CN212297587U

CN212297587U - Rotating shaft dynamic sealing structure

Info

Publication number: CN212297587U
Application number: CN202021402184.1U
Authority: CN
Inventors: 陈博; 刘凯; 史建兵
Original assignee: Shaanxi Hongda Industrial Co ltd
Current assignee: Shaanxi Hongda Industrial Co ltd
Priority date: 2020-07-16
Filing date: 2020-07-16
Publication date: 2021-01-05
Anticipated expiration: 2030-07-16

Abstract

The utility model discloses a dynamic seal structure of a rotating shaft, which comprises a shell and a rotating shaft; the shaft hole is formed in the shell, the rotating shaft penetrates out of the shaft hole, the rotating shaft on the outer side of the shell is sleeved with the packing box, the packing box comprises a bottom plate and a cylinder connected to one side of the bottom plate, a first round hole is formed in the middle of the bottom plate, the diameter of the first round hole is larger than that of the rotating shaft, a plurality of first fixing holes are formed in the edge of the bottom plate, and the packing box is connected to the shell through bolts; the cylinder is sequentially provided with an air blowing ring, at least two sealing rings and a gland bush of the stuffing box from inside to outside; the side wall of the air blowing ring is provided with an air blowing hole, the air blowing hole is connected with compressed air, and the inner diameter of the air blowing ring is larger than the diameter of the rotating shaft. According to the technical scheme, the particle powder is reduced or prevented from entering the sealing ring, and the service life of the sealing ring is prolonged; the structure of the semi-stuffing box and the semi-sealing ring simplifies the step of replacing the sealing ring, and saves the maintenance workload and the maintenance time.

Description

Rotating shaft dynamic sealing structure

Technical Field

The utility model relates to a mechanical seal field, concretely relates to pivot dynamic seal structure.

Background

Dynamic seals are seals between relatively moving parts in a machine installation. The seal ring is often used as a member for solving the problem of dynamic sealing between the rotating shaft and the housing. The sealing effect is achieved mainly by means of elastic force action generated by the elastic sealing ring, and the medium is prevented from leaking from the high-pressure end to the low-pressure end.

In the solid powder stirring device, particle powder easily enters the sealing ring, so that lubricating grease is dried, friction is increased, sealing is easy to lose efficacy, and the sealing ring is frequently required to be replaced. Therefore, particle powder is reduced or prevented from entering the sealing ring, the service life of the sealing ring in the powder stirring device can be prolonged, and the maintenance frequency is reduced.

Disclosure of Invention

For solving above technical problem, the utility model aims at providing a pivot moves seal structure can avoid the material in the casing to get into the sealing washer, prolongs the life of sealing washer, reduces the maintenance number of times.

In order to achieve the above purpose, the present invention adopts the following technical solution.

A dynamic seal structure of a rotating shaft comprises a shell and the rotating shaft; the packing box comprises a bottom plate and a cylinder connected to one side of the bottom plate, wherein a first round hole is formed in the middle of the bottom plate, the diameter of the first round hole is larger than that of the rotating shaft, a plurality of first fixing holes are formed in the edge of the bottom plate, and the packing box is connected to the shell through bolts; the stuffing box is sequentially provided with an air blowing ring, at least two sealing rings and a stuffing box gland from inside to outside; the side wall of the air blowing ring is provided with an air blowing hole, the air blowing hole is connected with compressed air, and the inner diameter of the air blowing ring is larger than the diameter of the rotating shaft.

Furthermore, the stuffing box comprises two half stuffing boxes which are symmetrical about the central axis of the stuffing box, each half stuffing box is provided with a connecting hole, and the two half stuffing boxes are connected through a bolt group; the sealing ring comprises a pair of semi-sealing rings which are symmetrical about the middle axial plane, and at least two pairs of semi-sealing rings are sleeved on the rotating shaft in a mutually staggered mode.

Furthermore, three pairs of half sealing rings are sleeved on the rotating shaft.

Furthermore, the sealing ring is made of polytetrafluoroethylene.

Furthermore, the number of the air blowing holes is six, the six air blowing holes are radially and uniformly distributed on the air blowing ring, and an air inlet hole is formed in the side wall of the cylinder of the stuffing box.

Furthermore, a second round hole is formed in the gland of the packing box, a screw hole is formed in the packing box, and the gland of the packing box is connected to the packing box through a bolt.

Compared with the dynamic sealing structure in the prior art, the technical scheme of the utility model reduces or avoids the particle powder entering the sealing ring, and prolongs the service life of the sealing ring; the stuffing box structure formed by two half stuffing box structures greatly simplifies the step of replacing the sealing ring, and saves the maintenance workload and the maintenance time.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

Fig. 1 is a partial schematic view of the assembly of the housing, the rotating shaft and the speed reducer in one embodiment of the rotating shaft dynamic seal structure of the present invention;

FIG. 2 is an enlarged view of a portion of FIG. 1 at A;

FIG. 3 is a cross-sectional view C-C of a front view of the blow ring;

FIG. 4 is a sectional view taken along line B-B of a top view of the blow ring;

FIG. 5 is a cross-sectional view of a front view of the stuffing box;

FIG. 6 is a top view of a stuffing box;

FIG. 7 is a top view of the stuffing box cut along the medial axis plane into two half stuffing boxes;

FIG. 8 is a cross-sectional view of a front view of the seal ring;

FIG. 9 is a top view of the seal ring;

fig. 10 is a top view of the seal ring cut along the medial axis plane into two half seal rings.

In the above figures: 1, a shell; 2, rotating a shaft; 3, a stuffing box; 301 a base plate; 302 a cylinder; 303 a first circular aperture; 304 half stuffing boxes; 305 a connecting hole; 306 a first fixing hole; 307 air intake holes; 4, blowing a ring; 401 air blowing holes; 5, sealing rings; 501, half sealing ring; 6, a gland bush of the stuffing box; and 7, a speed reducer.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments accompanied with figures are described in detail below.

In the following description, specific details are set forth in order to provide a thorough understanding of the present invention. The invention can be implemented in a number of other ways than those described herein, and those skilled in the art will be able to make similar generalizations without departing from the spirit of the invention. The invention is therefore not limited to the specific embodiments disclosed below.

Referring to fig. 1, 2, 3 and 4, a dynamic seal structure for a rotating shaft includes a housing 1 and a rotating shaft 2; the packing box comprises a shell 1, a shaft hole is formed in the shell 1, a rotating shaft 2 penetrates out of the shaft hole, a packing box 3 is sleeved on the rotating shaft 2 on the outer side of the shell 1, the packing box 3 comprises a bottom plate 301 and a cylinder 302 connected to one side of the bottom plate 301, a first round hole 303 is formed in the middle of the bottom plate 301, the diameter of the first round hole 303 is larger than that of the rotating shaft 2, a plurality of first fixing holes 306 are formed in the edge of the bottom plate 301, and the packing box 3 is connected to the shell 1 through bolts; the stuffing box 3 is sequentially provided with an air blowing ring 4, at least two sealing rings 5 and a stuffing box gland 6 from inside to outside; the side wall of the air blowing ring 4 is provided with an air blowing hole 401, the air blowing hole 401 is connected with compressed air, and the inner diameter of the air blowing ring 4 is larger than the diameter of the rotating shaft 2.

In the above embodiment, the rotating shaft 2 penetrates out of the casing 1 and then is connected with the stuffing box 3, the air blowing ring 4 and the sealing ring 5 are sequentially sleeved on the rotating shaft 2 from inside to outside in the stuffing box 3, because the diameter of the first round hole 303 on the bottom plate 301 of the stuffing box 3 is larger than the diameter of the rotating shaft 2, the inner diameter of the air blowing ring 4 is larger than the diameter of the rotating shaft 2, and the sealing ring 5 is in interference fit with the rotating shaft 2, therefore, after the air blowing ring 4 is connected with high-pressure gas, air can only flow to one side in the casing 1, and the outward leakage of materials in the casing 1 through the sealing ring 5 is avoided. The rotating shaft dynamic seal structure is often applied to a stirring device, and is particularly suitable for a stirring device in which the stirred material in the shell 1 is dry powder, and the powder is continuously blown to the inside of the shell 1 by continuous high-pressure gas.

Further, referring to fig. 5, 6 and 7, the stuffing box 3 comprises two half stuffing boxes 304 symmetrical about the central axis thereof, each half stuffing box 304 is provided with a connecting hole 305, and the two half stuffing boxes 304 are connected by a bolt set; referring to fig. 8, 9 and 10, the seal ring 5 includes a pair of half seal rings 501 symmetrical about a central axis thereof, and at least two pairs of half seal rings 501 are disposed on the rotating shaft 2 in a staggered manner.

In the stirring device, the speed reducer is usually connected outside the casing 1, the sealing failure is often due to the abrasion of the sealing ring 5, the speed reducer 7 and the casing 1 are usually removed when the sealing ring 5 is replaced, the labor intensity is very large, and in order to avoid excessive disassembly, in the above embodiment, the stuffing box 3 is divided into two half stuffing boxes 304 along the central axis, the two half stuffing boxes 304 are provided with connecting holes 305 connected by bolt sets, and the sealing ring 5 is divided into two half sealing rings 501 along the central axis. When replacing, the two half stuffing boxes 304 are detached, the old half seal ring 501 is removed, a new half seal ring 501 is replaced, the two half stuffing boxes 304 are connected into a whole, and then the two half stuffing boxes are connected to the shell 1. Since a gap exists between the two half seal rings 501, which may cause leakage, more than two pairs of half seal rings 501 are usually used for sealing, and the joints of the two half seal rings 501 are offset from each other. By adopting the method, the speed reducer does not need to be disassembled, the workload is greatly reduced, the time and the labor are saved, and the efficiency of replacing the sealing ring is improved.

Further, referring to fig. 2, three half-and-half sealing rings 501 are sleeved on the rotating shaft 2. In the above embodiments, reliable sealing can be achieved by specifically using three half-and-half sealing rings 501.

Furthermore, the sealing ring 5 is made of polytetrafluoroethylene. The polytetrafluoroethylene sealing ring 5 has good characteristics of water resistance, high temperature resistance, corrosion resistance and ageing resistance.

Further, referring to fig. 3 and 4, the number of the blowing holes 401 is six, the six blowing holes 401 are radially and uniformly distributed on the blowing ring 4, and the side wall of the cylinder 302 of the stuffing box 3 is provided with an air inlet hole 307.

In the above embodiment, in order to make the gas uniform, the gas blowing holes 401 are uniformly arranged on the gas blowing ring 4. Correspondingly, the cylinder 302 of the stuffing box 3 is provided with at least one air inlet hole 307 aligned with the air blowing hole 401.

Furthermore, a second round hole is formed in the gland 6 of the packing box, a screw hole is formed in the packing box 3, and the gland 6 of the packing box is connected to the packing box 3 through a bolt.

In the above embodiment, specifically, the gland 6 of the stuffing box is provided with a second round hole, the stuffing box 3 is provided with a screw hole, and the gland 6 of the stuffing box is connected to the bottom plate 301 through a bolt.

Exemplary, the following is a method of replacing a seal ring for a dynamic seal of a rotating shaft, wherein the stuffing box consists of two half stuffing boxes, each seal ring consists of a pair of half seal rings:

the method comprises the following steps that firstly, bolts for connecting two half stuffing boxes are dismounted, and the two half stuffing boxes are opened;

step two, all the old semi-seal rings are taken out, the new semi-seal rings with the same number of pairs are replaced, and the joints of the plurality of semi-seal rings are staggered;

and step three, fastening the two half stuffing boxes by using bolts.

Furthermore, in the second step, the number of pairs of the half seal rings is three, and the included angles of the joint surfaces of the three pairs of new half seal rings are 120 degrees.

Although the invention has been described in detail in this specification with reference to specific embodiments and illustrative embodiments, it will be apparent to those skilled in the art that certain changes and modifications can be made therein without departing from the scope of the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims

1. A rotating shaft dynamic seal structure is characterized by comprising a shell (1) and a rotating shaft (2); the packing box is characterized in that a shaft hole is formed in the shell (1), the rotating shaft (2) penetrates out of the shaft hole, a packing box (3) is sleeved on the rotating shaft (2) on the outer side of the shell (1), the packing box (3) comprises a bottom plate (301) and a cylinder (302) connected to one side of the bottom plate (301), a first round hole (303) is formed in the middle of the bottom plate (301), the diameter of the first round hole (303) is larger than that of the rotating shaft (2), a plurality of first fixing holes (306) are formed in the edge of the bottom plate (301), and the packing box (3) is connected to the shell (1) through bolts; the packing box (3) is sequentially provided with an air blowing ring (4), at least two sealing rings (5) and a packing box gland (6) from inside to outside; the side wall of the air blowing ring (4) is provided with an air blowing hole (401), the air blowing hole (401) is connected with compressed air, and the inner diameter of the air blowing ring (4) is larger than the diameter of the rotating shaft (2).

2. The rotary shaft dynamic seal structure according to claim 1, characterized in that the stuffing box (3) comprises two half stuffing boxes (304) which are symmetrical about the central axial plane thereof, each half stuffing box (304) is provided with a connecting hole (305), and the two half stuffing boxes (304) are connected through a bolt group; the sealing ring (5) comprises a pair of semi-sealing rings (501) which are symmetrical about the central axial plane, and at least two pairs of semi-sealing rings (501) are sleeved on the rotating shaft (2) in a mutually staggered mode.

3. The rotating shaft dynamic seal structure according to claim 2, characterized in that three pairs of half seal rings (501) are sleeved on the rotating shaft (2).

4. The rotating shaft dynamic seal structure according to claim 1, characterized in that the material of the seal ring (5) is polytetrafluoroethylene.

5. The rotating shaft dynamic seal structure is characterized in that the number of the air blowing holes (401) is six, the six air blowing holes (401) are radially and uniformly distributed on the air blowing ring (4), and the side wall of the cylinder (302) of the stuffing box (3) is provided with an air inlet hole (307).

6. A rotary shaft dynamic seal structure according to claim 1, characterized in that the gland (6) of the stuffing box is provided with a second round hole, the stuffing box (3) is provided with a screw hole, and the gland (6) of the stuffing box is connected to the stuffing box (3) through a bolt.