A plunger type fracturing pump with a protective structure

Abstract

The present invention relates to the technical field of fracturing pumps, and in particular to a plunger-type fracturing pump with a protective structure. The present invention comprises: a power assembly, wherein the power assembly is fixedly connected to a pump body, wherein a hydraulic chamber is arranged in the pump body, and wherein a plunger is arranged in the power assembly; a first sealing group, which is installed in the hydraulic chamber of the pump body, and wherein the first sealing group is sealingly and slidingly connected to the plunger; a sealing member, which is slidingly connected to the side of the plunger away from the hydraulic chamber, and wherein a second sealing group and a third sealing group are installed on the sealing member. The present invention uses two sets of sealing structures, namely, the first sealing group and the second sealing group and the third sealing group, to jointly complete the sealing task. When the first sealing group is operating normally, the unnecessary wear of the second sealing group is reduced. When the first sealing group leaks, the second sealing group and the third sealing group replace the first sealing group for sealing, thereby increasing the continuous use time of the device and reducing the probability of unplanned downtime.

Description

Technical Field

[0001] The present invention relates to the technical field of fracturing pumps, and in particular to a plunger type fracturing pump with a protective structure. Background Art

[0002] The plunger fracturing pump is one of the core equipment for oil and gas field operations. The core structure of the plunger fracturing pump consists of a power end and a hydraulic end. The power end converts the rotational motion of the engine into the reciprocating motion of the plunger, and the hydraulic end extracts the fracturing fluid through the periodic reciprocating motion of the plunger in the hydraulic chamber, accumulates pressure in the fracturing fluid and discharges the high-pressure fracturing fluid outward. During the use of the existing plunger fracturing pump, the sealing components at the plunger are subjected to the friction of the plunger movement for a long time, and the fracturing fluid usually contains some corrosive chemicals, which causes the sealing components at the plunger to wear quickly. It is difficult to maintain high-intensity operations for a long time, resulting in the need for frequent shutdown maintenance of existing plunger-type fracturing pumps, making it difficult to speed up the progress of engineering operations. When the interval between two adjacent shutdown maintenance is long, the risk of leakage of the sealing component at the plunger will gradually increase over time. When the sealing component at the plunger leaks, the fracturing fluid will spray out through the leak, making it difficult to maintain a high-pressure environment inside the fracturing pump. The internal pressure of the fracturing pump decreases, and problems such as reduced pump efficiency and reduced output pressure occur, leading to unplanned shutdowns and serious delays in the progress of engineering operations. Summary of the invention

[0003] In order to overcome the shortcomings of the existing plunger-type fracturing pump, that is, the sealing assembly at the plunger wears quickly and is prone to leakage, the present invention provides a plunger-type fracturing pump with a protective structure.

[0004] The technical solution of the present invention is: a plunger-type fracturing pump with a protective structure, comprising: a power assembly, the power assembly is fixedly connected to a pump body, a hydraulic chamber is arranged in the pump body, the power assembly is provided with a plunger, and the plunger slides in the hydraulic chamber of the pump body; a first sealing group is installed in the hydraulic chamber of the pump body, the first sealing group is sealingly and slidingly connected to the plunger, and the first sealing group is used to seal the plunger and the hydraulic chamber in an initial state; a sealing member is slidingly connected to a side of the plunger away from the hydraulic chamber, a second sealing group and a third sealing group are installed on the sealing member, the second sealing group is sealingly and slidingly connected to the plunger, and the second sealing group is used to seal the plunger and the hydraulic chamber when the sealing of the first sealing group fails; a detection locking mechanism is arranged on the pump body, and is used to detect the sealing state of the first sealing group and lock the seal.

[0005] Preferably, the detection locking mechanism includes: a sealing shell, fixedly connected to the pump body, a detection cavity is arranged in the sealing shell, a sliding gap is arranged between the sealing shell and the plunger, and the third sealing group is used to seal the sealing member and the sealing shell; a first detection airbag, fixedly connected to the detection cavity of the sealing shell; a detection tank, fixedly connected to the sealing shell, the detection tank is connected with the first detection airbag, a sliding piston is slidably connected in the detection tank, a first pressure sensor is fixedly connected to one side of the sliding piston close to the connection between the detection tank and the first detection airbag, and the first pressure sensor is used to detect the state of the air pressure in the first detection airbag; a comparison component, arranged outside the sealing shell, for reducing the detection error of the first detection airbag; a locking assembly, arranged on the sealing shell, for locking the position of the sealing member.

[0006] Preferably, the comparison component includes: a second detection airbag fixedly connected to the outer side of the sealing shell, the second detection airbag is connected to the detection tank; and a second pressure sensor fixedly connected to the sliding piston.

[0007] Preferably, the sealed housing is equipped with a touch switch, and the sliding piston is used to activate the touch switch.

[0008] Preferably, the locking assembly includes: a sliding ring, rotatably connected to the sealing shell, the sliding ring is provided with circumferentially spaced folding grooves, and an inclined surface is provided in the folding grooves; a plurality of limit blocks, which are circumferentially spaced and fixed to the sealing member, the limit blocks corresponding one-to-one to the folding grooves, the folding grooves are used to lock adjacent limit blocks, and the limit blocks are used to squeeze the inclined surface; a guide assembly, the number of which corresponds one-to-one to the number of the limit blocks, and they are respectively provided on the limit blocks to control the rotation of the sliding ring.

[0009] Preferably, the guiding assembly includes: a first magnetic block, fixedly connected to a side of the adjacent limiting block close to the sealing shell, the sealing shell being fixedly connected to a first electromagnet, the first electromagnet and the first magnetic block being magnetically attracted to each other; a second magnetic block, fixedly connected to a side of the adjacent limiting block close to the sealing shell, the sliding ring being fixedly connected to a second electromagnet, the second electromagnet and the second magnetic block being magnetically attracted to each other.

[0010] Preferably, the sealing shell is slidably connected to a limiting ball, and a first spring is installed between the two, and the limiting ball is used to limit the sliding ring.

[0011] Preferably, the second detection airbag is located between the sealing member and the sealing shell, and the sealing shell is provided with a pressure relief valve, which is communicated with the second detection airbag.

[0012] Preferably, it also includes: reinforced limiting members, the number of which corresponds to the number of the limiting blocks, and are all fixed to a side of the sliding ring close to the sealing member, for limiting the limiting blocks.

[0013] Preferably, it further comprises: a buffer tank fixedly connected in the sealing member, the sealing member is provided with a channel communicating with the buffer tank, a sliding plate is slidably connected in the buffer tank, and a second spring is installed between the two.

[0014] The present invention has at least the following beneficial effects: the present invention uses two sets of sealing structures, namely the first sealing group and the second sealing group and the third sealing group, to jointly complete the sealing task. When the first sealing group works normally, the unnecessary wear of the second sealing group is reduced. When the first sealing group leaks, the second sealing group and the third sealing group replace the first sealing group for sealing, thereby protecting the internal use environment of the device and keeping the internal environment of the device in a high-pressure state at all times, thereby increasing the continuous use time of the device and reducing the probability of unplanned shutdown.

[0015] The present invention compares the detection data of the first pressure sensor with the detection data of the second pressure sensor, thereby improving the detection accuracy of whether the first sealing group has leaked, while reducing the detection error caused by unexpected situations during the operation of the device, thereby reducing the probability of the locking component being triggered by mistake.

[0016] The present invention uses a buffer tank to buffer the hydraulic impact generated when the seal and the sealing shell are locked, thereby reducing the resistance when the seal and the sealing shell are locked, thereby increasing the stability of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0018] Figure 2 It is a three-dimensional structural schematic diagram of the plunger, the first sealing group and the sealing member of the present invention;

[0019] Figure 3 It is a three-dimensional structural schematic diagram of the plunger, the sealing shell and the sliding ring of the present invention;

[0020] Figure 4 is a cross-sectional view of the seal and the third seal group of the present invention;

[0021] Figure 5 It is a schematic diagram of the three-dimensional structure of the detection cavity and the sliding gap of the present invention;

[0022] Figure 6 An exploded view of the sealing shell, the first detection airbag and the sliding ring of the present invention;

[0023] Figure 7It is a schematic diagram of the three-dimensional structure of the first detection airbag and the second detection airbag of the present invention;

[0024] Figure 8 It is a schematic diagram of the three-dimensional structure of the detection tank and the sliding ring of the present invention;

[0025] Fig. 9 It is a schematic diagram of the three-dimensional structure of the sealing member, the sliding ring and the limit block of the present invention;

[0026] Fig.10 It is a three-dimensional structural schematic diagram of the sliding ring, the limiting block and the enhanced limiting member of the present invention;

[0027] Fig.11 It is a schematic diagram of the three-dimensional structure of the sealing element and the buffer tank of the present invention;

[0028] Fig.12 It is a cross-sectional view of the seal and buffer tank of the present invention.

[0029] Marked in the figure: 1-power assembly, 2-pump body, 3-plunger, 4-first sealing group, 5-seal, 51-second sealing group, 52-third sealing group, 6-sealing shell, 601-detection chamber, 602-sliding gap, 7-first detection airbag, 8-detection tank, 81-sliding piston, 82-first pressure sensor, 83-touch switch, 9-second detection airbag, 91-second pressure sensor, 10-sliding ring, 101-first electromagnet, 102-second electromagnet, 103-folding slide groove, 104-inclined surface, 105-sliding part, 106-locking part, 11-limiting block, 111-first magnetic block, 112-second magnetic block, 12-enhanced limiting member, 15-pressure relief valve, 16-limiting ball, 17-buffer tank, 18-sliding plate. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] A plunger type fracturing pump with a protective structure, such as Figure 1-Figure 4As shown, it includes: a power assembly 1, the power assembly 1 is fixedly connected to a pump body 2, a hydraulic chamber is arranged in the pump body 2, the power assembly 1 is provided with a plunger 3, and the plunger 3 slides in the hydraulic chamber of the pump body 2; a first sealing group 4 is installed in the hydraulic chamber of the pump body 2, the first sealing group 4 is sealingly and slidably connected to the plunger 3, and the first sealing group 4 is used to seal the plunger 3 and the hydraulic chamber in the initial state; a sealing member 5 is slidably connected to the side of the plunger 3 away from the hydraulic chamber, and a second sealing group 51 and a third sealing group 52 are installed on the sealing member 5, the second sealing group 51 is sealingly and slidably connected to the plunger 3, and the second sealing group 51 is used to seal the plunger 3 and the hydraulic chamber when the sealing of the first sealing group 4 fails; a detection locking mechanism is arranged on the pump body 2, and is used to detect the sealing state of the first sealing group 4 and lock the sealing member 5.

[0032] In the above scheme, the number of hydraulic chambers in the pump body 2 and the number of plungers 3 can be changed according to actual conditions. Figure 1 The number of hydraulic chambers and the number of plungers 3 in the pump body 2 are both three. The hydraulic chamber in the pump body 2 is connected to the pipeline for conveying fracturing fluid through a pipeline. In this scheme, the frontmost hydraulic chamber in the pump body 2 and the frontmost plunger 3 are always described; the power assembly 1 and the detection mechanism are electrically connected to the external control terminal; the third sealing group 52 is located on the right side of the seal 5, and the second sealing group 51 is located between the seal 5 and the plunger 3. There is friction damping between the second sealing group 51 and the plunger 3. In the initial state, the seal 5 moves back and forth with the plunger 3 driven by the second sealing group 51, and the seal 5, the second sealing group 51 and the plunger 3 are in a relatively fixed state. Therefore, in the above state, no wear will occur between the second sealing group 51 and the plunger 3, reducing the occurrence of ineffective wear.

[0033] Preferably, if Figure 2 , Figure 3 and Figure 5-Figure 7 As shown, the detection locking mechanism includes: a sealing shell 6, which is fixedly connected to the pump body 2, a detection cavity 601 is arranged in the sealing shell 6, a sliding gap 602 is arranged between the sealing shell 6 and the plunger 3, and a third sealing group 52 is used to seal the sealing member 5 and the sealing shell 6; a first detection airbag 7, which is fixedly connected to the detection cavity 601 of the sealing shell 6; a detection tank 8, which is fixedly connected to the sealing shell 6, the detection tank 8 is connected to the first detection airbag 7, a sliding piston 81 is slidably connected in the detection tank 8, and a first pressure sensor 82 is fixedly connected to one side of the sliding piston 81 close to the connection between the detection tank 8 and the first detection airbag 7, and the first pressure sensor 82 is used to detect the state of the air pressure in the first detection airbag 7; a comparison component, which is arranged outside the sealing shell 6, and is used to reduce the detection error of the first detection airbag 7; a locking component, which is arranged on the sealing shell 6, and is used to lock the position of the sealing member 5.

[0034] In the above scheme, the sealing shell 6 is coaxial with the plunger 3 and the two do not contact each other. The minimum distance between the sealing shell 6 and the plunger 3 (i.e., the sliding gap 602) is less than 1 mm, which is used to reduce the probability of the leaked liquid being directly sprayed out from the sliding gap 602. Since the cross-sectional area of ​​the sliding gap 602 is small, the leaked liquid cannot be discharged from the detection cavity 601 in time, thereby increasing the accuracy of the first detection airbag 7 in monitoring the liquid pressure; the sealing shell 6 and the plunger 3 do not contact each other, so there is no wear between the two, and there is no liquid in the detection cavity 601 in the initial state; the first pressure sensor 82 and the locking assembly are electrically connected to the control terminal.

[0035] Preferably, if Figure 6-Figure 8 As shown, the comparison components include: a second detection airbag 9, which is fixed to the outer side of the sealing shell 6 and communicated with the detection tank 8; and a second pressure sensor 91, which is fixed to the sliding piston 81.

[0036] Preferably, if Figure 7 and Figure 8 As shown, the sealed housing 6 is installed with a touch switch 83 , and the sliding piston 81 is used to activate the touch switch 83 .

[0037] In the above scheme, the second detection airbag 9 is used as a control group for the first detection airbag 7. The second pressure sensor 91 is used to detect the change of the air pressure in the second detection airbag 9, and then the change of the air pressure in the second detection airbag 9 caused by the vibration of the device is detected. The control terminal eliminates the influence of the vibration of the device on the change of the gas pressure in the first detection airbag 7 by comparing the data transmitted by the second pressure sensor 91, thereby reducing the probability of the locking component being triggered by mistake. The second detection airbag 9 is located on the outside of the sealing shell 6, and the inner diameter of the second detection airbag 9 is larger than the inner diameter of the leftmost side of the sealing shell 6, and the gas pressure in the first detection airbag 7 is equal to the gas pressure in the second detection airbag 9 in the initial state; the second pressure sensor 91 and the touch switch 83 are both electrically connected to the control terminal, and the touch switch 83 is used for double triggering to increase the reliability of the device.

[0038] Preferably, if Figure 8-Figure 11 As shown, the locking assembly includes: a sliding ring 10, which is rotatably connected to the sealing shell 6, and the sliding ring 10 is provided with circumferentially spaced folding grooves 103, and the folding grooves 103 are provided with inclined surfaces 104; a plurality of limit blocks 11, which are circumferentially spaced and fixed to the sealing member 5, and the limit blocks 11 correspond one-to-one to the folding grooves 103, and the folding grooves 103 are used to lock adjacent limit blocks 11, and the limit blocks 11 are used to squeeze the inclined surfaces 104; a guide assembly, the number of which corresponds one-to-one to the number of the limit blocks 11, and they are respectively arranged on the limit blocks 11, and are used to control the rotation of the sliding ring 10.

[0039] In the above scheme, the number of the folding slide grooves 103 and the number of the limit blocks 11 are both three. The folding slide groove 103 has a sliding portion 105 and a locking portion 106. The inclined surface 104 is located at a position where the sliding portion 105 and the locking portion 106 are interconnected. The sliding portion 105 is used to guide the limit block 11 into the adjacent locking portion 106. The limit block 11 slides in the left and right directions along the sliding portion 105, and the locking portion 106 is used to lock the position of the adjacent limit block 11.

[0040] Preferably, if Fig. 9 and Fig.10 As shown, the guiding assembly includes: a first magnetic block 111, which is fixedly connected to a side of the adjacent limit block 11 close to the sealing shell 6, the sealing shell 6 is fixedly connected to a first electromagnet 101, and the first electromagnet 101 and the first magnetic block 111 are magnetically attracted to each other; a second magnetic block 112, which is fixedly connected to a side of the adjacent limit block 11 close to the sealing shell 6, the sliding ring 10 is fixedly connected to a second electromagnet 102, and the second electromagnet 102 and the second magnetic block 112 are magnetically attracted to each other.

[0041] In the above scheme, the first magnetic block 111 is fixedly connected to the right side of the adjacent limit block 11, and in the initial state, the first magnetic block 111 is aligned with the sliding part 105 of the adjacent folding groove 103, the first magnetic block 111 and the first electromagnet 101 are located on the same horizontal line, the second electromagnet 102 is aligned with the locking part 106 of the adjacent folding groove 103, and is located on the side of the adjacent locking part 106 away from the adjacent inclined surface 104, and the second magnetic block 112 is fixedly connected to the side of the adjacent limit block 11.

[0042] Preferably, if Fig.11 and Fig.12 As shown, the sealing shell 6 is slidably connected to the limiting ball 16 , and a first spring is installed between the two. The limiting ball 16 is used to limit the sliding ring 10 .

[0043] In the above solution, the limiting ball 16 is used to limit the sliding ring 10 at the initial position to prevent the sliding ring 10 from rotating due to unexpected reasons (such as vibration) during the operation of the device.

[0044] Preferably, if Figure 8 As shown, the second detection airbag 9 is located between the sealing member 5 and the sealing shell 6 , and the sealing shell 6 is provided with a pressure relief valve 15 , which is communicated with the second detection airbag 9 .

[0045] In the above solution, the second detection airbag 9 is used to buffer the impact force between the seal 5 and the sealing shell 6; in the initial state, the seal 5 does not contact the second detection airbag 9 while following the reciprocating movement of the plunger 3.

[0046] If the second detection airbag 9 is always in an expanded state, when the third sealing group 52 squeezes the second detection airbag 9, the gas in the second detection airbag 9 will be affected by squeezing and vibration, and flow back and forth in the second detection airbag 9, causing the third sealing group 52 to be repeatedly squeezed to the left by the second detection airbag 9 and the gas therein, which eventually leads to an unstable sealing state between the seal 5 and the sealing shell 6. Therefore, a pressure relief valve 15 is installed on the sealing shell 6. The pressure relief valve 15 is used to discharge the gas in the second detection airbag 9 when the second detection airbag 9 is squeezed, and then when the third sealing group 52 and the second detection airbag 9 jointly seal the gap between the seal 5 and the sealing shell 6, the influence of the gas in the second detection airbag 9 on the sealing effect between the seal 5 and the sealing shell 6 is reduced.

[0047] The working process is as follows: when the staff needs to perform fracturing operations, the staff first starts the power assembly 1 through the control terminal, and the power assembly 1 drives the plunger 3 to reciprocate in the left and right directions. The hydraulic chamber in the pump body 2 extracts and delivers the fracturing fluid through the reciprocating motion of the plunger 3 (the above process is the same as the prior art, so it will not be described in detail). In the initial working state, when the plunger 3 reciprocates, the damping between the plunger 3 and the second sealing group 51 drives the seal 5, the second sealing group 51 and the third sealing group 52 to move together, and the upper limit block 11 of the seal 5 is During the movement, it repeatedly enters the adjacent sliding portion 105, but during the above-mentioned movement, the limit block 11 never enters the adjacent locking portion 106, does not contact the inclined surface 104, the second sealing group 51 and the third sealing group 52 are not subjected to friction, the third sealing group 52 does not contact the second detection airbag 9, the plunger 3 mainly relies on the first sealing group 4 for sealing, the sliding ring 10 is limited by the limiting ball 16 and cannot rotate relative to the sealing shell 6, there is no fracturing fluid in the detection cavity 601, and the first detection airbag 7 and the second detection airbag 9 are only in contact with air.

[0048] The device may generate certain vibrations during operation. Since the first detection airbag 7 and the second detection airbag 9 are both fixedly connected to the sealing shell 6, the vibration of the sealing shell 6 will drive the first detection airbag 7 and the second detection airbag 9 to vibrate together. The first detection airbag 7 and the second detection airbag 9 periodically squeeze the gas inside each other when vibrating. The gas in the first detection airbag 7 and the gas in the second detection airbag 9 fluctuate due to the squeezing. Since the first detection airbag 7 and the second detection airbag 9 are subjected to the same vibration intensity, the fluctuations of the air pressure in the first detection airbag 7 and the air pressure in the second detection airbag 9 due to the vibration of the device are equal. At this time, the fluctuation frequency of the detection value of the first pressure sensor 82 and the detection value of the second pressure sensor 91 are equal.

[0049] When there is no leakage in the first sealing group 4, the control terminal monitors that the detection value of the first pressure sensor 82 and the detection value of the second pressure sensor 91 have the same change pattern, so it can be known that the change is caused by the vibration of the device (that is, not caused by the leakage of the fracturing fluid), thereby reducing the probability of the device being triggered by mistake.

[0050] When the first sealing group 4 leaks, the leaked fracturing fluid first enters the detection chamber 601. If the amount of fracturing fluid that initially enters the detection chamber 601 is small, the gas pressure in the first detection airbag 7 does not change significantly. However, due to the small flow area at the sliding gap 602 (the minimum spacing between the sealing shell 6 and the plunger 3 is less than 1 mm), the fracturing fluid in the detection chamber 601 cannot be discharged in time, and the leaked fracturing fluid in the detection chamber 601 gradually accumulates in the lower part of the detection chamber 601. At this time, the fracturing fluid gradually squeezes the lower part of the first detection airbag 7, causing the first detection airbag 7 to The gas pressure in the airbag 7 gradually increases. If the amount of fracturing fluid that initially enters the detection chamber 601 is large, the first detection airbag 7 is squeezed by the fracturing fluid, and the gas pressure therein increases rapidly. When the gas pressure in the first detection airbag 7 increases due to the leakage of the fracturing fluid, the gas pressure in the first detection airbag 7 is greater than the gas pressure in the second detection airbag 9. The gas in the first detection airbag 7 flows into the detection tank 8 and pushes the sliding piston 81 to move to the left. The sliding piston 81 squeezes the gas on its left side into the second detection airbag 9. The gas pressure in the second detection airbag 9 gradually increases. Increase, at this time, the gas pressure increase speed in the first detection airbag 7 is slightly faster than the gas pressure increase speed in the second detection airbag 9. At this time, the control terminal reads the gas pressure data in the first pressure sensor 82 and the second pressure sensor 91, and knows that the detection values ​​of the two are successively increased. The control terminal knows that a leak occurs at the first sealing group 4 and promptly starts the locking assembly, so that the sealing member 5 and the sealing shell 6 seal the plunger 3 together, thereby increasing the sealing performance of the device, so that the second sealing group 51 and the third sealing group 52 replace the first sealing group 4 for sealing, increasing the continuous use time of the device, and reducing the number of unplanned shutdowns. The sliding piston 81 is pushed by the gas in the first detection airbag 7 to move continuously to the left until the sliding piston 81 contacts the touch switch 83 and activates the touch switch 83. The touch switch 83 sends a signal to the control terminal again, reminding the control terminal that a leak occurs at the first sealing group 4, increasing the detection means of the control terminal, and reducing the probability that the first pressure sensor 82 and the second pressure sensor 91 are accidentally damaged, causing the control terminal to be unable to start the locking assembly in time.

[0051] When the control terminal controls to start the locking component, all the first electromagnets 101 and all the second electromagnets 102 are started. When the plunger 3 drives the seal 5, the second sealing group 51 and the third sealing group 52 to move to the rightmost end of the stroke, the upper limit block 11 of the seal 5 is inserted into the sliding part 105 of the adjacent folding groove 103. At this time, the first magnetic block 111 on the limit block 11 has moved to the magnetic attraction range of the first electromagnet 101, and the second magnetic block 112 has moved to the magnetic attraction range of the second electromagnet 102. At this time, the limit block 11 is affected by the magnetic force between the first magnetic block 111 and the first electromagnet 101, and the limit block 11 drives the seal 5 to move to the right actively (overcoming the friction damping between the second sealing group 51 and the plunger 3), and the seal 5 drives the second sealing group 51 and the third sealing group 52 to move rightward together, the plunger 3 slides relatively with the second sealing group 51, the limiting block 11 first contacts the adjacent inclined surface 104 during the movement, and gradually enters the adjacent locking portion 106, the second electromagnet 102 and the second magnetic block 112 are gradually aligned, the limiting block 11 squeezes the adjacent inclined surface 104 to make the sliding ring 10 rotate counterclockwise (from right to left perspective), the sliding ring 10 squeezes the limiting ball 16 into the sealing shell 6, the first spring on the limiting ball 16 is compressed and stored, and at the same time the third sealing group 52 gradually contacts the second detection airbag 9 and squeezes the gas in the second detection airbag 9, the gas in the second detection airbag 9 is compressed and stored, and the gas pressure in the second detection airbag 9 suddenly increases. When the pressure of the gas in the second detection airbag 9 is greater than that of the gas in the first detection airbag 7, the sliding piston 81 moves to the right and resets under the push of the gas in the second detection airbag 9. The second detection airbag 9 buffers the sealing member 5, the second sealing group 51 and the third sealing group 52, reducing the impact force when the sealing member 5 collides with the sealing shell 6. When the gas in the second detection airbag 9 accumulates to a value higher than the pressure relief valve 15, the gas in the second detection airbag 9 is discharged outward from the pressure relief valve 15, reducing the force of the gas expansion in the second detection airbag 9 pushing the third sealing group 52 in the opposite direction. The third sealing group 52 squeezes the second detection airbag 9 to make the left and right sides of the second detection airbag 9 fit each other. The third sealing group 52 and the second detection airbag 9 jointly complete the sealing between the sealing member 5 and the sealing shell 6. When the gas in the second detection airbag 9 is completely discharged, the limit block 11 completely slides to the right part of the adjacent folding slot 103. At this time, the sliding ring 10 continues to rotate counterclockwise relative to the sliding ring 10 (from right to left perspective) under the magnetic force of the second magnetic block 112 and the second electromagnet 102, so that the limit block 11 completely enters the locking part 106 of the folding slot 103. At this time, the limit block 11 is limited by the locking part 106 on the folding slot 103 and can no longer move left and right relative to the sealing shell 6. The sealing member 5 and the sealing shell 6 are in a relatively fixed state. The second sealing group 51 and the third sealing group 52 jointly replace the first sealing group 4 to seal the plunger 3. Then the control terminal turns off all the first electromagnets 101 and all the second electromagnets 102.After the leaked fracturing fluid fills the detection chamber 601, the fracturing fluid flows from the sliding gap 602 to the gap between the seal 5 and the sealing shell 6. At this time, since the third sealing group 52 and the second detection airbag 9 seal the seal 5 and the sealing shell 6, and the second sealing group 51 seals the seal 5 and the plunger 3, the fracturing fluid cannot continue to spray out, and the pressure in the pump body 2 gradually returns to the normal working state.

[0052] When the staff inspects and maintains the device, the staff first shuts down the power assembly 1 through the control terminal, and drains the fracturing fluid in the pump body 2 and the detection chamber 601. The first detection airbag 7 returns to its original state under the action of the expansion of the gas therein, and then the staff manually resets the sliding ring 10 to release the lock of the folding groove 103 on the limit block 11. Then the staff uses existing tools to push the seal 5 and other components to reset, and refills the second detection airbag 9 with gas through existing devices. When the gas pressure in the second detection airbag 9 increases, it pushes the sliding piston 81 to reset to the initial state synchronously. Then the staff uses existing devices to adjust the air pressure in the second detection airbag 9 to a state equal to the air pressure in the first detection airbag 7. Finally, the staff focuses on the maintenance and replacement of the first sealing group 4, the second sealing group 51 and the third sealing group 52.

[0053] Preferably, if Fig. 9 and Fig.10 As shown, it also includes: enhanced limiting members 12 , the number of which corresponds to the number of limiting blocks 11 , and both are fixed to a side of the sliding ring 10 close to the sealing member 5 , for limiting the limiting blocks 11 .

[0054] In the above scheme, there are three reinforced limit members 12 on a sliding ring 10. When following the rotation of the sliding ring 10, the reinforced limit member 12 actively clamps the left side of the adjacent limit block 11, thereby fixing the adjacent limit block 11 to increase the effect of the sliding ring 10 fixing the limit block 11.

[0055] Preferably, if Fig.11 and Fig.12 As shown, it also includes: a buffer tank 17, which is fixed in the sealing member 5. The sealing member 5 is provided with a channel communicating with the buffer tank 17. A sliding plate 18 is slidably connected in the buffer tank 17, and a second spring is installed between the two.

[0056] In the above scheme, when the leakage of the first sealing group 4 is large, the fracturing fluid quickly fills the detection cavity 601 and sprays out through the sliding gap 602. If the sealing member 5 and the sealing shell 6 have not yet completed the above locking process, the fracturing fluid will quickly fill the gap between the sealing member 5 and the sealing shell 6. Then the fracturing fluid will push the sealing member 5 to the left through the liquid pressure, causing the sealing member 5 and the sealing shell 6 to disperse due to the impact. The number of buffer tanks 17 can be multiple, and the shape of the buffer tank 17 can be an annular container. The cross-sectional area of ​​the channel on the sealing member 5 is larger than that of the sliding member 6. The cross-sectional area where the liquid can flow at the gap 602. The sliding plate 18 is initially located on the right side of the buffer tank 17. When the first sealing group 4 fails suddenly, the fracturing fluid in the detection chamber 601 is ejected outward through the sliding gap 602 after pressure accumulation. The seal 5 and the sealing shell 6 are locked according to the same steps as above. At this time, the fracturing fluid cannot be ejected outward, but flows into the buffer tank 17 through the channel on the seal 5. The fracturing fluid squeezes the sliding plate 18 to move to the left, and the second spring on the sliding plate 18 is compressed and stored, thereby buffering the fracturing fluid and reducing the probability of water hammer.

[0057] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of those skilled in the art without departing from the spirit of the present invention.

Claims

1. A plunger-type fracturing pump with a protective structure, characterized in that: Included are: A power assembly (1), the power assembly (1) being fixedly connected to a pump body (2), the pump body (2) being provided with a hydraulic cavity, the power assembly (1) being provided with a plunger (3), the plunger (3) sliding in the hydraulic cavity of the pump body (2); a first sealing group (4) installed in the hydraulic chamber of the pump body (2), the first sealing group (4) being sealingly slidably connected to the plunger (3), the first sealing group (4) being used to seal the plunger (3) and the hydraulic chamber in an initial state; A sealing member (5) is slidably connected to a side of the plunger (3) away from the hydraulic chamber, a second sealing group (51) and a third sealing group (52) are mounted on the sealing member (5), the second sealing group (51) is sealingly slidably connected to the plunger (3), and the second sealing group (51) is used to seal the plunger (3) and the hydraulic chamber when the sealing of the first sealing group (4) fails; A detection locking mechanism, arranged on the pump body (2), used for detecting the sealing state of the first sealing group (4) and locking the sealing element (5); The detection locking mechanism comprises: A sealing shell (6) is fixedly connected to the pump body (2), a detection cavity (601) is provided in the sealing shell (6), a sliding gap (602) is provided between the sealing shell (6) and the plunger (3), and the third sealing group (52) is used to seal the sealing element (5) and the sealing shell (6); A first detection airbag (7) fixedly connected to the detection cavity (601) of the sealing shell (6); A detection tank (8) is fixedly connected in the sealing shell (6); the detection tank (8) is connected to the first detection airbag (7); a sliding piston (81) is slidably connected in the detection tank (8); a first pressure sensor (82) is fixedly connected to one side of the sliding piston (81) close to the connection between the detection tank (8) and the first detection airbag (7); the first pressure sensor (82) is used to detect the state of the air pressure in the first detection airbag (7); A comparison component, arranged outside the sealing shell (6), and used to reduce a detection error of the first detection airbag (7); A locking assembly is arranged on the sealing shell (6) and is used to lock the position of the sealing element (5).

2. A plunger-type fracturing pump with a protective structure according to claim 1, characterized in that: The comparison components include: A second detection airbag (9) is fixedly connected to the outer side of the sealing shell (6), and the second detection airbag (9) is connected to the detection tank (8); The second pressure sensor (91) is fixedly connected to the sliding piston (81).

3. The plunger-type fracturing pump with a protective structure according to claim 2, characterized in that: The sealing shell (6) is installed with a touch switch (83), and the sliding piston (81) is used to activate the touch switch (83).

4. The plunger-type fracturing pump with a protective structure according to claim 3, characterized in that: The locking assembly comprises: A sliding ring (10) is rotatably connected to the sealing shell (6), the sliding ring (10) being provided with circumferentially spaced folding slide grooves (103), and an inclined surface (104) being provided in the folding slide groove (103); A plurality of limit blocks (11) are circumferentially spaced and fixedly connected to the sealing member (5); the limit blocks (11) correspond to the folding slide grooves (103) one by one; the folding slide grooves (103) are used to lock adjacent limit blocks (11); and the limit blocks (11) are used to press the inclined surface (104); The number of guide components corresponds to the number of the limit blocks (11) and are respectively arranged on the limit blocks (11) and are used to control the rotation of the sliding ring (10).

5. The plunger-type fracturing pump with a protective structure according to claim 4, characterized in that: The guide component comprises: A first magnetic attraction block (111) is fixedly connected to a side of the adjacent limiting block (11) close to the sealing shell (6); the sealing shell (6) is fixedly connected to a first electromagnet (101); the first electromagnet (101) and the first magnetic attraction block (111) are magnetically attracted to each other; The second magnetic attraction block (112) is fixedly connected to a side of the adjacent limit block (11) close to the sealing shell (6), and the sliding ring (10) is fixedly connected to a second electromagnet (102), and the second electromagnet (102) and the second magnetic attraction block (112) are magnetically attracted to each other.

6. The plunger-type fracturing pump with a protective structure according to claim 5, characterized in that: The sealing shell (6) is slidably connected to a limiting ball (16), and a first spring is installed between the two. The limiting ball (16) is used to limit the sliding ring (10).

7. The plunger-type fracturing pump with a protective structure according to claim 6, characterized in that: The second detection airbag (9) is located between the sealing element (5) and the sealing shell (6); the sealing shell (6) is provided with a pressure relief valve (15); and the pressure relief valve (15) is in communication with the second detection airbag (9).

8. The plunger-type fracturing pump with a protective structure according to claim 7, characterized in that: Also included are: The number of the reinforced limiting members (12) corresponds to the number of the limiting blocks (11), and are all fixedly connected to a side of the sliding ring (10) close to the sealing member (5) and are used to limit the limiting blocks (11).

9. The plunger-type fracturing pump with a protective structure according to claim 8, characterized in that: Also included are: The buffer tank (17) is fixedly connected in the sealing member (5); the sealing member (5) is provided with a passage communicating with the buffer tank (17); a sliding plate (18) is slidably connected in the buffer tank (17), and a second spring is installed between the two.

Images