary oil tank is connected to the oil port VT of the main oil tank; the filling valve includes oil ports SA, SB, and SX, and the oil port SA is connected to the bottom of the auxiliary oil tank, the oil port SB is connected to the oil port of the main sealing clamping cylinder, and the oil port SX is connected to the rod chambers of the two auxiliary hydraulic cylinders and the oil port GF of the hydraulic control valve group.

[0018] Furthermore, the main oil supply device also includes a first overflow valve and a first two-position four-way solenoid valve, the first overflow valve includes oil ports CP, CT, and CX, the first two-position four-way solenoid valve includes oil ports AP, AT, AA, AB and electromagnet YVAA; the oil port CP of the first overflow valve is connected to the output oil port of the first hydraulic pump, the oil port CT is connected to the main oil tank, and the oil port CX is connected to the oil port AP of the first two-position four-way solenoid valve; the oil port AT and the oil port AA of the first two-position four-way solenoid valve are both connected to the main oil tank, and the oil port AB is blocked.

[0019] Furthermore, the main oil supply device also includes a second overflow valve and a second two-position four-way solenoid valve, the second overflow valve includes oil ports DP, DT, and DX, the second two-position four-way solenoid valve includes oil ports BP, BT, BA, BB and electromagnet YVBA; the oil port DP of the second overflow valve is connected to the output oil port of the second hydraulic pump, the oil port DT is connected to the main oil tank, and the oil port DX is connected to the oil port BP of the second two-position four-way solenoid valve; the oil port BT and the oil port BA of the second two-position four-way solenoid valve are both connected to the main oil tank, and the oil port BB is blocked.

[0020] Furthermore, a first throttle valve is provided between the oil port FA of the two-position two-way solenoid valve and the oil port XT of the hydraulic control valve group.

[0021] Furthermore, a first pressure reducing valve is provided between the oil port GP of the second electro-hydraulic reversing valve and the oil port YP of the hydraulic control valve group, and the first pressure reducing valve includes an oil port GJ and an oil port GK, and the oil port GK is connected to the oil port GP of the second electro-hydraulic reversing valve, and the oil port GJ is connected to the oil port YP of the hydraulic control valve group.

[0022] Furthermore, a second throttle valve is provided between the oil port JP of the third two-position four-way solenoid valve and the oil port YP of the hydraulic control valve group.

[0023] Furthermore, a second pressure reducing valve is provided between the oil port JP of the third two-position four-way solenoid valve and the second throttle valve, and the second pressure reducing valve includes an oil port JC and an oil port JD, and the oil port JC is connected to the second throttle valve, and the oil port JD is connected to the oil port JP of the third two-position four-way solenoid valve.

[0024] In summary, the utility model has the following beneficial effects:

[0025] 1. The utility model optimizes the hydraulic system by setting a main oil supply device, a hydraulic control valve group, an actuator, an auxiliary oil supply device, etc., and realizes the pipe end seal pre-clamping, water filling, water pressure boosting, seal clamping pressure balance, pressure maintenance, pressure reduction, pressure maintenance, pressure relief, reset, etc. of the tested pipe fittings in sequence through the switching of the hydraulic control valve group, completes the water pressure test of the pipe fittings, and ensures the sealing and safety during the test process;

[0026] 2. The utility model connects the first pressure sensor to the boost water output port MD of the hydraulic booster cylinder, connects the second pressure sensor to the oil port of the main seal pressing cylinder, and the first pressure sensor and the second pressure sensor are connected to the servo proportional valve for communication feedback control. The first pressure sensor and the second pressure sensor respectively collect water pressure and sealing pressure data in real time, and the high-frequency response servo controls the main seal pressing cylinder and the auxiliary hydraulic cylinder to achieve closed-loop control and dynamic balance of pressure, thereby achieving optimal parameter matching;

[0027] 3. The utility model can realize the rapid movement of the main seal clamping cylinder during the idle stroke by arranging the main seal clamping cylinder, the auxiliary hydraulic cylinder and the auxiliary oil supply device combination, thereby reducing the displacement of the second hydraulic pump and the driving power. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The utility model is a schematic diagram of a hydraulic system for a pipe pressure testing machine.

[0029] In the figure, 01, main oil supply device; 02, hydraulic control valve group; 03, actuator; 04, auxiliary oil supply device; 1, main oil tank; 2, first hydraulic pump; 3, first motor; 4, first relief valve; 5, first two-position four-way solenoid valve; 6, first check valve; 7, second hydraulic pump; 8, second motor; 9, second relief valve; 10, second two-position four-way solenoid valve; 11, second check valve; 12, first electro-hydraulic reversing valve; 13, first hydraulic control check valve; 14, second 1. two-position two-way solenoid valve; 2. first throttle valve; 3. first pressure reducing valve; 4. second electro-hydraulic reversing valve; 5. second hydraulically controlled one-way valve; 6. second servo proportional valve; 7. third hydraulically controlled one-way valve; 8. second throttle valve; 9. second pressure reducing valve; 10. third two-position four-way solenoid valve; 11. hydraulic booster cylinder; 12. first pressure sensor; 13. main sealing clamping cylinder; 14. auxiliary hydraulic cylinder; 15. second pressure sensor; 16. auxiliary oil tank; 17. filling valve. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] A hydraulic system for a pipe pressure testing machine, such as Figure 1 As shown, it includes a main oil supply device 01, a hydraulic control valve group 02, an actuator 03 and an auxiliary oil supply device 04. The main oil supply device 01 is connected to the actuator 03 through the hydraulic control valve group 02, and the auxiliary oil supply device 04 is connected to the actuator 03. The hydraulic control valve group 02 is used to switch the oil circuits between the main oil supply device 01 and the auxiliary oil supply device 04 and the actuator 03 to drive the actuator 03 to perform corresponding actions. Among them, the control of the entire hydraulic system is controlled by a controller to control the automatic operation and linkage of each component. This is a prior art and will not be described in detail. The controller is not shown in the figure either.

[0032] The specific structures of the main oil supply device 01, the hydraulic control valve group 02, the actuator 03 and the auxiliary oil supply device 04 are described in detail below.

[0033] like Figure 1 As shown, the main oil supply device 01 includes a main oil tank 1, a first hydraulic pump 2, a first motor 3, a first overflow valve 4, a first two-position four-way solenoid valve 5, a first non-return valve 6, a second hydraulic pump 7, a second motor 8, a second overflow valve 9, a second two-position four-way solenoid valve 10, a second non-return valve 11 and oil ports UP, VP, UT, and VT, wherein the oil ports UT and VT are connected to the main oil tank 1.

[0034] like Figure 1As shown, the first motor 3 is connected to the first hydraulic pump 2, the input oil port of the first hydraulic pump 2 is connected to the main oil tank 1, and the output oil port of the first hydraulic pump 2 is connected to the oil port UP through the first non-return valve 6. The first relief valve 4 is used to adjust the maximum output pressure of the first hydraulic pump 2, including oil ports CP, CT, and CX. The first two-position four-way solenoid valve 5 includes oil ports AP, AT, AA, AB and electromagnet YVAA. Among them, the oil port CP of the first relief valve 4 is connected to the output oil port of the first hydraulic pump 2, the oil port CT is connected to the main oil tank 1, and the oil port CX is connected to the oil port AP of the first two-position four-way solenoid valve 5; the oil ports AT and AA of the first two-position four-way solenoid valve 5 are both connected to the main oil tank 1, and the oil port AB is blocked.

[0035] like Figure 1 As shown, when the electromagnet YVAA of the first two-position four-way solenoid valve 5 loses power, its oil port AP is connected to the oil port AA, the oil port AB is connected to the oil port AT, the oil port CX of the first relief valve 4 is connected to the main oil tank 1 through the oil port AP and the oil port AA of the first two-position four-way solenoid valve 5, and the first relief valve 4 is in a load-unloading state. On the contrary, when the electromagnet YVAA of the first two-position four-way solenoid valve 5 is energized, its oil port AP is connected to the oil port AB, the oil port AA is connected to the oil port AT, the oil port CX of the first relief valve 4 is blocked after passing through the oil port AP and the oil port AB of the first two-position four-way solenoid valve 5, and the first relief valve 4 is in a pressure-building state.

[0036] like Figure 1 As shown, the second motor 8 is connected to the second hydraulic pump 7, the input oil port of the second hydraulic pump 7 is connected to the main oil tank 1, and the output oil port of the second hydraulic pump 7 is connected to the oil port VP through the second one-way valve 11. The second relief valve 9 is used to adjust the maximum output pressure of the second hydraulic pump 7, including oil ports DP, DT, and DX. The second two-position four-way solenoid valve 10 includes oil ports BP, BT, BA, BB and electromagnet YVBA. Among them, the oil port DP of the second relief valve 9 is connected to the output oil port of the second hydraulic pump 7, the oil port DT is connected to the main oil tank 1, and the oil port DX is connected to the oil port BP of the second two-position four-way solenoid valve 10; the oil port BT and the oil port BA of the second two-position four-way solenoid valve 10 are both connected to the main oil tank 1, and the oil port BB is blocked.

[0037] like Figure 1As shown, when the electromagnet YVBA of the second two-position four-way solenoid valve 10 loses power, its oil port BP is connected to the oil port BA, the oil port BB is connected to the oil port BT, the oil port DX of the second relief valve 9 is connected to the main oil tank 1 through the oil port BP and the oil port BA of the second two-position four-way solenoid valve 10, and the second relief valve 9 is in a unloading state. On the contrary, when the electromagnet YVBA of the second two-position four-way solenoid valve 10 is energized, its oil port BP is connected to the oil port BB, the oil port BA is connected to the oil port BT, the oil port DX of the second relief valve 9 is blocked after passing through the oil ports BP and the oil port BB of the second two-position four-way solenoid valve 10, and the second relief valve 9 is in a pressure-building state.

[0038] like Figure 1 As shown, the hydraulic control valve group 02 includes a first electro-hydraulic reversing valve 12, a first hydraulically controlled non-return valve 13, a two-position two-way solenoid valve 14, a first throttle valve 15, and oil ports XP, XT, EF, EG, and its oil port XP is connected to the oil port UP of the main oil supply device 01, and the oil port XT is connected to the oil port UT of the main oil supply device 01. Among them, the first electro-hydraulic reversing valve 12 includes oil ports EP, ET, EA, EB and electromagnets YVEA, YVEB, the first hydraulically controlled non-return valve 13 includes oil ports EC, ED, EX, and the two-position two-way solenoid valve 14 includes oil ports FA, FP and electromagnet YVFA.

[0039] like Figure 1 As shown, the oil port EP of the first electro-hydraulic reversing valve 12 is connected to the oil port XP, the oil port ET is connected to the oil port XT, the oil port EA is connected to the oil port EC of the first hydraulically controlled one-way valve 13, the oil port EB is connected to the oil port EG and the oil port EX of the first hydraulically controlled one-way valve 13, and the oil port ED of the first hydraulically controlled one-way valve 13 is connected to the oil port EF. The oil port FP of the two-position two-way solenoid valve 14 is connected to the oil port EF, and the oil port FA is connected to the oil port XT through the first throttle valve 15.

[0040] like Figure 1 As shown, when the electromagnets YVEA and YVEB of the first electro-hydraulic reversing valve 12 are both de-energized, the oil port EP is blocked, and the oil ports ET, EA, and EB are interconnected; when the electromagnet YVEA of the first electro-hydraulic reversing valve 12 is energized and YVEB is de-energized, the oil port EP is connected to the oil port EB, and the oil port EA is connected to the oil port ET; when the electromagnet YVEA of the first electro-hydraulic reversing valve 12 is de-energized and YVEB is energized, the oil port EP is connected to the oil port EA, and the oil port EB is connected to the oil port ET. When the electromagnet YVFA of the two-position two-way solenoid valve 14 is de-energized, the oil port FP is disconnected from the oil port FA, and vice versa, when the electromagnet YVFA is energized, the oil port FP is connected to the oil port FA.

[0041] like Figure 1As shown, the hydraulic control valve group 02 also includes a first pressure reducing valve 16, a second electro-hydraulic reversing valve 17, a second hydraulically controlled one-way valve 18 and oil ports YP, GF, GG, and its oil port YP is connected to the oil port VP of the main oil supply device 01. Among them, the first pressure reducing valve 16 includes oil ports GJ and oil port GK, the second electro-hydraulic reversing valve 17 includes oil ports GP, GT, GA, GB and electromagnets YVGA, YVGB, and the second hydraulically controlled one-way valve 18 includes oil ports GC, GD, GX.

[0042] like Figure 1 As shown, the oil port GJ of the first pressure reducing valve 16 is connected with the oil port YP, the oil port GK is connected with the oil port GP of the second electro-hydraulic reversing valve 17, the oil port GT of the second electro-hydraulic reversing valve 17 is connected with the oil port XT, the oil port GA is connected with the oil port GF and the oil port GX of the second hydraulically controlled one-way valve 18 respectively, the oil port GB is connected with the oil port GC of the second hydraulically controlled one-way valve 18, and the oil port GD of the second hydraulically controlled one-way valve 18 is connected with the oil port GG.

[0043] like Figure 1 As shown, when the electromagnets YVGA and YVGB of the second electro-hydraulic reversing valve 17 are both de-energized, the oil port GP is blocked, and the oil ports GT, GA, and GB are interconnected; when the electromagnet YVGA of the second electro-hydraulic reversing valve 17 is energized and YVGB is de-energized, the oil port GP is connected to the oil port GB, and the oil port GA is connected to the oil port GT; when the electromagnet YVGA of the second electro-hydraulic reversing valve 17 is de-energized and YVGB is energized, the oil port GP is connected to the oil port GA, and the oil port GB is connected to the oil port GT.

[0044] like Figure 1 As shown, the hydraulic control valve group 02 also includes a servo proportional valve 19, a third hydraulically controlled one-way valve 20 and an oil port GH. The servo proportional valve 19 includes oil ports HP, HT, HA, HB and a proportional electromagnet YVHA. The third hydraulically controlled one-way valve 20 includes oil ports HC, HD and HX. Among them, the oil port HP of the servo proportional valve 19 is connected to the oil port YP, the oil port HT is connected to the oil port XT, the oil port HA is connected to the oil port HC of the third hydraulically controlled one-way valve 20, the oil port HB is blocked, and the oil port HD of the third hydraulically controlled one-way valve 20 is connected to the oil port GH. By changing the input signal size of the proportional electromagnet YVHA of the servo proportional valve 19, the flow direction and opening size of the servo proportional valve 19 are changed.

[0045] like Figure 1As shown, the hydraulic control valve group 02 also includes a second throttle valve 21, a second pressure reducing valve 22 and a third two-position four-way solenoid valve 23. The second pressure reducing valve 22 includes an oil port JC and an oil port JD. The third two-position four-way solenoid valve 23 includes oil ports JP, JT, JA, JB and an electromagnet YVJA. The oil port JC of the second pressure reducing valve 22 is connected to the oil port YP of the hydraulic control valve group 02 through the second throttle valve 21, and the oil port JD of the second pressure reducing valve 22 is connected to the oil port JP of the third two-position four-way solenoid valve 23. The oil port JT of the third two-position four-way solenoid valve 23 is connected to the oil port XT, the oil port JA is blocked, and the oil port JB is connected to the oil port HX of the third hydraulically controlled one-way valve 20.

[0046] like Figure 1 As shown, when the electromagnet YVJA of the third two-position four-way solenoid valve 23 loses power, its oil port JP is connected with the oil port JA, and the oil port JB is connected with the oil port JT; conversely, when the electromagnet YVJA is energized, its oil port JP is connected with the oil port JB, and the oil port JA is connected with the oil port JT.

[0047] like Figure 1 As shown, the actuator component 03 includes a water pressure booster cylinder 24, which includes an oil port MA connected to its rodless chamber, an oil port MB connected to its rod chamber, a water inlet MC and a pressurized water output port MD, and the oil port MA is connected to the oil port EF of the hydraulic control valve group 02, the oil port MB is connected to the oil port EG of the hydraulic control valve group 02, and the pressurized water output port MD is connected to the inner cavity of the measured pipe and is connected to a first pressure sensor 25.

[0048] like Figure 1 As shown, the actuator assembly 03 also includes a main seal clamping cylinder 26 and two auxiliary hydraulic cylinders 27 symmetrically arranged on both sides of the main seal clamping cylinder 26. The piston rod of the main seal clamping cylinder 26 is fixedly connected to the piston rods of the two auxiliary hydraulic cylinders 27. The rod chambers of the two auxiliary hydraulic cylinders 27 are connected and connected to the oil port GF of the hydraulic control valve group 02, and the rodless chambers are connected and connected to the oil port GG of the hydraulic control valve group 02. The oil port of the main seal clamping cylinder 26 is connected to the oil port GH of the hydraulic control valve group 02 and is connected to the second pressure sensor 28. Among them, the first pressure sensor 25 and the second pressure sensor 28 are connected to the proportional solenoid YVHA of the servo proportional valve 19 for communication feedback control.

[0049] like Figure 1 As shown, the auxiliary oil supply device 04 includes an auxiliary oil tank 29 and a filling valve 30, the auxiliary oil tank 29 includes a high-level oil port ST, and the high-level oil port ST is connected to the oil port VT of the main oil tank 1; the filling valve 30 includes oil ports SA, SB, and SX, and the oil port SA is connected to the bottom of the auxiliary oil tank 29, the oil port SB is connected to the oil port of the main sealing clamping cylinder 26, and the oil port SX is connected to the rod chamber of the two auxiliary hydraulic cylinders 27 and the oil port GF of the hydraulic control valve group 02.

[0050] Working principle and usage of the utility model:

[0051] 1. Pre-clamping of pipe end seal: The electromagnet YVBA of the second two-position four-way solenoid valve 10 and the YVGA of the second electro-hydraulic reversing valve 17 are energized, the oil port BP of the second two-position four-way solenoid valve 10 is connected with the oil port BB, the oil port BA is connected with the oil port BT, the second overflow valve 9 is in a pressure-building state, adjusting the maximum output pressure of the second hydraulic pump 7, the oil port GP of the second electro-hydraulic reversing valve 17 is connected with the oil port GB, and the oil port GA is connected with the oil port GT.

[0052] The hydraulic oil in the main oil tank 1 passes through the second hydraulic pump 7, the second non-return valve 11, the oil port VP, the oil port YP, the oil port GJ and the oil port GK of the first pressure reducing valve 16, the oil port GP and the oil port GB of the second electro-hydraulic reversing valve 17, the oil port GC, the oil port GD and the oil port GG of the second hydraulic control non-return valve 18, and enters the rodless chambers of the two auxiliary hydraulic cylinders 27. The hydraulic oil in the rod chambers of the two auxiliary hydraulic cylinders 27 passes through the oil port GF, the oil port GA of the second electro-hydraulic reversing valve 17, and the oil port GC, the oil port GD and the oil port GG of the second hydraulic control non-return valve 18. , oil port GT, oil port XT, oil port UT return to the main oil tank 1, the piston rods of the two auxiliary hydraulic cylinders 27 extend, and drive the piston rod of the main sealing clamping cylinder 26 to extend, and at the same time, the oil port of the main sealing clamping cylinder 26 sucks open the filling valve 30 under the action of negative pressure, and the hydraulic oil of the auxiliary oil tank 29 enters the oil port of the main sealing clamping cylinder 26 through the oil port SA and oil port SB of the filling valve 30, realizing the pre-clamping of the pipe end seal, wherein the pre-clamping pressure is adjusted by the first pressure reducing valve 16.

[0053] 2. Filling the pipe under test with water: The inner cavity of the tested tube is filled with water from the water inlet MC of the water pressure boosting cylinder 24 .

[0054] 3. Water pressure boosting: The electromagnet YVAA of the first two-position four-way solenoid valve 5 and YVEB of the first electro-hydraulic reversing valve 12 are energized, the oil port AP of the first two-position four-way solenoid valve 5 is connected with the oil port AB, the oil port AA is connected with the oil port AT, the first overflow valve 4 is in a pressure building state, adjusting the maximum output pressure of the first hydraulic pump 2, the oil port EP of the first electro-hydraulic reversing valve 12 is connected with the oil port EA, and the oil port EB is connected with the oil port ET. The hydraulic oil in the main oil tank 1 passes through the first hydraulic pump 2, the first one-way valve 6, the oil port UP, the oil port XP, the oil port EP of the first electro-hydraulic reversing valve 12, the oil port EA, the oil port EC of the first hydraulically controlled one-way valve 13, the oil port ED, the oil port EF, and the oil port MA of the water pressure boosting cylinder 24 to enter the rodless chamber of the water pressure boosting cylinder 24; the hydraulic oil in the rod chamber of the water pressure boosting cylinder 24 passes through its oil port MB, the oil port EG, the oil port EB of the first electro-hydraulic reversing valve 12, the oil port ET, the oil port XT, and the oil port UT to return to the main oil tank 1 to achieve water pressure boosting.

[0055] At the same time, YVBA of the second two-position four-way solenoid valve 10 and YVGA of the second electro-hydraulic reversing valve 17 are energized, and YVJA of the third two-position four-way solenoid valve 23 is energized, the oil ports JP and JB of the third two-position four-way solenoid valve 23 are connected, the oil ports JA and JT are connected, the pipe end seal pre-clamping continues to be maintained, and the hydraulic oil of the oil port YP is also sent to the oil port HX of the third hydraulically controlled one-way valve 20 through the second throttle valve 21, the oil port JC and the oil port JD of the second pressure reducing valve 22, and the oil ports JP and JB of the third two-position four-way solenoid valve 23. The third hydraulically controlled one-way valve 20 is opened, and its oil port HC is connected to the oil port HD.

[0056] 4. Sealing clamping pressure balance: While the water pressure is being boosted, the first pressure sensor 25 detects the water pressure signal at the boost water output port and feeds it back to the controller, thereby calculating the required pressure at the oil port of the main sealing clamping cylinder 26 and the input current parameter of the proportional solenoid YVHA of the servo proportional valve 19, controlling the opening of the servo proportional valve 19, and pressurizing the hydraulic oil at the oil port YP to the oil port of the main sealing clamping cylinder 26 through the servo proportional valve 19 and the third hydraulically controlled one-way valve 20. Based on the error between the actual pressure at the oil port of the main sealing clamping cylinder 26 detected by the second pressure sensor 28 and the required pressure, the input signal of the servo proportional valve 19 is controlled and adjusted to ensure that the actual pressure at the oil port of the main sealing clamping cylinder 26 is the same as the required pressure. At this time, the water pressure acting on the pipeline seal is balanced with the clamping force of the main sealing clamping cylinder 26, and the axial force on the tested pipe fitting is the pre-compression force generated by the auxiliary hydraulic cylinder 27.

[0057] 5. Maintaining pressure: All electromagnets and proportional electromagnets in the main oil supply device 01 and the hydraulic control valve group 02 are de-energized, the pressure is maintained, and the condition of the tested pipe is observed.

[0058] 6. Pressure reduction and pressure maintenance: The tested pipe may be damaged if subjected to ultra-high pressure for a long time. After the short ultra-high pressure test, the pressure reduction test is carried out. The electromagnet YVBA of the second two-position four-way solenoid valve 10, the YVFA of the two-position two-way solenoid valve 14, and the YVJA of the third two-position four-way solenoid valve 23 are energized, the oil port BP of the second two-position four-way solenoid valve 10 is connected to the oil port BB, the oil port BA is connected to the oil port BT, the oil port FP of the two-position two-way solenoid valve 14 is connected to the oil port FA, the oil ports JP and JB of the third two-position four-way solenoid valve 23 are connected, and the oil port JA is connected to the oil port JT.

[0059] The hydraulic oil in the rodless chamber of the water pressure booster cylinder 24 slowly returns to the main oil tank 1 through its oil port MA, oil port EF, oil port FP of the two-position two-way solenoid valve 14, oil port FA, the first throttle valve 15, oil port XT, and oil port UT, the water pressure in the inner cavity of the test tube slowly decreases, and the oil port MB of the rod chamber of the water pressure booster cylinder 24 draws oil from the main oil tank 1 through the oil port EG, oil port EB of the first electro-hydraulic reversing valve 12, oil port ET, oil port XT, and oil port UT.

[0060] The same as the above-mentioned sealing clamping pressure balancing function, under the cooperation of the first pressure sensor 25 and the second pressure sensor 28, the servo proportional valve 19 is controlled to adjust the oil port pressure of the main sealing clamping cylinder 26. When the water pressure drops to the set pressure, all electromagnets and proportional electromagnets lose power, maintain the pressure, and observe the condition of the tested pipe.

[0061] 7. Pressure relief: Same as the pressure reduction function above, reduces water pressure to a minimum.

[0062] 8. Reset: The electromagnet YVAA of the first two-position four-way solenoid valve 5, the YVBA of the second two-position four-way solenoid valve 10, the YVEA of the first electro-hydraulic reversing valve 12, and the YVGB of the second electro-hydraulic reversing valve 17 are energized, the oil port AP of the first two-position four-way solenoid valve 5 is connected with the oil port AB, the oil port AA is connected with the oil port AT, the oil port EP of the first electro-hydraulic reversing valve 12 is connected with the oil port EB, the oil port EA is connected with the oil port ET, the oil port BP of the second two-position four-way solenoid valve 10 is connected with the oil port BB, the oil port BA is connected with the oil port BT, the oil port GP of the second electro-hydraulic reversing valve 17 is connected with the oil port GA, and the oil port GB is connected with the oil port GT.

[0063] The hydraulic oil in the main oil tank 1 enters the rod chamber of the water pressure booster cylinder 24 through the first hydraulic pump 2, the first non-return valve 6, the oil port UP, the oil port XP, the oil port EP of the first electro-hydraulic reversing valve 12, the oil port EB, the oil port EG, and the oil port MB of the water pressure booster cylinder 24 in sequence. At the same time, the hydraulic oil also enters the oil port EX of the first hydraulic control non-return valve 13 from the oil port EB of the first electro-hydraulic reversing valve 12. The first hydraulic control non-return valve 13 opens, and its oil port EC is connected to the oil port ED. The hydraulic oil in the rodless chamber of the water pressure booster cylinder 24 returns to the main oil tank 1 from its oil port MA, oil port EF, the oil port ED of the first hydraulic control non-return valve 13, the oil port EC, the oil port EA of the first electro-hydraulic reversing valve 12, the oil port ET, the oil port XT, and the oil port UT.

[0064] At the same time, the hydraulic oil in the main oil tank 1 passes through the second hydraulic pump 7, the second one-way valve 11, the oil port VP, the oil port YP, the oil port GJ of the first pressure reducing valve 16, the oil port GK, the oil port GP of the second electro-hydraulic reversing valve 17, and the oil port GA, and enters the oil port GX of the second hydraulically controlled one-way valve 18 and the oil port GF of the hydraulic control valve group 02 respectively, and enters the rod chamber of the auxiliary hydraulic cylinder 27 and the oil port SX of the filling valve 30 from the oil port GF respectively. The second hydraulically controlled one-way valve 18 is opened, and its oil port GC is connected to the oil port GD. The filling valve 30 is opened, and its oil port SA is connected to the oil port SB.

[0065] The hydraulic oil in the rodless chamber of the auxiliary hydraulic cylinder 27 returns to the main oil tank 1 through the oil port GG, the oil port GD of the first hydraulically controlled one-way valve 13, the oil port GC, the oil port GB of the second electro-hydraulic reversing valve 17, the oil port GT, the oil port XT, and the oil port UT, the piston rod of the auxiliary hydraulic cylinder 27 retracts, and drives the piston rod of the main sealing clamping cylinder 26 to retract, and the hydraulic oil at the oil port of the main sealing clamping cylinder 26 returns to the auxiliary oil tank 29 through the oil port SB and the oil port SA of the filling valve 30, thereby completing the resetting of the water pressure boosting cylinder 24, the main sealing clamping cylinder 26 and the auxiliary hydraulic cylinder 27.

[0066] The above description shows and describes the preferred embodiments of the utility model. As mentioned above, it should be understood that the utility model is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the utility model concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not depart from the spirit and scope of the utility model, and should be within the scope of protection of the claims attached to the utility model.

Claims

1. A hydraulic system for a pipe pressure testing machine, characterized in that: The invention comprises a main oil supply device (01), a hydraulic control valve group (02), an actuator component (03) and an auxiliary oil supply device (04), wherein the main oil supply device (01) is connected to the actuator component (03) via the hydraulic control valve group (02), and the auxiliary oil supply device (04) is connected to the actuator component (03); The main oil supply device (01) comprises a main oil tank (1), a first hydraulic pump (2), a second hydraulic pump (7) and oil ports UP, VP, UT and VT. The oil ports UT and VT are in communication with the main oil tank (1). The oil input ports of the first hydraulic pump (2) and the second hydraulic pump (7) are in communication with the main oil tank (1). The first hydraulic pump (2) is connected to a first motor (3) and the second hydraulic pump (7) is connected to a second motor (8). The oil output port of the first hydraulic pump (2) is in communication with the oil port UP and a first non-return valve (6) is provided therebetween. The oil output port of the second hydraulic pump (7) is in communication with the oil port VP and a second non-return valve (11) is provided therebetween. The hydraulic control valve group (02) comprises a first electro-hydraulic reversing valve (12), a first hydraulically controlled non-return valve (13), a two-position two-way solenoid valve (14), oil ports XP, YP, XT, EF, EG, GF, GG, GH, and the oil ports XP, YP, XT are respectively connected to the oil ports UP, VP, UT of the main oil supply device (01) in a one-to-one correspondence; The first electro-hydraulic reversing valve (12) comprises oil ports EP, ET, EA, EB and electromagnets YVEA, YVEB; the first hydraulically controlled one-way valve (13) comprises oil ports EC, ED, EX; the two-position two-way solenoid valve (14) comprises oil ports FA, FP and electromagnet YVFA; The oil port EP of the first electro-hydraulic reversing valve (12) is connected to the oil port XP, the oil port ET is connected to the oil port XT, the oil port EA is connected to the oil port EC of the first hydraulically controlled non-return valve (13), and the oil port EB is connected to the oil port EG and the oil port EX of the first hydraulically controlled non-return valve (13); the oil port ED of the first hydraulically controlled non-return valve (13) and the oil port FP of the two-position two-way solenoid valve (14) are respectively connected to the oil port EF, and the oil port FA of the two-position two-way solenoid valve (14) is connected to the oil port XT; The hydraulic control valve group (02) further comprises a second electro-hydraulic directional control valve (17) and a second hydraulically controlled non-return valve (18), wherein the second electro-hydraulic directional control valve (17) comprises oil ports GP, GT, GA, GB and electromagnets YVGA, YVGB, and the second hydraulically controlled non-return valve (18) comprises oil ports GC, GD, GX; The oil port GP of the second electro-hydraulic reversing valve (17) is connected to the oil port YP, the oil port GT is connected to the oil port XT, the oil port GA is connected to the oil port GF and the oil port GX of the second hydraulically controlled one-way valve (18) respectively, the oil port GB is connected to the oil port GC of the second hydraulically controlled one-way valve (18), and the oil port GD of the second hydraulically controlled one-way valve (18) is connected to the oil port GG; The hydraulic control valve group (02) further comprises a servo proportional valve (19), a third hydraulically controlled one-way valve (20) and a third two-position four-way solenoid valve (23); the servo proportional valve (19) comprises oil ports HP, HT, HA, HB and a proportional solenoid YVHA; the third hydraulically controlled one-way valve (20) comprises oil ports HC, HD, HX; the third two-position four-way solenoid valve (23) comprises oil ports JP, JT, JA, JB and an solenoid YVJA; The oil port HP of the servo proportional valve (19) is connected to the oil port YP, the oil port HT is connected to the oil port XT, the oil port HA is connected to the oil port HC of the third hydraulically controlled one-way valve (20), the oil port HB is blocked, and the oil port HD of the third hydraulically controlled one-way valve (20) is connected to the oil port GH; the oil port JP of the third two-position four-way solenoid valve (23) is connected to the oil port YP, the oil port JT is connected to the oil port XT, the oil port JA is blocked, and the oil port JB is connected to the oil port HX of the third hydraulically controlled one-way valve (20); The actuator assembly (03) comprises a water pressure boost cylinder (24), a main sealing clamping cylinder (26) and two auxiliary hydraulic cylinders (27) symmetrically arranged on both sides of the main sealing clamping cylinder (26); the piston rod of the main sealing clamping cylinder (26) is fixedly connected to the piston rods of the two auxiliary hydraulic cylinders (27); the rod chambers of the two auxiliary hydraulic cylinders (27) are in communication with each other and are in communication with the oil port GF of the hydraulic control valve group (02), and the rodless chambers are in communication with each other and are in communication with the oil port GG of the hydraulic control valve group (02); The water pressure boosting cylinder (24) comprises an oil port MA connected to its rodless cavity, an oil port MB connected to its rod cavity, a water inlet MC and a boosting water output port MD, and the oil port MA is connected to the oil port EF of the hydraulic control valve group (02), the oil port MB is connected to the oil port EG of the hydraulic control valve group (02), and the boosting water output port MD is connected to the inner cavity of the pipe to be tested and is connected to a first pressure sensor (25); The oil port of the main sealing clamping cylinder (26) is in communication with the oil port GH of the hydraulic control valve group (02), and is connected to a second pressure sensor (28); the first pressure sensor (25) and the second pressure sensor (28) are connected to the proportional solenoid YVHA of the servo proportional valve (19) for communication feedback control; The auxiliary oil supply device (04) includes an auxiliary oil tank (29) and a filling valve (30), wherein the high-position oil port ST of the auxiliary oil tank (29) is connected to the oil port VT of the main oil tank (1); the filling valve (30) includes oil ports SA, SB, and SX, wherein the oil port SA is connected to the bottom of the auxiliary oil tank (29), the oil port SB is connected to the oil port of the main sealing clamping cylinder (26), and the oil port SX is connected to the rod chambers of the two auxiliary hydraulic cylinders (27) and the oil port GF of the hydraulic control valve group (02).

2. A hydraulic system for a pipe pressure testing machine according to claim 1, characterized in that: The main oil supply device (01) further comprises a first overflow valve (4) and a first two-position four-way solenoid valve (5); the first overflow valve (4) comprises oil ports CP, CT and CX; the first two-position four-way solenoid valve (5) comprises oil ports AP, AT, AA and AB and an electromagnet YVAA; the oil port CP of the first overflow valve (4) is connected to the output oil port of the first hydraulic pump (2), the oil port CT is connected to the main oil tank (1), and the oil port CX is connected to the oil port AP of the first two-position four-way solenoid valve (5); the oil ports AT and AA of the first two-position four-way solenoid valve (5) are both connected to the main oil tank (1), and the oil port AB is blocked.

3. The hydraulic system for a pipe pressure testing machine according to claim 1, characterized in that: The main oil supply device (01) also includes a second overflow valve (9) and a second two-position four-way solenoid valve (10), wherein the second overflow valve (9) includes oil ports DP, DT, and DX, and the second two-position four-way solenoid valve (10) includes oil ports BP, BT, BA, BB, and an electromagnet YVBA; the oil port DP of the second overflow valve (9) is connected to the output oil port of the second hydraulic pump (7), the oil port DT is connected to the main oil tank (1), and the oil port DX is connected to the oil port BP of the second two-position four-way solenoid valve (10); the oil port BT and the oil port BA of the second two-position four-way solenoid valve (10) are both connected to the main oil tank (1), and the oil port BB is blocked.

4. The hydraulic system for a pipe pressure testing machine according to claim 1, characterized in that: A first throttle valve (15) is also provided between the oil port FA of the two-position two-way solenoid valve (14) and the oil port XT of the hydraulic control valve group (02).

5. The hydraulic system for a pipe pressure testing machine according to claim 1, characterized in that: A first pressure reducing valve (16) is provided between the oil port GP of the second electro-hydraulic reversing valve (17) and the oil port YP of the hydraulic control valve group (02); the first pressure reducing valve (16) comprises an oil port GJ and an oil port GK, and the oil port GK is connected to the oil port GP of the second electro-hydraulic reversing valve (17), and the oil port GJ is connected to the oil port YP of the hydraulic control valve group (02).

6. The hydraulic system for a pipe pressure testing machine according to claim 1, characterized in that: A second throttle valve (21) is also provided between the oil port JP of the third two-position four-way solenoid valve (23) and the oil port YP of the hydraulic control valve group (02).

7. A hydraulic system for a pipe pressure testing machine according to claim 6, characterized in that: A second pressure reducing valve (22) is provided between the oil port JP of the third two-position four-way solenoid valve (23) and the second throttle valve (21), and the second pressure reducing valve (22) comprises an oil port JC and an oil port JD, wherein the oil port JC is communicated with the second throttle valve (21), and the oil port JD is communicated with the oil port JP of the third two-position four-way solenoid valve (23).

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