Surrounding strip, overhaul sealing structure and main shaft sealing device

Abstract

The invention relates to the technical field of overhaul sealing, in particular to a shroud ring, an overhaul sealing structure and a main shaft sealing device.The shroud ring comprises a shroud ring body which is an annular rubber ring; an annular cavity is formed in the shroud ring body. According to the shroud ring, the overhaul sealing structure and the main shaft sealing device, deformation of the exterior of the shroud ring body can be increased, the shroud ring body can expand, and therefore the sealing contact area is increased, and the sealing effect is improved.

Description

Technical Field

[0001] The invention relates to the technical field of maintenance seals, and in particular to a shroud, a maintenance seal structure and a main shaft sealing device. Background Art

[0002] The main shaft sealing device mainly includes two parts: working seal and maintenance seal. The maintenance seal is a bearing seal required when the turbine is shut down or overhauling the working seal and water guide bearing. It prevents backflow into the machine pit when the water level is high.

[0003] The traditional maintenance sealing air belt adopts a rubber belt. During installation, the two ends of the belt are glued tightly with special glue and installed in the maintenance sealing groove. The cavity space of the sealing groove is slightly larger than the size of the belt. After the compressed air is introduced from the side vent, the belt is squeezed to hug the main shaft body to achieve the desired effect. The existing belt has poor pasting effect at both ends. After the air is introduced, there is leakage at the joint surface, the pressure cannot be maintained, and the belt hugs the main shaft body after ventilation. After the ventilation is stopped, the belt does not retract to its original position, which causes the belt to be damaged and fail due to friction after the unit is started. To this end, the present invention provides a belt, a maintenance sealing structure and a main shaft sealing device. Summary of the invention

[0004] In view of the problems existing in the above-mentioned existing shrouds, maintenance seal structures and main shaft sealing devices, the present invention is proposed.

[0005] Therefore, one of the objects of the present invention is to provide a shroud which aims to improve the sealing effect.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a belt, comprising a belt body, which is a rubber ring arranged in an annular shape; an annular cavity is arranged inside the belt body.

[0007] As a preferred solution of the belt of the present invention, the belt body is provided with an air inlet communicating with the cavity.

[0008] The beneficial effect of this belt is that it can increase the deformation of the outer part of the belt body, so that it can expand, thereby increasing the sealing contact area and increasing the sealing effect.

[0009] Another object of the present invention is to provide a maintenance seal structure, the purpose of which is to improve the sealing effect.

[0010] In order to solve the above technical problems, the present invention provides the following technical solutions: an inspection and sealing structure including a shroud, further comprising;

[0011] A mounting seat, which is arranged in an annular shape, a receiving groove with a notch arranged on the inner side of the mounting seat, and an air channel arranged on the mounting seat;

[0012] The shroud body is located in the accommodating groove, and the airway end is connected to the air inlet.

[0013] As a preferred solution of the maintenance sealing structure of the present invention, the mounting seat includes a base and a pressure plate, and grooves are provided on the mounting seat and the base, and the grooves are spliced ​​into the accommodating groove.

[0014] As a preferred solution of the maintenance sealing structure of the present invention, the air duct is located in the mounting seat, and an air inlet nozzle is provided at one end of the air duct.

[0015] As a preferred solution of the maintenance sealing structure of the present invention, the width of the connection portion between the accommodating groove and the airway is greater than the width of the notch.

[0016] The beneficial effects of this maintenance sealing structure are: the expansion protrusion position of the belt body can be limited by the accommodating groove, the sealing contact part of the belt body can be limited, and the belt body can be smoothly retracted after shrinking, avoiding friction damage caused by continuous contact.

[0017] The last object of the present invention is to provide a main shaft sealing device, the purpose of which is to increase the sealing performance of the main shaft body during maintenance.

[0018] In order to solve the above technical problems, the present invention provides the following technical solutions: A main shaft sealing device including a maintenance sealing structure: further comprising a main shaft body, and a sealing body arranged outside the main shaft body;

[0019] The mounting seat is arranged on the outer side of the main shaft and connected to the sealing body.

[0020] As a preferred solution of the main shaft sealing device of the present invention, a drain port is provided on the sealing body.

[0021] As a preferred solution of the main shaft sealing device of the present invention, the gap between the sealing body and the main shaft body is 0.3-0.4 mm, and a labyrinth seal is adopted.

[0022] As a preferred solution of the main shaft sealing device of the present invention, the gap between the accommodating groove and the main shaft body is 1-1.25 mm.

[0023] The beneficial effect of the present invention is that it can ensure that the shroud body can fit and seal with the main shaft body when the main shaft body is being repaired, thereby preventing the water level from flowing back into the machine pit due to a high level. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0025] Figure 1 It is a schematic diagram of the overall structure of the belt of the present invention.

[0026] Figure 2 It is a schematic diagram of the overall structure of the maintenance sealing structure of the present invention.

[0027] Figure 3 It is a schematic diagram of the overall structure of the main shaft sealing device of the present invention. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0029] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0030] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0031] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0032] Example 1, reference Figure 1 , which is the first embodiment of the present invention, provides a belt, which includes a belt body 101, which is a rubber ring arranged in an annular shape; an annular cavity 102 is arranged inside the belt body 101.

[0033] When the circumferential belt body 101 is extruded, the existence of the internal cavity 102 allows the circumferential belt body 101 to undergo a large deformation, thereby changing the area of ​​the contact portion therewith; wherein the cross-section of the cavity 102 may be circular, elliptical or polygonal.

[0034] When in use, the circumferential belt body 101 is sleeved on the surface of the object to be sealed, and the circumferential belt body 101 is deformed by being squeezed and brought into contact with the object to be sealed, thereby increasing the contact area between the two and improving the sealing effect.

[0035] Furthermore, an air inlet 103 communicating with the cavity 102 is provided on the belt body 101, and fluid, which may be gas or liquid, can be injected into the cavity 102 through the air inlet 103. When the fluid enters the cavity 102, the cavity 102 is expanded, thereby causing the belt body 101 to expand. When it is working, the expanded belt body 101 can contact the surface of the object to be sealed, and the expansion will also increase the contact area between the two, thereby improving the sealing effect.

[0036] Example 2, reference Figure 2 , which is a second embodiment of the present invention, provides a maintenance sealing structure, which includes a shroud and a mounting seat 201.

[0037] The mounting seat 201 is annularly arranged, a receiving groove 202 with a notch is arranged on the inner side of the mounting seat 201, and an air passage 203 is arranged on the mounting seat 201;

[0038] The shroud body 101 is located in the receiving groove 202 , and the end of the air passage 203 is connected to the air inlet 103 .

[0039] Fluid can be injected into the cavity 102 of the circumferential belt body 101 through the air passage 203, so that the circumferential belt body 101 expands in the receiving groove 202 and fits the inner wall of the receiving groove 202, while part of the fluid overflows from the notch of the receiving groove 202, and the overflowing part of the circumferential belt body 101 can play a contact sealing role.

[0040] Furthermore, the mounting seat 201 includes a base 201a and a pressure plate 201b. The mounting seat 201 and the base 201a are provided with grooves, and the grooves are spliced ​​into a receiving groove 202. The base 201a and the pressure plate 201b are fixed by bolts, and the air duct 203 is set on the base 201a.

[0041] The air channel 203 is located in the mounting seat 201 , and an air inlet nozzle 204 is provided at one end of the air channel 203 , so that fluid can be easily introduced into the air channel 203 through the air inlet nozzle 204 .

[0042] Furthermore, the width of the connection portion between the receiving groove 202 and the airway 203 is greater than the width of the notch, and the cross-section of the receiving groove 202 may be heart-shaped, triangular or teardrop-shaped, wherein the sharper portion of the cross-section is cut out to form a notch in the receiving groove 202. The receiving groove 202 can control the expansion extension length of the shroud body 101, so that the shroud body 101 can expand first and then extend in the receiving groove 202, ensuring that the shroud body 101 can return to the inside of the receiving groove 202 when it retracts.

[0043] Example 3, reference Figure 3 , which is a third embodiment of the present invention, provides a main shaft sealing device, which includes a maintenance sealing structure and a main shaft body 301, and a sealing body 302 arranged on the outside of the main shaft body 301.

[0044] The mounting seat 201 is arranged on the outer side of the main shaft and connected to the sealing body 302. The sealing body 302 is located above the mounting seat 201, and the two are connected by bolts.

[0045] When the mixed flow turbine is in operation, a small amount of water leakage will occur at the leak-proof ring of the runner top cover, and the water will leak out from the gap between the main shaft body 301 and the sealing body 302, thereby causing water accumulation on the top cover. In serious cases, it will flow into the water guide bearing and affect the operation of the water guide bearing. The sealing body 302 is provided with a drain port 303, which can drain the water accumulated on the top cover.

[0046] Among them, the gap between the sealing body 302 and the main shaft body 301 is 0.3-0.4mm, and a labyrinth seal is adopted;

[0047] Further, the gap between the receiving groove 202 and the main shaft body 301 is 1-1.25mm, and the gap between the notch of the receiving groove 202 and the main shaft body 301 is 1-1.25mm; when performing maintenance, a fluid is introduced into the airway 203, so that the fluid enters the cavity 102 to expand the shroud body 101, and the shroud body 101 first expands in the receiving groove 202 and contacts the inner wall of the receiving groove 202, and finally part of the shroud body 101 overflows from the notch of the receiving groove 202, thereby contacting the main shaft body 301 to achieve sealing;

[0048] The width of the connection between the receiving groove 202 and the airway 203 is greater than the width of the notch, which can control the expansion extension length of the belt body 101, so that the belt body 101 can expand first and then extend in the receiving groove 202, while ensuring that the belt body 101 can return to the inside of the receiving groove 202 when retracting, avoiding friction damage caused by continuous contact. At the same time, only one notch can increase the contact pressure between the belt body 101 and the main shaft body 301, further improving the sealing effect.

[0049] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A belt, characterized in that: include, The belt body (101) is a rubber ring arranged in an annular shape; An annular cavity (102) is provided inside the shroud body (101).

2. The belt according to claim 1, characterized in that: The shroud body (101) is provided with an air inlet (103) communicating with the cavity (102).

3. A maintenance seal structure comprising the shroud as claimed in claim 2, characterized in that: Also includes; A mounting seat (201) is arranged in an annular shape, a receiving groove (202) with a notch is arranged on the inner side of the mounting seat (201), and an air passage (203) is arranged on the mounting seat (201); The shroud body (101) is located in the accommodating groove (202), and the end of the air passage (203) is connected to the air inlet (103).

4. The maintenance seal structure according to claim 3, characterized in that: The mounting seat (201) comprises a base (201a) and a pressing plate (201b); grooves are provided on the mounting seat (201) and the base (201a); the grooves are spliced ​​to form the accommodating groove (202).

5. The maintenance seal structure according to claim 4, characterized in that: The air channel (203) is located in the mounting seat (201), and an air inlet nozzle (204) is provided at one end of the air channel (203).

6. The maintenance seal structure according to any one of claims 3 to 5, characterized in that: The width of the connection portion between the accommodating groove (202) and the airway (203) is greater than the width of the notch.

7. A main shaft sealing device comprising the maintenance sealing structure according to claim 6, characterized in that: It also includes a main shaft body (301), and a sealing body (302) arranged outside the main shaft body (301); The mounting seat (201) is arranged on the outside of the main shaft and connected to the sealing body (302).

8. The main shaft sealing device according to claim 7, characterized in that: The sealing body (302) is provided with a drainage port (303).

9. The main shaft sealing device according to claim 8, characterized in that: The gap between the sealing body (302) and the main shaft body (301) is 0.3-0.4 mm, and a labyrinth seal is adopted.

10. The main shaft sealing device according to any one of claims 7 to 9, characterized in that: The gap between the accommodating groove (202) and the main shaft body (301) is 1-1.25 mm.

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