Bearing lubricating oil sealing structure

Abstract

The utility model relates to a bearing lubricating oil sealing structure, which belongs to the technical field of lubrication and comprises a rotating shaft and a bearing cover sleeved outside the rotating shaft, a vent valve is mounted on the outer circumferential surface of the bearing cover, an oil cavity is arranged between the inner wall and the outer wall of the bearing cover, and a vent hole is arranged on the inner wall of the bearing cover. The ventilation hole is communicated with an oil cavity between the inner wall of the bearing cover and the outer wall of the bearing cover, and an oil retainer, an air guide ring fixed on the bearing cover and a miniature fan formed by a plurality of L-shaped chutes on the rotating shaft are arranged on the inner circumferential surface of the bearing cover. The miniature fan generates air pressure higher than the air pressure in the bearing cavity at the oil retainer, the bearing cavity is connected with the outside through the vent valve, and the air pressure sequence is that the air pressure at the oil retainer is larger than the air pressure in the bearing cavity is larger than the air pressure at the vent valve, so that the problem that the air pressure at the oil retainer is low in a conventional structure is solved, and the problem of lubricating oil leakage caused by the air pressure is fundamentally solved; and potential safety hazards are greatly reduced.

Description

Technical Field

[0001] The utility model relates to a lubricating oil sealing structure for bearings, belonging to the technical field of lubrication. Background Art

[0002] A steam turbine generator refers to a generator driven by a steam turbine. Superheated steam generated by a boiler enters the steam turbine to expand and do work, causing the blades to rotate and drive the generator to generate electricity. The exhausted steam after doing work is sent back to the boiler for recycling through a condenser, a circulating water pump, a condensate pump, a feedwater heating device, etc.

[0003] When a steam turbine generator is in operation, the rotation speed of the rotating shaft is relatively high, and lubrication between the rotating shaft and the bearing is indispensable. Lubricating oil sealing is an important technology. During the operation of the unit, the temperature of the lubricating oil is relatively high and it will continuously atomize, causing the air pressure in the bearing cavity to be higher than the atmospheric pressure, resulting in the lubricating oil leaking out along the rotating shaft through the oil retaining ring with lower air pressure to the outside of the bearing. Long-term operation will form oil stains and sludge at the rotating shaft and the bearing cover, damaging the bearing insulation and causing the shaft voltage to break through the oil film, resulting in significant property losses. The common practice in the prior art is to install a vent valve on the bearing seat to balance the high air pressure in the bearing cavity and reduce the air pressure driving force for the external leakage of the lubricating oil. However, it is found during the actual operation process that due to vibration, the oil retaining ring and the rotating shaft are not tightly fitted, and this is also a place with relatively low air pressure, and the lubricating oil can still leak here. Therefore, the conventional method of installing a vent valve cannot fundamentally solve the leakage problem and there will still be potential safety hazards. Therefore, it is necessary to design a new oil seal structure to fundamentally solve this problem. Summary of the Utility Model

[0004] The purpose of the utility model is to solve the technical problems of easy leakage of lubricating oil and relatively large potential safety hazards existing in the prior art, and provide a lubricating oil sealing structure for bearings.

[0005] The utility model is realized through the following technical solutions:

[0006] That is, a lubricating oil sealing structure for bearings includes a rotating shaft and a bearing cover sleeved outside the rotating shaft. A vent valve is installed on the outer circumferential surface of the bearing cover. There is an oil cavity between the inner wall and the outer wall of the bearing cover. An air vent hole is opened on the inner wall of the bearing cover, and the air vent hole is communicated with the oil cavity between the inner wall and the outer wall of the bearing cover. An oil retaining ring is installed on the inner circumferential surface of the bearing cover;

[0007] Several L-shaped inclined grooves are opened on the rotating shaft. The windward surface of the L-shaped inclined groove is a vertical surface, and the bottom side is an arc surface or a plane. When the rotating shaft rotates, the several L-shaped inclined grooves form a miniature axial flow fan.

[0008] The micro - fan composed of several L - shaped inclined grooves on the rotating shaft generates a higher air pressure at the oil baffle ring than in the bearing cavity. The bearing cavity is connected to the outside through a ventilation valve. Thus, the air pressure sequence is: air pressure at the oil baffle ring > bearing cavity > ventilation valve. This changes the problem of lower air pressure at the oil baffle ring in the conventional structure, and fundamentally solves the problem of lubricating oil leakage caused by air pressure, greatly reducing the safety hazard.

[0009] Further preferably, one oil baffle ring is installed on the inner circumferential surface of the outer wall of the bearing cover, and two oil baffle rings are installed on the inner circumferential surface of the inner wall of the bearing cover.

[0010] Further preferably, a wind guide ring is installed on the outer end face of the bearing cover. The wind guide ring keeps a certain gap with the rotating shaft, and this gap can be adjusted according to different bearings and application conditions to ensure meeting the head requirement of the fan.

[0011] Compared with the prior art, the beneficial effects of the present utility model are:

[0012] The micro - fan composed of several L - shaped inclined grooves on the rotating shaft generates a higher air pressure at the oil baffle ring than in the bearing cavity. The bearing cavity is connected to the outside through a ventilation valve. Thus, the air pressure sequence is: air pressure at the oil baffle ring > bearing cavity > ventilation valve. This changes the problem of lower air pressure at the oil baffle ring 5 in the conventional structure, and fundamentally solves the problem of lubricating oil leakage caused by air pressure, greatly reducing the safety hazard. Further preferably, several inclined grooves are opened on the rotating shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the present utility model, the drawings required for description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0014] Figure 1 It is a three - dimensional structure schematic diagram of the specific embodiment of the present utility model.

[0015] In the figure: 1. Bearing cover; 2. Rotating shaft; 3. Inner wall of the bearing cover; 4. Ventilation hole; 5. Oil baffle ring; 6. Outer wall of the bearing cover; 7. Wind guide ring; 8. Oil - throwing groove; 9. Inclined groove; 10. Ventilation valve. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0016] The following further details the specific embodiments of the present utility model with reference to the drawings.

[0017] As Figure 1A bearing lubricating oil sealing structure as shown includes a rotating shaft 2 and a bearing cover 1 sleeved outside the rotating shaft 2. There are two annular oil slinging grooves 8 on the rotating shaft 2. An air vent valve 10 is installed on the outer circumferential surface of the bearing cover 1. There is an oil cavity between the inner wall 3 and the outer wall 6 of the bearing cover 1. An air vent hole 4 is opened on the inner wall 3 of the bearing cover 1, and the air vent hole 4 communicates with the oil cavity between the inner wall 3 and the outer wall 6 of the bearing cover 1. A oil retaining ring 5 is installed on the inner circumferential surface of the bearing cover 1;

[0018] A number of L-shaped inclined grooves 9 are opened on the rotating shaft 2. The windward surface of the L-shaped inclined groove 9 is a vertical surface, and the bottom side is a plane or an arc surface. When the rotating shaft 2 rotates, the number of L-shaped inclined grooves 9 forms a miniature axial flow fan, increasing the air pressure at the bearing cover 1 and the rotating shaft 2. The number and size of the L-shaped inclined grooves 9 should be determined according to the bearing size and the pressure in the bearing cavity generated by the lubricating oil temperature. After calculation, the air pressure generated by the miniature fan should be slightly greater than the air pressure in the bearing cavity.

[0019] The miniature fan composed of a number of L-shaped inclined grooves 9 on the rotating shaft 2 generates an air pressure higher than that in the bearing cavity at the oil retaining ring 5. The bearing cavity is connected to the outside through the air vent valve 10. Thus, the air pressure sequence is: the air pressure at the oil retaining ring 5 > the bearing cavity > the air pressure at the air vent valve 10, changing the problem of lower air pressure at the oil retaining ring 5 in the conventional structure, and fundamentally solving the problem of lubricating oil leakage caused by air pressure reasons, greatly reducing the potential safety hazards.

[0020] Among them, an oil retaining ring 5 is installed on the inner circumferential surface of the outer wall 6 of the bearing cover, and two oil retaining rings 5 are installed on the inner circumferential surface of the inner wall 3 of the bearing cover.

[0021] Among them, a wind guiding ring 7 is installed on the outer end surface of the bearing cover 1. The wind guiding ring 7 maintains a certain gap with the rotating shaft 2, and this gap can be adjusted according to different bearings and application conditions to ensure meeting the head requirements of the fan.

[0022] Working principle:

[0023] The miniature fan composed of a number of L-shaped inclined grooves 9 on the rotating shaft 2 generates an air pressure higher than that in the bearing cavity at the oil retaining ring 5. The bearing cavity is connected to the outside through the air vent valve 10. Thus, the air pressure sequence is: the air pressure at the oil retaining ring 5 > the bearing cavity > the air pressure at the air vent valve 10, changing the problem of lower air pressure at the oil retaining ring 5 in the conventional structure, and fundamentally solving the problem of lubricating oil leakage caused by air pressure reasons, greatly reducing the potential safety hazards.

[0024] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same and similar parts among the embodiments, reference can be made to each other.

[0025] In the description, claims and above-mentioned drawings of the present utility model, terms such as "upper", "lower", "outer side", "inner side", etc., if any, are used to distinguish the relative relationship in position and do not have to be given a qualitative definition. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present utility model described herein can be implemented in an order different from those illustrated or described herein. In addition, the terms "comprise" and "have" and any variations thereof are intended to cover non-exclusive inclusion.

[0026] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present utility model. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present utility model. Therefore, the present utility model will not be limited to the embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A bearing lubricating oil sealing structure, comprising a rotating shaft (2) and a bearing cover (1) sleeved on the rotating shaft (2), characterized in that: A vent valve (10) is mounted on the outer circumferential surface of the bearing cover (1); an oil cavity between the bearing cover inner wall (3) and the bearing cover outer wall (6) of the bearing cover (1); a vent hole (4) is opened on the bearing cover inner wall (3); the vent hole (4) is connected to the oil cavity between the bearing cover inner wall (3) and the bearing cover outer wall (6); an oil retaining ring (5) is mounted on the inner circumferential surface of the bearing cover (1); A plurality of L-shaped inclined grooves (9) are provided on the rotating shaft (2); the windward surface of the L-shaped inclined grooves (9) is a vertical surface, and the bottom side is an arc surface or a plane surface; the plurality of L-shaped inclined grooves (9) form a miniature axial flow fan when the rotating shaft (2) rotates.

2. A bearing lubricating oil sealing structure according to claim 1, characterized in that: An oil retaining ring (5) is mounted on the inner circumferential surface of the outer wall (6) of the bearing cover, and two oil retaining rings (5) are mounted on the inner circumferential surface of the inner wall (3) of the bearing cover.

3. A bearing lubricating oil sealing structure according to claim 1, characterized in that: An air guide ring (7) is mounted on the outer end surface of the bearing cover (1).

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