Sealing structure suitable for impurity medium

Abstract

The utility model belongs to the technical field of sealing, and particularly relates to a sealing structure suitable for impurity media, which comprises a movable ring seat, a movable ring anti-rotating pin, a movable ring, a static ring, a static ring seat, a spring and a static ring anti-rotating pin, and mainly aims at the sealing requirements that the axial installation space is compact, the atmospheric side needs bidirectional balance capability and can be integrated and interchanged. The sealing static ring assembly is of a two-way balance structure. And the static ring anti-rotating pin is axially arranged on the static ring seat and is adjusted by the spring to float along with the static ring. And the O-shaped ring of the movable and static rings is matched with the ring seat with the groove for limiting, so that the O-shaped ring is prevented from falling off the ring seat. And the static ring floats and is suitable for high-pressure and high-speed occasions. The static ring compensation spring does not make contact with media, and the structure can meet the use requirement of the media containing impurities for mechanical sealing.

Description

Technical Field

[0001] The utility model belongs to the technical field of sealing, and particularly relates to a sealing structure suitable for impurity media. Background Art

[0002] For a medium containing impurities and under a negative pressure working condition, in the sealing design, in addition to paying attention to spring protection, the problem of the static ring limit also needs to be considered. When selecting a standard type of seal, it is best to select a reverse balance type structure for the dynamic ring. Conventional seals are all designed to work under a pressurized working condition and cannot meet the usage requirements. How to design a seal that is both suitable for an impurity-containing working condition and has the ability to withstand reverse pressure is the key to solving the stable application of the seal in such working conditions. Content of the Utility Model

[0003] To solve the above technical problems, the utility model provides a sealing structure suitable for impurity media, including: a dynamic ring seat O-ring, an internal hexagonal socket set screw, a dynamic ring seat, a dynamic ring anti-rotation pin, a dynamic ring O-ring, a dynamic ring, a static ring, a static ring O-ring, a static ring seat, a static ring seat O-ring, a spring, and a static ring anti-rotation pin; wherein,

[0004] The dynamic ring is integrally in the shape of a horse's head, with a circumferential protrusion on the outer periphery as a sealing surface; a anti-rotation groove is provided at the tail, and it is floatingly sealed with the dynamic ring seat through the dynamic ring O-ring. A dynamic ring anti-rotation pin is arranged in the anti-rotation groove, and the other end of the dynamic ring anti-rotation pin is installed in the dynamic ring seat, and the dynamic ring rotates synchronously with the dynamic ring seat;

[0005] The dynamic ring seat is installed on the outside of the shaft sleeve, and two steps are provided in the inner hole. The circumferential surface of the step at the upper end is matched with the dynamic ring for sealing; a plurality of uniformly arranged counterbores are provided on the end surface of the lower step, and the dynamic ring anti-rotation pins are press-fitted in the counterbores; the dynamic ring seat is provided with a threaded hole, which is matched with the internal hexagonal socket set screw to fasten the dynamic ring seat on the shaft sleeve;

[0006] The static ring is mutually matched with the dynamic ring for sealing, and is in the shape of a horse's head, with a circumferential protrusion at the head end as a sealing surface, and an anti-rotation groove is provided on the end surface of the tail. A static ring anti-rotation pin is assembled in the anti-rotation groove, and the other end of the static ring anti-rotation pin is assembled in the static ring seat, and the static ring is kept stationary with the static ring seat by overcoming the rotation torque through the static ring anti-rotation pin; the static ring is floatingly sealed with the static ring seat through the static ring O-ring.

[0007] The static ring seat is provided with four shoulders from the outside to the inside on the outer circle, namely an outer shoulder, a transition shoulder, a sealing shoulder and an inner shoulder, wherein,

[0008] The outer shoulder is the same as the outer circle of the dynamic ring seat, and the transition shoulder has a clearance fit with the gland; the inner shoulder has a small clearance fit with the gland. Between the transition shoulder and the inner shoulder is the sealing shoulder for the floating static ring O-ring between the static ring seat and the gland. The transition end faces of the inner shoulder and the sealing shoulder are in contact with the gland, and the axial dimension of the sealing shoulder is designed according to the expansion space of the static ring O-ring; there is a step in the inner hole of the static ring seat, and a groove is provided on the step that cooperates with the static ring O-ring to prevent the static ring O-ring from coming out; there is a spring counterbore axially arranged on the static ring seat, and the anti-rotation pin holes are arranged staggeredly according to the spring hole spacing;

[0009] The anti-rotation pin of the static ring is floatingly installed in the anti-rotation pin hole of the static ring seat, with one end abutting against the static ring and the other end abutting against the counterbore spring of the static ring seat; one end of the spring is installed in the counterbore of the static ring seat, and the other end abuts against the end face of the static ring. The spring provides elastic compensation for the static ring;

[0010] The dynamic ring friction pair rotates in cooperation with the static ring friction pair; the static ring seat is installed in the gland.

[0011] Further, the circumference of the step at the upper end of the dynamic ring seat cooperates with the dynamic ring, and a groove is provided on the circumference that cooperates with the dynamic ring O-ring to limit the dynamic ring O-ring and prevent the O-ring from coming out.

[0012] Further, a groove is provided in the inner hole of the dynamic ring seat for installing the dynamic ring seat O-ring, and the O-ring plays a sealing role between the dynamic ring seat and the shaft sleeve.

[0013] Further, an anti-rotation groove is provided on the inner shoulder of the static ring seat to cooperate with the anti-rotation pin of the gland for anti-rotation.

[0014] Further, the sealing end face of the static ring is wider than the sealing end face of the dynamic ring.

[0015] Further, a chamfer is provided at the transition between the outer shoulder and the transition shoulder to prevent interference with the position of the mating component.

[0016] The advantages of the present invention are as follows:

[0017] This solution has good sealing effect and long service life. The static ring compensation spring adopted does not contact the medium, and this structure can meet the use requirements of mechanical seals for media containing impurities. Using the radial space integration design of the static ring seat, it has good standard interchangeability. Description of the Drawings

[0018] Figure 1 is the structural schematic diagram of the present utility model;

[0019] Figure 2 is the structural schematic diagram of the dynamic ring seat;

[0020] Figure 3 is the structural schematic diagram of the static ring seat;

[0021] Figure 4It is a schematic structural diagram of the moving ring;

[0022] Figure 5 It is a schematic structural diagram of the stationary ring;

[0023] Explanation of the part numbers in the figure: 1 - O-ring of the moving ring seat; 2 - Socket head cap screw; 3 - Moving ring seat; 4 - Anti-rotation pin of the moving ring; 5 - O-ring of the moving ring; 6 - Moving ring; 7 - Stationary ring; 8 - O-ring of the stationary ring; 9 - Stationary ring seat; 10 - O-ring of the stationary ring seat; 11 - Spring; 12 - Anti-rotation pin of the stationary ring. Specific embodiments

[0024] The principles and features of the present utility model will be described below in conjunction with the accompanying drawings. The examples given are only used to explain the present utility model and are not intended to limit the scope of the present utility model.

[0025] The present utility model belongs to the category of mechanical seals and is a mechanically sealed structure with a compact structure, mainly aiming at the sealing requirements of compact axial installation space, the need for two-way balance on the atmosphere side, and the ability to be integrated and interchanged. The stationary ring assembly of this seal is a two-way balance structure. The anti-rotation pin 12 of the stationary ring is axially arranged on the stationary ring seat 9 and floats with the stationary ring through the adjustment of the spring 11. The O-rings of the moving and stationary rings are matched with the ring seats provided with grooves for position limitation to ensure that the O-rings do not fall off the ring seats. The floating of the stationary ring is suitable for occasions with higher pressure and higher speed. The compensation spring of the stationary ring does not contact the medium, and this structure can meet the use requirements of mechanical seals for media containing impurities.

[0026] As Figure 1 shown, the present utility model provides a sealing structure suitable for impurity media. This sealing structure is suitable for the flushing scheme of Plan11 and has a mechanical seal structure with spring protection, floating compensation of the stationary ring, and reverse balance type, specifically including: O-ring 1 of the moving ring seat, socket head cap screw 2, moving ring seat 3, anti-rotation pin 4 of the moving ring, O-ring 5 of the moving ring, moving ring 6, stationary ring 7, O-ring 8 of the stationary ring, stationary ring seat 9, O-ring 10 of the stationary ring seat, spring 11 and anti-rotation pin 12 of the stationary ring. Among them,

[0027] The moving ring 6 is of an integral structure, designed in the shape of a horse's head, with an anti-rotation groove provided at the tail, floatingly sealed with the moving ring seat 3 through the O-ring 5 of the moving ring, and running synchronously with the moving ring seat 3 through the anti-rotation pin 4 of the moving ring.

[0028] The moving ring seat 3 has a groove in the inner hole that mates with the shaft sleeve for installing the O-ring 1 of the moving ring seat. The O-ring 1 of the moving ring seat serves as a seal between the moving ring seat 3 and the shaft sleeve. The inner hole of the moving ring seat 3 has a step, and the circumference of the step mates with the moving ring 6. The circumference that mates with the O-ring 1 of the moving ring has a groove for limiting the O-ring 1 of the moving ring and preventing the O-ring from coming out. Another stepped end face of the moving ring seat 3 has a counterbore that is press-fitted with the anti-rotation pin 4 of the moving ring. The anti-rotation pins 4 of the moving ring are evenly arranged. The moving ring seat 3 has threaded holes that mate with the socket head cap screws 2 with recessed ends to fasten the moving ring seat 3 to the shaft sleeve.

[0029] The stationary ring 7 is an integral structure designed in the shape of a horse's head, with an anti-rotation groove at the tail. It is floatingly sealed with the stationary ring seat 9 through the O-ring 8 of the stationary ring and remains stationary with the stationary ring seat 9 by overcoming the rotational torque through the anti-rotation pin 12 of the stationary ring.

[0030] The stationary ring seat 9 has four shoulders on its outer circle, namely the outer shoulder 901, the transition shoulder 902, the sealing shoulder 903, and the inner shoulder 904.

[0031] The outer shoulder 901 is the same as the outer circle of the moving ring seat 3, and there is a chamfer at the transition of the shoulders. The transition shoulder 902 has a clearance fit with the gland, and the inner shoulder 904 has a small clearance fit with the gland. Between the transition shoulder 902 and the inner shoulder 904 is the sealing shoulder 903 for the O-ring 10 of the stationary ring seat that is floatingly installed between the stationary ring seat 9 and the gland. The transition end face between the inner shoulder 904 and the sealing shoulder 903 fits with the gland, and the axial dimension of the sealing shoulder is designed based on the expansion space of the O-ring 10 of the stationary ring seat.

[0032] The inner shoulder 904 has an anti-rotation groove that mates with the anti-rotation pin of the gland to prevent rotation. The inner hole of the stationary ring seat 9 has a step, and the step that mates with the O-ring 8 of the stationary ring has a groove for preventing the O-ring from coming out. The stationary ring seat 9 has a counterbore for the spring 11 axially, and the anti-rotation pin holes are symmetrically arranged according to the hole pitch of the spring 11.

[0033] The anti-rotation pin 12 of the stationary ring is floatingly installed in the anti-rotation pin hole of the stationary ring seat, with one end abutting against the stationary ring 7 and the other end abutting against a spring (a special spring for the anti-rotation pin 12 of the stationary ring, this spring is in the counterbore of the stationary ring seat 9, with one end abutting against the anti-rotation pin and the other end abutting against the stationary ring seat 9).

[0034] One end of the spring 11 is installed in the counterbore of the stationary ring seat 9, and the other end abuts against the end face of the stationary ring 7. The spring 11 provides elastic compensation for the stationary ring 7. The moving ring friction pair rotates in cooperation with the stationary ring friction pair. The stationary ring seat 9 is installed in the gland and is assisted by an O-ring for sealing.

[0035] During operation, the moving ring rotates with the moving ring seat 3, and the stationary ring is installed on the gland by the stationary ring seat 9. The gland is fixed to the pump body. The friction pair realizes dynamic sealing, and the auxiliary O-ring realizes static sealing to ensure that the medium does not leak.

[0036] The installation sequence of this utility model is as follows: clean the pump shaft, install the cartridge seal in the seal cavity, tighten the set screw, remove the positioning block, connect the flushing pipeline, evacuate the gas in the pipeline, and after checking by turning the shaft by hand, the equipment can be operated.

[0037] In this solution, the stationary ring 7 is designed as a horse-head-shaped balanced structure. The mating surface of the stationary ring seat 9 and the stationary ring O-ring 8 is provided with a groove, and the limiting O-ring prevents it from coming off. The shoulder of the stationary ring seat 9 is used for positioning and mating assembly. The anti-rotation pin 12 of the stationary ring floats with the stationary ring 7 and prevents rotation. The spring 11 that provides floating compensation for the anti-rotation pin 12 of the stationary ring also indirectly provides compensation for the stationary ring 7. The moving ring is designed as a horse-head-shaped structure. The mating surface of the moving ring seat 3 and the moving ring O-ring 5 is provided with a groove, and the limiting O-ring prevents it from coming off. The dimension of the mating surface of the stationary ring seat 9 and the O-ring is designed to have reverse balance ability. When the medium is in a negative pressure working condition, the stationary ring does not need to be designed with a limiting device. This sealing structure is suitable for negative pressure working conditions containing impurities that require spring protection. The outer circle of the seal contacts the medium, which is called the medium side, and the side that does not contact the medium is called the outer side or the atmosphere side. The stationary ring and the stationary ring seat of this seal are used as a component and are installed on the gland during use. During normal operation, it must be ensured that the stationary ring seat does not produce axial displacement due to pressure fluctuations. In actual design, through dimension control, when the pressure on the medium side is high, the stationary ring seat leans towards the gland under the action of the medium pressure and the spring force. When the medium pressure is lower than the atmospheric pressure, just looking at the axial thrust generated by the mating of the stationary ring seat and the gland, there is a tendency for the stationary ring seat and the gland to separate, which may cause the O-ring mating the stationary ring seat and the gland to come off the gland, resulting in seal leakage. At this time, the dimension at the mating O-ring of the stationary ring seat and the stationary ring must be considered, so that the force that makes the stationary ring seat lean towards the gland generated here is equal to or greater than the force that makes it separate, ensuring that the position of the stationary ring seat remains unchanged, that is, the reverse balance ability.

[0038] The sealing end face of the stationary ring is wider than that of the moving ring. The sealing structure of this solution is generally used for media such as easy crystallization and scaling. The contact surfaces of the two friction pairs are generally designed to be of equal width or one is slightly wider. The purpose of being a little wider is to compensate for the shaft runout of the pump. If the designed sealing surface is too wide, the crystallized substances of the leaked medium will accumulate on the wider friction pair, and over time, it will cause a large amount of seal leakage.

[0039] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A sealing structure applicable to impurity media, characterized in that, Comprising: Moving ring seat, anti-rotation pin for moving ring, moving ring, static ring, static ring seat, spring and anti-rotation pin for static ring, wherein, The moving ring is integrally in the shape of a horse's head, with a circumferential protrusion on the outer periphery as the sealing surface; an anti-rotation groove is provided at the tail, and it is floatingly sealed with the moving ring seat through a moving ring O-ring. An anti-rotation pin for the moving ring is arranged in the anti-rotation groove, and the other end of the anti-rotation pin for the moving ring is installed in the moving ring seat, and the moving ring and the moving ring seat rotate synchronously; The moving ring seat is installed on the outside of the shaft sleeve, and two steps are provided in the inner hole. The circumference of the step at the upper end is matched with the moving ring for sealing; multiple evenly arranged counterbores are provided on the end face of the lower step, and the anti-rotation pin for the moving ring is press-fitted in the counterbores. The moving ring seat is provided with a threaded hole, which is matched with an internal hexagon socket set screw to fasten the moving ring seat on the shaft sleeve; The static ring is matched with the moving ring for sealing, in the shape of a horse's head, with a circumferential protrusion at the head end as the sealing surface, and an anti-rotation groove is provided on the end face of the tail. An anti-rotation pin for the static ring is assembled in the anti-rotation groove, and the other end of the anti-rotation pin for the static ring is assembled in the static ring seat; the static ring is floatingly sealed with the static ring seat through a static ring O-ring; The static ring seat has four shoulders from the outside to the inside of the outer circle, namely the outer shoulder, the transition shoulder, the sealing shoulder and the inner shoulder. Among them, the outer shoulder is the same as the outer circle of the moving ring seat, and the transition shoulder has a clearance fit with the gland; the inner shoulder has a small clearance fit with the gland. Between the transition shoulder and the inner shoulder is the sealing shoulder where the static ring seat and the gland float the static ring O-ring, and the transition end face between the inner shoulder and the sealing shoulder fits with the gland; a step is provided in the inner hole of the static ring seat, and a groove is provided on the step that cooperates with the static ring O-ring; a spring counterbore is axially provided in the static ring seat; the anti-rotation pin for the static ring floats in the anti-rotation pin hole of the static ring seat, one end abuts against the static ring, and one end abuts against the counterbore spring of the static ring seat; one end of the spring is installed in the counterbore of the static ring seat, and the other end abuts against the end face of the static ring, and the spring provides elastic compensation for the static ring; the moving ring friction pair rotates in cooperation with the static ring friction pair; the static ring seat is installed in the gland.

2. The sealing structure applicable to impurity medium as described in claim 1, wherein The circumference of the step at the upper end of the moving ring seat is matched with the moving ring, and a groove is provided on the circumference that cooperates with the moving ring O-ring.

3. A sealing structure applicable to impurity media as described in claim 1, characterized in that, A groove is provided in the inner hole of the moving ring seat.

4. A sealing structure applicable to impurity media as described in claim 1, characterized in that, An anti-rotation groove is provided on the inner shoulder of the static ring seat, which cooperates with the anti-rotation pin of the gland to prevent rotation.

5. A sealing structure applicable to impurity media as described in claim 1, characterized in that, The sealing end face of the static ring is wider than the sealing end face of the moving ring.

6. The sealing structure applicable to impurity medium as described in claim 1, characterized in that, A chamfer is provided at the transition between the outer shoulder and the transition shoulder.

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