Steam seal ring structure of steam turbine

Abstract

The utility model provides a steam seal ring structure of a steam turbine, which belongs to the technical field of steam seal rings and comprises a steam seal ring and a shaft seal sleeve, the steam seal ring consists of a plurality of groups of steam seal blocks, the shaft seal sleeve consists of a plurality of groups of shaft seal blocks, the shaft seal sleeve is mounted at the outer end of the steam seal ring, and butt joint grooves are arranged on the end surfaces of the steam seal blocks. According to the steam seal ring, the reeds on the end faces of the two groups of steam seal blocks are mutually clamped, the reeds can eliminate the sealing performance between the steam seal blocks during movement through self flexibility and mutual dragging and stretching, and in a free state, under the action of spring force, the two groups of steam seal blocks are in an open state and are far away from a rotor, so that the two groups of steam seal blocks are separated from the rotor during shutdown. And under the action of spring stress of the telescopic spring, the distance between the reeds is closer, and the reeds are clamped more tightly, so that a gap between the two groups of steam seal blocks is increased, the steam seal blocks are pushed to be away from the rotor, the radial gap between the steam seal and the rotor reaches the maximum value, and the problem of steam seal rub-impact can be effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of steam turbines, in particular to a steam seal ring structure of a steam turbine. Background Art

[0002] The steam seal ring of the steam turbine is an important part of the steam turbine. A certain gap must be left between the rotating and stationary parts of the steam turbine to prevent mutual friction. Therefore, a steam seal device must be installed. Its main function is to reduce steam leakage and improve the efficiency of the steam turbine.

[0003] It has been found in actual use that the existing steam seal ring has the following shortcomings:

[0004] Due to the large amount of steam leakage from the shaft seal (especially after the seal teeth are worn), the length of the heating section of the steam on the shaft increases, and the temperature also rises, which increases the expansion difference. The existing shaft seal sleeve and the seal ring correspond to each other in pairs. When they rotate radially, the connection seams between the shaft seal sleeve and the seal ring are easy to intersect with each other, and the high and low teeth of the boss on the shaft and the seal block are relatively displaced and fall over, resulting in an increase in the amount of gas leakage, which makes the sealing effect unable to be guaranteed;

[0005] In addition, when the steam turbine passes the critical speed during the start-up and shutdown process, the rotor amplitude is large, the radial installation clearance of the steam seal is small, and the steam seal teeth are easily worn. After the existing steam seal ring is installed, the steam seal clearance remains unchanged during operation without friction. In mild cases, the steam seal teeth will be worn, the steam seal clearance will be increased, and the heat loss will be increased. When the friction is serious, the steam seal teeth will be deformed, brittle or even broken.

[0006] Therefore, the present application provides a steam turbine seal ring structure to meet the demand. Utility Model Content

[0007] The utility model aims to solve the problems existing in the above-mentioned background technology and proposes a steam turbine steam seal ring structure.

[0008] The technical problem to be solved by the utility model is to provide a steam turbine steam seal ring structure to solve the problems of the existing steam turbine steam seal ring structure.

[0009] In order to solve the above technical problems, the utility model provides the following technical solutions:

[0010] A steam seal ring structure for a steam turbine comprises: a steam seal ring and a shaft seal sleeve, wherein the steam seal ring is composed of a plurality of steam seal blocks, and the shaft seal sleeve is composed of a plurality of shaft seal blocks. The outer end of the steam seal ring is provided with a shaft seal sleeve, the end face of the steam seal block is provided with a docking groove, the side face of the steam seal block is provided with a clamping groove, a reed is installed in the docking groove of the steam seal block, a telescopic spring is installed at the bottom of the reed, a docking block is provided on the side face of the shaft seal block, an installation groove is provided on the outer surface of the shaft seal block, and a connecting piece and a fixing bolt are installed in the installation groove of the shaft seal block.

[0011] Preferably, the steam seal ring as a whole is composed of two equally divided arc-shaped steam seal blocks connected end to end and surrounded, and the shaft seal sleeve as a whole is composed of three equally divided shaft seal blocks connected end to end and surrounded.

[0012] Preferably, the connecting seams between the shaft sealing blocks are staggered with the connecting seams between the steam sealing blocks.

[0013] Preferably, rectangular docking grooves are provided at both ends of the steam seal block, and the spring leaves extend outward to the outer ends of the docking grooves.

[0014] Preferably, a trapezoidal locking tooth is provided at the front end of the spring sheet, and the steam seal ring is mutually locked by the spring sheets on the end faces of the two groups of steam seal blocks.

[0015] Preferably, the telescopic spring is vertically installed at the bottom of the spring leaf, and the other end of the telescopic spring is in contact with the inner wall of the docking groove.

[0016] Preferably, the docking block is located on the inner side of the shaft sealing block, the docking block and the slot are both arc-shaped, and the docking block is embedded in the slot and fits with the slot.

[0017] Preferably, the docking block extends outward to the outer end of the groove of the steam sealing ring, and the connecting piece and the fixing bolt are located at the outer end of the steam sealing ring.

[0018] Compared with the prior art, the utility model has at least the following beneficial effects:

[0019] 1. The steam seal ring is composed of two equally divided arc-shaped steam seal blocks connected end to end, and the shaft seal sleeve is composed of three equally divided shaft seal blocks connected end to end. This can prevent the rotor amplitude from being large when the steam turbine exceeds the critical speed during the start-up and shutdown process, which makes the stress of the steam seal large when it moves radially, thereby ensuring a large gap and reducing the wear of the steam seal teeth. The connection seams between the shaft seal blocks are staggered with the connection seams between the steam seal blocks. The butt joint block of the shaft seal block is inserted into the groove of the steam seal block, which can eliminate the connection seam between the steam seal ring and the shaft seal sleeve, avoid the connection seams corresponding to each other, avoid relative displacement and lodging, and increase the leakage, thereby ensuring the sealing effect;

[0020] 2. The steam seal rings are connected to each other through the springs on the end faces of the two sets of steam seal blocks. The springs are stretched by their own elasticity and can eliminate the sealing between the steam seal blocks when moving. In the free state, under the action of the spring force, the two sets of steam seal blocks are in an open state and away from the rotor. When the machine is stopped, under the action of the spring stress of the telescopic spring, the distance between the springs is closer and the clamping is tighter, which increases the gap between the two sets of steam seal blocks, pushes the steam seal blocks away from the rotor, and makes the radial clearance between the steam seal and the rotor reach the maximum value, which can effectively reduce the problem of steam seal collision. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which are incorporated herein and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, further serve to explain the principles of the present disclosure and to enable those skilled in the relevant art to make and use the present disclosure.

[0022] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0023] Figure 2 This is a schematic diagram of the disassembled structure of the steam seal ring and the shaft seal sleeve of the utility model;

[0024] Figure 3 This is a schematic diagram of the specific structure of the steam seal block of the utility model;

[0025] Figure 4 This is a schematic diagram of the specific structure of the shaft seal block of the utility model;

[0026] Figure 5 It is a schematic diagram of the cross-sectional structure of the steam seal ring of the utility model.

[0027] [reference numerals]

[0028] 1-steam seal ring; 2-shaft seal sleeve; 3-spring; 4-telescopic spring; 5-docking block; 6-connecting plate; 7-fixing bolt; 101-steam seal block; 201-shaft seal block; 1011-docking groove; 1012-card slot; 2011-installation groove.

[0029] As shown in the figure, in order to clearly implement the structure of the embodiment of the utility model, specific structures and devices are marked in the figure, but this is only for illustrative purposes and is not intended to limit the utility model to the specific structure, device and environment. According to specific needs, ordinary technicians in this field can adjust or modify these devices and environments, and the adjustments or modifications made are still included in the scope of the attached claims. DETAILED DESCRIPTION

[0030] like Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5A steam turbine steam seal ring structure is shown in an embodiment of the utility model, comprising: a steam seal ring 1 and a shaft seal sleeve 2, the steam seal ring 1 is composed of a plurality of steam seal blocks 101, the shaft seal sleeve 2 is composed of a plurality of shaft seal blocks 201, the outer end of the steam seal ring 1 is installed with the shaft seal sleeve 2, the end face of the steam seal block 101 is provided with a docking groove 1011, the side of the steam seal block 101 is provided with a clamping groove 1012, the steam seal block 101 is provided with a reed 3 installed in the docking groove 1011, the bottom of the reed 3 is provided with a telescopic spring 4, the side of the shaft seal block 201 is provided with a docking block 5, the outer surface of the shaft seal block 201 is provided with a mounting groove 2011, and the shaft seal block 201 is provided with a connecting piece 6 and a fixing bolt 7 in the mounting groove 2011.

[0031] In this embodiment, the steam seal ring 1 as a whole is composed of two equally divided arc-shaped steam seal blocks 101 connected end to end and surrounded, and the shaft seal sleeve 2 as a whole is composed of three equally divided shaft seal blocks 201 connected end to end and surrounded. This can prevent the rotor amplitude from being large when the steam turbine exceeds the critical speed during the start-up and shutdown process, resulting in a large stress on the steam seal when it moves radially, thereby ensuring a large gap and reducing the wear of the steam seal teeth.

[0032] In this embodiment, the connection seams between the shaft seal blocks 201 and the connection seams between the steam seal blocks 101 are staggered, which can avoid the connection seams from corresponding to each other, avoid relative displacement and collapse, and increase the air leakage, thereby ensuring the sealing effect.

[0033] In this embodiment, rectangular docking grooves 1011 are provided at both ends of the steam sealing block 101, and the spring leaves 3 extend outward to the outer ends of the docking grooves 1011. During installation, the two sets of steam sealing blocks 101 can be docked end to end, and the spring leaves 3 can move elastically, and by pressing the telescopic springs 4, the spring leaves 3 at both ends are clamped with each other in the docking grooves 1011.

[0034] In this embodiment, a trapezoidal locking tooth is provided at the front end of the reed 3, and the steam seal ring 1 is mutually engaged through the reeds 3 on the end faces of the two groups of steam seal blocks 101. The reeds 3 can eliminate the sealing between the steam seal blocks 101 when moving due to their own elasticity and mutual traction and stretching. In the free state, under the action of the spring force, the two groups of steam seal blocks 101 are in an open state and away from the rotor, so that when the machine is stopped, under the action of the spring stress of the telescopic spring 4, the distance between the reeds 3 is closer and the clamping is tighter, so that the gap between the two groups of steam seal blocks 101 is increased, pushing the steam seal blocks 101 away from the rotor, so that the radial clearance between the steam seal and the rotor reaches the maximum value, which can effectively reduce the problem of steam seal collision.

[0035] In this embodiment, the telescopic spring 4 is vertically installed at the bottom of the spring leaf 3, and the other end of the telescopic spring 4 is in contact with the inner wall of the docking groove 1011. The telescopic spring 4 can provide support for the spring leaf 3 and enable the spring leaf 3 to move.

[0036] In this embodiment, the docking block 5 is located on the inner side of the shaft sealing block 201, and the docking block 5 and the slot 1012 are both arc-shaped, and the docking block 5 is embedded in the slot 1012 and fits between the slots 1012. During installation, the docking block 5 of the shaft sealing block 201 can be directly inserted into the slot 1012 of the steam sealing block 101 to complete the docking installation of the shaft sealing block 201 and the steam sealing block 101.

[0037] In this embodiment, the docking block 5 extends outward to the outer end of the slot 1012 of the steam seal ring 1, and the connecting piece 6 and the fixing bolt 7 are located at the outer end of the steam seal ring 1, making installation and disassembly more convenient.

Claims

1. A steam turbine seal ring structure, characterized in that: include: A steam seal ring (1) and a shaft seal sleeve (2), wherein the steam seal ring (1) is composed of a plurality of steam seal blocks (101), and the shaft seal sleeve (2) is composed of a plurality of shaft seal blocks (201). The shaft seal sleeve (2) is installed at the outer end of the steam seal ring (1), a docking groove (1011) is provided on the end surface of the steam seal block (101), a clamping groove (1012) is provided on the side surface of the steam seal block (101), a spring leaf (3) is installed in the docking groove (1011) of the steam seal block (101), a telescopic spring (4) is installed at the bottom of the spring leaf (3), a docking block (5) is installed on the side surface of the shaft seal block (201), an installation groove (2011) is provided on the outer surface of the shaft seal block (201), and a connecting piece (6) and a fixing bolt (7) are installed in the installation groove (2011) of the shaft seal block (201).

2. The steam turbine seal ring structure according to claim 1, characterized in that: The steam seal ring (1) as a whole is composed of two equally divided arc-shaped steam seal blocks (101) connected end to end and surrounding each other, and the shaft seal sleeve (2) as a whole is composed of three equally divided shaft seal blocks (201) connected end to end and surrounding each other.

3. The steam turbine seal ring structure according to claim 1, characterized in that: The connecting seams between the shaft sealing blocks (201) and the connecting seams between the steam sealing blocks (101) are staggered.

4. The steam turbine seal ring structure according to claim 1, characterized in that: Rectangular butt joint grooves (1011) are provided at both ends of the steam seal block (101), and the spring leaf (3) extends outward to the outer end of the butt joint groove (1011).

5. The steam turbine seal ring structure according to claim 1, characterized in that: The front end of the spring sheet (3) is provided with a trapezoidal locking tooth, and the steam seal ring (1) is mutually locked through the spring sheets (3) on the end surfaces of the two groups of steam seal blocks (101).

6. The steam turbine seal ring structure according to claim 1, characterized in that: The telescopic spring (4) is vertically mounted on the bottom of the spring leaf (3), and the other end of the telescopic spring (4) is in contact with the inner wall of the docking groove (1011).

7. The steam turbine seal ring structure according to claim 1, characterized in that: The docking block (5) is located on the inner side of the shaft sealing block (201); the docking block (5) and the slot (1012) are both in an arc shape; and the docking block (5) is embedded in the slot (1012) and fits in with the slot (1012).

8. The steam turbine seal ring structure according to claim 1, characterized in that: The docking block (5) extends outward to the outer end of the clamping groove (1012) of the steam seal ring (1), and the connecting piece (6) and the fixing bolt (7) are located at the outer end of the steam seal ring (1).

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