CN103062024B

CN103062024B - High-low-pressure switching method for double-cylinder pumping device, hydraulic control system of double-cylinder pumping device and device

Info

Publication number: CN103062024B
Application number: CN201210574745.XA
Authority: CN
Inventors: 曹奎; 周小宾; 李华; 王佳茜
Original assignee: Zoomlion Heavy Industry Science and Technology Co Ltd
Current assignee: Zoomlion Heavy Industry Science and Technology Co Ltd
Priority date: 2012-12-26
Filing date: 2012-12-26
Publication date: 2014-12-10
Anticipated expiration: 2032-12-26
Also published as: CN103062024A

Abstract

A high-low-pressure switching method for a double-cylinder pumping device includes that, firstly, high-pressure pumping operation of the double-cylinder pumping device is stopped so as to enable the double-cylinder pumping device to keep a high-pressure pumping to-be-switched stated for first preset delay time ta; secondly, a rodless cavity of a first main oil cylinder and a rodless cavity of a second main oil cylinder are communicated with each other to form a communicated cavity, a cavity with a rod of the first main oil cylinder and a cavity with a rod of the second main oil cylinder are communicated with a first working oil path and a second working oil path respectively so as to enable the double-cylinder pumping device to keep a low-pressure pumping preparing state for second preset delay time tb; and thirdly, the double-cylinder pumping device is in a low-pressure pumping operation state. In addition, the invention further provides a hydraulic control system of the double-cylinder pumping device and a pumping device. Sequential control of high-low-pressure switching is achieved, certain buffering time is kept after a corresponding step, operation is conducted after a system oil path is stabilized, hydraulic impact is effectively relieved, and the main oil cylinders can work stably.

Description

The high low pressure switching method of twin-tub pumping installations and hydraulic control system and equipment

Technical field

The present invention relates to a kind of controlling method of twin-tub pumping installations, particularly, relate to a kind of high low pressure switching method of twin-tub pumping installations.In addition the pumping equipment that, the invention still further relates to a kind of hydraulic control system of twin-tub pumping installations and comprise this hydraulic control system.Twin-tub pumping installations of the present invention is mainly used in the pumping of sticky material, typically concrete pump for example.

Background technique

The sticky material such as concrete, mud is the conventional structural material in engineering construction field, these sticky materials typically undertaken pumpings by twin-tub pumping installations (such as concrete pump, mortar pump etc.), twin-tub pumping installations is mainly by the control of its hydraulic control system, so that sticky material is carried continuously along pipeline.

In order to help to understand, typically, for example, with Concrete Double cylinder pumping installations, Concrete Double cylinder pumping installations generally comprises two master cylinders (also referred to as " master hydraulic cylinder "), two conveying cylinders (also referred to as " concrete cylinder "), two pumping pistons, two oscillating oil cylinders, hopper and distributing valves, these parts are assembled together, and form Concrete Double cylinder pumping installations.With regard to the hydraulic control system of this Concrete Double cylinder pumping installations, mainly refer to and be connected to corresponding hydraulic control circuit on master cylinder and oscillating oil cylinder.

Particularly, for example, the rod chamber of two master cylinders is interconnected, rodless cavity is connected to main reversing valve, this main reversing valve is connected in main oil-feed oil circuit and fuel tank, by the commutation of main reversing valve, optionally make the rodless cavity of the first master cylinder in two master cylinders be communicated with main oil-feed oil circuit and the rodless cavity of the second master cylinder is communicated with fuel tank, or the rodless cavity of the first master cylinder is communicated with and the second main rodless cavity of oily 5 is communicated with main oil-feed oil circuit with fuel tank.Because the rod chamber of two master cylinders is interconnected and is closed with hydraulic oil, hydraulic oil in the rod chamber of these two master cylinders plays the effect of driving medium, thereby by alternately realizing the alternately flexible of two master cylinders to the rodless cavity oil-feed of two master cylinders.Two pumping pistons 1 lay respectively at two and carry in cylinders and be connected to drive corresponding pumping piston 1 alternating motion with the piston rod of master cylinder respectively, for example, with alternately pumping or suction sticky material, concrete.

At this, it should be noted that, the rod chamber that two master cylinders are not limited to two above-mentioned master cylinders is interconnected to form the situation of communicated cavity, selectively, the rodless cavity that also can adopt two master cylinders is interconnected and forms the structural type of communicated cavity, and the rod chamber of two master cylinders forms actuator chamber respectively and is connected with selector valve in this case.For those skilled in the art knownly, the rod chamber that makes two master cylinders is interconnected and rodless cavity is high pressure pumping state as the situation of actuator chamber, and the rodless cavity of two master cylinders is interconnected and rod chamber is low pressure pumping state as the situation of actuator chamber.

In actual twin-tub pumping installations, the rodless cavity of two master cylinders or rod chamber can by switching, optionally as communicated cavity or actuator chamber, this generally realizes by high/low pressure cut-over valve.The high/low pressure cut-over valve adopting in the hydraulic control system of twin-tub pumping installations can have various ways, is not limited to the high/low pressure cut-over valve that six two-way plug-in valves of the employing shown in Fig. 1 form.

But, in the high low pressure handoff procedure of current twin-tub pumping installations, often each control valve in the hydraulic control system of twin-tub pumping installations is switched simultaneously by force, this causes when carrying out high low pressure switching, hydraulic shock in hydraulic control system is very large, and master cylinder work is not steady, and the hydraulic oil of communicated cavity sealing changes larger in different handoff procedures, can not control relatively stablely, and then cause master cylinder to drive stroke elongated or shorten.That is to say, existing twin-tub pumping installations, in high low pressure handover operation process, is not to operate according to relatively scientific and reasonable operating procedure, but optionally carries out high low pressure switching, and this has caused the shortcoming of above-mentioned twin-tub pumping installations.Especially, for example, when there is plugging phenomenon or having plugging trend in sticky material delivery pipe (concrete delivery pipe), twin-tub pumped difficulty, now blindly, random low high pressure switches, tend to aggravate the degree of plugging, make system overpressure, even occur the serious accidents such as booster.

In view of the above-mentioned defect of prior art, need to provide a kind of high low pressure switching method of twin-tub pumping installations of science more.

Summary of the invention

The present invention's technical problem first to be solved is to provide a kind of high low pressure switching method of twin-tub pumping installations, and it is more steadily reliable that this high low pressure switching method can make the high low pressure of twin-tub pumping installations switch, thereby improve pumpdown quality.

Further, technical problem to be solved by this invention is to provide a kind of hydraulic control system of twin-tub pumping installations, and the high low pressure that this hydraulic control system can realize twin-tub pumping installations more reliably switches.

In addition, the technical problem that the present invention also will solve is to provide a kind of pumping equipment, and the twin-tub pumping installations of this pumping equipment can be realized more reliably high low pressure and switch, and makes the service behaviour of pumping equipment more stable.

In order to solve the problems of the technologies described above, a kind of form of implementation of switching for be sent to low pressure pumping from high-pressure service pump as high low pressure switching method of the present invention, the invention provides a kind of high low pressure switching method of twin-tub pumping installations, the hydraulic control system of described twin-tub pumping installations comprises the first and second working oil path of the first and second master cylinder oil inlet and oil returns that are respectively used to this twin-tub pumping installations, alternately oil-feed and the oil return of this first and second working oil path, to realize the alternately flexible of described the first and second master cylinders, wherein, described high low pressure switching method comprises the steps: first, under state at described twin-tub pumping installations in high pressure pumpdown, make described the first and second working oil path stop conveying liquid force feed, to stop the high pressure pumpdown of described twin-tub pumping installations, thereby make this twin-tub pumping installations in the to be switched state of high pressure pumping, and keep the first scheduled delay ta at the to be switched state of this high pressure pumping, the second, make described the first and second master cylinders rodless cavity separately be interconnected to form communicated cavity, and this communicated cavity is all ended with respect to described the first and second working oil path, and the rod chamber of described the first master cylinder and the rod chamber of described the second master cylinder are relative to each other ended, and the rod chamber of this first master cylinder is communicated with described the first working oil path, the rod chamber of this second master cylinder is communicated with described the second working oil path, thereby make described twin-tub pumping installations in low pressure pumping readiness, and keep the second scheduled delay tb at this low pressure pumping readiness, the 3rd, by described the first and second working oil path, make the rod chamber of described the first master cylinder and alternately oil-feed and the oil return of the rod chamber of the second master cylinder, thereby make described twin-tub pumping installations in low pressure pumping job state.

As a kind of preferred form, the hydraulic control system of described twin-tub pumping installations is open hydraulic control system, wherein said the first and second working oil path are connected in main oil-feed oil circuit and main oil return circuit via main reversing valve, in described first step, when stopping the high pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit, high pressure pumping in the first working oil path or the second working oil path stops oil pressure constantly, and according to this high pressure pumping, stop oil pressure constantly and determine the first scheduled delay ta in described first step and the second scheduled delay tb in described second step by inquiry experts database, or the hydraulic control system of described twin-tub pumping installations is Closed Hydraulic control system, wherein said the first and second working oil path are connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, with by the positive and negative of described oil hydraulic pump then make the one oil-feed in described the first and second working oil path, another one oil return, in described first step, the high pressure pumping detecting when stopping the high pressure pumpdown of described twin-tub pumping installations in described the first working oil path or the second working oil path stops oil pressure constantly, and according to this high pressure pumping, stop oil pressure constantly and determine the first scheduled delay ta in described first step and the second scheduled delay tb in described second step by inquiry experts database, described experts database comprises that each high pressure pumping stops corresponding the first scheduled delay value of oil pressure value and the second scheduled delay value constantly.

Preferably, described the first scheduled delay ta and the second scheduled delay tb are respectively 0-10s.

Preferably, described the first and second working oil path are connected in described the first and second master cylinders via high/low pressure cut-over valve respectively, in described second step, the switching by described high/low pressure cut-over valve makes described twin-tub pumping installations in described low pressure pumping readiness.

Preferably, the hydraulic control system of described twin-tub pumping installations is open hydraulic control system, and wherein said the first and second working oil path are connected in main oil-feed oil circuit and main oil return circuit via main reversing valve; In described first step, by controlling described main reversing valve, described the first and second working oil path and described main oil-feed oil circuit and main oil return circuit are all ended, thereby make this first and second working oil path stop conveying liquid force feed; In described third step, by control described main reversing valve make described the first and second working oil path alternately with described main oil-feed oil circuit and main oil return circuit) one and another one be communicated with, thereby by described the first and second working oil path, make the rod chamber of described the first master cylinder and alternately oil-feed and the oil return of the rod chamber of the second master cylinder.

Preferably, described main reversing valve is O type three position four-way directional control valve.

Particularly, described twin-tub pumping installations is Concrete Double cylinder pumping installations.

A kind of form of implementation of switching for be sent to high pressure pumping from low pressure pump as high low pressure switching method of the present invention, the invention provides a kind of high low pressure switching method of twin-tub pumping installations, the hydraulic control system of described twin-tub pumping installations comprises the first and second working oil path of the first and second master cylinder oil inlet and oil returns that are respectively used to this twin-tub pumping installations, alternately oil-feed and the oil return of this first and second working oil path, to realize the alternately flexible of described the first and second master cylinders, wherein, described high low pressure switching method comprises the steps: first, under state at described twin-tub pumping installations in low pressure pumpdown, make described the first and second working oil path stop conveying liquid force feed, to stop the low pressure pumpdown of described twin-tub pumping installations, thereby make this twin-tub pumping installations in the to be switched state of low pressure pumping, and keep the first scheduled time ta ' at the to be switched state of this low pressure pumping, the second, make described the first and second master cylinders rod chamber separately be interconnected to form communicated cavity, and this communicated cavity is all ended with respect to described the first and second working oil path, and the rodless cavity of described the first master cylinder and the rodless cavity of described the second master cylinder are relative to each other ended, and the rodless cavity of this first master cylinder is communicated with described the first working oil path, the rodless cavity of this second master cylinder is communicated with described the second working oil path, thereby make described twin-tub pumping installations in high pressure pumping readiness, and keep the second scheduled time tb ' at this high pressure pumping readiness, the 3rd, by described the first and second working oil path, make the rodless cavity of described the first master cylinder and alternately oil-feed and the oil return of the rodless cavity of the second master cylinder, thereby make described twin-tub pumping installations in high pressure pumping job state.

As a kind of preferred form, the hydraulic control system of described twin-tub pumping installations is open hydraulic control system, wherein said the first and second working oil path are connected in main oil-feed oil circuit and main oil return circuit via main reversing valve, in described first step, when stopping the low pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit, low pressure pumping in the first working oil path or the second working oil path stops oil pressure constantly, and according to this low pressure pumping, stop oil pressure constantly and determine the first scheduled time ta ' in described first step and the second scheduled time tb ' in described second step by inquiry experts database, or the hydraulic control system of described twin-tub pumping installations is Closed Hydraulic control system, wherein said the first and second working oil path are connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, with by the positive and negative of described oil hydraulic pump then make the one oil-feed in described the first and second working oil path, another one oil return, in described first step, the low pressure pumping detecting when stopping the low pressure pumpdown of described twin-tub pumping installations in described the first working oil path or the second working oil path stops oil pressure constantly, and according to this low pressure pumping, stop oil pressure constantly and determine the first scheduled time ta ' in described first step and the second scheduled time tb ' in described second step by inquiry experts database, described experts database comprises that each low pressure pumping stops corresponding the first scheduled time value of oil pressure value and the second scheduled time value constantly.

Preferably, described the first scheduled time ta ' and the second scheduled time tb ' are respectively 0-10s.

Preferably, described the first and second working oil path are connected in described the first and second master cylinders via high/low pressure cut-over valve respectively, in described second step, the switching by described high/low pressure cut-over valve makes described twin-tub pumping installations in described high pressure pumping readiness.

Preferably, the hydraulic control system of described twin-tub pumping installations is open hydraulic control system, and wherein said the first and second working oil path are connected in main oil-feed oil circuit and main oil return circuit via main reversing valve; In described first step, by controlling described main reversing valve, described the first and second working oil path and described main oil-feed oil circuit and main oil return circuit are all ended, thereby make this first and second working oil path stop conveying liquid force feed; In described third step, by control described main reversing valve make described the first and second working oil path alternately with described main oil-feed oil circuit and main oil return circuit) one and another one be communicated with, thereby by described the first and second working oil path, make the rodless cavity of described the first master cylinder and alternately oil-feed and the oil return of the rodless cavity of the second master cylinder.

Particularly,, described twin-tub pumping installations is Concrete Double cylinder pumping installations.

Further, the invention provides a kind of hydraulic control system of twin-tub pumping installations, comprise automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity of the first master cylinder and rodless cavity and the rod chamber of rod chamber and the second master cylinder of described twin-tub pumping installations by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path and the second working oil path, this first working oil path and the second working oil path are connected in main oil-feed oil circuit and main oil return circuit by the main reversing valve of electric control reversing valve form, wherein, described hydraulic control system also comprises controller, this controller is electrically connected on described main reversing valve and automatically controlled high/low pressure cut-over valve, described controller is used for receiving operational order so that described twin-tub pumping installations is switched to low pressure pumping or is switched to high pressure pumping from low pressure pumping from high pressure pumping, and this controller is controlled according to following sequential: first, control described main reversing valve and stop the current pumpdown carrying out, and keep pumpdown halted state the first predetermined hold-time, the second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and after high low pressure state switches, keep the second predetermined hold-time, the 3rd, control described main reversing valve so that described twin-tub pumping installations carries out pumpdown.

Preferably, described main oil-feed oil circuit, in the first working oil path or the second working oil path, be provided with oil pressure detection device, this oil pressure detection device is electrically connected on described controller so that the fuel injection pressure signal of detection is transferred to this controller, the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to described oil pressure detection device stops fuel injection pressure signal constantly and determines described the first predetermined hold-time and the second predetermined hold-time by inquiry experts database, described experts database is stored in described controller or in external server, this experts database comprises that each pumping stops corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value constantly.

Form of implementation as the hydraulic control system of another kind of twin-tub pumping installations, the present invention also provides the hydraulic control system of twin-tub pumping installations, comprise automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity of the first master cylinder and rodless cavity and the rod chamber of rod chamber and the second master cylinder of described twin-tub pumping installations by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path and the second working oil path, this first working oil path and the second working oil path are connected in the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, with by the positive and negative of described oil hydraulic pump then make the one oil-feed in described the first and second working oil path, another one oil return, wherein, described hydraulic control system also comprises controller, this controller is electrically connected on automatically controlled rotating driving device and the automatically controlled high/low pressure cut-over valve of described oil hydraulic pump, described controller is used for receiving operational order so that described twin-tub pumping installations is switched to low pressure pumping or is switched to high pressure pumping from low pressure pumping from high pressure pumping, and this controller is controlled according to following sequential: first, control the automatically controlled rotating driving device of described oil hydraulic pump to stop the current pumpdown carrying out, and keep pumpdown halted state the first predetermined hold-time, the second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and high low pressure state switches rear second predetermined hold-time that keeps, the 3rd, control the automatically controlled rotary actuation of described oil hydraulic pump so that described twin-tub pumping installations carries out pumpdown.

Preferably, , in described the first working oil path or the second working oil path, be provided with oil pressure detection device, this oil pressure detection device is electrically connected on described controller so that the fuel injection pressure signal of detection is transferred to this controller, the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to described oil pressure detection device stops fuel injection pressure signal constantly and determines described the first predetermined hold-time and the second predetermined hold-time by inquiry experts database, described experts database is stored in described controller or in external server, this experts database comprises that each pumping stops corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value constantly.

In addition, the invention provides a kind of pumping equipment, it comprises the hydraulic control system of twin-tub pumping installations and this twin-tub pumping installations, and wherein, described hydraulic control system is above-mentioned hydraulic control system.

Pass through technique scheme, high low pressure switching method of the present invention with respect to existing techniques in realizing accurate time-oriented sequential control, make to stop pumping, high low pressure handover operation, and restart pumpdown and carry out according to predetermined sequential, this has been avoided in prior art when high low pressure switches simultaneously or has carried out disorderly a plurality of control actions, and by keep certain buffer time after corresponding operating procedure, after making the oil circuit of hydraulic control system stable, carry out again next step operation, this has alleviated the hydraulic shock in hydraulic control system effectively, make master cylinder stable working, and in handoff procedure, make the hydraulic oil in communicated cavity relatively stable, thereby make master cylinder drive stroke to keep constant relative efficiency.The high low pressure that high low pressure switching method of the present invention can be applied to the twin-tub pumping installations of various existing forms at large switches, and it has general applicability and using value, and especially it can adopt automatically controlled form, thereby realize automatically, controls.

Other features and advantages of the present invention partly in detail are described the embodiment subsequently.

Accompanying drawing explanation

Following accompanying drawing is used to provide a further understanding of the present invention, and forms a part for specification, and itself and following embodiment one are used from explanation the present invention, but protection scope of the present invention is not limited to following the drawings and the specific embodiments.In the accompanying drawings:

Fig. 1 is the hydraulic schematic diagram of hydraulic control system of the twin-tub pumping installations of the specific embodiment of the invention.

Fig. 2 is the control sequential chart that the high low pressure of the hydraulic control system shown in Fig. 1 switches.

Fig. 3 is the step block diagram of the high low pressure switching method of the specific embodiment of the invention, and the high low pressure switching method of this embodiment is used for controlling twin-tub pumping installations and switches from high pressure pumping job state to low pressure pumping job state.

Fig. 4 is the step block diagram of the high low pressure switching method of the another kind of embodiment of the present invention, and the high low pressure switching method of this embodiment is used for controlling twin-tub pumping installations and switches from low pressure pumping job state to high pressure pumping job state.

Description of reference numerals:

1 first master cylinder; 1a rodless cavity;

1b rod chamber; 2 second master cylinders;

2a rodless cavity; 2b rod chamber;

3 main reversing valves; 4 oil pressure detection devices;

5 main oil-feed oil circuits; 6 main oil return circuits;

7 first working oil path; 8 second working oil path;

9 switch hydraulic control oil circuit selector valve; 10 switch with hydraulic control oil-feed oil circuit;

11 switching hydraulic control oil return circuits; 12 first pilot-controlled working oil circuits;

13 second pilot-controlled working oil circuits; 14 pilot-actuated valves;

15 guide's oil-feed oil circuits; 16 guide's oil return circuits;

17 first guide's pilot-controlled working oil circuits; 18 second guide's pilot-controlled working oil circuits.

Embodiment

Below in conjunction with accompanying drawing, the specific embodiment of the present invention is elaborated, should be understood that, embodiment described herein is only for description and interpretation the present invention, and protection scope of the present invention is not limited to following embodiment.

Major technique design of the present invention is to provide a kind of high low pressure switching method of twin-tub pumping installations, makes the high low pressure switching of twin-tub pumping installations controlled in order, thereby improves the smooth operation that high low pressure switches, and improves pumpdown quality.It should be noted that, although Fig. 1 of the present invention has shown a kind of high/low pressure cut-over valve form of twin-tub pumping installations, but the technical conceive of high low pressure switching method of the present invention is not limited to adopt the hydraulic control system shown in Fig. 1 to realize, because the hydraulic connecting structure of the hydraulic control system of twin-tub pumping installations is substantially similar, also there are various known forms in high/low pressure cut-over valve, we's high low pressure switching method can be applicable to the high low pressure switching controls of twin-tub pumping installations at large, therefore, any twin-tub pumping installations, specific constructive form regardless of its hydraulic control system, as long as adopt high low pressure switching method of the present invention, it all belongs to protection scope of the present invention.In addition, the term of " the high pressure pumping " and " low pressure pumping " described in below describing, for the general standard term of art of those skilled in the art, wherein " high pressure pumping " refer to that the rod chamber of the first and second master cylinders of twin-tub pumping installations is interconnected and using as communicated cavity, and rodless cavity is as the situation of actuator chamber, " low pressure pumping " refers to that the rodless cavity of the first and second master cylinders is interconnected and usings as communicated cavity, and rod chamber is as the situation of actuator chamber, so-called " high pressure " is relative technological concept with " low pressure ", it is mainly to refer under main oil-feed oil circuit oil pressure and the basicly stable situation of flow, the outlet pressure of the sticky material of pumping.

In order to help to understand, first twin-tub pumping installations and hydraulic control system thereof are below described, it should be noted that, the structure of relevant twin-tub pumping installations and hydraulic control system thereof is similar substantially, thus the following high low pressure switching method of the present invention can be at large for the switching controls of twin-tub pumping installations.

Shown in Figure 1, as mentioned above, the main structure of twin-tub pumping installations is known ground, and it generally comprises two master cylinders (i.e. the first master cylinder 1 and the second master cylinder 2), two conveying cylinders (also referred to as " concrete cylinder "), two pumping pistons, two oscillating oil cylinders, hopper and distributing valves.Wherein, carry cylinder, pumping piston, oscillating oil cylinder, hopper and distributing valve etc. not to show in Fig. 1, the technical conceive of the high low pressure switching method that it is following with the present invention is not directly related, therefore at this, only simply describes.Briefly, two pumping pistons lay respectively in two conveying cylinders and respectively and connect with the piston rod of the first and second master cylinders 1,2, to pass through the first and second master cylinders 1,2 drive corresponding pumping piston alternating motion, thus alternately pumping or suction sticky material.Carry the material mouth of cylinder by distributing valve, to be connected in discharge port and the material conveying pipe (for example concrete conveying pipe) of hopper for two, distributing valve drives by oscillating oil cylinder, so that carry the material mouth of cylinder to be optionally communicated with discharge port or the material conveying pipe of hopper.In addition, the hydraulic control circuit of above-mentioned oscillating oil cylinder is uncorrelated with technical conceive of the present invention, therefore when below describing hydraulic control system, will not describe.

With regard to the hydraulic control system of twin-tub pumping installations, its hydraulic connecting structure is similarly substantially, particularly, the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and rod chamber 1b and the second master cylinder 2 is connected high/low pressure cut-over valve (having the corresponding hydraulic fluid port that connects on high/low pressure cut-over valve) by pipeline respectively with rod chamber 2b, this high/low pressure cut-over valve is connected in the first working oil path 7 and the second working oil path 8, and this first working oil path 7 and the second working oil path 8 are connected in main oil-feed oil circuit 5 and main oil return circuit 6 by main reversing valve 3.Uniquely, on the main oil-feed oil circuit 5 of the hydraulic control system of twin-tub pumping installations of the present invention, be provided with oil pressure detection device 4, such as oil pressure sensor or oil pressure gauge etc., wherein oil pressure sensor can be electrically connected in controller or display unit.

Wherein, there is in the prior art various ways in high/low pressure cut-over valve, such as disclosed high/low pressure cut-over valve in CN200520109691.5, CN01273407.1, CN200320101853.1 etc., its fundamental function is all identical, by controlling high/low pressure cut-over valve, can optionally make twin-tub pumping installations in high pressure pumping state or low pressure pumping state.Particularly, at described low pressure pumping state, by the switching of described high/low pressure cut-over valve, the rodless cavity 1a of the first master cylinder 1 and the rodless cavity 2a of the second master cylinder 2 are interconnected usings as communicated cavity, and this communicated cavity seals with respect to outside, and the rod chamber 1b of the rod chamber 1b of the first master cylinder 1 and the second master cylinder 2 is communicated with the first working oil path 7 and the second working oil path 8 respectively; Under described high pressure pumping state, by the switching of described high/low pressure cut-over valve, the rod chamber 1b of the first master cylinder 1 and the rod chamber 2b of the second master cylinder 2 are interconnected usings as communicated cavity, and this communicated cavity seals with respect to outside, and the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 is communicated with the first working oil path 7 and the second working oil path 8 respectively.At this, it should be noted that, the statement of above-mentioned " connection ", belong to a kind of statement of simplifying, the technological concept of its expression is the implication of " hydraulic oil can two-way flow by ", for example, the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 is interconnected, and that is to say that the interior hydraulic oil of rodless cavity 1a of the first master cylinder 1 can flow in the rodless cavity 2a of the second master cylinder 2, and vice versa; For another example, the rodless cavity 1a of the first master cylinder 1 is communicated with the first working oil path 7, when the hydraulic oil in the first working oil path 7 can flow to the rodless cavity 1a(rodless cavity 1a oil-feed of the first master cylinder 1), on the contrary hydraulic oil in the rodless cavity 1a of the first master cylinder 1 also can flow to (during rodless cavity 1a oil return) in the first working oil path 7.That is to say, the concept of above-mentioned " connection ", can be both the state of oil circuit in normal open, can be also on oil circuit, to have relevant valve, but thereby can open the state that can realize connection under the effect of this valve mobile hydraulic oil on described oil circuit.For example, in six formed high/low pressure cut-over valves of two-way plug-in valve of the employing shown in Fig. 1, when liquid controling cavity (the being Returnning spring chamber) decompression of the first two-way plug-in valve C1, hydraulic oil in the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 all can be pushed the spool of the first two-way plug-in valve C1 open when twin-tub pumping installations is worked, and realizes connected state.Therefore, the implication that above-mentioned " connection " should can two-way flow from the hydraulic oil of essence is understood, and should not carry out unreasonably narrow definition, below this is repeated no more.

The first working oil path 7 and the second working oil path 8 are connected in main reversing valve 3, as shown in Figure 1, main reversing valve 3 at least comprises oil inlet P, oil return inlet T, the first actuator port A and the second actuator port B that connects main oil-feed oil circuit 5, main oil return circuit 6, the first working oil path 7 and the second working oil path 8 for correspondence.By the switching of main reversing valve 3, the first working oil path 7 and the second working oil path 8 are alternately born the function of oil-feed and oil return, by the commutation of main reversing valve 3, control, when the first working oil path 7 is communicated with main oil-feed oil circuit 5 and the second working oil path 8 while being communicated with main oil return circuit 6, the first working oil path 7 is receiving liquid force feed from main oil-feed oil circuit 5, and rodless cavity 1a or rod chamber 1b(that hydraulic oil is fed to the first master cylinder 1 are determined according to high pressure pumping state and low pressure pumping state), the rodless cavity 2a of the second master cylinder 2 or rod chamber 2b via the second working oil path 8 to main oil return circuit 6 oil returns.When switching to, main reversing valve 3 the first working oil path 7 is communicated with and the second working oil path 8 while being communicated with main oil-feed oil circuit 5 with main oil return circuit 6, the oil inlet and oil return process of twin-tub pumping installations is contrary to the above, thereby realize the alternately flexible of the first and second master cylinders 1,2.Main reversing valve 3 generally can adopt O type three position four-way directional control valve, can certainly adopt the selector valve of other form, and this knows for those skilled in the art.Main reversing valve 3 adopts O type three position four-way directional control valve, when carrying out high low pressure switching, when main reversing valve 3 is switched to meta when fuel cut-off and oil return, the rodless cavity 1a of the first master cylinder 1 or rodless cavity 2a or the rod chamber 2b of rod chamber 1b and the second master cylinder 2 as actuator chamber in front and continued working procedure can be closed with hydraulic oil, work as by the switching of high/low pressure cut-over valve like this, and make in front and continued working procedure to be interconnected and during as communicated cavity as the rodless cavity 1a of the first master cylinder 1 of actuator chamber or the rodless cavity 2a of rod chamber 1b and the second master cylinder 2 or rod chamber 2b, in this communicated cavity, can be full of by hydraulic oil, using in follow-up pumping procedure as the driving medium in communicated cavity.

Shown in Figure 1, main reversing valve 3 can adopt the selector valve of various ways, such as solenoid directional control valve, hand-operated direction valve, guide's hyraulic controlled type selector valve etc.For example, main reversing valve 3 in Fig. 1 is guide's hyraulic controlled type O type three position four-way directional control valve, wherein the hydraulic control mouth at main reversing valve 3 two ends is connected to first guide's pilot-controlled working oil circuit 17 and second guide's pilot-controlled working oil circuit 18, this the first guide pilot-controlled working oil circuit 17 and second guide's pilot-controlled working oil circuit 18 are connected in guide's oil-feed oil circuit 15 and guide's oil return circuit 16 via the pilot-actuated valve 14 of selector valve form, by the switching of pilot-actuated valve 14, can selectively make first guide's pilot-controlled working oil circuit 17 be communicated with guide's oil-feed oil circuit 15 and second guide's pilot-controlled working oil circuit 18 is communicated with guide's oil return circuit 16, or first guide's pilot-controlled working oil circuit 17 is communicated with and second guide's pilot-controlled working oil circuit 18 is communicated with guide's oil-feed oil circuit 15 with guide's oil return circuit 16.Like this by the switching controls of pilot-actuated valve 14, guide's hydraulic control oil optionally can be fed to the one of hydraulic control mouth at the two ends of main reversing valve 3, another one is carried out oil return, thereby switches by the commutation that hydraulic control mode is controlled main reversing valve 3.Pilot-actuated valve 14 can adopt the selector valve of various ways, and it at least comprises oil inlet P 2, oil return inlet T 2, the first actuator port A2 and the second actuator port B2 that connects guide's oil-feed oil circuit 15, guide's oil return circuit 16, first guide's pilot-controlled working oil circuit 17 and second guide's pilot-controlled working oil circuit 18 for correspondence.In Fig. 1, pilot-actuated valve 14 is 3-position 4-way solenoid directional control valve, by control the both sides electromagnet YW3 of this 3-position 4-way solenoid directional control valve and YW4 electric or power failure state, can realize easily the commutation of this 3-position 4-way solenoid directional control valve.In addition, guide's oil return circuit 16 generally can be connected to fuel tank or or the main oil return circuit 6(of hydraulic control system its be also connected in fuel tank), due to the needed hydraulic control of pilot control oil oil pressure and flow all relatively little, guide's oil-feed oil circuit 15 generally can be connected on special hydraulic control oil sources, for example, on the pumping oil circuit of special small-scale liquid press pump or the hydraulic control oil feeding line of construction machinery hydraulic system, or also can connect Yi Ge branch oil circuit from main oil-feed oil circuit 5, via or via reduction valve, be not connected on this guide's oil-feed oil circuit 15.In addition, the switching shown in following Fig. 1 is also similarly with the hydraulic control oil sources that hydraulic control oil-feed oil circuit 10 connects, as long as meet hydraulic control, drives object, this for the technician of Hydraulic Field without repeating.

As mentioned above, described high/low pressure cut-over valve can adopt the high/low pressure cut-over valve of various known forms.High/low pressure cut-over valve can be connected by oil circuit by the valve disperseing, but be more generally the form that forms combination valve, be on high/low pressure cut-over valve, to there is corresponding interface, each interface on this high/low pressure cut-over valve is connected in the first and second master cylinders 1 via corresponding oil circuit respectively, 2 rod chamber 1b separately, 2b and rodless cavity 1a, the first actuator port A of the interface of 2a and main reversing valve 3 and the second actuator port B.For example, in Fig. 1, described high/low pressure cut-over valve consists of six two-way plug-in valves and switching hydraulic control oil circuit selector valve 9, six two-way plug-in valves are the first two-way plug-in valve C1, the second two-way plug-in valve C2, the 3rd two-way plug-in valve C3, the 4th two-way plug-in valve C4, the 5th two-way plug-in valve C5 and the 6th two-way plug-in valve C6, it should be noted that, thisly by six two-way plug-in valves and corresponding switching, with the high/low pressure cut-over valve that hydraulic control oil circuit selector valve 9 forms, belong to a kind of high/low pressure cut-over valve more common in engineering machinery, in Fig. 1, in order to clearly illustrate its high low pressure switching principle, shown its hydraulic connecting theory structure, it does not represent actual mechanical entities linkage structure, in actual use, this high/low pressure cut-over valve generally forms the form of combination valve, each interface on this high/low pressure cut-over valve is connected in the first and second master cylinders 1 via corresponding oil circuit respectively, 2 rod chamber 1b separately, 2b and rodless cavity 1a, the first actuator port A of the interface of 2a and main reversing valve 3 and the second actuator port B, generally speaking, as long as those skilled in the art are mentioned to the high/low pressure cut-over valve that comprises six two-way plug-in valves, can know clearly the hydraulic connecting relation that it is relevant, CN102330665A for example.

In order to help to understand the handoff procedure of high/low pressure cut-over valve, referring to the hydraulic schematic diagram of the high/low pressure cut-over valve shown in Fig. 1, describe briefly.Relevant two-way plug-in valve belongs to the known hydraulic element of Hydraulic Field, does not repeat them here.Wherein, the first port of the first two-way plug-in valve C1 is communicated with the rodless cavity 2a of the second master cylinder 2, and the second port is communicated with the rodless cavity 1a of the first master cylinder 1; The first port of the second two-way plug-in valve C2 is communicated with the rod chamber 2b of the second master cylinder 2, and the second port is communicated with the rod chamber 1b of the first master cylinder 1; The first port of the 6th two-way plug-in valve C6 is communicated with the first actuator port A of main reversing valve 3, and the second port is communicated with the rod chamber 1b of the first master cylinder 1; The first port of the 4th two-way plug-in valve C4 is communicated with the first actuator port A of main reversing valve 3, and the second port is communicated with the rodless cavity 1a of the first master cylinder 1; The first port of the 5th two-way plug-in valve C5 is communicated with the second actuator port B of main reversing valve 3, and the second port is communicated with the rod chamber 2b of the second master cylinder 2; The first port of the 3rd two-way plug-in valve C3 is communicated with the second actuator port B of main reversing valve 3, and the second port is communicated with the rodless cavity 2a of the second master cylinder 2.In addition, the hydraulic control mouth of above-mentioned six two-way plug-in valves is connected to and switches hydraulic control oil circuit, particularly, for example, in Fig. 1, switch hydraulic control oil circuit and comprise the 3-position 4-way solenoid directional control valve for both sides in switching hydraulic control oil circuit selector valve 9(Fig. 1 with electromagnet YW1 and YW2, it can certainly be the selector valve of other form, two-position four way change valve for example), in above-mentioned six two-way plug-in valves second, the third and fourth two-way plug-in valve C2, C3, the hydraulic control mouth of C4 is connected in the first actuator port A1 that switches hydraulic control oil circuit selector valve 9 via the first pilot-controlled working oil circuit 12, first, the the 5th and the 6th two-way plug-in valve C1, C5, the hydraulic control mouth of C6 is connected in the second actuator port B1 that switches hydraulic control oil circuit selector valve 9 via the second pilot-controlled working oil circuit 13, the oil inlet P 1 of this switching hydraulic control oil circuit selector valve 9 is connected in to be switched with hydraulic control oil-feed oil circuit 10, oil return inlet T 1 is connected in to be switched with hydraulic control oil return circuit 11.

Like this, as shown in Figure 1, when switch hydraulic control oil circuit selector valve 9 by control, make second, the third and fourth two-way plug-in valve C2, C3, the hydraulic control mouth of C4 is communicated with hydraulic control oil return circuit 11 with switching via the first pilot-controlled working oil circuit 12, and first, the the 5th and the 6th two-way plug-in valve C1, C5, the hydraulic control mouth of C6 via the second pilot-controlled working oil circuit 13 with switch with hydraulic control oil-feed oil circuit 10 be communicated with (for example the electromagnet YW2 of the 3-position 4-way solenoid directional control valve of the switching of the conduct in Fig. 1 hydraulic control oil circuit selector valve 9 obtain electric, and electromagnet YW1 dead electricity), thereby second, the third and fourth two-way plug-in valve C2, C3, C4 is in state that can bidirectional opening, and first, the the 5th and the 6th two-way plug-in valve C1, C5, C6 is because the effect locking of hydraulic control oil is closed, in this case, the rod chamber 2b of the rod chamber 1b of the first master cylinder 1 and the second master cylinder 2 is interconnected as communicated cavity, the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 is communicated with the first working oil path 7 and the second working oil path 8 respectively, now by controlling main reversing valve 3, control the first working oil path 7 and alternately oil-feed and the oil return of the second working oil path 8, thereby make the first master cylinder 1 and the second master cylinder 2 alternately flexible, now in so-called high pressure pumping state, when switch hydraulic control oil circuit selector valve 9 by control, make second, the third and fourth two-way plug-in valve C2, C3, the hydraulic control mouth of C4 is communicated with hydraulic control oil-feed oil circuit 10 with switching via the first pilot-controlled working oil circuit 12, and first, the the 5th and the 6th two-way plug-in valve C1, C5, the hydraulic control mouth of C6 is communicated with (for example conduct in Fig. 1 switch the electromagnet YW2 dead electricity of the 3-position 4-way solenoid directional control valve of hydraulic control oil circuit selector valve 9, and electromagnet YW1 obtain electric) with switching with hydraulic control oil return circuit 11 via the second pilot-controlled working oil circuit 13, thereby second, the third and fourth two-way plug-in valve C2, C3, C4 is locking due to the effect of hydraulic control oil, and first, the the 5th and the 6th two-way plug-in valve C1, C5, C6 is in state that can bidirectional opening, in this case, the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 is interconnected as communicated cavity, the rod chamber 2b of the rod chamber 1b of the first master cylinder 1 and the second master cylinder 2 is communicated with the first working oil path 7 and the second working oil path 8 respectively, now by controlling main reversing valve 3, control the first working oil path 7 and alternately oil-feed and the oil return of the second working oil path 8, thereby make the first master cylinder 1 and the second master cylinder 2 alternately flexible, now in so-called low pressure pumping state.

The typical hydraulic structure of twin-tub pumping installations of the present invention has more than been described, emphasis is described the unique texture feature of the hydraulic control system of the twin-tub pumping installations that embodies the technology of the present invention design below, particularly, under the situation that is open type hydraulic system in the hydraulic control system of twin-tub pumping installations of the present invention, shown in Figure 1, to above-described similar, the hydraulic control system of described twin-tub pumping installations comprises automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity 1a of the first master cylinder 1 and rodless cavity 2a and the rod chamber 2b of rod chamber 1b and the second master cylinder 2 of described twin-tub pumping installations by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path 7 and the second working oil path 8, this first working oil path 7 and the second working oil path 8 are connected in main oil-feed oil circuit 5 and main oil return circuit 6 by the main reversing valve 3 of electric control reversing valve form, as key technical feature, hydraulic control system of the present invention also comprises controller, this controller is electrically connected on described main reversing valve 3 and automatically controlled high/low pressure cut-over valve, described controller is used for receiving operational order, such as operator in Fig. 1 by input device (such as operating grip etc.) so that described twin-tub pumping installations is switched to low pressure pumping or is switched to high pressure pumping from low pressure pumping from high pressure pumping, and this controller is controlled according to following sequential: first, control main reversing valve 3 and stop the current pumpdown carrying out, and keep pumpdown halted state the first predetermined hold-time, the second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and after high low pressure state switches, keep the second predetermined hold-time, the 3rd, control described main reversing valve so that described twin-tub pumping installations carries out pumpdown.

Above-mentioned the first predetermined hold-time and the second predetermined hold-time switch for open hydraulic control system, Closed Hydraulic control system, from high pressure pumping state to low pressure pumping state and switch and have certain differentiation from low pressure pumping state and high pressure pumping state, and this will describe in more detail in controlling method below.The first predetermined hold-time and the second predetermined hold-time can be determined according to the experience of engineering construction, generally make oil circuit there is enough oil circuit stabilization time after switching according to the order of sequence, be unlikely again the continuity that too affects pumpdown, generally can in 1-10s, choose.More preferably, shown in Figure 1, can in main oil-feed oil circuit 5, the first working oil path 7 or the second working oil path 8, be provided with for example oil pressure sensor of oil pressure detection device 4(), this oil pressure detection device 4 is electrically connected on controller so that the fuel injection pressure signal of detection is transferred to this controller, and the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to oil pressure detection device 4 stops fuel injection pressure signal constantly and determines the first predetermined hold-time and the second predetermined hold-time by inquiry experts database.Experts database belongs to a kind of database or the control table relatively extensively adopting on engineering mechanical device, it generally determines the corresponding relation of relevant parameter by a large amount of simulated condition tests, thereby after a parameter is determined, controller can be determined the preferred value of other parameter corresponding with this parameter by inquiry experts database.Particularly, described experts database can be stored in described controller or in external server, this experts database comprises that each pumping stops corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value constantly, in this case, because the first predetermined hold-time value and the second predetermined hold-time value are all the more satisfactory measured values that obtain by actual simulated condition test, thereby can make oil circuit there is enough oil circuit stabilization time, the continuity requirement of balance pumpdown relatively reliably again after switching according to the order of sequence.

In addition, at technical conceive of the present invention, be applied under the situation of Closed Hydraulic control system, known ground, Closed Hydraulic control system mainly by the positive and negative of oil hydraulic pump then the oil inlet and oil return of realizing the first working oil path 7 and the second working oil path 8 switch, particularly, in this case, the hydraulic control system of twin-tub pumping installations of the present invention comprises automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity 1a of the first master cylinder 1 and rodless cavity 2a and the rod chamber 2b of rod chamber 1b and the second master cylinder 2 of described twin-tub pumping installations by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path 7 and the second working oil path 8, this first working oil path 7 and the second working oil path 8 are connected in the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, with by the positive and negative of described oil hydraulic pump then make described the first and second working oil path 7, one oil-feed in 8, another one oil return, similar with above-mentioned open hydraulic control system, described hydraulic control system also comprises controller, this controller is electrically connected on automatically controlled rotating driving device (being generally motor to control by controller easily) and the automatically controlled high/low pressure cut-over valve of described oil hydraulic pump, described controller is used for receiving operational order so that described twin-tub pumping installations is switched to low pressure pumping or is switched to high pressure pumping from low pressure pumping from high pressure pumping, and this controller is controlled according to following sequential: first, control the automatically controlled rotating driving device of described oil hydraulic pump to stop the current pumpdown carrying out, and keep pumpdown halted state the first predetermined hold-time, the second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and high low pressure state switches rear second predetermined hold-time that keeps, the 3rd, control the automatically controlled rotary actuation of described oil hydraulic pump so that described twin-tub pumping installations carries out pumpdown.

At this, it should be noted that, because Closed Hydraulic control system does not exist main oil-feed oil circuit (having repairing oil circuit in actual hydraulic pressure system), therefore, above-mentioned oil pressure detection device 4 can be arranged in the first working oil path 7 or the second working oil path 8, this oil pressure detection device 4 is electrically connected on described controller so that the fuel injection pressure signal of detection is transferred to this controller, the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to described oil pressure detection device stops fuel injection pressure signal constantly and determines described the first predetermined hold-time and the second predetermined hold-time by inquiry experts database, described experts database is stored in described controller or in external server, this experts database comprises that each pumping stops corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value constantly.

In addition, relevant by controller the switching controls for the main reversing valve 3 of automatically controlled high/low pressure cut-over valve and electric control reversing valve form, know for those skilled in the art, be generally by control the electromagnet of the respective valve in automatically controlled high/low pressure cut-over valve and electric control reversing valve both sides electromagnet electric power failure state, and control spool, move to realize oil circuit and control.

In addition, as mentioned above, on the main oil-feed oil circuit 1 of the hydraulic control system of twin-tub pumping installations of the present invention, be also provided with oil pressure detection device, this can judge whether normal work according to fuel injection pressure signal, thereby make the service behaviour of twin-tub pumping installations more reliable, especially when plugging appears in Material pipeline, the rising of abnormal oil pressure by this oil pressure detection device, can be detected, thereby can avoid carrying out blindly high low pressure switching.Further, pumping equipment of the present invention comprises the hydraulic control control system of the twin-tub pumping installations of twin-tub pumping installations and above-mentioned form.

Above with reference to Fig. 1 has described the main structure of twin-tub pumping installations and the high low pressure realized by its hydraulic control system switches hydraulic control process.The high low pressure switching method of twin-tub pumping installations of the present invention is described on the basis of the above.

Referring to Fig. 1, shown in Fig. 2 and Fig. 3, as mentioned above, the hydraulic control system of described twin-tub pumping installations comprises main oil-feed oil circuit 5 and main oil return circuit 6, this main oil-feed oil circuit 5 and main oil return circuit 6 generally can be connected in the first and second working oil path 7 via main reversing valve 3, 8, can make this first and second working oil path 7, 8 are alternately communicated with one and another one in main oil-feed oil circuit 5 and main oil return circuit 6 simultaneously, thereby make this first and second working oil path 7, 8 alternately oil-feed and oil return (make the first and second working oil path 7, one oil-feed in 8, another one oil return simultaneously), this first and second working oil path 7, 8 are respectively used to the first and second master cylinders 1 of described twin-tub pumping installations, 2 oil inlet and oil return (being that hydraulic oil is carried), thereby realize this first and second master cylinder 1, 2 alternately stretch.

The first form of implementation as high low pressure switching method of the present invention, it is mainly used in twin-tub pumping installations to be switched to low pressure pumping state from high pressure pumping state, particularly, the high low pressure switching method of the twin-tub pumping installations of this first form of implementation comprises the steps:

First, under state at described twin-tub pumping installations in high pressure pumpdown, make described the first and second working oil path 7,8 all end (making the first and second working oil path stop conveying liquid force feed) with described main oil-feed oil circuit 5 and main oil return circuit 6, to stop the high pressure pumpdown of described twin-tub pumping installations, thereby make this twin-tub pumping installations in the to be switched state of high pressure pumping, and keep the first scheduled delay ta at the to be switched state of this high pressure;

The second, make described the first and second master cylinders 1,2 rodless cavity 1a separately, 2a is interconnected to form communicated cavity, and this communicated cavity is all ended with respect to described the first and second working oil path 7,8; And the rod chamber 1b of described the first master cylinder 1 and the rod chamber 2b of described the second master cylinder 2 are relative to each other ended, and the rod chamber 1b of described the first master cylinder 1 is communicated with described the first working oil path 7, the rod chamber 2b of described the second master cylinder 2 is communicated with described the second working oil path 8, thereby make described twin-tub pumping installations in low pressure pumping readiness, and keep the second scheduled delay tb at this low pressure pumping readiness;

The 3rd, make described the first and second working oil path 7,8 are alternately communicated with one and the another one of described main oil-feed oil circuit 5 and main oil return circuit 6, realize alternately oil-feed and oil return, thereby by the first and second working oil path 7,8 make alternately oil-feed and the oil return of rod chamber 2b of rod chamber 1b and second master cylinder 2 of the first master cylinder 1, thereby make described twin-tub pumping installations in low pressure pumping job state.

In the form of implementation of above-mentioned high low pressure switching method, it will be appreciated that, the above-mentioned high low pressure switching method key that makes twin-tub pumping installations be switched to low pressure pumping state from high pressure pumping state of the present invention is to realize a kind of time-oriented sequential control, make to stop high pressure pumping, low pressure handover operation, and restart pumpdown and carry out according to predetermined sequential, this has been avoided in prior art when high low pressure switches simultaneously or has carried out disorderly a plurality of control actions, and for example, by keep certain buffer time (the first scheduled delay ta and the second scheduled delay tb) after each operating procedure, after making the oil circuit of hydraulic control system stable, carry out again next step operation, this has alleviated the hydraulic shock in hydraulic control system effectively, make master cylinder stable working, and in handoff procedure, make the hydraulic oil that switches the communicated cavity inner sealing forming keep relative stablizing, thereby make master cylinder drive stroke to keep constant relative efficiency.At this, it should be noted that, in fact in above-mentioned high low pressure switching method of the present invention, the time-oriented sequential control that has realized according to the order of sequence priority of each step, therefore above-mentioned the first scheduled delay ta and the second scheduled delay tb can be included as zero situation, typically, described the first scheduled delay ta and the second scheduled delay tb can be respectively 0-10s.

About determining of described the first scheduled delay ta and the second scheduled delay tb, more preferably, as described above, hydraulic control system at described twin-tub pumping installations is under the situation of open hydraulic control system, described the first and second working oil path 7, 8 are connected in main oil-feed oil circuit 5 and main oil return circuit 6 via main reversing valve 3, in described first step, when stopping the high pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit 5, high pressure pumping in the first working oil path 7 or the second working oil path stops oil pressure constantly, and according to this high pressure pumping, stop oil pressure constantly and determine the first scheduled delay ta in above-mentioned first step and the second scheduled delay tb in described second step by inquiry experts database.As another kind of situation, hydraulic control system at described twin-tub pumping installations is under the situation of Closed Hydraulic control system, described the first and second working oil path 7, 8 are connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, with by the positive and negative of described oil hydraulic pump then make described the first and second working oil path 7, one oil-feed in 8, another one oil return, in above-mentioned first step, the high pressure pumping detecting when stopping the high pressure pumpdown of described twin-tub pumping installations in described the first working oil path 7 or the second working oil path stops oil pressure constantly, and according to this high pressure pumping, stop oil pressure constantly and determine the first scheduled delay ta in described first step and the second scheduled delay tb in described second step by inquiry experts database.Described experts database comprises that each high pressure pumping stops corresponding the first scheduled delay value of oil pressure value and the second scheduled delay value constantly, that is to say, this first scheduled delay ta and the second scheduled delay tb are that above-mentioned hydraulic control system adopts corresponding the first predetermined hold-time and the second predetermined hold-time the control procedure that is sent to low pressure pumping switching from high-pressure service pump.

Typically, described the first and second working oil path 7,8 are connected in described the first and second master cylinders 1,2 via high/low pressure cut-over valve respectively, in above-mentioned second step, the switching by described high/low pressure cut-over valve makes described twin-tub pumping installations in described low pressure pumping readiness.But at this, it should be noted that the switching of above-mentioned second step does not adopt the form of high/low pressure cut-over valve to realize certainly, the mode that in prior art, same existence is communicated with sebific duct by manual change realizes.Shown in Figure 1, for example, as a kind of common type, described high/low pressure cut-over valve can comprise six two-way plug-in valve C1, C2, C3, C4, C5, C6 and for the switching hydraulic control oil circuit selector valve 9(that controls these six two-way plug-in valve on off operating modes for example Fig. 1 should switch hydraulic control oil circuit selector valve 9 and adopted O type 3-position 4-way solenoid directional control valves, this typical high/low pressure cut-over valve form is described above, does not repeat them here).

Typically, the hydraulic control system of described twin-tub pumping installations can be open hydraulic control system, and as mentioned above, wherein said the first working oil path 7 and the second working oil path 8 are connected in described main oil-feed oil circuit 5 and main oil return circuit 6 via main reversing valve 3.In above-mentioned first step, by controlling described main reversing valve 3, described the first and second working oil path 7,8 are all ended with main oil-feed oil circuit 5 and main oil return circuit 6; In above-mentioned third step, by controlling described main reversing valve 3, described the first and second working oil path 7,8 are alternately communicated with one and the another one of described main oil-feed oil circuit 5 and main oil return circuit 6.For example, main reversing valve 3 can adopt the hyraulic controlled type O type three position four-way directional control valve shown in Fig. 1, should

Referring to Fig. 1, Fig. 2 and Fig. 4, as the another kind of form of implementation of high low pressure switching method of the present invention, its low pressure pump that is mainly used in twin-tub pumping installations is sent to high pressure pumping and switches, and particularly, the high low pressure switching method of this another kind form of implementation comprises the steps:

First, under state at described twin-tub pumping installations in low pressure pumpdown, make described the first and second working oil path 7,8 all end (making the first and second working oil path stop conveying liquid force feed) with described main oil-feed oil circuit 5 and main oil return circuit 6, to stop the low pressure pumpdown of described twin-tub pumping installations, thereby make this twin-tub pumping installations in the to be switched state of low pressure pumping, and keep the first scheduled time ta ' at the to be switched state of this low pressure pumping;

The second, make described the first and second master cylinders 1,2 rod chamber 1b separately, 2b is interconnected to form communicated cavity, and makes this communicated cavity with respect to described the first and second working oil path 7,8) all cut-offs; And the rodless cavity 1a of described the first master cylinder and the rodless cavity 2a of described the second master cylinder are relative to each other ended, and the rodless cavity 1a of this first master cylinder is communicated with described the first working oil path 7, the rodless cavity 2a of this second master cylinder is communicated with described the second working oil path 8, thereby make described twin-tub pumping installations in high pressure pumping readiness, and keep the second scheduled time tb ' at this high pressure pumping readiness;

The 3rd, make described the first and second working oil path 7,8 are alternately communicated with one and the another one of described main oil-feed oil circuit 5 and main oil return circuit 6, thereby by the first and second working oil path 7,8 make the rodless cavity 1a of described the first master cylinder and alternately oil-feed and oil return of the rodless cavity 2a of the second master cylinder, thereby make described twin-tub pumping installations in high pressure pumping job state.

Similar with above-mentioned form of implementation of the present invention, in the another kind of form of implementation of this high low pressure switching method, the above-mentioned high low pressure switching method key that makes twin-tub pumping installations be switched to high pressure pumping state from low pressure pumping state of the present invention is also to realize a kind of time-oriented sequential control, make to stop low pressure pumping, high pressure handover operation, and restart pumpdown and carry out according to predetermined sequential, this has been avoided in prior art when high low pressure switches simultaneously or has carried out disorderly a plurality of control actions, and for example, by keep certain buffer time (the first scheduled time ta ' and the second scheduled time tb ') after each operating procedure, after making the oil circuit of hydraulic control system stable, carry out again next step operation, this has alleviated the hydraulic shock in hydraulic control system effectively, make master cylinder stable working, and the hydraulic oil of having realized communicated cavity inner sealing is relatively stable in different handoff procedures, thereby make master cylinder drive stroke to keep constant relative efficiency.Similarly, in above-mentioned high low pressure switching method of the present invention, the time-oriented sequential control that has realized according to the order of sequence priority of each step, therefore above-mentioned the first scheduled time ta ' and the second scheduled time tb ' can be included as zero situation, typically, described the first scheduled time ta ' and the second scheduled time tb ' can be respectively 0-10s.

About determining of the first scheduled time ta ' and the second scheduled time tb ', more preferably, hydraulic control system at described twin-tub pumping installations is under the situation of open hydraulic control system, wherein said the first and second working oil path 7, 8 are connected in main oil-feed oil circuit 5 and main oil return circuit 6 via main reversing valve 3, in above-mentioned first step, when stopping the low pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit 5, low pressure pumping in the first working oil path 7 or the second working oil path stops oil pressure constantly, and according to this low pressure pumping, stop oil pressure constantly and determine the first scheduled time ta ' in described first step and the second scheduled time tb ' in described second step by inquiry experts database, or the hydraulic control system at described twin-tub pumping installations is under the situation of Closed Hydraulic control system, wherein said the first and second working oil path 7, 8 are connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, with by the positive and negative of described oil hydraulic pump then make described the first and second working oil path 7, one oil-feed in 8, another one oil return, in above-mentioned first step, the low pressure pumping detecting when stopping the low pressure pumpdown of described twin-tub pumping installations in described the first working oil path 7 or the second working oil path stops oil pressure constantly, and according to this low pressure pumping, stop oil pressure constantly and determine the first scheduled time ta ' in described first step and the second scheduled time tb ' in described second step by inquiry experts database, described experts database comprises that each low pressure pumping stops corresponding the first scheduled time value of oil pressure value and the second scheduled time value constantly.That is to say, this first scheduled time ta ' and the second scheduled time tb ' be corresponding the first predetermined hold-time and the second predetermined hold-time of employing the control procedure that is sent to high pressure pumping switching from low pressure pump for above-mentioned open type or Closed Hydraulic control system accordingly, and this all can be tested and be made experts database set up pointedly corresponding data corresponding relation for the different handoff procedures of the hydraulic control system of different types by simulated condition.

In addition, the relevant switching by height switching valve realizes high pressure pumping readiness and realizes the first and second working oil path 7,8 by main reversing valve 3 and replaces the state switchings such as oil inlet and oil return, similar with above-mentioned form of implementation, does not repeat them here.

The high low pressure switching method of the twin-tub pumping installations of above-mentioned first and second kinds of forms of implementation can be applicable to the high low pressure switching controls of various known twin-tub pumping installations at large, is especially applicable to the high low pressure switching controls of Concrete Double cylinder pumping installations (those skilled in the art are also referred to as " concrete pump ").

For helping skilled in the art to understand the high low pressure switching method of above-mentioned two kinds of forms of the present invention, below take a kind of twin-tub pumping installations of canonical form of Fig. 1 and hydraulic control system thereof and describe the specific operation process of high low pressure switching method of the present invention as example.In Fig. 1, main reversing valve 3 is hyraulic controlled type O type three position four-way directional control valve, and its hydraulic control linkage structure, hereinbefore to be described, is controlled guide's hydraulic control oil circuit to realize the selector valve of main reversing valve 3 by the pilot-actuated valve 14 of 3-position 4-way solenoid directional control valve form; High/low pressure cut-over valve adopts the canonical form that comprises six two-way plug-in valves, and the hydraulic control oil circuit of these six two-way plug-in valves is controlled by the switching hydraulic control oil circuit selector valve 9 of 3-position 4-way solenoid directional control valve form.Fig. 2 is that the twin-tub pumping installations shown in Fig. 1 is realized the sequential chart that high low pressure switches.Shown in Fig. 1 and Fig. 2, t0 to t1 constantly twin-tub pumping installations be high pressure pumping job state, the right side electromagnet YW2 that now switches hydraulic control oil circuit selector valve 9 obtains electric, left side electromagnet YW1 dead electricity; Main reversing valve 3 is alternately communicated with the first working oil path 7 and the second working oil path 8 at normal control Xia Shi winner's oil-feed oil circuit 5 and the main oil return circuit 6 of pilot-actuated valve 14.At t1 constantly, by controlling pilot-actuated valve 14, make main reversing valve 3 be switched to meta, be electromagnet YW3, the YW4 dead electricity of pilot-actuated valve 14 both sides, main reversing valve 3 switches back meta, high pressure pumpdown stops, and time delay is to the t2 moment (being the first above-mentioned scheduled delay ta=t2-t1).At t2 constantly, make to switch the right side electromagnet YW2 dead electricity of hydraulic control oil circuit selector valve 9, two-way plug-in valve C1, C5, C6 opens, make the left side electromagnet YW1 that switches hydraulic control oil circuit selector valve 9 obtain electric simultaneously, two-way plug-in valve C2, C3, C4 closes, thereby the first working oil path 7 is communicated with the rod chamber 1b of the first master cylinder 1, the second working oil path 8 is communicated with the rod chamber 2b of the second master cylinder 2, and the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 is interconnected, and all with respect to the first working oil path 7 and the second working oil path 8 cut-offs, thereby make twin-tub pumping installations switch to low pressure pumping readiness, downward up to the t3 moment (being above-mentioned the second scheduled delay tb=t3-t2) at this low pressure pumping state.At t3 constantly, by making both sides electromagnet YW3, the YW4 of pilot-actuated valve 14 replace electricly, thereby make main reversing valve 3 alternately be operated in left position and right position, twin-tub pumping installations carries out low pressure pumpdown.In addition, from low pressure pump, be sent to the situation of high pressure pumping switching, referring to Fig. 1 and Fig. 2, in the t1 ' moment before, twin-tub pumping installations is low pressure pumping job state, now switches the right side electromagnet YW2 dead electricity of hydraulic control oil circuit selector valve 9, and left side electromagnet YW1 obtains electric; Main reversing valve 3 is alternately communicated with the first working oil path 7 and the second working oil path 8 at normal control Xia Shi winner's oil-feed oil circuit 5 and the main oil return circuit 6 of pilot-actuated valve 14.At t1 ' constantly, by controlling pilot-actuated valve 14, make main reversing valve 3 be switched to meta, be electromagnet YW3, the YW4 dead electricity of pilot-actuated valve 14 both sides, main reversing valve 3 switches back meta, low pressure pumpdown stops, and time delay is to t2 ' (being first above-mentioned scheduled time ta '=t2 '-t1 ') constantly.At t2 ' constantly, make the right side electromagnet YW2 that switches hydraulic control oil circuit selector valve 9 obtain electric, two-way plug-in valve C1, C5, C6 locking, make to switch the left side electromagnet YW1 dead electricity of hydraulic control oil circuit selector valve 9 simultaneously, two-way plug-in valve C2, C3, C4 opens, thereby the first working oil path 7 is communicated with the rodless cavity 1a of the first master cylinder 1, the second working oil path 8 is communicated with the rodless cavity 2a of the second master cylinder 2, and the rod chamber 2b of the rod chamber 1b of the first master cylinder 1 and the second master cylinder 2 is interconnected, and all with respect to the first working oil path 7 and the second working oil path 8 cut-offs, thereby make twin-tub pumping installations switch to high pressure pumping readiness, downward up to t3 ' (being above-mentioned second scheduled time tb '=t3 '-t2 ') constantly at this high pressure pumping state.At t3 ' constantly, by making both sides electromagnet YW3, the YW4 of pilot-actuated valve 14 replace electricly, thereby make main reversing valve 3 alternately be operated in left position and right position, twin-tub pumping installations carries out high pressure pumpdown.

At this, it should be noted that; high low pressure switching method of the present invention is not limited to the twin-tub pumping installations shown in Fig. 1 and the concrete form of hydraulic control system thereof; there is in the prior art various forms in described high/low pressure cut-over valve, main reversing valve 3 etc.; no matter it adopts automatically controlled, hydraulic control, electric-hydraulic proportion to control; or adopt manually control etc.; as long as it adopted the technical conceive of time-oriented sequential control of the present invention, it all belongs to protection scope of the present invention.In addition, above-mentionedly take open type hydraulic system that main reversing valve 3 realizes the first working oil path 7 and the commutation of the second working oil path 8 and be described as example, but the present invention is not limited thereto, for example high low pressure switching method of the present invention is equally also applicable to turn to realize by changing oil hydraulic pump the closed system of commutation, in this case, the first working oil path 7 of twin-tub pumping installations and the second working oil path 8 form closed circuit via oil hydraulic pump, above-mentioned main oil-feed oil circuit and main oil return circuit can no longer arrange (considers leakage in practical application, the factors such as sealing, oil hydraulic pump is also connected with corresponding repairing oil circuit), in this case, during the first working oil path 7 oil-feed, backhaul hydraulic oil in the second working oil path 8 oil returns and the second working oil path 8 is delivered directly in the first working oil path 7 via oil hydraulic pump, when oil hydraulic pump change turns to, the first working oil path 7 oil returns, backhaul hydraulic oil in the second working oil path 8 oil-feeds and the first working oil path 7 is delivered directly in the second working oil path 8 via oil hydraulic pump, thereby alternately make the one oil-feed of the first working oil path 7 and the second working oil path 8, another one oil return simultaneously, thereby realize the alternately flexible of the first master cylinder 1 and the second master cylinder 2, these all belong to protection scope of the present invention.

By upper description, can be found out, the invention has the advantages that: high low pressure switching method of the present invention with respect to existing techniques in realizing accurate time-oriented sequential control, make to stop pumping, high low pressure handover operation, and restart pumpdown and carry out according to predetermined sequential, this has been avoided in prior art when high low pressure switches simultaneously or has carried out disorderly a plurality of control actions, and by keep certain buffer time after corresponding operating procedure, after making the oil circuit of hydraulic control system stable, carry out again next step operation, this has alleviated the hydraulic shock in hydraulic control system effectively, make master cylinder stable working, and in handoff procedure, make the hydraulic oil in communicated cavity relatively stable, thereby make master cylinder drive stroke to keep constant relative efficiency.The high low pressure that high low pressure switching method of the present invention can be applied to the twin-tub pumping installations of various existing forms at large switches, and it has general applicability and using value, and especially it can adopt automatically controlled form, thereby realize automatically, controls.

Especially, for example, when the hydraulic control system of twin-tub pumping installations adopts automatically controlled switch forms (the illustrative hydraulic control system of Fig. 1), high low pressure switching method of the present invention can be realized time-oriented sequential control mechanical, electrical, liquid one easily, and intelligence is convenient.That is to say, the present invention is according to the practical situation of the hydraulic system in twin-tub pumping installations high low pressure handoff procedure, reasonably control the sequential of cycle and taking corresponding operation in high low pressure handoff procedure, first pumping stops and time delay, carry out again high low pressure switching, after to be switched completing, restart pumping, thereby make hydraulic control system handoff procedure relatively steadily reliable.

Below describe by reference to the accompanying drawings the preferred embodiment of the present invention in detail; but; the present invention is not limited to the detail in above-mentioned mode of execution; within the scope of technical conceive of the present invention; can carry out multiple simple variant to technological scheme of the present invention, these simple variant all belong to protection scope of the present invention.

It should be noted that in addition each the concrete technical characteristics described in above-mentioned embodiment, in reconcilable situation, can combine by any suitable mode.For fear of unnecessary repetition, the present invention is to the explanation no longer separately of various possible compound modes.

In addition, between various mode of execution of the present invention, also can carry out combination in any, as long as it is without prejudice to thought of the present invention, it should be considered as content disclosed in this invention equally.

Claims

1. the high low pressure switching method of twin-tub pumping installations, the hydraulic control system of described twin-tub pumping installations comprises the first and second master cylinders (1 that are respectively used to this twin-tub pumping installations, 2) the first and second working oil path (7 of oil inlet and oil return, 8), this alternately oil-feed and oil return of the first and second working oil path (7,8), to realize described the first and second master cylinders (1,2) alternately stretch, is characterized in that, described high low pressure switching method comprises the steps:

First, under state at described twin-tub pumping installations in high pressure pumpdown, make described the first and second working oil path (7,8) stop conveying liquid force feed, to stop the high pressure pumpdown of described twin-tub pumping installations, thereby make this twin-tub pumping installations in the to be switched state of high pressure pumping, and keep the first scheduled delay ta at the to be switched state of this high pressure pumping;

The second, make described the first and second master cylinders (1,2) rodless cavity (1a, 2a) separately be interconnected to form communicated cavity, and this communicated cavity is all ended with respect to described the first and second working oil path (7,8); And the rod chamber (1b) of described the first master cylinder and the rod chamber (2b) of described the second master cylinder are relative to each other ended, and the rod chamber (1b) of this first master cylinder is communicated with described the first working oil path (7), the rod chamber of this second master cylinder (2b) is communicated with described the second working oil path (8), thereby make described twin-tub pumping installations in low pressure pumping readiness, and keep the second scheduled delay tb at this low pressure pumping readiness;

The 3rd, by described the first and second working oil path (7,8) make alternately oil-feed and the oil return of rod chamber (2b) of rod chamber (1b) and second master cylinder of described the first master cylinder, thereby make described twin-tub pumping installations in low pressure pumping job state.

2. the high low pressure switching method of twin-tub pumping installations according to claim 1, wherein, the hydraulic control system of described twin-tub pumping installations is open hydraulic control system, wherein said the first and second working oil path (7, 8) via main reversing valve (3), be connected in main oil-feed oil circuit (5) and main oil return circuit (6), in described first step, when stopping the high pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit (5), high pressure pumping in the first working oil path (7) or the second working oil path stops oil pressure constantly, and according to this high pressure pumping, stop oil pressure constantly and determine the first scheduled delay ta in described first step and the second scheduled delay tb in described second step by inquiry experts database, or

The hydraulic control system of described twin-tub pumping installations is Closed Hydraulic control system, wherein said the first and second working oil path (7, 8) be connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, with by the positive and negative of described oil hydraulic pump then make described the first and second working oil path (7, 8) the one oil-feed in, another one oil return, in described first step, the high pressure pumping detecting when stopping the high pressure pumpdown of described twin-tub pumping installations in described the first working oil path (7) or the second working oil path stops oil pressure constantly, and according to this high pressure pumping, stop oil pressure constantly and determine the first scheduled delay ta in described first step and the second scheduled delay tb in described second step by inquiry experts database,

Described experts database comprises that each high pressure pumping stops corresponding the first scheduled delay value of oil pressure value and the second scheduled delay value constantly.

3. the high low pressure switching method of twin-tub pumping installations according to claim 1, wherein, described the first scheduled delay ta and the second scheduled delay tb are respectively 0-10s.

4. the high low pressure switching method of twin-tub pumping installations according to claim 1, wherein, described the first and second working oil path (7,8) via high/low pressure cut-over valve, be connected in described the first and second master cylinders (1 respectively, 2), in described second step, the switching by described high/low pressure cut-over valve makes described twin-tub pumping installations in described low pressure pumping readiness.

5. the high low pressure switching method of twin-tub pumping installations according to claim 1, wherein, the hydraulic control system of described twin-tub pumping installations is open hydraulic control system, wherein said the first and second working oil path (7,8) are connected in main oil-feed oil circuit (5) and main oil return circuit (6) via main reversing valve (3); In described first step, by controlling described main reversing valve (3), make described the first and second working oil path (7,8) all end with described main oil-feed oil circuit (5) and main oil return circuit (6), thereby make this first and second working oil path (7,8) stop conveying liquid force feed; In described third step, by controlling described main reversing valve (3), make described the first and second working oil path (7,8) be alternately communicated with one and the another one of described main oil-feed oil circuit (5) and main oil return circuit (6), thereby by described the first and second working oil path (7,8), make alternately oil-feed and the oil return of rod chamber (2b) of rod chamber (1b) and second master cylinder of described the first master cylinder.

6. the high low pressure switching method of twin-tub pumping installations according to claim 5, wherein, described main reversing valve (3) is O type three position four-way directional control valve.

7. according to the high low pressure switching method of the twin-tub pumping installations described in any one in claim 1 to 6, wherein, described twin-tub pumping installations is Concrete Double cylinder pumping installations.

8. the high low pressure switching method of twin-tub pumping installations, the hydraulic control system of described twin-tub pumping installations comprises the first and second master cylinders (1 that are respectively used to this twin-tub pumping installations, 2) the first and second working oil path (7 of oil inlet and oil return, 8), this alternately oil-feed and oil return of the first and second working oil path (7,8), to realize described the first and second master cylinders (1,2) alternately stretch, is characterized in that, described high low pressure switching method comprises the steps:

First, under state at described twin-tub pumping installations in low pressure pumpdown, make described the first and second working oil path (7,8) stop conveying liquid force feed, to stop the low pressure pumpdown of described twin-tub pumping installations, thereby make this twin-tub pumping installations in the to be switched state of low pressure pumping, and keep the first scheduled time ta ' at the to be switched state of this low pressure pumping;

The second, make described the first and second master cylinders (1,2) rod chamber (1b, 2b) separately be interconnected to form communicated cavity, and this communicated cavity is all ended with respect to described the first and second working oil path (7,8); And the rodless cavity (1a) of described the first master cylinder and the rodless cavity (2a) of described the second master cylinder are relative to each other ended, and the rodless cavity (1a) of this first master cylinder is communicated with described the first working oil path (7), the rodless cavity of this second master cylinder (2a) is communicated with described the second working oil path (8), thereby make described twin-tub pumping installations in high pressure pumping readiness, and keep the second scheduled time tb ' at this high pressure pumping readiness;

The 3rd, by described the first and second working oil path (7,8) make alternately oil-feed and the oil return of rodless cavity (2a) of rodless cavity (1a) and second master cylinder of described the first master cylinder, thereby make described twin-tub pumping installations in high pressure pumping job state.

9. the high low pressure switching method of twin-tub pumping installations according to claim 8, wherein, the hydraulic control system of described twin-tub pumping installations is open hydraulic control system, wherein said the first and second working oil path (7, 8) via main reversing valve (3), be connected in main oil-feed oil circuit (5) and main oil return circuit (6), in described first step, when stopping the low pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit (5), low pressure pumping in the first working oil path (7) or the second working oil path stops oil pressure constantly, and according to this low pressure pumping, stop oil pressure constantly and determine the first scheduled time ta ' in described first step and the second scheduled time tb ' in described second step by inquiry experts database, or

The hydraulic control system of described twin-tub pumping installations is Closed Hydraulic control system, wherein said the first and second working oil path (7, 8) be connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, with by the positive and negative of described oil hydraulic pump then make described the first and second working oil path (7, 8) the one oil-feed in, another one oil return, in described first step, the low pressure pumping detecting when stopping the low pressure pumpdown of described twin-tub pumping installations in described the first working oil path (7) or the second working oil path stops oil pressure constantly, and according to this low pressure pumping, stop oil pressure constantly and determine the first scheduled time ta ' in described first step and the second scheduled time tb ' in described second step by inquiry experts database,

Described experts database comprises that each low pressure pumping stops corresponding the first scheduled time value of oil pressure value and the second scheduled time value constantly.

10. the high low pressure switching method of twin-tub pumping installations according to claim 8, wherein, described the first scheduled time ta ' and the second scheduled time tb ' are respectively 0-10s.

The high low pressure switching method of 11. twin-tub pumping installations according to claim 8, wherein, described the first and second working oil path (7,8) via high/low pressure cut-over valve, be connected in described the first and second master cylinders (1 respectively, 2), in described second step, the switching by described high/low pressure cut-over valve makes described twin-tub pumping installations in described high pressure pumping readiness.

The high low pressure switching method of 12. twin-tub pumping installations according to claim 8, wherein, the hydraulic control system of described twin-tub pumping installations is open hydraulic control system, wherein said the first and second working oil path (7,8) are connected in main oil-feed oil circuit (5) and main oil return circuit (6) via main reversing valve (3); In described first step, by controlling described main reversing valve (3), make described the first and second working oil path (7,8) all end with described main oil-feed oil circuit (5) and main oil return circuit (6), thereby make this first and second working oil path (7,8) stop conveying liquid force feed; In described third step, by controlling described main reversing valve (3), make described the first and second working oil path (7,8) be alternately communicated with one and the another one of described main oil-feed oil circuit (5) and main oil return circuit (6), thereby by described the first and second working oil path (7,8), make alternately oil-feed and the oil return of rodless cavity (2a) of rodless cavity (1a) and second master cylinder of described the first master cylinder.

The high low pressure switching method of 13. twin-tub pumping installations according to claim 12, wherein, described main reversing valve (3) is O type three position four-way directional control valve.

The high low pressure switching method of the twin-tub pumping installations in 14. according to Claim 8 to 13 described in any one, wherein, described twin-tub pumping installations is Concrete Double cylinder pumping installations.

The hydraulic control system of 15. twin-tub pumping installations, comprise automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity (1a) of the first master cylinder (1) and rodless cavity (2a) and the rod chamber (2b) of rod chamber (1b) and the second master cylinder (2) of described twin-tub pumping installations by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path (7) and the second working oil path (8), this first working oil path (7) and the second working oil path (8) are connected in main oil-feed oil circuit (5) and main oil return circuit (6) by the main reversing valve (3) of electric control reversing valve form, it is characterized in that, described hydraulic control system also comprises controller, this controller is electrically connected on described main reversing valve (3) and automatically controlled high/low pressure cut-over valve, described controller is used for receiving operational order so that described twin-tub pumping installations is switched to low pressure pumping or is switched to high pressure pumping from low pressure pumping from high pressure pumping, and this controller is controlled according to following sequential: first, control described main reversing valve (3) and stop the current pumpdown carrying out, and keep pumpdown halted state the first predetermined hold-time, the second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and after high low pressure state switches, keep the second predetermined hold-time, the 3rd, control described main reversing valve so that described twin-tub pumping installations carries out pumpdown.

The hydraulic control system of 16. twin-tub pumping installations according to claim 15, wherein, described main oil-feed oil circuit (5), in the first working oil path (7) or the second working oil path (8), be provided with oil pressure detection device (4), this oil pressure detection device (4) is electrically connected on described controller so that the fuel injection pressure signal of detection is transferred to this controller, the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to described oil pressure detection device stops fuel injection pressure signal constantly and determines described the first predetermined hold-time and the second predetermined hold-time by inquiry experts database, described experts database is stored in described controller or in external server, this experts database comprises that each pumping stops corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value constantly.

The hydraulic control system of 17. twin-tub pumping installations, comprise automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity (1a) of the first master cylinder (1) and rodless cavity (2a) and the rod chamber (2b) of rod chamber (1b) and the second master cylinder (2) of described twin-tub pumping installations by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path (7) and the second working oil path (8), it is characterized in that, this first working oil path (7) and the second working oil path (8) are connected in the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, with by the positive and negative of described oil hydraulic pump then make described the first and second working oil path (7, 8) the one oil-feed in, another one oil return, wherein, described hydraulic control system also comprises controller, this controller is electrically connected on automatically controlled rotating driving device and the automatically controlled high/low pressure cut-over valve of described oil hydraulic pump, described controller is used for receiving operational order so that described twin-tub pumping installations is switched to low pressure pumping or is switched to high pressure pumping from low pressure pumping from high pressure pumping, and this controller is controlled according to following sequential: first, control the automatically controlled rotating driving device of described oil hydraulic pump to stop the current pumpdown carrying out, and keep pumpdown halted state the first predetermined hold-time, the second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and after high low pressure state switches, keep the second predetermined hold-time, the 3rd, control the automatically controlled rotary actuation of described oil hydraulic pump so that described twin-tub pumping installations carries out pumpdown.

The hydraulic control system of 18. twin-tub pumping installations according to claim 17, wherein, in described the first working oil path (7) or the second working oil path (8), be provided with oil pressure detection device (4), this oil pressure detection device (4) is electrically connected on described controller so that the fuel injection pressure signal of detection is transferred to this controller, the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to described oil pressure detection device stops fuel injection pressure signal constantly and determines described the first predetermined hold-time and the second predetermined hold-time by inquiry experts database, described experts database is stored in described controller or in external server, this experts database comprises that each pumping stops corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value constantly.

19. pumping equipments, comprise the hydraulic control system of twin-tub pumping installations and this twin-tub pumping installations, and wherein, described hydraulic control system is according to claim 15 to the hydraulic control system described in any one in 18.