Self-adjusting radial sealing device for water turbine

Abstract

The utility model discloses a self-adjusting type radial sealing device for a water turbine, which comprises a base plate, a sealing plate, a sealing plug and a gland, a flange is arranged on the outer side of a main shaft, the base plate is detachably connected with the flange, and the sealing plate is fixed on the base plate. The sealing plug is of a hollow structure, is filled with lubricating water and is arranged between the gland and the sealing plate, and a circulating lubricating system is formed through the first water injection hole and the second water injection hole. The sealing plug is formed by splicing a plurality of sealing blocks provided with clamping grooves and clamping rails, and the lower end of the sealing plug is clamped in the sliding groove of the sealing plate. The gland is provided with a containing groove matched with a positioning pin at the upper end of the sealing plug for limiting. Through the modular sealing block design and a dual-lubrication system, self-adaptive adjustment and continuous lubrication of a sealing interface are achieved, the device has the advantages of being simple in structure, stable in sealing performance, long in service life, convenient to maintain and the like, and the technical problems that a traditional sealing device is fast in abrasion and difficult to maintain are effectively solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of hydropower station engineering equipment, especially a self-adjusting radial sealing device for a water turbine. BACKGROUND

[0002] In the main shaft sealing technology of the water turbine, the traditional scheme mainly includes two kinds of packing packing type and flat plate sealing type. The packing packing type relies on the compression sealing of flexible packing, although the structure is simple, but the packing is easy to wear and needs to be replaced frequently, and the friction generates heat easily leading to failure, and the adaptability to the main shaft vibration is poor. The flat plate sealing type is shown in the patent with publication number CN218063396U, the sealing piston is compressed on the contact plane of the wear plate by the gland, and the sealing piston is limited from rotating with the main shaft by the limiting structure, although the packing wear problem is alleviated, but the gap between the inner wall of the sealing piston and the main shaft still exists the risk of dynamic leakage, and the lubricating water is easy to seep into and erode the main shaft.

[0003] Further, the contact surface of the sealing piston and the wear plate in the scheme is irreversibly worn due to long-term friction, the sealing pressure gradually decreases, and the pre-tightening force of the gland needs to be repeatedly adjusted, and the overall sealing piston is difficult to replace and has high cost. In addition, the rigidity sealing design is not suitable for the adaptability of the main shaft movement and jumping, and is easy to cause sudden leakage due to vibration. The existing technology generally faces the bottlenecks of low dynamic sealing reliability, lack of wear self-compensation ability and low maintenance efficiency, and needs to be improved. UTILITY MODEL CONTENTS

[0004] The technical problem to be solved by the utility model is to provide a self-adjusting radial sealing device for a water turbine, which has dynamic sealing reliability, wear self-compensation ability and modular maintenance convenience, and can fully solve the above problems.

[0005] To solve the above technical problems, the utility model adopts the technical scheme of:

[0006] A self-adjusting radial sealing device for a water turbine, comprising a base plate, a sealing plate, a sealing plug and a gland, a flange is arranged at the outer wall of the main shaft, the base plate and the sealing plate are sleeved at the outer wall of the main shaft, the base plate is detachably connected with the flange, the upper end surface of the base plate is fixedly connected with the sealing plate, the sealing plug and the gland are further sleeved at the outer wall of the main shaft, the sealing plug is arranged between the gland and the sealing plate, the sealing plug is a hollow structure and is injected with lubricating water, and a limiting mechanism is arranged between the sealing plug and the gland.

[0007] In the preferred scheme, a containing groove is formed at the bottom surface of the gland, the upper end surface of the sealing plug is inserted into the containing groove, and a second water injection hole is formed through between the upper end surface of the gland and the containing groove.

[0008] In the preferred solution, the limiting mechanism comprises a positioning pin and a positioning groove, the upper end surface of the sealing plug is annularly provided with the positioning pin, and the inner side surface of the accommodating groove is correspondingly provided with the positioning groove, the positioning pin and the positioning groove are inserted into each other and keep the relative fixation between the gland and the sealing plug.

[0009] In the preferred solution, the flange and the base plate are detachably connected through a fastening bolt, and the fastening bolt is circumferentially arranged along the main shaft axis.

[0010] In the preferred solution, the sealing plug is spliced by a plurality of sealing blocks, one side of the sealing block is provided with a clamping groove, the other side of the sealing block is correspondingly provided with a clamping rail, and the plurality of sealing blocks are inserted into each other through the clamping groove and the clamping rail to form an annular sealing plug.

[0011] In the preferred solution, the sealing block is of an inner hollow structure, and a first water injection hole is vertically and communicatively arranged on the outer wall of the sealing block.

[0012] In the preferred solution, an annular sliding groove is arranged at the upper end surface of the sealing plate, and the lower end surface of the sealing block is clamped in the sliding groove and limited to slide along the sliding groove.

[0013] A self-adjusting radial sealing device for a water turbine has the following beneficial effects:

[0014] 1. The sealing plug is of an inner hollow structure and is injected with lubricating water, and a lubricating water film is formed through the first water injection hole, which can not only reduce the friction coefficient between the sealing block and the main shaft and between the sealing block and the sealing plate, but also can adaptively compensate for the gap change of the sealing interface by using the water film pressure to effectively inhibit dynamic leakage.

[0015] 2. The sealing plug and the gland are inserted and limited by the positioning pin and the positioning groove, which ensures that the sealing plug remains relatively stationary with the main shaft during operation, completely avoids the eccentric wear problem caused by the rotation of the sealing member with the main shaft, and at the same time allows the sealing block to slightly float radially in the sliding groove to adapt to the axial movement and radial runout of the main shaft, thereby improving the sealing stability.

[0016] 3. The annular sealing plug composed of a plurality of sealing blocks is formed by the insertion and cooperation of the clamping groove and the clamping rail to form a flexible sealing ring, which can uniformly fit the sealing plate and the main shaft surface under pressure to avoid abnormal wear caused by local stress concentration.

[0017] 4. The lubricating water circulates in the internal cavity of the sealing block, continuously removes the friction heat and supplements the water loss due to slight leakage, realizes self-cooling and self-lubrication of the sealing interface, and significantly prolongs the service life of the sealing member.

[0018] 5、Split seal block design allows individual replacement of damaged sealing unit, without disassembling the gland, base plate and other main structure, greatly shorten the maintenance downtime; the flange and the base plate are connected through the circumferentially distributed fastening bolts, and cooperate with the detachable seal plate, simplify the replacement process of the wear-resistant components, and reduce the operation and maintenance cost. BRIEF DESCRIPTION OF DRAWINGS

[0019] The utility model will be further described below in combination with the drawings and embodiments:

[0020] Figure 1 It is the whole structure plane schematic diagram of the utility model;

[0021] Figure 2 It is the sealing plug installation effect schematic diagram of the utility model;

[0022] Figure 3 It is the sealing block structure schematic diagram of the utility model;

[0023] Figure 4 It is the bottom structure of the utility model gland upside down view.

[0024] In the drawing: main shaft 1, base plate 2, sealing plate 3, sliding slot 31, sealing plug 4, sealing block 41, first water injection hole 42, clamping groove 43, clamping rail 44, gland 5, containing groove 51, positioning groove 52, positioning pin 6, second water injection hole 7, fastening bolt 8, lubricating water 9, flange 10. DETAILED DESCRIPTION

[0025] As shown in Figure 1 A self-adjusting type radial sealing device for water turbine, including base plate 2, sealing plate 3, sealing plug 4 and gland 5, the outer wall of main shaft 1 is provided with flange 10, base plate 2 and sealing plate 3 are sleeved on the outer wall of main shaft 1, base plate 2 and flange 10 are detachably connected, which is convenient for on-site installation and maintenance, the upper end surface of base plate 2 is fixedly connected (such as welded or bolted) with sealing plate 3, forming the fixed support structure of sealing device;

[0026] The outer wall of main shaft 1 is also sleeved with sealing plug 4 and gland 5, sealing plug 4 is arranged between gland 5 and sealing plate 3, sealing plug 4 is hollow structure and injects lubricating water 9, and limiting mechanism is arranged between sealing plug 4 and gland 5. Realize the relative static of sealing plug 4 and main shaft 1, effectively solve the wear problem caused by insufficient lubrication of traditional sealing device.

[0027] Preferred scheme as Figure 1 And Figure 4As shown, the bottom surface of the gland 5 is provided with a receiving groove 51, and the upper end surface of the sealing plug 4 is inserted into the receiving groove 51. A second water injection hole 7 is formed between the upper end surface of the gland 5 and the receiving groove 51. This design allows external pressure water to flow through the second water injection hole 7 and press the sealing plug 4 against the sealing plate 3, so that the lower end surface of the sealing plug 4 tightly contacts the upper surface of the sealing plate 3. At the same time, the sealing plug 4 is allowed to slightly slide along the surface of the sealing plate 3 when the main shaft 1 radially jumps, so as to adaptively adjust the sealing gap. The external pressure water refers to water with external water pressure, which is not described herein

[0028] The preferred scheme is as shown in Figures 1 to 3 As shown, the limiting mechanism includes a positioning pin 6 and a positioning groove 52. The upper end surface of the sealing plug 4 is annularly provided with the positioning pin 6, and the inner surface of the receiving groove 51 is correspondingly provided with the positioning groove 52. The positioning pin 6 and the positioning groove 52 are inserted into each other to keep the gland 5 and the sealing plug 4 relatively fixed. This design ensures that the sealing plug 4 remains stationary when the main shaft 1 rotates at high speed, avoiding the eccentric wear of the sealing surface due to circumferential friction. At the same time, the sealing plug 4 is allowed to slightly float along the axial direction of the main shaft 1 to adapt to the axial movement of the main shaft 1.

[0029] The preferred scheme is as shown in Figure 1 As shown, the flange 10 and the base plate 2 are detachably connected through fastening bolts 8 arranged circumferentially along the axis of the main shaft 1. This connection mode not only ensures the stability of the structure, but also facilitates the installation and maintenance of the device, greatly improving the convenience of use.

[0030] The preferred scheme is as shown in Figure 2 and Figure 3 As shown, the sealing plug 4 is composed of a plurality of sealing blocks 41. One side of the sealing block 41 is provided with a clamping groove 43, and the other side of the sealing block 41 is correspondingly provided with a clamping rail 44. The plurality of sealing blocks 41 are inserted into each other through the clamping groove 43 and the clamping rail 44 to form an annular sealing plug 4. This split design allows the sealing plug 4 to uniformly adhere to the surface of the main shaft 1 and the sealing plate 3 when under pressure, avoiding local stress concentration caused by manufacturing errors of the integral sealing member. When a single sealing block 41 is worn or damaged, it can be individually disassembled and replaced without the need to disassemble the entire sealing device, greatly reducing maintenance costs.

[0031] The preferred scheme is as shown in Figure 2 and Figure 3 As shown, the sealing block 41 has an inner hollow structure, and the outer wall of the sealing block 41 is vertically and continuously provided with a first water injection hole 42. This design allows lubricating water 9 to be evenly distributed to each part of the sealing block 41 through the first water injection hole 42. The injection water pressure of the lubricating water 9 is higher than the external pressure, so that a lubricating water film with pressure is formed between the sealing block 41 and the main shaft 1, achieving real-time sealing, lubrication and cooling effects of the main shaft 1.

[0032] The preferred scheme is as shown in Figure 3 As shown, the upper end face of the sealing plate 3 is provided with an annular sliding groove 31, and the lower end face of the sealing block 41 is clamped in the sliding groove 31 and slides along the sliding groove 31. This structure synchronously adjusts the position of the sealing block 41 when the main shaft 1 radially jumps, keeps the whole sealing surface adhered, limits the circumferential rotation of the sealing block 41, and ensures the sealing stability.

Claims

1. A self-adjusting radial seal device for hydraulic turbines, comprising a base plate (2), a seal plate (3), a seal plug (4) and a gland (5), characterized in that: The outer wall of the main shaft (1) is provided with a flange (10), the base plate (2) and the sealing plate (3) are sleeved on the outer wall of the main shaft (1), the base plate (2) is detachably connected with the flange (10), the upper end surface of the base plate (2) is fixedly connected with the sealing plate (3), the outer wall of the main shaft (1) is further sleeved with a sealing plug (4) and a gland (5), the sealing plug (4) is arranged between the gland (5) and the sealing plate (3), the sealing plug (4) is of an inner hollow structure and is injected with lubricating water (9), and a limiting mechanism is arranged between the sealing plug (4) and the gland (5).

2. The self-adjusting radial seal device for hydraulic turbines according to claim 1, characterized in that: The bottom surface of the gland (5) is provided with a containing groove (51), the upper end surface of the sealing plug (4) is inserted into the containing groove (51), and the second water injection hole (7) is formed through the upper end surface of the gland (5) and the containing groove (51).

3. The self-adjusting radial seal device for hydraulic turbines according to claim 2, characterized in that: The limiting mechanism comprises a positioning pin (6) and a positioning groove (52), the upper end surface of the sealing plug (4) is annularly provided with the positioning pin (6), the inner side surface of the containing groove (51) is correspondingly provided with the positioning groove (52), the positioning pin (6) and the positioning groove (52) are inserted into each other, and the gland (5) and the sealing plug (4) are relatively fixed.

4. The self-adjusting radial seal device for hydraulic turbines according to claim 1, characterized in that: The flange (10) and the base plate (2) are detachably connected through the fastening bolt (8), and the fastening bolt (8) is circumferentially arranged along the axis of the main shaft (1).

5. The self-adjusting radial seal device for hydraulic turbines according to claim 1, characterized in that: The sealing plug (4) is composed of a plurality of sealing blocks (41), one side of the sealing block (41) is provided with a clamping groove (43), the other side of the sealing block (41) is correspondingly provided with a clamping rail (44), and the plurality of sealing blocks (41) are inserted into each other through the clamping groove (43) and the clamping rail (44) and form the annular sealing plug (4).

6. The self-adjusting radial seal device for hydraulic turbines according to claim 5, characterized in that: The sealing block (41) is of an inner hollow structure, and the first water injection hole (42) is vertically and communicatively arranged on the outer wall of the sealing block (41).

7. The self-adjusting radial seal device for hydraulic turbines according to claim 5, characterized in that: The upper end surface of the sealing plate (3) is provided with an annular sliding groove (31), and the lower end surface of the sealing block (41) is clamped in the sliding groove (31) and is limited to slide along the sliding groove (31).

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