CN212455493U

CN212455493U - Two-stage combined type rotating shaft sealing device

Info

Publication number: CN212455493U
Application number: CN202020787204.5U
Authority: CN
Inventors: 王瑞; 赵洋洋
Original assignee: Lanzhou Tianda Huarui Environmental Engineering Technology Co ltd
Current assignee: Lanzhou Tianda Huarui Environmental Engineering Technology Co ltd
Priority date: 2020-05-13
Filing date: 2020-05-13
Publication date: 2021-02-02
Anticipated expiration: 2030-05-13

Abstract

A two-stage combined type rotating shaft sealing device is applied to the technical field of sealing of rotating shafts and comprises a first-stage arch-shaped combined seal and a second-stage packing seal bin; the first-level arch type combined seal comprises: the device comprises an arch sealing gland, a first O-shaped sealing ring, a second O-shaped sealing ring, a medium injection hose and an arch combined sealing cavity; the secondary packing sealed cabin comprises: the device comprises a packing gland, a packing box, a first sealing medium injection hose and an isolation bin nitrogen outlet connecting pipe; the structure is mainly applied to shaft end sealing of low-pressure rotating shaft type equipment in a gas-liquid or liquid-solid mixed phase of a medium in an equipment shell in the petrochemical industry; the two-stage combined type rotary shaft sealing device can achieve the purpose of zero leakage of dangerous media in stirring equipment, and has the advantages of long service life, reliable sealing, simplicity in maintenance, convenience in maintenance and no pollution.

Description

Two-stage combined type rotating shaft sealing device

Technical Field

The utility model provides a two-stage combination formula rotation axis sealing device, is applied to the sealed technical field of rotation axis, concretely relates to axle head seal of low pressure rotation axis formula equipment in the petrochemical industry equipment shell medium is gas-liquid or the solid-liquid mixture phase.

Background

The shaft end seal of low-pressure rotary shaft type equipment in the existing petrochemical industry, wherein the medium in the equipment shell is in a gas-liquid or liquid-solid mixed phase, mainly adopts seal structures such as a floating ring seal, a mechanical seal and the like; the two-stage combined rotary shaft sealing device can achieve the purpose of zero leakage of dangerous media in rotary shaft type equipment, and has the advantages of long service life, reliable sealing, simplicity in maintenance, convenience in overhaul, no pollution and the like. The existing sealing structure similar to the combined sealing device is as follows:

the combined floating ring sealing device (with the patent number of 00132605.8) and the floating ring sealing device (with the patent number of CN1334408A) mainly optimize the limitations of the floating ring sealing device based on the floating ring sealing; the combined floating ring sealing device (patent number 00132605.8) mainly improves the adaptability of the floating ring sealing device to oil-gas pressure difference, enlarges the safe operation range and effectively reduces the internal leakage of sealing oil; a floating ring sealing device (with the patent number of CN1334408A) is provided with a channel which is communicated with an inner hole and an outer wall of an inner floating ring in the annular wall surface of the inner floating ring, thereby effectively reducing the temperature of the inner floating ring and ensuring the safe operation of the sealing device. The sealing structure is mainly suitable for shaft end sealing of turbines, centrifugal compressors and other fluid machines in the industries of petrochemical industry and the like, the technical limitation is that slight leakage of floating ring sealing still exists, and the long-term stable operation of the sealing structure is difficult to realize for equipment needing to realize zero leakage of dangerous media in the shell.

A kind of rotating shaft makes the sealing means up (patent number CN101799075A), this technology belongs to the mechanical seal field, mainly suitable for the liquid seal in the fields such as military project, shipping and navigation, etc., the technical matter that it solves is to seal the liquid under the harsh sealing performance requirements such as low temperature, pollution-free, no leakage, etc.; the technical limitation is that the sealing structure belongs to the field of mechanical sealing, and for liquid-solid mixed phase media, an internal sealing assembly is quickly abraded, so that later-period operation and maintenance costs are high, and the application range of the sealing device is inconsistent with that of the sealing device.

SUMMERY OF THE UTILITY MODEL

The utility model discloses an aim at above-mentioned prior art current situation, provide a two-stage combination formula rotation axis sealing device to solve the problem that provides in the above-mentioned background art.

In order to realize the purpose, the utility model discloses specifically adopt following technical scheme:

a two-stage combined type rotary shaft sealing device mainly comprises a first-stage arch type combined seal a and a second-stage packing seal bin b, wherein the first-stage arch type combined seal a comprises an arch seal gland 4, a first O-shaped seal ring 5, a second seal medium injection hose 6, an arch type combined seal cavity 7, an arch type combined seal cavity fixing seat 8, a special-shaped distribution ring 9, a second O-shaped seal ring 10, a wedge-shaped seal 11, a dust ring 12, an arch type seal 14, a second distribution ring 15, a third seal medium injection hose 16 and a shaft sleeve 22; the secondary packing sealing bin b comprises a packing gland 1, a packing box 2, a first sealing medium injection hose 3, an isolation bin nitrogen outlet connecting pipe 17, a fourth sealing medium injection hose 18, a sealing medium distribution ring 19, a wedge-shaped sealing ring 20, packing 21 and a third O-shaped sealing ring 23.

Furthermore, the dust ring 12 is provided with 2, the arch seal 14 is provided with 4, the 2 dust rings 12 are arranged in parallel in the groove at the front end of the arch combined seal cavity 7, and the 4 arch seals 14 are symmetrically arranged back to back and are respectively arranged at two sides of the second distribution ring 15; 4 arch seals 14 are sequentially arranged in the arch combined seal cavity 7 and are limited and assembled into a whole through the arch seal gland 4, 2V-shaped grooves are arranged on the inner wall of each arch seal 14,

further, a second O-shaped ring 10 is arranged on the circumferential contact surface of the end surface of the special-shaped distribution ring 9 and the arch-shaped combined seal cavity 7 for sealing, a second O-shaped seal ring 10 is also adopted on the circumferential contact surface of the outer ring of the special-shaped distribution ring 9 and the arch-shaped combined seal cavity fixing seat 8, and solid particles are blocked and sealed under the combined action of back flushing of nitrogen introduced through a third seal medium injection hose 16 and spiral back pushing of a shaft sleeve between the inner ring of the special-shaped distribution ring 9 and a rotating shaft.

Preferably, the stuffing box 2 is provided with a nitrogen isolation bin, the nitrogen isolation bin is communicated with the first sealing medium injection hose 3, nitrogen is injected into the nitrogen isolation bin through the first sealing medium injection hose 3, and the nitrogen plays a role in buffering.

Preferably, the arch-shaped combined sealing cavity fixing seat 8 is connected with an end plate of the rotating shaft equipment into a whole through welding or threaded connection, and the verticality between the sealing end face of the arch-shaped combined sealing cavity fixing seat 8 and the center of the rotating shaft equipment is larger than 0.15 mm.

Preferably, the sealing medium injection hose 6 is divided into 3 paths to enter the arch-shaped combined sealing cavity 7, the first path enters the 2 dust rings 12 through the first distribution ring 13 arranged at the front end of the arch-shaped combined sealing cavity 7, the dust rings 12 firstly and effectively block partial solid particles in the equipment, so that the abrasion of impurities and particles to the rear arch-shaped seal 14 is reduced, the second path and the third path enter the second distribution ring 15 through oil injection holes arranged at the middle part and the rear end of the arch-shaped combined sealing cavity 7 to be distributed, the distributed paths enter the middle 2 arch-shaped seal 14 and the rear 2 arch-shaped seal 14 respectively, 2V-shaped grooves are arranged on the inner wall of each arch-shaped seal 14, the grooves are mainly used as a flow passage and a storage space of lubricating grease in the working state of the arch-shaped seal 14, the lubricating grease can conveniently and effectively lubricate the working face of the arch-shaped seal in time, and the elastic deformation performance of the O-shaped sealing ring designed on the back of the arch-shaped seal 14 is used for the lubricating grease to ensure that the working 22 are tightly attached and synchronously compensated along with the continuous abrasion of the working surface of the arch-shaped seal, so as to realize the multi-stage isolation sealing of dangerous media in a rotary shaft equipment shell, a sealing medium distribution ring 19 and a wedge-shaped sealing ring 20 jointly form a wedge-shaped seal combination, firstly, part of solid particles leaked after the sealing failure of the first-stage arch-shaped combination are effectively blocked, so that the abrasion of impurities and particles to a rear-end packing 21 is reduced, sealing gas enters the sealing medium distribution ring 19 through a first sealing medium injection hose 3 to apply pressure to groups of packings distributed behind the sealing medium distribution ring 19, so that the packing compression deformation abraded after operation is always expanded and tightly arranged in a packing cavity formed by the inner wall of the packing 2 and the shaft sleeve 22, and the final effective sealing is carried out on part of lubricating grease leaked from the first-stage arch-shaped combination seal and a small amount of media carried out by the lubricating grease, so as to realize the purpose of zero leakage of dangerous media in the rotary shaft type equipment.

Preferably, the pressure of the sealing gas of the secondary packing sealing bin is higher than the highest working pressure in the shell of the rotating shaft equipment.

Preferably, the stuffing box 2 and the arch-shaped combined sealing cavity fixing seat 8 are fastened by the stuffing box fixing bolt and then are subjected to finish machining, and meanwhile, the concentricity installation of the inner wall of the stuffing box 2 and the center of the rotating shaft equipment is guaranteed.

Preferably, the surface of the shaft sleeve 22 needs to be sprayed with a hard coating, and the surface of the shaft sleeve is polished.

Compared with the prior art, the beneficial effects of the utility model reside in that: the two-stage combined sealing device which is composed of the first-stage arch combined seal, the second-stage packing sealing bin provided with the sealing medium distribution ring and the wedge-shaped sealing ring, the shaft sleeve and the O-shaped sealing ring can achieve the purpose of zero leakage of dangerous media in rotary shaft type equipment, has the advantages of long service life, reliable seal, simplicity in maintenance, convenience in maintenance, no pollution and the like, and overcomes the limitation of the existing sealing device in the use process.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic view of a one-stage arch-shaped combined sealing structure.

Fig. 3 is a structural schematic diagram of a two-stage packing sealed bin provided with a sealing medium distribution ring.

FIG. 4 is a schematic view of an arch seal

In the figure: the device comprises a primary arch type combined seal a, a secondary packing seal bin b, a packing gland 1, a packing box 2, a first sealing medium injection hose 3, an arch type sealing gland 4, a first O-shaped seal ring 5, a second sealing medium injection hose 6, an arch type combined seal cavity 7, an arch type combined seal cavity fixing seat 8, a special-shaped distribution ring 9, a second O-shaped seal ring 10, a wedge-shaped seal 11, a dust ring 12, a first distribution ring 13, an arch-shaped seal 14, a second distribution ring 15, a third sealing medium injection hose 16, an isolation bin nitrogen outlet connecting pipe 17, a fourth sealing medium injection hose 18, a sealing medium distribution ring 19, a wedge-shaped seal ring 20, a packing 21, a shaft sleeve 22 and a third O-shaped seal ring 23.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments.

Example 1

further, a second O-shaped sealing ring 10 is arranged on the circumferential contact surface of the end surface of the special-shaped distribution ring 9 and the arch-shaped combined sealing cavity 7, the circumferential contact surface of the outer ring of the special-shaped distribution ring 9 and the arch-shaped combined sealing cavity fixing seat 8 is also sealed by the second O-shaped ring 10, and the inner ring of the special-shaped distribution ring 9 and the rotating shaft are sealed by blocking solid particles under the combined action of back flushing of nitrogen introduced through a third sealing medium injection hose 16 and spiral back pushing of a shaft sleeve.

Example 2

The stuffing box 2 is provided with a nitrogen isolation bin which is communicated with the first sealing medium injection hose 3, and nitrogen is injected into the nitrogen isolation bin through the first sealing medium injection hose 3 and has a buffering effect.

Example 3

The arch-shaped combined sealing cavity fixing seat 8 is connected with an end plate of the rotating shaft equipment into a whole through welding or threaded connection, and the verticality between the sealing end face of the arch-shaped combined sealing cavity fixing seat 8 and the center of the rotating shaft equipment is larger than 0.15 mm.

Example 4

The sealing medium injection hose 6 is divided into 3 paths to enter the arch-shaped combined sealing cavity 7, the first path enters the 2 dust rings 12 through the first distribution ring 13 arranged at the front end of the arch-shaped combined sealing cavity 7, the dust rings 12 firstly and effectively block partial solid particles in the equipment so as to reduce the abrasion of impurities and particles to the arch-shaped seal 14 at the rear end, the second path and the third path enter the second distribution ring 15 through oil injection holes arranged at the middle part and the rear end of the arch-shaped combined sealing cavity 7 to be distributed, and respectively enter the middle arch-shaped seal 14 and the rear arch-shaped seal 14 after being distributed, the inner wall of each arch-shaped seal 14 is provided with 2V-shaped grooves which are mainly used as a flow passage and a storage space of lubricating grease under the working state of the arch-shaped seal 14, so that the lubricating grease can timely and effectively lubricate the working surface of the arch-shaped seal, thereby prolonging the service life of the arch-shaped seal 14, lubricating oil enables an arch-shaped sealing working surface to be tightly attached to a shaft sleeve 22 through elastic deformation performance of an O-shaped sealing ring designed on the back of an arch-shaped seal 14, synchronous compensation is carried out along with continuous abrasion of the arch-shaped sealing working surface, so that multi-stage isolation sealing blocking is carried out on dangerous media in a rotary shaft equipment shell, a sealing medium distribution ring 19 and a wedge-shaped sealing ring 20 jointly form a wedge-shaped sealing combination, firstly, part of solid particles which leak after the invalidation of the one-stage arch-shaped combination sealing is effectively blocked, so that abrasion of impurities and particles to rear-end packing 21 is reduced, sealing gas enters the sealing medium distribution ring 19 through a first sealing medium injection hose 3 to apply pressure to groups of packing distributed behind the sealing medium distribution ring 19, so that the abrasion packing after operation is compressed and deformed to be always expanded in a packing cavity formed by the inner wall of a packing box 2 and the shaft sleeve 22, and part of lubricating grease leaked by the one-stage arch-type combination sealing, and a small amount of medium carried out by the lubricating grease is finally and effectively sealed, so that the aim of zero leakage of dangerous medium in the rotary shaft type equipment is fulfilled.

Example 5

The pressure of the sealing gas of the secondary packing sealing bin needs to be higher than the highest working pressure in the rotating shaft equipment shell.

Example 6

And the stuffing box 2 and the arch-shaped combined sealing cavity fixing seat 8 are fastened by the stuffing box fixing bolt and then are subjected to finish machining, and meanwhile, the concentricity installation of the inner wall of the stuffing box 2 and the center of the rotating shaft equipment is ensured.

Example 7

The surface of the shaft sleeve 22 needs to be sprayed with a hard coating and polished.

Example 8

The two-stage combined type rotary shaft sealing device belongs to two types of contact type sealing integrated multi-stage combined sealing, and proper lubricating grease and sealing gas (the gas cannot react with the medium in the rotary shaft type equipment and the medium in the downstream equipment or influence the quality of a finished medium product) must be matched, and the selection of the lubricating grease and the sealing gas, the pressure, the flow and other parameters must be adapted to the working condition of the sealed medium.

The above description is only exemplary of the present invention and should not be taken as limiting the scope of the present invention, as any modifications, equivalents, improvements and the like made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.

Claims

1. The utility model provides a two-stage combination formula rotary shaft sealing device, includes that one-level arch form combination is sealed (a), second grade filler sealed storehouse (b), its characterized in that: the primary arch type combined seal (a) comprises: the device comprises an arched sealing gland (4), a first O-shaped sealing ring (5), a second sealing medium injection hose (6), an arched combined sealing cavity (7), an arched combined sealing cavity fixing seat (8), a special-shaped distribution ring (9), a second O-shaped sealing ring (10), a wedge-shaped seal (11), a dust ring (12), an arched seal (14), a second distribution ring (15), a third sealing medium injection hose (16) and a shaft sleeve (22); the secondary packing sealed bin b comprises: the device comprises a packing gland (1), a packing box (2), a first sealing medium injection hose (3), an isolation bin nitrogen outlet connecting pipe (17), a fourth sealing medium injection hose (18), a sealing medium distribution ring (19), a wedge-shaped sealing ring (20), packing (21) and a third O-shaped sealing ring (23);

the dust ring (12) is provided with 2 channels, the arch seal (14) is provided with 4 channels, the dust ring (12) is arranged in a groove at the front end of the arch combined seal cavity (7) in parallel, the arch seals (14) are symmetrically arranged back to back and are respectively arranged at two sides of the second distribution ring (15); the arch seals (14) are sequentially arranged in the arch combined seal cavity (7), the arch seals (14) are assembled into a whole through the arch seal gland (4), and 2V-shaped grooves are formed in the inner wall of each arch seal (14);

the special-shaped distribution ring is characterized in that a second O-shaped sealing ring (10) is arranged on the end face of the special-shaped distribution ring (9) and the annular contact surface of the arch-shaped combined sealing cavity (7), the second O-shaped sealing ring (10) is arranged on the annular contact surface of the outer ring of the special-shaped distribution ring (9) and the arch-shaped combined sealing cavity fixing seat (8), and the solid particles are blocked and sealed under the combined action of nitrogen back blowing introduced through a third sealing medium injection hose (16) and shaft sleeve spiral back pushing between the inner ring of the special-shaped distribution ring (9) and a rotating shaft.

2. A two-stage composite rotary shaft seal assembly as claimed in claim 1, wherein: the stuffing box (2) is provided with a nitrogen isolation bin which is communicated with the first sealing medium injection hose (3), and nitrogen is injected into the nitrogen isolation bin through the first sealing medium injection hose (3).

3. A two-stage composite rotary shaft seal assembly as claimed in claim 1, wherein: the arch-shaped combined sealing cavity fixing seat (8) is connected with an end plate of the rotating shaft equipment into a whole through welding or threaded connection, and the verticality between the sealing end face of the arch-shaped combined sealing cavity fixing seat (8) and the center of the rotating shaft equipment is not larger than 0.15 mm.

4. A two-stage composite rotary shaft seal assembly as claimed in claim 1, wherein: the sealing medium injection hose (6) is divided into 3 paths to enter the arch-shaped combined sealing cavity (7), the first path enters the 2 dust rings (12) through a first distribution ring (13) arranged at the front end of the arch-shaped combined sealing cavity (7), the second path and the third path enter a second distribution ring (15) through oil injection holes arranged at the middle part and the rear end of the arch-shaped combined sealing cavity (7) to be distributed, the distributed paths enter the middle 2 arch-shaped seals (14) and the rear 2 arch-shaped seals (14) respectively, 2V-shaped grooves are arranged on the inner wall of each arch-shaped seal (14), and the grooves are mainly used as a flow passage and a storage space for lubricating grease in the working state of the arch-shaped seals (14), so that the lubricating grease can lubricate the working surface of the arch-shaped seals timely and effectively.

5. A two-stage composite rotary shaft seal assembly as claimed in claim 1, wherein: the sealing gas pressure of the secondary packing sealing bin is higher than the highest working pressure in the rotating shaft equipment shell.

6. A two-stage composite rotary shaft seal assembly as claimed in claim 1, wherein: and the stuffing box (2) and the arch-shaped combined sealing cavity fixing seat (8) are fastened by a stuffing box fixing bolt and then are subjected to finish machining, and meanwhile, the concentricity installation of the inner wall of the stuffing box (2) and the center of the rotating shaft equipment is ensured.

7. A two-stage composite rotary shaft seal assembly as claimed in claim 1, wherein: the surface of the shaft sleeve (22) is sprayed with a hard coating and is polished.