CN114294257A - A kind of static pressure isolation seal assembly and method for double bellows turbine pump - Google Patents

Abstract

The invention provides a static pressure isolation seal assembly and method for a double bellows turbine pump. The assembly includes: a sealing shell, an outer sealing base, an inner sealing base, an outer bellows, an inner bellows, a static ring seat, a static ring, and a dynamic ring; the static ring has a static ring with an annular groove and an air hole. The sealing end face; the inner bellows is sleeved on the inner side of the outer bellows, and an isolated air passage is formed in the middle; the moving ring has a sealing end face, the sealing end face of the moving ring is opposite to the sealing end face of the static ring, and the sealing end face of the moving ring is on the sealing end face of the static ring. The orthographic projection covers all the annular grooves; the isolation gas acts on the sealing end face of the static ring of the static ring and the sealing end face of the moving ring of the moving ring through the gas passage to make it open to form a gas film. The isolation and sealing of the medium on both sides is realized by the sealing end face leading to both ends. The invention can reduce the size of the isolation seal, and at the same time better improve the life and performance of the isolation seal of the turbo pump.

Description

A kind of static pressure isolation seal assembly and method for double bellows turbine pump

technical field

The invention relates to the technical field of construction machinery, in particular to a static pressure isolation sealing assembly and a method for a double bellows turbine pump.

Background technique

In the field of construction machinery, the demand for seals is extremely high, and the use scenarios are very rich. At the same time, due to the increasingly high precision requirements of machinery, the performance requirements for seals are also getting higher and higher, especially for turbo pumps. The working conditions are harsh and the sealing index is strict. Therefore, how to ensure the isolation performance and size optimization of the turbo pump seal is an urgent problem to be solved for those skilled in the art.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide a static pressure isolation seal assembly and method for a double bellows turbine pump, so as to ensure the isolation seal performance of the turbine pump.

On the one hand, an embodiment of the present invention provides a static pressure isolation seal assembly for a double bellows turbo pump, which is used in a turbo pump. The static pressure isolation seal for a double bellows turbo pump includes: a sealing shell, an outer seal Base, inner sealing base, outer bellows, inner bellows, static ring seat, static ring and moving ring; of which:

The sealing shell is fixedly connected to the bottom of the outer sealing base, the outer sealing base is fixedly connected to the bottom of the inner sealing base, and the outer sealing base has a raised edge to connect with the lower end of the bellows. Fixed connection; the outer layer bellows is sleeved on the outside of the inner layer bellows, and an isolated air channel is formed in the middle after sleeve; the outer layer sealing base is provided with a first air inlet through hole, one end of which is connected to the outer layer cavity. The air passage is communicated, and the other end is communicated with the isolation air passage; the static ring seat has a static ring space, and is provided with a second air inlet through hole; an air inlet groove is left on the inner surface of the static ring space; the The static ring seat is fixedly connected with the inner layer corrugated pipe and the upper end of the outer layer corrugated pipe;

The static ring is placed in the static ring space of the static ring seat, and the static ring is fastened to the static ring seat; one end of the static ring has a static ring sealing end face, and the static ring sealing end face is provided with a a pressure-stabilizing groove; an air hole is formed under the pressure-stabilizing groove; the static pressure groove is an annular groove belt, and the air hole under the pressure-stabilizing groove is in the same radial position as the air groove in the static ring space; one end of the dynamic ring It has a sealing end face of the movable ring, and the sealing end face of the static ring is opposite to the sealing end face of the movable ring;

The sealing shell, the outer sealing base, the inner sealing base, the outer bellows, the inner bellows, the static ring seat and the static ring together form a static ring assembly, and the static ring assembly is fixed in the working cavity, so The movable ring is fixed to the transmission shaft, and is sandwiched between the transmission shaft and the positioning shaft sleeve, and the movable ring has a sealing end face, the static ring has a sealing end face, and the sealing end face of the movable ring is connected to the stationary ring. The sealing face of the ring seal contacts to form a sealing face, and the static ring is provided with a pressure-stabilizing groove and an air hole;

The outer layer sealing base is provided with a first air inlet through hole, one end of which is communicated with the air inlet hole of the outer layer cavity, and one end is communicated with the isolated air passage, and the isolated air passage is sleeved on the outer layer bellows. a channel formed in the middle behind the outer side of the inner layer corrugated pipe;

The static ring seat is provided with a second air intake through hole and an air groove, one end of the second air intake through hole is communicated with the isolated air passage, and one end is communicated with the air groove, and the air groove is the second air intake through hole. an annular groove band above the hole, the radial position of the air groove is the same as that of the static ring air hole;

In addition, when the moving ring is in a static state, the sealing end face of the static ring is in close contact with the sealing end face of the moving ring, the first air inlet through hole of the outer seal base and the isolation air passage, the The two air inlet through holes and the air groove of the static ring seat form a gas passage, and the isolation gas is transported to the air hole of the static ring, so that the isolation gas acts on the sealing end face of the static ring and the sealing end face of the static ring through the pressure stabilization groove. The sealing end face of the movable ring produces a static pressure effect, so that the sealing end face of the stationary ring and the sealing end face of the movable ring are opened. The sealing end face is opened to form a gap under the static pressure of the isolation gas, so that the inflow gap lubricates the sealing end face of the static ring and the sealing end face of the moving ring, so that the isolation gas leads to the inner and outer sides, and the isolation The gas isolates and seals the medium on both sides.

Optionally, the static ring seal assembly further includes: an inner damping band and an outer damping band; wherein the outer sealing base has an upper convex edge, and the inner wall of the upper convex edge is provided with a first snap groove , the inner damping belt is clamped in the first clamping groove; the inner wall of the sealing shell is provided with a second clamping groove, and the outer damping belt is clamped in the second clamping groove .

Optionally, the pressure-stabilizing groove is an annular groove belt with a rectangular cross-section, and the position of the pressure-stabilizing groove satisfies that the sum of the outer diameter and the inner diameter is equal to the sum of the inner diameter and the outer diameter of the end face of the static ring seal. The width of the pressure groove is greater than or equal to the diameter of the air hole of the static ring, and the depth is greater than or equal to 0.1 mm.

Optionally, the movable ring adopts cemented carbide or surface spraying technology, or adopts cemented carbide processing, so as to ensure the surface hardness of the sealing end face of the movable ring.

Optionally, a small-diameter throttle nozzle is embedded in the air hole below the pressure-stabilizing groove on the static ring;

Optionally, the number of the air holes is at least 2, and the air holes are evenly distributed under the pressure-stabilizing groove on the static ring;

Optionally, the number of the first air inlet through holes of the outer layer sealing base is at least 2, and the first air inlet through holes are uniformly arranged on the outer layer sealing base;

Optionally, the difference between the inner diameter of the outer layer corrugated pipe and the outer diameter of the inner layer corrugated pipe is greater than or equal to 2 mm.

It can be seen that by setting the outer bellows on the outside of the inner bellows to form an isolated air channel, and using the metal welded bellows as the elastic element, the example of the present invention can be used in ultra-low temperature media, and only one set of seals is used. The isolation effect that can only be achieved by multiple sets of paired seals can be achieved, which greatly saves the space occupied by the seal. In addition, when the moving ring is stationary, static pressure can be generated by introducing the isolation gas, so that the sealing end face of the moving ring and the sealing end face of the static ring can be opened, so that the isolation gas can be used to achieve the isolation of the medium on both sides by means of air sealing. sealing effect. At the same time, due to the introduction of the isolation gas, no matter whether the speed of the main shaft pump reaches the preset speed, it can effectively prevent the media on both sides from meeting and leaking. Isolate the air film, so as to better ensure the lubrication performance between the sealing surfaces and prolong the service life of the sealing components.

On the other hand, the present invention discloses a static pressure isolation sealing method for a double bellows turbine pump, comprising:

① Fix the static ring assembly in the sealing assembly in the outer cavity, and connect the first air inlet through hole of the outer sealing base in the sealing assembly with the air inlet channel of the outer cavity;

②The outer layer bellows in the sealing assembly is sleeved on the outside of the inner layer bellows in the sealing assembly, and an isolated air passage is formed between the inner layer bellows and the outer layer bellows;

③ The movable ring in the sealing assembly is sandwiched between the transmission shaft and the positioning sleeve, the sealing end face of the movable ring in the sealing assembly is in close contact with the sealing end face of the static ring in the sealing assembly, and the sealing assembly is made The inner layer bellows in the sealing assembly is compressed with the outer layer bellows in the sealing assembly;

④ In the static ring assembly in the sealing assembly, the first air inlet through hole of the outer sealing base in the sealing assembly and the outer bellows in the sealing assembly are sleeved inside the sealing assembly. The outer side of the layer bellows is formed with an isolation air passage, the second inlet through hole of the static ring seat in the sealing assembly, the static ring air hole in the sealing assembly, and the pressure-stabilizing groove in the sealing assembly to form a gas passage, and the isolation gas The outer cavity enters through the gas passage, and acts between the sealing end face of the static ring in the sealing assembly and the sealing end face of the moving ring, so that the sealing end face of the static ring in the sealing assembly and the sealing end face of the sealing assembly The sealing end face of the moving ring is opened, and flows to both sides respectively to achieve end face lubrication and block the media on both sides.

Description of drawings

Various other advantages and locations will become apparent to those skilled in the art upon reading the following detailed description of the preferred embodiments. The drawings are for the purpose of illustrating preferred embodiments only and are not to be considered limiting of the invention. Also, the same components are denoted by the same reference numerals throughout the drawings. In the attached image:

1 is a schematic structural diagram of a static pressure isolation seal assembly for a double bellows turbine pump provided by an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a static ring in an isolation seal assembly for a double bellows type turbo pump provided by an embodiment of the present invention.

Detailed ways

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be more thoroughly understood, and will fully convey the scope of the present disclosure to those skilled in the art.

The following first describes the static pressure isolation seal assembly for a double bellows turbine pump provided by the embodiment of the present invention.

Referring to FIG. 1 , the figure shows a schematic structural diagram of a static pressure isolation seal assembly for a double bellows type turbo pump provided by an embodiment of the present invention. As shown in FIG. 1 , the seal assembly is used in a turbo pump, which includes a drive shaft 1 . In the example of the present invention, the static pressure isolation seal assembly for a double bellows turbine pump includes: an inner seal base 2, an outer seal base 3, an inner bellows 4, an outer bellows 5, a static ring seat 6, a static Ring 7 (static ring 7 as compensation ring), dynamic ring 8, positioning bushing 9, small aperture throttle nozzle 10, inner damping belt 11, outer damping belt 12, sealing shell 13.

Wherein, the inner layer corrugated pipe 4 and the outer layer corrugated pipe 5 may be metal welded corrugated pipes with different cross-sectional shapes, which will not be listed one by one here.

In the embodiment of the present invention, the moving ring 8 can be fixed at a fixed position on the transmission shaft 1 by methods including but not limited to interference fit, the moving ring 8 is sandwiched between the transmission shaft 1 and the positioning sleeve 9, and the moving ring 8 has a movable ring sealing end face 81 (specifically located on the left side of the movable ring 8 in FIG. 1 ), and the surface of the movable ring sealing end face 81 is surface sprayed to increase the surface hardness.

The static ring 7 has a static ring sealing end face 71 (specifically located on the right side of the static ring 7 in FIG. 1 ). The static ring 7 is provided with an air hole 400 , and the air hole 400 is matched with the small-diameter throttle nozzle 10 . As shown in FIG. 2 , the static ring A pressure-stabilizing groove 72 is opened on the sealing end surface 71 .

In specific implementation, the pressure-stabilizing groove 72 needs to satisfy that the sum of the inner and outer diameters of the pressure-stabilizing groove 72 is equal to the sum of the inner and outer diameters of the static ring 7 .

Specifically, the number of air holes 400 is at least 2, and they are placed under the pressure-stabilizing groove 72, and are evenly distributed; the outer diameter of the small-diameter throttle nozzle 10 is embedded in the air holes 400. The embodiment of the present invention has no effect on the width and position of the pressure-stabilizing groove. , The specific value of the diameter of the air hole and the size of the small aperture throttling nozzle is not limited.

The bottom of the air hole 400 is opposite to the air groove on the inner surface of the static ring space of the static ring seat 6, the air groove is an annular groove band, and below the air groove is a second air inlet through hole 300, and one end of the second air inlet through hole 300 is communicated with the air groove, The other end communicates with the isolation airway 200 .

The outer sealing base 3 is provided with at least two first air inlet through holes, and at least two first air inlet through holes are evenly arranged on the outer sealing base, and one end of the first air inlet through hole is connected to the outer layer cavity. The body air intake passage 100 is communicated with the other end of the body air passage 200 .

The difference between the inner diameter of the outer layer corrugated pipe 5 and the outer diameter of the inner layer corrugated pipe 4 is greater than or equal to 2 mm.

The outer layer damping belt 12 is placed in the second snap groove of the sealing cavity 13, the inner layer damping belt 11 is placed in the first snap groove of the upper convex edge of the outer layer sealing base 3, and the outer layer sealing base 3 is sealed with the inner layer The bottom edge of the base 2 is fixedly connected, and the form can be shown as the welding seam 15 in Figure 1. The outer sealing base 3 is fixedly connected to the bottom edge of the sealing cavity 13. The fixed connection can be in the form of welding, as shown by 14 in Figure 1. The embodiments of the invention do not limit any fixed connection form.

The isolation gas is introduced through the air passage 100, and flows into the isolation air passage 200 formed by the inner bellows 4 sleeved on the inner side of the outer bellows 5 through the first inlet through hole on the outer sealing base 3, and then flows into the static ring. The second air inlet through hole and air inlet groove 300 on the seat 6 act on the sealing end face 71 of the static ring through the air hole 400 of the static ring, and flow into the inner and outer sides of the sealing assembly respectively to isolate the media on both sides and realize the isolation and sealing effect.

In order to facilitate the understanding of this solution by those skilled in the art, the processing and assembling process and working principle of the static pressure isolation seal for a double bellows turbine pump provided by the embodiment of the present invention will be described below with reference to FIG. 1 .

In actual processing, the operator can first install the static ring 7 in the static ring space of the static ring seat 6, and then perform the fixed connection between the inner layer bellows 4 and the static ring seat 6, and the inner layer bellows 4 and the inner layer sealing base 2 in turn. , set the outer layer bellows 5 from the lower side to the outside of the inner layer bellows 4, and perform the fixed connection between the outer layer bellows 5 and the static ring seat 6, and pre-place the inner layer damping belt 11 on the outer layer sealing base 3 In the first clamping groove of the convex edge, it is sleeved on the inner layer base 2 from bottom to top, and the fixed connection between the inner layer sealing base 2 and the outer layer sealing base 3, and the outer layer base 3 and the outer layer bellows 5 is performed in turn, The outer layer damping belt 12 is pre-placed in the second snap groove of the sealing cavity 13 , and sleeved on the outer sealing base 3 from the lower side, and the fixed connection of the remaining outer sealing base 3 of the sealing cavity 13 is completed.

After processing, the double bellows type static pressure seal assembly includes a moving ring and a static ring assembly. The static ring assembly is an integral assembly and can be directly placed in the working cavity. The moving ring 8 is placed on the step of the transmission shaft 1, and the other There is a positioning shaft sleeve 9 on the side to press, and it can be seen that the moving ring is reliably fixed in a fixed position, and this sealing structure greatly saves the axial dimension.

When the moving ring 8 is at rest, the sealing end face 81 of the moving ring 8 is in close contact with the sealing end face 71 of the static ring 7, so that the sealing of the media on both sides can be achieved in a static state; The isolation gas is introduced through the air passage 100, flows into the isolation air passage 200 through the first air inlet through hole on the outer base 3, and then flows into the second air inlet through hole and the air groove 300 on the static ring seat 6, The ring air hole 400 acts on the sealing end face 71 of the static ring, so that the sealing end face 81 of the static ring of the static ring 8 and the sealing end face 91 of the moving ring of the moving ring 9 are opened, so that the isolation gas can flow into the inner and outer sides of the sealing assembly respectively to isolate the media on both sides. When the moving ring 8 is running at high speed, the isolation gas forms an ultra-thin lubricating gas film between the static ring sealing end face 81 of the static ring 8 and the moving ring sealing end face 91 of the moving ring 9 to ensure the sealing performance At the same time, the lubricating effect of the gas film on the sealing end face is realized, and the sealing life is improved.

Corresponding to the above disclosed static pressure isolation sealing assembly for a double bellows turbo pump, the present invention also discloses a static pressure isolation sealing method for a double bellows turbo pump, the method at least comprising the following steps:

① Fix the static ring assembly in the sealing assembly in the outer cavity, and connect the first air inlet through hole of the outer sealing base in the sealing assembly with the air inlet channel of the outer cavity;

②The outer layer bellows in the sealing assembly is sleeved on the outside of the inner layer bellows in the sealing assembly, and an isolated air passage is formed between the inner layer bellows and the outer layer bellows;

③ The movable ring in the sealing assembly is sandwiched between the transmission shaft and the positioning sleeve, the sealing end face of the movable ring in the sealing assembly is in close contact with the sealing end face of the static ring in the sealing assembly, and the sealing assembly is made The inner layer bellows in the sealing assembly is compressed with the outer layer bellows in the sealing assembly;

④ In the static ring assembly in the sealing assembly, the first air inlet through hole of the outer sealing base in the sealing assembly and the outer bellows in the sealing assembly are sleeved inside the sealing assembly. The outer side of the layer bellows is formed with an isolation air passage, the second inlet through hole of the static ring seat in the sealing assembly, the static ring air hole in the sealing assembly, and the pressure-stabilizing groove in the sealing assembly to form a gas passage, and the isolation gas The outer cavity enters through the gas passage, and acts between the sealing end face of the static ring in the sealing assembly and the sealing end face of the moving ring, so that the sealing end face of the static ring in the sealing assembly and the sealing end face of the sealing assembly The sealing end face of the moving ring is opened, and flows to both sides respectively to achieve end face lubrication and block the media on both sides.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, provided that these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims (7)

1. A static pressure isolation seal assembly for a double bellows type turbine pump, characterized in that the static pressure isolation seal assembly for the double bellows type turbine pump comprises: a sealing shell, an outer sealing base, an inner sealing base , outer corrugated pipe, inner corrugated pipe, static ring seat, static ring and moving ring; among them, The sealing shell is fixedly connected to the bottom of the outer layer sealing base, the outer layer sealing base is fixedly connected to the bottom of the inner layer sealing base, and the outer layer sealing base is fixedly connected to the lower end of the outer layer bellows, The outer layer sealing base is provided with a first air inlet through hole; the outer layer bellows is sleeved outside the inner layer bellows, and an isolation gas is formed between the inner layer bellows and the outer layer bellows One end of the first air inlet through hole of the outer layer sealing base is communicated with the air inlet channel of the outer layer cavity, and the other end is communicated with the isolated air channel; the static ring seat has a static ring space, and the static ring The seat is provided with a second air intake through hole, and the upper side of the second air intake through hole of the static ring seat is provided with an air intake groove; the static ring seat is fixed with the upper end of the inner layer bellows and the outer layer bellows connect; The static ring is placed in the static ring space of the static ring seat, and the static ring is fixedly connected to the static ring seat; one end of the static ring has a static ring sealing end face, and the static ring sealing end face is provided with a stable a pressure groove; an air hole is formed under the pressure stabilization groove; one end of the moving ring has a sealing end face of the moving ring, and the sealing end face of the static ring is opposite to the sealing end face of the moving ring; the sealing shell and the outer sealing base , The inner sealing base, the outer bellows, the inner bellows, the static ring seat and the static ring together form the static ring assembly; In addition, the static ring assembly cooperates with the outer layer cavity and is in a static state, and the dynamic ring cooperates with the rotor; the first air inlet through hole of the outer layer sealing base does not pass into the isolation gas, then the static ring is in a static state. The end face of the ring seal is closely attached to the end face of the movable ring seal; the first air inlet through hole of the outer seal base is passed through the isolation gas, and the isolation gas passes through the isolation air passage and the second inlet of the static ring seat. The air through hole and the air inlet groove, as well as the static ring air hole and the pressure-stabilizing groove act between the static ring sealing end face and the dynamic ring sealing end face to generate a static pressure effect, so that the static ring sealing end face and the The sealing end face of the movable ring is opened; when the movable ring is stationary, isolation gas is introduced, so that the sealing end face of the static ring and the sealing end face of the movable ring are opened. 2 . The sealing assembly according to claim 1 , wherein the pressure-stabilizing groove is an annular groove band with a rectangular cross-section, and the sum of the outer diameter and the inner diameter of the pressure-stabilizing groove is equal to the static ring seal. 3 . The sum of the inner diameter and the outer diameter of the end face, the width of the pressure stabilization groove is greater than or equal to the diameter of the static ring air hole, and the depth is greater than or equal to 0.1 mm. 3 . The sealing assembly according to claim 1 , wherein at least two air holes are opened under the pressure-stabilizing groove, and the at least two air holes have the same radial position as the pressure-stabilizing groove, and the at least two air holes are located in the same direction as the pressure-stabilizing groove. 4 . Two air holes are evenly arranged under the pressure stabilization tank. 4 . The sealing assembly according to claim 1 , wherein an air groove is formed on the inner surface of the static ring space of the static ring seat, the air groove is an annular groove band, and the radial position of the air groove is the same as that of the air groove. 5 . Corresponding to the air holes of the static ring, one end of the second air inlet through hole on the static ring seat is communicated with the air groove, and the other end is communicated with the isolated air passage. 5 . The sealing assembly according to claim 1 , wherein the outer sealing base is provided with at least two first air inlet through holes, and the at least two first air inlet through holes are in the outer layer. 6 . The sealing bases are evenly arranged, and the first air inlet holes are arranged. 6 . The sealing assembly according to claim 1 , wherein the difference between the inner diameter of the outer bellows and the outer diameter of the inner bellows is greater than or equal to 2 mm. 7 . 7. A method for static pressure isolation and sealing for a double bellows type turbine pump, characterized in that, applied to the static pressure isolation seal assembly for a double bellows type turbine pump as described in any one of claims 1 to 6, the said Methods include: ① Fix the static ring assembly in the sealing assembly in the outer cavity, and connect the first air inlet through hole of the outer sealing base in the sealing assembly with the air inlet channel of the outer cavity; ②The outer layer bellows in the sealing assembly is sleeved on the outside of the inner layer bellows in the sealing assembly, and an isolated air passage is formed between the inner layer bellows and the outer layer bellows; ③ The movable ring in the sealing assembly is sandwiched between the transmission shaft and the positioning sleeve, the sealing end face of the movable ring in the sealing assembly is in close contact with the sealing end face of the static ring in the sealing assembly, and the sealing assembly is made The inner layer bellows in the sealing assembly is compressed with the outer layer bellows in the sealing assembly; ④ In the static ring assembly in the sealing assembly, the first air inlet through hole of the outer sealing base in the sealing assembly and the outer bellows in the sealing assembly are sleeved inside the sealing assembly. The outer side of the layer bellows is formed with an isolation air passage, the second inlet through hole of the static ring seat in the sealing assembly, the static ring air hole in the sealing assembly, and the pressure-stabilizing groove in the sealing assembly to form a gas passage, and the isolation gas The outer cavity enters through the gas passage, and acts between the sealing end face of the static ring in the sealing assembly and the sealing end face of the moving ring, so that the sealing end face of the static ring in the sealing assembly and the sealing end face of the sealing assembly The sealing end face of the moving ring is opened, and flows to both sides respectively to achieve end face lubrication and block the media on both sides.

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