CN215762223U - Novel double-screw pump - Google Patents

Abstract

The utility model relates to a novel double-screw pump, which comprises a pump body, wherein an inner lining cylinder is arranged in the pump body, an outflow flow channel is formed between the inner lining cylinder and the inner lining cylinder, double screws are arranged in the inner lining cylinder, and fluid enters the inner lining cylinder through the outflow flow channel and is discharged from the middle part of the inner lining cylinder; through the arrangement of the partition plate, the convection of fluid in the left direction and fluid in the right direction is avoided, and the kinetic energy of the fluid is kept; the flaring extrusion structure is formed between the double screws, so that liquid is extruded from the liquid, and the liquid is discharged conveniently; by arranging the annular supporting plate, the outer flow channel is divided into a plurality of flow dividing channels, so that liquid is more uniformly dispersed at two ends of the lining cylinder, and more liquid enters the lining cylinder and is extruded by the double screws; through the mode of atmospheric pressure seal, can monitor the sealed condition. The utility model achieves the following beneficial effects: the double-screw pump has the advantages of keeping good kinetic energy of fluid, improving the fluid discharge speed, being stable and reliable in structure, high in utilization efficiency of the double screws and capable of monitoring the sealing condition, thereby improving the performance of the whole pump.

Description

Novel double-screw pump

Technical Field

The utility model relates to the technical field of pumps, especially a novel double-screw pump.

Background

The double-screw pump consists of two screw shafts rotating in opposite directions, and each screw shaft is provided with a rotating sleeve with opposite rotating directions. During the operation of the pump, the rotating sleeves on the two screw shafts are meshed with each other and form a sealing cavity with the inner cavity of the pump body, along with the rotation of the screw shafts, gas-liquid mixture in the sealing cavity moves axially along with the sealing cavity, the gas-liquid mixture is stably and continuously conveyed to the outlet of the pump body at the center, and meanwhile, vacuum is formed at the inlet of the pump body, so that liquid is continuously sucked in, and the capacity of conveying liquid is achieved.

The existing twin-screw pump has many defects, such as convection interference, unsatisfactory utilization rate of the screw sleeve, poor discharge effect and poor sealing effect. The design of these pumps in detail is very rough, resulting in the performance of the entire pump being affected.

The company carries out detailed design aiming at the defects, and improves the performance of the whole pump under the condition of not greatly changing the structure of the whole pump.

SUMMERY OF THE UTILITY MODEL

The utility model aims to overcome the defects of the prior art and provide a novel double-screw pump which can keep good kinetic energy of fluid, improve the fluid discharge speed, has stable and reliable structure and high utilization efficiency of double screws and can monitor the sealing condition.

The purpose of the utility model is realized by the following technical scheme: a novel double-screw pump comprises a pump body, wherein an inner lining cylinder is arranged in the pump body, a double-screw rod is arranged in the inner lining cylinder, the double-screw rod extrudes liquid from two ends of the inner lining cylinder to the middle part of the inner lining cylinder, and the middle part of the inner lining cylinder is communicated with a discharge cylinder;

the partition plate cuts off the lining cylinder and divides the lining cylinder into a left cylinder and a right cylinder;

the double-screw rod penetrates through the partition plate;

when the liquid is extruded to the middle position of the lining cylinder from the two ends of the lining cylinder, left direction fluid and right direction fluid are formed; the baffle plate separates the left direction fluid from the right direction fluid to prevent the two from convection.

Furthermore, an outer flow cavity channel is formed between the pump body and the inner lining cylinder and communicated with the feeding cylinder; one end of the discharge cylinder is communicated with the middle part of the lining cylinder, and the other end of the discharge cylinder penetrates out of the wall of the pump body.

Furthermore, a reinforcing edge is vertically welded at the outer contour edge of the partition plate; the reinforcing edge is attached to the inner wall of the lining cylinder; after the partition plate and the reinforcing edge are cut along the axial direction of the double-screw rod, the partition plate and the reinforcing edge are in a T shape. The T-shaped reinforcing edge is arranged, so that the contact area between the partition board and the lining barrel is increased, and the stability of the partition board after installation is ensured.

Furthermore, the lining cylinder consists of an upper half cylinder and a lower half cylinder, and the clapboard consists of an upper plate and a lower plate; the upper plate is arranged on the upper half cylinder through a tenon and a tenon-shaped groove; the lower plate is arranged on the lower half cylinder through another tenon and another tenon-shaped groove. The tenon and the tenon-shaped groove are convenient for the firm installation between the partition board and the lining barrel, thereby further ensuring the stability of the partition board.

Furthermore, a flaring extrusion structure is formed in the middle of the double screw liner; the double-screw rod comprises a driven screw rod and a driving screw rod which are meshed through corresponding screw sleeves;

the left rod part of the driven screw is provided with a screw sleeve c, and the right rod part of the driven screw is provided with a screw sleeve d;

on the driving screw, the left rod part of the driving screw is provided with a screw sleeve m, and the right rod part of the driving screw is provided with a screw sleeve n;

the helical casing c and the helical casing d form a spacing cavity A at the middle part of the driven screw rod;

at the middle part of the driving screw, a spacing cavity B is formed by the spiral sleeve m and the spiral sleeve n;

the width of the spacing cavity A is smaller than that of the spacing cavity B, and a flaring extrusion structure is formed; the liquid pressure at the spacing cavity A is greater than the liquid pressure at the spacing cavity B.

Furthermore, a plurality of annular supporting plates are sleeved on the lining cylinder; the annular supporting plate is abutted against the inner wall of the pump body; the annular supporting plates are arranged in parallel to each other to divide the outer flow cavity into a plurality of flow dividing channels; the liquid flowing in through the feeding cylinder flows to the two ends of the lining cylinder through different flow dividing channels.

In the traditional arrangement mode of the lining cylinder, when liquid is reserved to two ends of the lining cylinder from an outer flow cavity channel, the liquid flow rate of the side, close to the feeding cylinder, of the lining cylinder is large, and the liquid flow rate of the side, far away from the feeding cylinder, of the lining cylinder is small; so that the twin screw is not particularly ideal for the liquid to be extruded to enter when extrusion is performed. The annular supporting plate is divided into a plurality of flow dividing channels by the outer flow cavity, liquid can be relatively uniform no matter the inner lining cylinder is close to or far away from the feeding cylinder, entering of the liquid to be extruded is guaranteed to be as much as possible, and therefore the efficiency of the whole pump is improved.

Furthermore, two ends of the double screw are matched and installed with the pump body through a bearing and a mechanical seal; the mechanical seal comprises a rubber sleeve, a sealing ring and an inflatable ring; the rubber sleeve is fixedly sleeved on the double screw; the sealing ring is sleeved on the rubber sleeve, and the inflatable ring is sleeved on the sealing ring; the sealing ring is pressed on the rubber sleeve by the air pressure of the inflatable ring, so that sealing is realized.

Further, an air nozzle and a pressure gauge are arranged on the surface of the pump body; the air tap is connected with the inflatable ring through an air pipe; the air pipe is also connected with a pressure gauge.

The traditional mechanical seal is realized by simply pressing a seal ring through a compression spring, but the elastic elasticity cannot be monitored after long-term operation. According to the scheme, the sealing ring is extruded in an air pressure mode, and the air pressure can be monitored through the pressure gauge; when the air pressure can not meet the sealing requirement, the sealing device can be realized in an air inflation mode.

Preferably, the mechanical seal further comprises a gland and an arc-shaped pressure plate; the pump body is provided with an annular groove, and a sealing ring and an inflation ring are arranged in the annular groove; the gland presses the sealing ring in the annular groove from the side; the plurality of arc-shaped pressing plates are sleeved on the sealing ring after being connected through the springs; the arc-shaped pressing plate is positioned between the inflatable ring and the sealing ring.

And a plurality of arc-shaped pressure plates 16 are connected through springs and then hooped at the outer ring of the sealing ring 13, so that even if the inflatable ring 14 is broken, a good sealing effect can be still maintained.

It should be noted that, in the double-screw rod, the driven screw and the driving screw are parallel to each other, one end of the driving screw is driven by the motor, and the other end is connected with the driven screw by the gear.

It should be noted that the spiral sleeve c on the driven screw is meshed with the spiral sleeve m on the driving screw; the screw sleeve d on the driven screw is meshed with the screw sleeve n of the driving screw. The rotating direction of the spiral sleeve c is opposite to that of the spiral sleeve m; the rotation direction of the screw sleeve m is opposite to that of the screw sleeve n.

It should be noted that the liquid in this embodiment is only one of the fluids.

The utility model has the following advantages:

(1) the partition plate is arranged to separate the left fluid from the right fluid, so that convection (hedging) between the two fluids is avoided, kinetic energy consumption is avoided, and the fluid with good kinetic energy is discharged at a high speed;

(2) the reinforcing edge is arranged at the edge of the outer contour of the partition plate, so that the contact area between the partition plate and the inner wall of the lining barrel is increased, the partition plate is prevented from shaking under the impact of fluid, and the stability is improved; the partition board is also arranged with the lining barrel through the tenon and the tenon groove, so that the firmness is further ensured;

(3) the width of the spacing cavity A is smaller than that of the spacing cavity B, the number of the screw sleeves on the driven screw rod is smaller than that of the screw sleeves on the driving screw rod, and the purpose is to enable the liquid pressure at the spacing cavity A to be larger than that of the spacing cavity B, enable the liquid at the spacing cavity A to extrude the liquid at the spacing cavity B and enable the liquid to be discharged better; namely forming a flaring extrusion structure;

(4) in the traditional pump structure, a large amount of liquid (fluid) is concentrated at a certain position (close to the side of the feeding cylinder) at two ends of the lining cylinder, and the liquid cannot well enter the lining cylinder; in the scheme, the annular supporting plate is arranged to divide a traditional outflow channel into a plurality of flow dividing channels, so that liquid flows from the flow dividing channels, the liquid is dispersed at a plurality of positions at two ends of the lining cylinder, more liquid can enter the lining cylinder in the same time period, and the extrusion efficiency of the double-screw rod is improved;

(5) the traditional mechanical seal is realized by a pressure spring, and the pressure spring cannot be monitored and can only be replaced according to experience and time when the elastic performance is changed due to long-time use; the scheme is provided with the air pressure ring and the sealing ring, sealing is achieved through the air pressure mode, the air pressure condition can be monitored, pressurization can be achieved at any time, and sealing can be guaranteed constantly.

Drawings

FIG. 1 is a schematic view of the present invention with a baffle plate;

FIG. 2 is a schematic view of the present invention with a spacer, flare extrusion configuration;

FIG. 3 is a schematic view of the present invention with the baffle, flare pressing structure, annular support plate;

FIG. 4 is a schematic cross-sectional view of the pump body, the partition plate, the liner, the driven screw, and the driving screw;

FIG. 5 is a schematic cross-sectional view of the arrangement among the liner, the partition, the driven screw, and the driving screw;

FIG. 6 is a schematic view of the structure of the separator;

FIG. 7 is a schematic view of the construction of the liner;

FIG. 8 is a schematic structural view of the annular support plate;

FIG. 9 is a schematic view of a mechanical seal arrangement;

FIG. 10 is an enlarged view of FIG. 9;

FIG. 11 is a schematic view of the arrangement of the respective helical casings on the twin screws;

in the figure: 1-pump body, 101-outer flow cavity channel, 2-driven screw, 3-driving screw, 4-screw sleeve, 401-screw sleeve c, 402-screw sleeve d, 403-screw sleeve m, 404-screw sleeve n, 5-inner lining barrel, 6-clapboard, 7-feeding barrel, 8-discharging barrel, 9-reinforcing edge, 10-annular supporting plate, 1001-notch E, 1002-notch F, 11-diversion channel, 12-rubber sleeve, 13-sealing ring, 14-inflation ring, 15-gland, 16-arc-shaped pressure plate, 17-air nozzle, 18-pressure gauge and 19-reinforcing edge.

Detailed Description

The utility model will be further described with reference to the accompanying drawings, but the scope of the utility model is not limited to the following.

As shown in fig. 1, a novel twin-screw pump comprises a pump body 1, wherein the pump body 1 is supportingly provided with an inner lining tube 5, a twin-screw is arranged in the inner lining tube 5, and a corresponding screw sleeve 4 is sleeved on the twin-screw; an outer flow cavity channel 101 is formed between the inner lining cylinder 5 and the pump body 1, the feeding cylinder 7 is communicated with the outer flow cavity channel 101 from the rear wall of the pump body 1, the middle part of the inner lining cylinder 5 is communicated with the discharging cylinder 8, and the discharging cylinder 8 penetrates out from the front wall of the pump body 1.

When the double-screw rod rotates, liquid at two ends of the lining cylinder 5 is extruded towards the middle of the lining cylinder 5, and finally discharged from the discharging cylinder 8. When the liquid at both ends of the inner liner 5 enters the inner liner 5, the water pressure of the outer flow channel 101 is reduced, so that the liquid at the inlet cylinder 7 flows into the outer flow channel 101.

It should be noted that the same features as the present embodiment also exist in a double screw pump of a general design, as shown in fig. 11: the double screw rods comprise a driven screw rod 2 and a driving screw rod 3 which are parallel, one end of the driving screw rod 3 is driven by a motor, and the other end of the driving screw rod 3 is connected with the driven screw rod 2 in a driving way through a gear; secondly, a left rod part of the driven screw rod 2 is provided with a spiral sleeve c401, and a right rod part of the driven screw rod is provided with a spiral sleeve d 402; the left rod part of the driving screw rod 3 is provided with a screw sleeve m403, and the right rod part thereof is provided with a screw sleeve n 404; at the middle part of the driven screw 2, a space cavity A is formed by the spiral sleeve c401 and the spiral sleeve d 402; at the middle part of the driving screw rod 3, a spacing cavity B is formed by a spiral sleeve m403 and a spiral sleeve n 404; thirdly, the spiral sleeve c401 is meshed with the spiral sleeve m; the spiral sleeve d is meshed with the spiral sleeve n; the rotating direction of the spiral sleeve c is opposite to that of the spiral sleeve m; the rotation direction of the screw sleeve m is opposite to that of the screw sleeve n.

In this embodiment, as shown in fig. 1, the partition plate 6 is provided, and the partition plate 6 cuts the liner 5 and divides the liner 5 into a left tube and a right tube. And the double-screw rod passes through the partition plate 6, and the partition plate 6 is positioned at the positions of the spacing cavity A and the spacing cavity B.

When the double screw rod rotates, the liquid (fluid) at the left end and the right end of the lining cylinder 5 is extruded to the spacing cavity A and the spacing cavity B through the corresponding screw sleeves 4. When the liquid (fluid) at the left and right ends of the left inner liner 5 flows toward the middle, a left direction fluid and a right direction fluid are formed. And the arrangement of the partition plate 6 prevents the fluid from flowing in the left direction and the fluid from flowing in the right direction, keeps good kinetic energy of the fluid and improves the discharge power of the pump. The traditional arrangement without the partition plate 6 can cause liquid (fluid) to generate convection, and kinetic energy can be offset when the liquid (fluid) is convected, so that the flow rate of the liquid is influenced, and the pump power is not ideal enough.

In the embodiment, as shown in fig. 1, a reinforcing edge 19 is vertically welded at the outer contour edge of the partition plate 6; the reinforcing edge 19 is attached to the inner wall of the lining cylinder 5; after the partition plate 6 and the reinforcing edge 19 are cut along the axial direction of the double-screw rod, the two are in a T shape. The arrangement of the reinforcing edge 19 increases the contact area between the outer contour edge of the partition plate 6 and the lining cylinder 5, thereby ensuring the stability of the partition plate 6 and avoiding the left and right shaking under the impact of liquid.

Further, as shown in fig. 5 to 7, the lining cylinder 5 is composed of an upper half cylinder and a lower half cylinder, and the partition plate 6 is composed of an upper plate and a lower plate; the upper plate is arranged on the upper half cylinder through a tenon 9 and a tenon-shaped groove; the lower plate is mounted on the lower half cylinder through another tenon 9 and another tenon-shaped groove.

During assembly, the upper plate and the lower plate of the clapboard 6 are clamped in the middle of the double-screw rod; then the partition board 6 is clamped by the upper half cylinder and the lower half cylinder of the lining cylinder 5, the tenon 9 is butted with the tenon-shaped groove, the reinforcing edge 19 is contacted with the inner wall of the lining cylinder 5, and the firmness of the partition board 6 after installation is further ensured.

Still further, the cross section of the lining tube 5 is in a horizontal and flat shape of "8", and the partition plate 6 is also in a horizontal and flat shape of "8".

Alternatively, as shown in fig. 2, in the inner liner 5, the driving screw 3 is close to the side of the discharging cylinder 8, and the driven screw 2 is far from the side of the feeding cylinder 7; and the width of the spacing cavity A in the middle of the driven screw rod 2 is smaller than that of the spacing cavity B in the middle of the driving screw rod 3.

The effect is: the widths of the spacing cavities A and the spacing cavities B are set so that the liquid pressure at the spacing cavities A is greater than the liquid pressure at the spacing cavities B. I.e. the high-pressure liquid in the space cavity a, produces an extrusion to the lower-pressure liquid in the space cavity B, thereby facilitating the discharge of the liquid in the space cavity B from the discharge cylinder 8.

In the embodiment, the number of the screw sleeves 4 on the driven screw 2 is more than that of the screw sleeves 4 on the driving screw 3; further, the liquid pressure in the space A is made larger than that in the space B.

Alternatively, a new twin-screw pump, as shown in fig. 3, 4 and 8, the inner liner 5 is sleeved with a plurality of annular support plates 10, and the annular support plates 10 are supported against the inner wall of the pump body 1.

In the scheme, the annular supporting plates 10 are parallel to each other, and a shunting flow passage 11 is formed at the parallel distance. And the annular support plate 10 itself, near the infeed chute 7, has a notch E1001 and near the outfeed chute 8 a notch F1002.

The design of the annular support plate 10 divides the liquid flow path of the outflow channel 101 into two paths: in the first route, the liquid in the feeding cylinder 7 flows along the inner wall of the pump body 1 through the notch E1001 and finally flows to the two ends of the lining cylinder 5 at the driven screw 2; in the second route, the liquid in the feed cylinder 7 directly passes through the diversion flow channel 11, surrounds the outer wall of the lining cylinder 5 for a half circle, and finally flows to the two ends of the lining cylinder 5 at the driving screw 3 through the notch F1002.

The two-route design has the advantages that the liquid is divided equivalently, and the liquid at the two ends of the lining cylinder 5 is ensured not to be concentrated at one position in a large quantity, but is dispersed at the positions of the two ends of the driven screw rod 2 and the driving screw rod 3. Compared with the traditional mode of only concentrating at two ends of the driven screw rod 2, the scheme can enable more liquid to be extruded by the double-screw rod.

In a conventional double screw pump, the flow direction of the fluid (liquid) should be: the feed cylinder 7 → both ends of the liner cylinder 5 at the driven screw 2 → both ends of the liner cylinder 5 at the driving screw 3 → flows toward the middle. That is, the fluid at the two ends of the lining tube 5 at the driving screw 3 must be firstly positioned at the two ends of the lining tube 5 at the driven screw 2; this causes the flow rate at both ends of the lining tube 5 at the driving screw 3 to be greater than the flow rate at both ends of the lining tube 5 at the driving screw 3, so that the driving screw 3 cannot be sufficiently extruded.

Preferably, the diversion flow channel 11 is in a shape of a Chinese character 'ba' at the notch E1001.

Alternatively, a novel twin screw pump is shown in fig. 3 and 9, wherein both ends of the twin screw are assembled on the pump body 1 through bearings and mechanical seals.

In this embodiment, the mechanical seal includes a rubber sleeve 12, a sealing ring 13, and an air-filled ring 14; the rubber sleeve 12 is fixedly sleeved on the double screw; a sealing ring 13 is sleeved on the outer ring side of the rubber sleeve 12, and an inflatable ring 14 is sleeved on the outer ring side of the sealing ring 13; the air-filled ring 14 presses the sealing ring 13 on the rubber sleeve 12 through air pressure to realize sealing.

The air charging ring 14 is also connected with an air nozzle 17 through an air pipe, and the air pipe is also connected with a pressure gauge 18; an air tap 17 and a pressure gauge 18 are both arranged at the surface of the pump body 1.

In the scheme, the pressure condition in the inflatable ring 14 is observed through the pressure gauge 18; when the pressure is less than the set value, the air is inflated through the air nozzle 17, and good pressure in the air inflation ring 14 is ensured. The traditional mechanical seal is realized through a pressure spring, when the elasticity of the pressure spring changes due to long-term use, the pressure condition cannot be monitored, the sealing condition cannot be monitored, and it is unclear when the pressure spring is replaced.

Further, the rubber sleeve 12 is fixed to the twin screw by screws. An annular groove is formed in the inner wall of the pump body 1, and the sealing ring 13 and the inflating ring 14 are arranged in the annular groove.

Further, as shown in fig. 10, the mechanical seal further includes a gland 15 and an arc-shaped pressure plate 16. The gland 15 laterally abuts the sealing ring 13 in the annular groove; the plurality of arc-shaped pressing plates 16 are connected through springs and then sleeved on the sealing ring 13; an arcuate pressure plate 16 is located between the inflatable ring 14 and the sealing ring 13. Even if the inflatable ring 14 is broken, the spring still can maintain good sealing effect.

The above examples only represent preferred embodiments, and the description thereof is more specific and detailed, but not to be construed as limiting the scope of the utility model. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.

Claims (9)

1. The utility model provides a novel double-screw pump, includes the pump body (1), is equipped with interior bushing (5) in the pump body (1), is equipped with two screws in interior bushing (5), and two screws extrude the middle part to interior bushing (5) with liquid from the both ends of interior bushing (5), and the middle part and the play feed cylinder (8) of interior bushing (5) are linked together its characterized in that:

the device also comprises a clapboard (6) which cuts off the lining cylinder (5) and divides the lining cylinder (5) into a left cylinder and a right cylinder;

the double-screw rod penetrates through the clapboard (6);

when the liquid is extruded to the middle position of the lining cylinder (5) from the two ends of the lining cylinder (5), left direction fluid and right direction fluid are formed; the baffle (6) separates the left direction fluid from the right direction fluid to prevent the two from convection.

2. A novel twin screw pump according to claim 1, wherein: an outer flow cavity (101) is formed between the pump body (1) and the inner lining cylinder (5), and the outer flow cavity (101) is communicated with the feeding cylinder (7);

one end of the discharge barrel (8) is communicated with the middle part of the lining barrel (5), and the other end of the discharge barrel penetrates out of the wall of the pump body (1).

3. A novel twin screw pump according to claim 1 or claim 2, characterised in that: a reinforcing edge (19) is vertically welded at the outer contour edge of the partition plate (6);

the reinforcing edge (19) is attached to the inner wall of the lining cylinder (5);

after the partition plate (6) and the reinforcing edge (19) are cut along the axial direction of the double-screw rod, the partition plate and the reinforcing edge are in a T shape.

4. A novel twin screw pump according to claim 3, wherein: the lining cylinder (5) consists of an upper half cylinder and a lower half cylinder, and the clapboard (6) consists of an upper plate and a lower plate;

the upper plate is arranged on the upper half cylinder through a tenon (9) and a tenon-shaped groove;

the lower plate is arranged on the lower half cylinder through another tenon (9) and another tenon-shaped groove.

5. A novel twin screw pump according to claim 1 or claim 2, characterised in that: the double screws also form a flaring extrusion structure in the middle of the lining barrel (5);

the double-screw rod comprises a driven screw rod (2) and a driving screw rod (3), and the driven screw rod and the driving screw rod are meshed through corresponding screw sleeves (4);

on the driven screw (2), the left rod part is provided with a screw sleeve c (401), and the right rod part is provided with a screw sleeve d (402);

on the driving screw rod (3), the left rod part of the driving screw rod is provided with a screw sleeve m (403), and the right rod part of the driving screw rod is provided with a screw sleeve n (404);

a space cavity A is formed between the spiral sleeve c (401) and the spiral sleeve d (402) at the middle part of the driven screw rod (2);

at the middle part of the driving screw rod (3), a spiral sleeve m (403) and a spiral sleeve n (404) form a spacing cavity B;

the width of the spacing cavity A is smaller than that of the spacing cavity B; and the liquid pressure at the spacing cavity A is higher than that at the spacing cavity B, so that a flaring extrusion structure is formed.

6. A novel twin screw pump according to claim 1 or claim 2, characterised in that: a plurality of annular supporting plates (10) are sleeved on the lining cylinder (5);

the annular supporting plate (10) is abutted against the inner wall of the pump body (1);

the annular supporting plates (10) are arranged in parallel to each other to divide the outer flow cavity (101) into a plurality of flow dividing channels (11);

the liquid flowing in through the feeding cylinder (7) flows to the two ends of the lining cylinder (5) through different diversion flow channels (11).

7. A novel twin screw pump according to claim 1 or claim 2, characterised in that: two ends of the double screw are respectively matched and installed with the pump body (1) through a bearing and a mechanical seal;

the mechanical seal comprises a rubber sleeve (12), a sealing ring (13) and an inflatable ring (14);

the rubber sleeve (12) is fixedly sleeved on the double screw; a sealing ring (13) is sleeved on the outer ring side of the rubber sleeve (12), and an inflating ring (14) is sleeved on the outer ring side of the sealing ring (13);

the air-filled ring (14) presses the sealing ring (13) on the rubber sleeve (12) through air pressure to realize sealing.

8. A novel twin screw pump according to claim 7, wherein: an air nozzle (17) and a pressure gauge (18) are arranged on the surface of the pump body (1);

the air tap (17) is connected with the inflatable ring (14) through an air pipe; the air pipe is also connected with a pressure gauge (18).

9. A novel twin screw pump according to claim 8, wherein: the mechanical seal also comprises a gland (15) and an arc-shaped pressure plate (16);

an annular groove is formed in the pump body (1), and a sealing ring (13) and an inflation ring (14) are arranged in the annular groove; the gland (15) abuts the sealing ring (13) in the annular groove from the side surface;

the plurality of arc-shaped pressing plates (16) are sleeved on the sealing ring (13) after being connected through the springs; the arc-shaped pressing plate (16) is positioned between the inflatable ring (14) and the sealing ring (13).

Images