Oil-gas mixed transportation double-suction double-screw pump

Abstract

The utility model discloses an oil-gas mixed transportation double-suction double-screw pump which comprises a pump body, a left-right through inner shell is arranged in the pump body, a driving shaft and a driven shaft which are parallel to each other are arranged in the inner shell in a penetrating mode, the rear ends of the driving shaft and the driven shaft are meshed after penetrating through the pump body in a sealing and rotating mode, and the front ends of the driving shaft and the driven shaft are arranged on the pump body in a sealing and rotating mode. Two blocking rings are arranged between the outer wall of the inner shell and the inner wall of the pump body in a bilateral symmetry mode, a plurality of discharging ports are formed in the position, located between the two blocking rings, of the inner shell, the positions, located in the inner shell, of the driving shaft and the driven shaft are each sleeved with a left-right two-way spiral sleeve, the two left-right two-way spiral sleeves are meshed, and an inlet shell is arranged outside the pump body. Inlet holes communicated with the inlet shell are formed in the positions, located on the outer sides of the two blocking rings, of the outer wall of the pump body, and outlet holes are formed in the positions, located on the inner sides of the two blocking rings, of the outer wall of the pump body. According to the oil-gas mixed transportation double-suction double-screw pump, when the oil viscosity is increased, the volume efficiency is improved by reducing leakage, and therefore the efficiency of the screw pump is improved.

Description

Technical Field

[0001] The utility model relates to a screw pump, and particularly to a double-suction and double-screw pump for oil and gas mixed transportation. Background Art

[0002] For the mixed transportation pumps used in oil fields for long-distance transportation of oil, gas and water, especially when the gas content and water ratio are relatively high, and in some places where the oil-gas ratio reaches 1:20, it is necessary to reduce the manifold pressure, reduce the outlet pressure of the pumping unit on the wellhead, reduce energy consumption and increase production, and reduce the probability of pipe explosion. What kind of pump to choose is a matter that puzzles many users.

[0003] According to the production experience over the years and the usage of products at the user site, professionals in this field believe that to meet the prerequisite for achieving the above process requirements is that the pump should have both the function of pumping gas like a compressor, the ability to transport liquid like a centrifugal pump, and the good transmission effect of a gear pump. Therefore, the selection of the pump is also a basic requirement to ensure the long-term, safe, stable and full-load operation of the device.

[0004] Therefore, there is an urgent need for a screw pump that can meet the above requirements to improve the efficiency of the screw pump, especially when the viscosity of the oil increases, the efficiency of the screw pump can still be improved. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a double-suction and double-screw pump for oil and gas mixed transportation. When the viscosity of the oil increases, the double-suction and double-screw pump for oil and gas mixed transportation will not only not reduce the efficiency of the screw pump, but also improve the volumetric efficiency by reducing leakage, thereby improving the efficiency of the screw pump.

[0006] To achieve the above purpose, the utility model provides a double-suction and double-screw pump for oil and gas mixed transportation, including a pump body. An inner shell that penetrates through from left to right is arranged in the pump body. A driving shaft and a driven shaft that are parallel to each other are arranged through the inner shell. The rear ends of the driving shaft and the driven shaft are sealed and rotatably penetrate through the pump body and then mesh with each other, and the front ends are sealed and rotatably arranged on the pump body. Two barrier rings are symmetrically arranged on the left and right between the outer wall of the inner shell and the inner wall of the pump body. A plurality of discharge ports are arranged on the inner shell between the two barrier rings. Left and right bidirectional spiral sleeves are sleeved on both the driving shaft and the driven shaft located in the inner shell, and the two left and right bidirectional spiral sleeves mesh with each other. An inlet housing is arranged outside the pump body. Inlet holes communicating with the inlet housing are arranged on the outer wall of the pump body on the outer sides of the two barrier rings. Outlet holes are arranged on the outer wall of the pump body on the inner sides of the two barrier rings.

[0007] Preferably, rotating supports are arranged at the open positions at both ends of the pump body. The rotating supports sequentially include a connecting plate and a mechanical seal seat from the inside to the outside. The connecting plate is detachably connected to the end of the pump body, and the mechanical seal seat is detachably connected to the connecting plate. Mechanical seal washers coaxial with the driving shaft and the driven shaft are installed on the mechanical seal seat.

[0008] Preferably, a rear bearing bracket is installed at the rear end of the pump body. A rear cover is installed on the outer side of the rear end of the rear bearing bracket, and a rear bearing seat is installed on the inner side of the rear end of the rear bearing bracket. The rear ends of the driving shaft and the driven shaft rotatably penetrate through corresponding second bearings on the rear bearing seat. A first gear is installed at the end of the driving shaft, and a second gear meshing with the first gear is installed at the rear end of the driven shaft.

[0009] Preferably, first positioning keys matching the left - right bidirectional spiral sleeve are arranged on the outer sides of the driving shaft and the driven shaft. Collars for stopping the left - right bidirectional spiral sleeve are sleeved at both ends of the left - right bidirectional spiral sleeve on the driving shaft and the driven shaft. The side surface of the collar is fixed to the side surface of the driving shaft or the driven shaft by a set screw.

[0010] Preferably, a front bearing bracket is installed in front of the pump body. A front bearing seat is installed at the front end of the front bearing bracket. The front ends of the driving shaft and the driven shaft rotatably penetrate through corresponding first bearings on the front bearing seat.

[0011] Preferably, a through cover coaxial with the driving shaft is provided at the front end of the front bearing seat, and a blind cover coaxial with the driven shaft is provided at the front end of the front bearing seat.

[0012] Preferably, a first skeleton oil seal is arranged on the through cover, and a second skeleton oil seal is arranged at the rear end of the front bearing seat. The driving shaft penetrates through the first skeleton oil seal and the second skeleton oil seal.

[0013] Preferably, an outlet pipe is connected to the outlet hole. A communicating pipe is arranged between the inlet housing and the outlet pipe. A safety valve is installed at one end of the communicating pipe close to the inlet housing, and a check valve is installed at one end of the communicating pipe close to the outlet pipe.

[0014] According to the above technical solution, the present utility model provides an oil-gas mixed transportation double-suction double-screw pump, which includes a pump body. An inner shell that penetrates through from left to right is arranged inside the pump body. A driving shaft and a driven shaft that are parallel to each other are arranged through the inner shell. The rear ends of the driving shaft and the driven shaft are sealed and rotatably pass through the pump body and then mesh with each other, and the front ends are rotatably arranged on the pump body in a sealed manner. Two barrier rings are symmetrically arranged on the left and right between the outer wall of the inner shell and the inner wall of the pump body. A plurality of discharge ports are arranged on the inner shell between the two barrier rings. Left-right bidirectional spiral sleeves are sleeved on both the driving shaft and the driven shaft located in the inner shell. The two left-right bidirectional spiral sleeves mesh with each other. An inlet housing is arranged outside the pump body. Inlet holes communicating with the inlet housing are arranged on the outer wall of the pump body on the outer sides of the two barrier rings. Outlet holes are arranged on the outer wall of the pump body on the inner sides of the two barrier rings.

[0015] The working principle and beneficial effects of this oil-gas mixed transportation double-suction double-screw pump are as follows: This oil-gas mixed transportation double-suction double-screw pump adopts a driving shaft and a driven shaft arranged in parallel. The driving shaft and the driven shaft are synchronously rotated by meshing one end of them. Left-right bidirectional spiral sleeves are respectively sleeved on the driving shaft and the driven shaft at the position of the inner shell. The two left-right bidirectional spiral sleeves mesh with each other. There is not much force transmission and interaction between the driving shaft and the driven shaft during normal meshing rotation, so that the double-screw pump works in a very good balanced state. The oil-gas mixture enters the inner cavity of the pump through the inlet housing and then through the inlet holes at both ends respectively. The left-right bidirectional spiral sleeves push the oil-gas mixtures at both ends towards the position of the middle discharge port, and finally the oil-gas mixture is discharged from the discharge port. Through the push of the two meshing left-right bidirectional spiral sleeves, on the one hand, the suction force on the oil-gas mixture is increased. In addition, due to the meshing between the left-right bidirectional spiral sleeves, the sealing performance of the oil-gas mixture during the pushing process can also be increased, and the leakage of the oil-gas mixture during the pushing process can be reduced. Especially when the viscosity of the oil increases, using this screw pump will not only not reduce the efficiency of the screw pump, but also improve the volumetric efficiency by reducing leakage, thereby improving the efficiency of the screw pump.

[0016] Other features and advantages of the present utility model will be described in detail in the subsequent specific implementation part. Brief Description of the Drawings

[0017] The drawings are used to provide a further understanding of the present utility model and constitute a part of the specification. Together with the following specific implementation manners, they are used to explain the present utility model, but do not constitute a limitation to the present utility model. In the drawings:

[0018] Figure 1 It is a schematic diagram of the internal structure of a preferred implementation manner of the oil-gas mixed transportation double-suction double-screw pump;

[0019] Figure 2It is a front view structural schematic diagram of a preferred embodiment of an oil-gas mixed transportation double-suction double-screw pump;

[0020] Figure 3 It is a left view structural schematic diagram of a preferred embodiment of an oil-gas mixed transportation double-suction double-screw pump.

[0021] Explanation of reference numerals

[0022] 1 - Pump body; 2 - Connecting plate; 3 - Rear bearing seat; 4 - Rear cover; 5 - First gear; 6 - Second gear; 7 - Sleeve; 8 - Retaining ring; 9 - Retaining collar; 10 - Mechanical seal seat; 11 - Positioning ring; 12 - Driven shaft; 13 - Mechanical seal washer; 14 - Left and right hand screw sleeves; 15 - First positioning key; 16 - Driving shaft; 17 - Union nut; 18 - Front bearing seat; 19 - Blind cover; 20 - Through cover; 21 - Safety valve; 22 - Check valve; 23 - First bolt; 24 - First washer; 25 - First skeleton oil seal; 26 - Round nut; 27 - Lock washer; 28 - Second bolt; 29 - Second washer; 30 - First bearing; 31 - First nut; 32 - First stud; 33 - Third washer; 34 - Set screw; 35 - First screw; 36 - Fourth washer; 37 - Second bearing; 38 - Hole retaining ring; 39 - Second positioning key; 40 - Connecting pipe; 41 - Second screw; 42 - Fifth washer; 43 - Second nut; 44 - Second stud; 45 - Sixth washer; 46 - Third screw; 47 - Seventh washer; 48 - Outlet pipe; 49 - Second skeleton oil seal; 50 - Barrier ring; 51 - Inner shell; 52 - First plug; 53 - Third positioning key; 54 - Inlet housing; 55 - Discharge port. Specific embodiments

[0023] The following details the specific embodiments of the present invention in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention.

[0024] In the present invention, unless otherwise stated, the orientation terms such as "up and down, left and right, front and back, inside and outside" included in the terms only represent the orientation of the terms in the normal use state, or the common names understood by those skilled in the art, and should not be regarded as a limitation to the terms.

[0025] See Figures 1 - 3The oil-gas mixed transportation double-suction double-screw pump shown in the figure includes a pump body 1. An inner shell 51 that penetrates through from left to right is arranged inside the pump body 1. A driving shaft 16 and a driven shaft 12 that are parallel to each other penetrate through the inner shell 51. The rear ends of the driving shaft 16 and the driven shaft 12 are hermetically rotated through the pump body 1 and then meshed with each other, and the front ends are hermetically rotatably arranged on the pump body 1. Two barrier rings 50 are symmetrically arranged on the left and right between the outer wall of the inner shell 51 and the inner wall of the pump body 1. A plurality of discharge ports 55 are arranged on the inner shell 51 between the two barrier rings 50. Left-right bidirectional spiral sleeves are sleeved on both the driving shaft 16 and the driven shaft 12 inside the inner shell 51. The two left-right bidirectional spiral sleeves are meshed with each other. An inlet housing 54 is arranged outside the pump body 1. Inlet holes communicating with the inlet housing 54 are arranged on the outer wall of the pump body 1 on the outer sides of the two barrier rings 50. Outlet holes are arranged on the outer wall of the pump body 1 on the inner sides of the two barrier rings 50.

[0026] Through the implementation of the above technical solution, the oil-gas mixed transportation double-suction double-screw pump adopts the driving shaft 16 and the driven shaft 12 arranged in parallel. The synchronous rotation is achieved by meshing one end of the driving shaft 16 and the driven shaft 12. Left-right bidirectional spiral sleeves are respectively sleeved on the driving shaft 16 and the driven shaft 12 at the position of the inner shell 51. The two left-right bidirectional spiral sleeves are meshed with each other. There is not much force transmission and interaction between the driving shaft 16 and the driven shaft 12 during normal meshing rotation, enabling the double-screw pump to work in a very good balanced state. The oil-gas mixture enters the inner cavity of the pump body 1 through the inlet housing 54 and then through the inlet holes at both ends respectively. The left-right bidirectional spiral sleeves push the oil-gas mixtures at both ends towards the position of the middle discharge port 55, and finally the oil-gas mixture is discharged from the discharge port 55. Through the push of the two meshed left-right bidirectional spiral sleeves, on the one hand, the suction force on the oil-gas mixture is increased. In addition, due to the meshing between the left-right bidirectional spiral sleeves, the sealing property of the oil-gas mixture during the pushing process can also be increased, reducing the leakage of the oil-gas mixture during the pushing process. Especially when the viscosity of the oil increases, using this screw pump will not only not reduce the efficiency of the screw pump, but also improve the volumetric efficiency by reducing leakage, thereby improving the efficiency of the screw pump.

[0027] In this embodiment, rotary supports are provided at the open positions at both ends of the pump body 1. The rotary supports sequentially include a connecting plate 2 and a mechanical seal seat 10 from inside to outside. The connecting plate 2 is detachably connected to the end of the pump body 1, and the mechanical seal seat 10 is detachably connected to the connecting plate 2. A mechanical seal washer 13 coaxial with the driving shaft 16 and the driven shaft 12 is installed on the mechanical seal seat 10. The rotary support and the pump body 1 enclose a sealed pump chamber, and rotary seals are formed between the two ends and the driving shaft 16 or the driven shaft 12 through the mechanical seal washers 13. The installation method is as follows: First, install the mechanical seal seat 10 outside the connecting plate 2, and pass a plurality of first screws 35 arranged circumferentially through the fourth gasket and the connecting plate 2 from inside to outside and then screw them into the threaded holes inside the mechanical seal seat 10. Then insert the connecting plate 2 onto a first stud 32 provided at the end of the pump body 1. A third washer 33 is sleeved on the outer end of the first stud 32, and the outer end of the third washer 33 is locked by a first nut 31. Of course, in order to facilitate the alignment of the position of the mechanical seal seat 10 during installation, a positioning ring 11 is provided inside the mechanical seal seat 10 and is inserted and positioned in cooperation with the positioning holes provided on the connecting plate 2. Of course, in order to increase the installation stability of the mechanical seal seat 10, a plurality of third screws 46 screwed onto the connecting plate 2 can also be provided outside the mechanical seal seat 10. The third screws 46 are circumferentially offset from the first screws 35, and a seventh washer 47 is sleeved on the third screws 46.

[0028] In this embodiment, a rear bearing bracket is installed at the rear end of the pump body 1. A rear cover 4 is installed on the outer side of the rear end of the rear bearing bracket, and a rear bearing seat 3 is installed on the inner side of the rear end of the rear bearing bracket. The rear ends of the driving shaft 16 and the driven shaft 12 rotatably penetrate through corresponding second bearings 37 on the rear bearing seat 3. A first gear 5 is installed at the end of the driving shaft 16, and a second gear 6 meshing with the first gear 5 is installed at the rear end of the driven shaft 12. Through the above technical solution, the driving shaft 16 rotates under the drive of an external motor, and drives the driven shaft 12 to rotate under the transmission of the first gear 5 and the second gear 6. Also, under the rotational support of the rear bearing seat 3, the rotation between the driving shaft 16 and the driven shaft 12 is more stable. The installation method is as follows: Insert a through hole preset at the inner end of the rear bearing bracket onto the first stud 32, then sleeve a third washer 33, and lock it with a first nut 31. Then insert a plurality of second studs 44 at one end of the rear bearing seat 3 facing the rear bearing bracket into the through holes preset at the rear end of the rear bearing bracket, then sleeve a sixth washer 45 and a second nut 43 to fix the rear bearing seat 3. Then install the second gear 6 of the first gear 5. A retaining ring 9 for stopping the first gear 5 or the second gear 6 is provided at the rear ends of the driving shaft 16 and the driven shaft 12, and a second positioning key 39 keyed to the first gear 5 or the second gear 6 is provided on the side surfaces at the rear ends of the driving shaft 16 and the driven shaft 12.

[0029] In addition, snap rings 8 that can be pressed against the first gear 5 or the second gear 6 are screwed onto the rear ends of the driving shaft 16 and the driven shaft 12. Sleeve bushes 7 are also provided between the first gear 5 and the driving shaft 16 and between the second gear 6 and the driven shaft 12. The sleeve bushes 7 are mounted on the corresponding first gear 5 or second gear 6 by second screws 41, and fifth washers 42 are sleeved on the second screws 41. A snap ring for hole 38 is embedded at the outer end of the bearing groove for mounting the second bearing 37 to prevent the second bearing 37 from slipping off. The side surface of the rear cover 4 is tightly mounted on the side surface of the rear bearing seat 3 through a plurality of first screw plugs 52.

[0030] In this embodiment, first positioning keys 15 that match the left and right bidirectional spiral sleeves are provided on the outer sides of the driving shaft 16 and the driven shaft 12. Collars 17 for stopping the left and right bidirectional spiral sleeves are sleeved at both ends of the left and right bidirectional spiral sleeves on the driving shaft 16 and the driven shaft 12. The side surface of the collar 17 is fixed to the side surface of the driving shaft 16 or the driven shaft 12 by set screws 34. Through the arrangement of the first positioning keys 15, it is convenient to position the left and right bidirectional spiral sleeves. Through the arrangement of the collars 17 at both ends, the positions of both ends of the left and right bidirectional spiral sleeves are defined to prevent them from moving axially. The collar 17 is of a sleeve structure, and a screw hole is provided on its side surface. The set screw 34 can be screwed into the screw hole and positioned in a preset positioning groove on the side surface of the driving shaft 16 or the driven shaft 12.

[0031] In this embodiment, a front bearing bracket is installed in front of the pump body 1. A front bearing seat 18 is installed at the front end of the front bearing bracket. The front ends of the driving shaft 16 and the driven shaft 12 rotatably penetrate through corresponding first bearings 30 on the front bearing seat 18. Through such an arrangement, stable rotation of the front ends of the driving shaft 16 and the driven shaft 12 is provided. A round nut 26 for pressing the corresponding first bearing 30 is screwed onto the front end of the driving shaft 16. A lock washer 27 is provided between the round nut 26 and the first bearing 30. A first bolt 23 is provided at the front end of the driven shaft 12. A snap ring 8 that can press the inner ring of the first bearing 30 is sleeved on the first bolt 23. A first washer 24 is provided between the snap ring 8 and the first bolt 23. The installation method of installing the front bearing seat 18 at the front end of the front bearing bracket is the same as the installation method of installing the rear bearing seat 3 at the rear end of the rear bearing bracket, and will not be elaborated here.

[0032] In this embodiment, a through cover 20 coaxial with the driving shaft 16 is covered at the front end of the front bearing seat 18, and a blind cover 19 coaxial with the driven shaft 12 is covered at the front end of the front bearing seat 18.

[0033] The through cover 20 and the blank cover 19 are both installed at the front end of the front bearing seat 18 through the second bolts 28, and a second washer 29 is sleeved on the second bolts 28. In addition, the front end of the driving shaft 16 extends out of the through cover 20, and a third positioning key 53 is arranged on the side surface of the end of the extended part. The end is shaft-connected with the driving motor to realize linkage.

[0034] In this embodiment, a first skeleton oil seal 25 is arranged on the through cover 20, a second skeleton oil seal 49 is arranged at the rear end of the front bearing seat 18, and the driving shaft 16 penetrates through the first skeleton oil seal 25 and the second skeleton oil seal 49. Through the arrangement of the first skeleton oil seal 25 and the second skeleton oil seal 49, the sealing performance is improved.

[0035] In this embodiment, an outlet pipe 48 is connected to the outlet hole, a communicating pipe 40 is arranged between the inlet housing 54 and the outlet pipe 48, a safety valve 21 is installed at one end of the communicating pipe 40 close to the inlet housing 54, and a check valve 22 is installed at one end of the communicating pipe 40 close to the outlet pipe 48. Through such an arrangement, the safety valve 21 can be opened when the pressure in the inlet housing 54 is too high, improving safety.

[0036] This twin-screw pump has independent support and non-contact for the main screw and the driven screw, and can transport materials with high viscosity and certain particles. The use efficiency is more than 10% higher than that of centrifugal pumps and gear pumps. When the output head remains unchanged, the flow rate can be increased only by changing the helix angle of the spiral sleeve, which is more suitable for the need of device capacity expansion.

[0037] The screw pump belongs to the rotary positive-displacement pump. It not only has the inherent characteristics of the positive-displacement pump, but also takes into account the main advantages of the dynamic pump, namely large flow rate, small volume, no pulsation, etc.

[0038] The advantages of the present invention will be specifically described from the following aspects:

[0039] 1. Flow rate. The flow rates of screw pumps, gear pumps, etc. do not change much with the discharge pressure. Their flow rates mainly depend on the pump specifications and the driving speed, while the flow rate of the gear pump changes with the change of the discharge pressure, and the flow rate and the head correspond one by one. It is necessary to manually control the outlet head well. This twin-screw pump can effectively control the flow rate by automatically adjusting the frequency conversion speed and automatically coordinating the relationship between the speed and the pressure, while the centrifugal pump cannot achieve the purpose of controlling the flow rate and the pressure by adjusting the speed.

[0040] 2. Pressure. For a well-sealed screw pump, the output pressure increases with the increase of load until the motor trips, the oil pump body or the oil pipe bursts. Due to the left and right-handed screw sleeves that mesh with each other in this twin-screw pump, there are many enclosed chambers with spaces between them. The pressure increases gradually from one sealed chamber to the next, so the working pressure from the suction chamber to the outlet is gradually built up. For other pumps, as the lift increases, the flow rate decreases sharply, and there is also a certain limit value for the lift.

[0041] 3. Efficiency. When the viscosity of the oil increases, the efficiency of the screw pump will not decrease but increase, because the leakage decreases and the volumetric efficiency increases at this time. For other pumps, when the liquid viscosity increases, the efficiency drops, sometimes reaching between 40% and 60%.

[0042] 4. Pulsation. The actual pressure of the screw pump has slight pulsation, but it is much smaller than that of gear pumps, vane pumps and piston pumps. Generally, the pressure pulsation of the screw pump is 1.5% - 3%, while that of gear pumps and piston pumps is 4% - 8% or even larger.

[0043] 5. Low noise. There is a small trapped volume in gear pumps, vane pumps and piston pumps, which causes the phenomenon of trapped oil, increases the noise and makes the operation unstable. While the twin-screw pump works by the movement of the sealed volume and there is no trapped volume, so there is no noise and unstable operation caused by trapped oil.

[0044] 6. Long service life. There is theoretically no contact pressure between the driving screw and the driven screw of the screw pump, and the wear of the contact surfaces of the relative moving parts in the screw pump is small, so the service life is very long.

[0045] 7. Suction capacity. The axial flow velocity of the liquid in the screw pump is low and the suction performance is good. When pumping high-viscosity liquids, the viscosity of the suction medium is generally 1 - 3×10 cst, and the applicable viscosity range of the medium is very wide.

[0046] For other pumps, the efficiency decreases greatly when transporting high-viscosity liquids. Although the linear velocity of the gear pump is relatively high, its suction capacity is still worse than that of the twin-screw pump. At the same time, due to the strong self-priming ability of the pump, it has the same conveying ability for media with extremely low viscosity containing gas and water.

[0047] 8. With energy expansion characteristics. The screw pump can control the flow rate by changing the motor speed through frequency conversion according to the flow demand of the device, so as to achieve the purpose of sharing one machine among multiple stations (wells).

[0048] 9. Large flow rate. The flow rate of gear pumps is generally from a few cubic meters per hour to more than a dozen cubic meters per hour, while that of twin-screw pumps is generally from a few cubic meters per hour to thousands of cubic meters per hour.

[0049] The preferred embodiments of the present utility model have been described in detail above in conjunction with the accompanying drawings. However, the present utility model is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present utility model, various simple modifications can be made to the technical solutions of the present utility model, and these simple modifications all fall within the protection scope of the present utility model.

[0050] In addition, it should be noted that, in the above specific embodiments, the various specific technical features described can be combined in any appropriate manner without conflict. To avoid unnecessary repetition, the present utility model will not separately describe various possible combination methods.

[0051] Furthermore, any combination can be made between the various different embodiments of the present utility model as long as it does not violate the idea of the present utility model, and it should also be regarded as the content disclosed by the present utility model.

Claims

1. A double-suction double-screw pump for oil-gas mixed transportation, characterized in that, It includes a pump body (1), inside which there is an inner shell (51) that penetrates from left to right. A driving shaft (16) and a driven shaft (12) that are parallel to each other penetrate through the inner shell (51). The rear ends of the driving shaft (16) and the driven shaft (12) are rotationally sealed through the pump body (1) and then engaged with each other, and the front ends are rotationally sealed and arranged on the pump body (1). On both sides of the outer wall of the inner shell (51) and the inner wall of the pump body (1), there are two barrier rings (50) symmetrically arranged. On the inner shell (51) between the two barrier rings (50), there are multiple discharge ports (55). On the driving shaft (16) and on the driven shaft (12) located in the inner shell (51), there are left-right bidirectional spiral sleeves sleeved. The two left-right bidirectional spiral sleeves are engaged with each other. Outside the pump body (1), there is an inlet housing (54). On the outer wall of the pump body (1), outside the two barrier rings (50), there are inlet holes communicating with the inlet housing (54). On the outer wall of the pump body (1), inside the two barrier rings (50), there are outlet holes.

2. The oil-gas mixed transportation double-suction double-screw pump according to claim 1, characterized in that, At the open positions at both ends of the pump body (1), there are rotating support members. The rotating support members successively include a connecting plate (2) and a mechanical seal seat (10) from the inside to the outside. The connecting plate (2) is detachably connected to the end of the pump body (1), and the mechanical seal seat (10) is detachably connected to the connecting plate (2). On the mechanical seal seat (10), there are installed mechanical seal washers (13) coaxial with the driving shaft (16) and the driven shaft (12) respectively.

3. The oil-gas mixed transportation double-suction double-screw pump according to claim 2, characterized in that, At the rear end of the pump body (1), there is a rear bearing bracket installed. On the outer side of the rear end of the rear bearing bracket, there is a rear cover (4) installed. On the inner side of the rear end of the rear bearing bracket, there is a rear bearing seat (3) installed. The rear ends of the driving shaft (16) and the driven shaft (12) rotate through the corresponding second bearings (37) on the rear bearing seat (3). At the end of the driving shaft (16), there is a first gear (5) installed. At the rear end of the driven shaft (12), there is a second gear (6) installed that meshes with the first gear (5).

4. The oil-gas mixed transportation double-suction double-screw pump according to claim 1, wherein, On the outer sides of the driving shaft (16) and the driven shaft (12), there are first positioning keys (15) matching the left-right bidirectional spiral sleeves. At both ends of the left-right bidirectional spiral sleeves on the driving shaft (16) and the driven shaft (12), there are collars (17) sleeved for stopping the left-right bidirectional spiral sleeves. The side of the collar (17) is fixed to the side of the driving shaft (16) or the driven shaft (12) through set screws (34).

5. The oil-gas mixed transportation double-suction double-screw pump according to claim 2, wherein, At the front of the pump body (1), there is a front bearing bracket installed. At the front end of the front bearing bracket, there is a front bearing seat (18) installed. The front ends of the driving shaft (16) and the driven shaft (12) rotate through the corresponding first bearings (30) on the front bearing seat (18).

6. The oil-gas mixed transportation double-suction double-screw pump according to claim 5, wherein, At the front end of the front bearing seat (18), there is a through cover (20) coaxially covering the driving shaft (16), and at the front end of the front bearing seat (18), there is a blind cover (19) coaxially covering the driven shaft (12).

7. The oil-gas mixed transportation double-suction double-screw pump according to claim 6, characterized in that, A first skeleton oil seal (25) is provided on the through cover (20), a second skeleton oil seal (49) is provided at the rear end of the front bearing seat (18), and the driving shaft (16) penetrates through the first skeleton oil seal (25) and the second skeleton oil seal (49).

8. The oil-gas mixed transportation double-suction double-screw pump according to claim 1, characterized in that An outlet pipe (48) is connected to the outlet hole, a communicating pipe (40) is provided between the inlet housing (54) and the outlet pipe (48), a safety valve (21) is installed at one end of the communicating pipe (40) close to the inlet housing (54), and a check valve (22) is installed at one end of the communicating pipe (40) close to the outlet pipe (48).

Images