A kind of fracturing pump of hydraulic-driven
Technical field
The present invention relates to oil gas fracturing technique field, in particular to a kind of fracturing pump of hydraulic-driven.
Background technique
Pressing crack construction operation is transformation one of the important means of oil-gas reservoir, for low permeability oil and gas well, generally require by
Fracturing work can be only achieved the purpose of stable yields and volume increase.Fracturing pump is the working host of fracturing unit truck, is to realize that fracturing technology is intended to
Equipment is most directly executed, is mainly made of the components such as power end assembly and fluid end assembly.
In the prior art, crank type plunger pump is generally used as the fracturing pump of conveying mechanism, Fig. 4 is this crank type column
The structural schematic diagram for filling in pump, as shown in figure 4, crank type plunger pump 1' includes crankshaft 11', multiple connecting rod 12' and multiple plungers
13' etc., the both ends of crankshaft 11' are provided with power input gear, and multiple plunger 13' are arranged in the side of crankshaft 11', multiple plungers
One end of 13' can move back and forth in fluid end (show in figure but do not mark) respectively, and multiple connecting rod 12' are arranged in multiple plungers
Between the other end and crankshaft 11' of 13', in this way when crankshaft 11' is rotated, connecting rod 12' will be driven to make crank rod movement, connecting rod
12' drives plunger 13' reciprocating (similar to the movement of engine crankshaft and piston) in turn, passes through fluid end to realize
By working media (fracturing fluid) sucking and continuous High voltage output, to carry out fracturing work.
In above-mentioned crank type plunger pump, stroke is shorter (such as five cylinder formula plunger pumps stroke are about 200mm), commutates often,
Plunger action is frequent, and the service life of vulnerable part is short, for example, the service life of the valve seat of fluid end, valve and valve rubber etc. only has tens
Hour;In addition, the output pressure of this crank type plunger pump, the coverage area of flow are relatively narrow, to improve coverage area, need more
Change the fluid end of different cylinder diameters;In addition, plunger, in frequently quickly commutation, not yet sufficiently sucking is discharged fracturing fluid, cause to inhale
Enter inefficient, causes working efficiency relatively low;In addition, integrated installation has crankshaft, power input gear, connecting rod, liquid in fracturing pump
The cabinet and pedestal at power end etc., structure is complicated, and manufacturing cost is high, and dismounting maintenance is inconvenient;In addition, power input gear makees high speed weight
Carry rotation, it is high to lubrication and cooling requirement, need arragement construction complexity lubricating system and corresponding cooling system.
Therefore, how to be improved for existing above-mentioned insufficient and defect, more to adapt to oil and gas development needs, be
Those skilled in the art's technical problem urgently to be resolved.
Summary of the invention
(1) technical problems to be solved
It is an object of the invention to overcome the defect in the prior art, one kind is provided and effectively increases stroke, reduce jig frequency, is mentioned
The service life of high vulnerable part, the effectively coverage area of increase output pressure, flow, effectively improve suction efficiency, are effectively reduced
Structural complexity, save the cost, and the requirement of lubrication and cooling is effectively reduced, it may not need automatically controlled control, the liquid of low noise
Press the fracturing pump of driving.
(2) technical solution
To achieve the above object, the present invention provides a kind of fracturing pumps of hydraulic-driven, are provided with oil inlet P, oil return opening
T, inlet V and high pressure liquid outlet H, which is characterized in that including pressurized cylinder and pilot-operated type pilot operated directional control valve;
The pressurized cylinder includes low pressure (LP) cylinder, low-pressure piston, left high-pressure plunger, right high-pressure plunger, left high pressure cylinder and right high pressure
Cylinder, the low-pressure piston are slidably arranged in low pressure (LP) cylinder and are respectively formed with left piston chamber and right piston chamber in its left and right ends,
Its left and right ends is connected with the right high-pressure plunger being slidably arranged in the left high-pressure plunger and right high pressure cylinder in left high pressure cylinder respectively;
When low-pressure piston moves left to it and the first through-flow slot is completely covered by position, low-pressure piston passes through closed left piston chamber system
It is dynamic;The left and right ends of low pressure (LP) cylinder are additionally provided with the first through-flow slot and the second through-flow slot, and it is through-flow by second to be shifted to the right to it in low-pressure piston
When slot is completely covered by position, low-pressure piston is braked by closed right piston chamber;
The pilot-operated type pilot operated directional control valve is provided with oil inlet runner, oil return runner, the first actuator port A and the second working oil
Mouth B, the oil inlet runner are connected with oil inlet P, and the oil return runner is connected with the oil return inlet T;First work
Hydraulic fluid port A is divided into two-way, is connected all the way by the first through-flow slot with left piston chamber, and another way is by the first connection check valve through a left side
The right side of high pressure cylinder is connected with left piston chamber;The second actuator port B is divided into two-way, all the way by the second through-flow slot with
Right piston chamber is connected, and another way is connected behind the left side of right high pressure cylinder with right piston chamber by the second connection check valve;
The pilot-operated type pilot operated directional control valve includes pilot valve, main valve, the first overflow valve and the second overflow valve, the pilot valve
For two position three way directional control valve, the main valve is two-position four way change valve, the oil inlet P 1 of the main valve and the oil inlet of pilot valve
P2 is connected with oil inlet runner, and the oil return inlet T 1 of the main valve is connected with oil return runner, the actuator port A1 of the main valve
It is connected with the first actuator port A, the actuator port A2 of the main valve is connected with the second actuator port B, the pilot valve
Actuator port A2 is connected with the left control chamber of main valve, and the left control chamber of the main valve also passes through the 4th damping hole and oil return runner
It communicates, the actuator port B2 of the pilot valve is connected with the right control chamber of main valve, and the right control chamber of the main valve also passes through
Three damping holes are communicated with oil return runner;The first port of first overflow valve is connected and described with the first actuator port A
The second port of first overflow valve is connected with the left first guide cavity, the first port and the second actuator port of second overflow valve
B is connected and the second port of second overflow valve is connected with the right first guide cavity, and the left first guide cavity of the pilot valve also passes through
First damping hole is connected with oil return runner, and the right first guide cavity of the pilot valve also passes through the second damping hole and is connected with oil return runner
It is logical.
Through the above technical solutions, moving to left and right ends when the pressure break pump work by low-pressure piston and being completely covered by
Low-pressure piston is braked when the first through-flow slot or the second through-flow groove location, while triggering the first overflow valve or the second overflow valve
Unlatching triggers the pilot valve of pilot-operated type pilot operated directional control valve, and pilot valve is made first to commutate, then is controlled and led by pilot valve
Valve commutates, and can guarantee to start when low-pressure piston toward when opposite direction movement in this way, the displacement of main valve and low-pressure piston is not
It can influence each other, and pilot valve changes the flow very little gone backward through in main valve, can reliably be maintained at commutation position, therefore this hair
It is bright that sucking and pressurization discharge circulation to fracturing fluid can be realized without automatically controlled control, without crankshaft, power input gear, company
Bar, lubricating system and cooling system, components are few, structure is simple, at low cost;In addition, because low-pressure piston and left and right high-pressure column
Plug is all low-speed rectilinear movement, and long stroke may be implemented, thus improve effective suction efficiency, reduce jig frequency and improve the service life, and
Low-pressure piston moves back and forth the primary imbibition that can be achieved twice and pressurization discharge, no-idle running, high-efficient;Additionally by setting the
One through-flow slot and the second through-flow slot, lead to the first through-flow slot and second when both ends move to certain position to low-pressure piston to the left and right
Chute covers, and cuts off oil liquid flow pass, is braked, can be prevented low using completely enclosed left piston chamber and right piston chamber
The collision of piston and left high pressure cylinder and right high pressure cylinder is pressed, therefore impact noise will not be generated.
In further technical solution, when the main valve of the pilot-operated type pilot operated directional control valve is in left position, the oil inlet P 1
It is connected with actuator port B1, the actuator port A1 is connected with the oil return inlet T 1;It is described when the main valve is in right position
Actuator port P1 is connected with actuator port A1, and the actuator port B1 is connected with the oil return inlet T 1.
In further technical solution, when the pilot valve of the pilot-operated type pilot operated directional control valve is in left position, the oil inlet
P2 is connected with actuator port A2;When the pilot valve is in right position, the oil inlet P 2 is connected with actuator port B2.
In further technical solution, the left high pressure cylinder and right high pressure cylinder pass through first respectively and go out liquid check valve and second
Liquid check valve is connected to high pressure liquid outlet H out, and inlet V passes through the first feed liquor check valve and the second feed liquor check valve and a left side respectively
High pressure cylinder is connected to right high pressure cylinder.
It is described when low-pressure piston moves left to it and the first through-flow slot is completely covered by position in further technical solution
Low-pressure piston left side is greater than 20mm apart from low pressure (LP) cylinder left end distance;It is shifted to the right in low-pressure piston, and the second through-flow slot is complete
When covering position, the low-pressure piston right side is greater than 20mm apart from low pressure (LP) cylinder right end distance.Because of low-pressure piston and low pressure
Cylinder inner hole is interstitial fluid sealing cooperation, in order to guarantee when low-pressure piston has covered in the first through-flow slot and the second through-flow slot,
Will not continue the gap outflow between low-pressure piston and low pressure (LP) cylinder inner hole because of oil liquid causes low-pressure piston to continue to move and make
Fail at braking, enough seal lengths is needed, so distance of the low-pressure piston apart from both ends of the surface is at least more than 20mm.
In further technical solution, the is also connected between the oil inlet runner and the oil inlet P 2 of the pilot valve
Five damping holes.By the way that the 5th damping hole is arranged, more steady, the no impact of main valve commutation of pilot-operated type pilot operated directional control valve can be made.
(3) beneficial effect
Compared with prior art, technical solution of the present invention has the advantage that
When the pressure break pump work, left and right ends are moved to by low-pressure piston and are completely covered by the first through-flow slot or second logical
The first overflow valve is triggered when chute position or the second overflow valve is opened, to touch to the pilot valve of pilot-operated type pilot operated directional control valve
Hair, makes pilot valve first commutate, then commutate by pilot valve control bound, can guarantee to start when low-pressure piston in this way
Toward when opposite direction movement, the displacement of main valve and low-pressure piston will not influence each other, and pilot valve is changed in main valve and gone backward through
Flow very little can reliably be maintained at commutation position, therefore the present invention only needs to be connected with hydraulic pump, without complicated automatically controlled control
System can realize pressurization and sucking cyclic process to fracturing fluid, and low-pressure piston moves back and forth once, it can be achieved that pressure
The sucking twice and pressurization discharge process of liquid are split, it is no-idle running, high-efficient, without crankshaft, power input gear, connecting rod, profit
Sliding system and cooling system, structure are simple, at low cost;In addition, because low pressure (LP) cylinder and left and right high pressure cylinder are all low-speed rectilinear movement,
Long stroke may be implemented, to improve effective suction efficiency, reduce jig frequency and improve the service life;Additionally by the first through-flow slot of setting
With the second through-flow slot, the first through-flow slot and the second through-flow slot are hidden when both ends move to certain position to low-pressure piston to the left and right
Lid is cut off oil liquid flow pass, is braked using completely enclosed left piston chamber and right piston chamber, can prevent low-pressure piston
With the collision of left high pressure cylinder and right high pressure cylinder, therefore impact noise will not be generated.
Detailed description of the invention
Fig. 1 is the hydraulic schematic diagram (low-pressure piston state in an intermediate position) of the embodiment of the present invention;
Fig. 2 is the hydraulic schematic diagram (low-pressure piston by right lateral turn left row state) of the embodiment of the present invention;
Fig. 3 is the hydraulic schematic diagram (low-pressure piston by left lateral turn right row state) of the embodiment of the present invention;
Fig. 4 is the structural schematic diagram of typical crank type plunger pump in the prior art.
Specific embodiment
Fig. 1-3 is please referred to, is currently preferred one embodiment, the present invention provides a kind of fracturing pump of hydraulic-driven,
It is provided with oil inlet P, oil return inlet T, inlet V, high pressure liquid outlet H comprising pressurized cylinder and pilot-operated type pilot operated directional control valve;Pressurization
Cylinder includes low pressure (LP) cylinder 4, low-pressure piston 6, left high-pressure plunger 5b, right high-pressure plunger 5a, left high pressure cylinder 3b and right high pressure cylinder 3a, low pressure
Piston 6 is slidably arranged in low pressure (LP) cylinder 4 and is respectively formed with left piston chamber 4b and right piston chamber 4a, left and right in its left and right ends
Both ends respectively with the right high-pressure plunger 5a phase that is slidably arranged in the left high-pressure plunger 5b and right high pressure cylinder 3a in left high pressure cylinder 3b
Even;The left and right ends of low low pressure (LP) cylinder 4 are additionally provided with the first through-flow through-flow slot 4c of slot 4d and second, and moving left to it in low-pressure piston 6 will
When first through-flow slot 4d is completely covered by position, low-pressure piston 6 is braked by closed left piston chamber 4b;In low-pressure piston 6
When being shifted to the right to it the second through-flow slot 4c being completely covered by position, low-pressure piston 6 is braked by closed right piston chamber 4a.It can
With understanding, closed left piston chamber 4b refers to after the first through-flow slot 4d is completely covered by by low-pressure piston 6, left piston chamber 4b
Connection with the first actuator port A is cut off, and the oil liquid in left piston chamber 4b can neither return the first work by the first through-flow slot 4d
Make hydraulic fluid port A, the first actuator port A can not be returned by the first connection check valve 11b reversely ended, in addition in this position low pressure
The left side of piston 6 will also have a certain distance that could form cavity (left piston chamber 4b) with the left end of low pressure (LP) cylinder 4 certainly;Together
It manages closed right piston chamber 4a to refer to after the second through-flow slot 4c is completely covered by by low-pressure piston 6, right piston chamber 4a and the second work
The connection for making hydraulic fluid port B is cut off, and the oil liquid in right piston chamber 4a can neither return the second actuator port B by the second through-flow slot 4c,
The second actuator port B can not be returned by the second connection check valve 11a reversely ended, in addition in this position low-pressure piston 6
Right side will also have a certain distance that could form cavity (right piston chamber 4a) with the right end of low pressure (LP) cylinder 4 certainly.
Pilot-operated type pilot operated directional control valve is provided with oil inlet runner 14, oil return runner 15, the first actuator port A and the second working oil
Mouth B, oil inlet runner 14 are connected with oil inlet P, and oil return runner 15 is connected with oil return inlet T;First actuator port A is divided into two
Road is connected by the first through-flow slot 4d with left piston chamber 4b all the way, and another way is by the first connection check valve 11b through left high pressure
The right side of cylinder 3b is connected with left piston chamber 4b;Second actuator port B is divided into two-way, passes through the second through-flow slot 4c and the right side all the way
Plunger shaft 4a is connected, another way by second connection check valve 11a behind the left side of right high pressure cylinder 3a with right piston chamber 4a
It is connected;
Pilot-operated type pilot operated directional control valve includes pilot valve 8, main valve 9, the first overflow valve 7a and the second overflow valve 7b, pilot valve 8
For two position three way directional control valve, main valve 9 is two-position four way change valve, the oil inlet P 2 of the oil inlet P 1 of main valve 9 and pilot valve 8 all with
Oil inlet runner 14 is connected, and the oil return inlet T 1 of main valve 9 is connected with oil return runner 15, the actuator port A1 and the first work of main valve 12
Make hydraulic fluid port A to be connected, the actuator port A2 of main valve 12 is connected with the second actuator port B, the actuator port A2 of pilot valve 8 and master
The left control chamber 9b of valve 12 is connected, and the left control chamber 9b of main valve 12 also passes through the 4th damping hole 10b and communicates with oil return runner 15,
The actuator port B2 of pilot valve 8 is connected with the right control chamber 9a of main valve 9, and the right control chamber 9a of main valve 9 is also damped by third
Hole 10a is communicated with oil return runner 15;The first port of first overflow valve 7a is connected with the first actuator port A and the first overflow valve 7a
Second port be connected with left elder generation guide cavity 8b, the first port of the second overflow valve 7b be connected with the second actuator port B and second overflow
The second port of stream valve 7b is connected with right elder generation guide cavity 8a, and the left elder generation guide cavity 8b of pilot valve 8 also passes through the first damping hole 12b and oil return
Runner 15 is connected, and the right elder generation guide cavity 8a of pilot valve 8 also passes through the second damping hole 12a and is connected with oil return runner 15.
When the main valve 9 of pilot-operated type pilot operated directional control valve is in left position, the oil inlet P 1 is connected with actuator port B1, described
Actuator port A1 is connected with the oil return inlet T 1;When main valve 9 is in right position, the actuator port P1 is connected with actuator port A1
Logical, the actuator port B1 is connected with the oil return inlet T 1.
When the pilot valve 8 of pilot-operated type pilot operated directional control valve is in left position, oil inlet P 2 is connected with actuator port A2;Pilot valve
8 be in right position when, oil inlet P 2 is connected with actuator port B2.
Left high pressure cylinder 3b and right high pressure cylinder 3a passes through first respectively and goes out liquid check valve 2b and second liquid check valve 2a and height out
Press juice mouth H connection, inlet V pass through respectively the first feed liquor check valve 1b and the second feed liquor check valve 1a and left high pressure cylinder 3b and
Right high pressure cylinder 3a connection.
When low-pressure piston 6 moves left to it and the first through-flow slot 4d is completely covered by position, 6 left side of low-pressure piston is apart from low
Cylinder pressure 4 left end distance is greater than 20mm;When low-pressure piston 6 is shifted to the right to it and the second through-flow slot 4c is completely covered by position, low pressure
6 right side of piston is greater than 20mm apart from 4 right end of low pressure (LP) cylinder distance.Because low-pressure piston 6 is that interstitial fluid is close with 4 inner hole of low pressure (LP) cylinder
Envelope cooperation will not be because of oil liquid in order to guarantee when low-pressure piston 6 has covered in the through-flow slot 4c of the first through-flow slot 4d and second
Continue that low-pressure piston 6 is caused to continue to move and braking is caused to lose from the gap outflow between 4 inner hole of low-pressure piston 6 and low pressure (LP) cylinder
It loses, so distance of the low-pressure piston 6 apart from both ends of the surface is at least more than 20mm.
Working principle of the present invention is as follows:
Using when oil inlet P of the invention is connected with hydraulic pump outlet, oil return inlet T is connected with fuel tank, inlet V and pressure
It splits liquid input channel to be connected, high pressure liquid outlet H is connected with fracturing fluid output channel.Assuming that 9 initial position of main valve is in right position, such as
Shown in Fig. 2, then oil inlet P 1 is connected with actuator port A1, and actuator port B1 is connected with oil return inlet T 1, one side oil liquid by
Oil inlet P after main valve 9, the first actuator port A by first connection check valve 11b enter left piston chamber 4b push piston 6 to
It moves right, another aspect fracturing fluid enters left high pressure cylinder 3b through the first feed liquor check valve 1b and carries out filling liquid, the oil of right piston chamber 4a
Liquid returns to fuel tank, right pressurization through the second through-flow slot 4c, the second actuator port B, actuator port B1, oil return inlet T 1, oil return runner 15
Fracturing fluid in cylinder 3a goes out liquid check valve 2a by second after being pressurized and reaches high pressure liquid outlet H.When piston 6 is moved right
When two-way chute 4c is completely covered by (as shown in Figure 2), the oil liquid of right piston chamber 4a cannot be discharged by the second through-flow slot 4c again, piston
6 can brake under the action of closed right piston chamber 4a, and the pressure of the first actuator port A can rise rapidly the first overflow of triggering
Valve 7a is opened, and oil liquid enters left first guide cavity 8b after the first overflow valve 7a is opened, and is set up pressure in left elder generation guide cavity 8b and is pushed guide
Valve 8 commutates to left position, and the oil liquid of right elder generation guide cavity 8a all reaches oil return inlet T after the second damping hole 12a, oil return runner 15, at this time
Oil inlet P 2 is connected with actuator port A2, and the oil liquid of oil inlet P enters the left control of main valve 12 through oil inlet P 2, actuator port A2
Chamber 9b control bound 9 processed commutates to left position, and the oil liquid of right control chamber 9a flows into oil return runner 15 by third damping hole 10a;Main valve 9
After commutating to left position, hydraulic pump outlet oil liquid connects through oil inlet P, oil inlet P 1, actuator port B1, the second actuator port B, second
Entering right piston chamber 4a after logical check valve 11a, (meanwhile the fracturing fluid liquid of inlet V enters right increasing through the second feed liquor check valve 1a
Cylinder pressure 3a carries out filling liquid) push low-pressure piston 6 to move downward, the oil liquid in left piston chamber 4b is through the first through-flow slot 4d, the first work
Oil return inlet T is reached after making hydraulic fluid port A, actuator port A1, oil return inlet T 1, oil return runner 15, the fracturing fluid in left high pressure cylinder 3b is through increasing
Go out liquid check valve 2b by first after pressure and be discharged to high pressure liquid outlet H, hides the first through-flow slot 4d completely when piston 6 moves downward
When lid position (as shown in Figure 3), the oil liquid in left piston chamber 4b cannot be discharged by the first through-flow slot 4d again, and piston 6 can closed
Left piston chamber 4b under the action of brake, the pressure of the second actuator port B can rise rapidly the second overflow valve 7b of triggering and open, the
Oil liquid enters right first guide cavity 8a after two overflow valve 7b are opened, and sets up pressure in right elder generation guide cavity 8a and pilot valve 8 is pushed to commutate to the right side
The oil liquid of position, left elder generation guide cavity 8b all reaches oil return inlet T after the first damping hole 12b, oil return runner 15, when pilot valve 13 commutates to
Behind right position, main valve 9 commutates to right position by the control of pilot valve 8, and the oil liquid of oil inlet P is through oil inlet P 1, the first actuator port A, the
One connection check valve 11b enters left piston chamber 4b, pushes piston 6 to move right pressurization, so far completes circulation.As long as oil inlet P
There is oil liquid persistently to supply, the cyclic process that fracturing pump of the invention will move back and forth and carry out filling liquid, be pressurized drain.
It is only the preferred embodiment of the present invention described in top, it is noted that for the ordinary skill people of the art
For member, without departing from the technical principles of the invention, several improvements and modifications can also be made, these improvements and modifications
Also it should be regarded as protection scope of the present invention.