Center-adjustable middle steam seal with dehumidification function

Abstract

The invention discloses a center-adjustable middle steam seal with a dehumidification function. The center-adjustable middle steam seal comprises a steam turbine cylinder body and a steam turbine rotor. The middle steam seal is arranged between the steam turbine cylinder body and the steam turbine rotor, convex lugs are arranged on the two sides of the middle steam seal, and a guide pin hole is formed in the front portion of the middle steam seal; one end of the eccentric guide pin penetrates through the guide pin hole and is arranged on the channel, and the eccentric guide pin comprises an eccentric pin and an eccentric sleeve matched with the eccentric pin; one end of the adjusting element is connected to the convex lug, the other end of the adjusting element is located on the steam turbine cylinder body, the adjusting element comprises a spherical gasket, adjusting nuts and a screw, the screw is in threaded fit with at least one adjusting nut, and the adjusting nuts are in threaded fit with the convex lug; the spherical gasket is arranged at one end of the adjusting nut; according to the middle steam seal, the dehumidification effect can be achieved, the center position of the middle steam seal can be adjusted under the cooperation of the eccentric guide pin and the adjusting element, the center adjusting function of the middle steam seal is achieved, the radial clearance and the dehumidification capacity are guaranteed, and the machining difficulty is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steam turbines, in particular to a centering intermediate steam seal with dehumidification function. BACKGROUND

[0002] Saturated steam has a great impact on the efficiency of steam turbines. Wet steam can cause a large amount of energy loss, including: energy loss caused by non-equilibrium condensation of supercooled saturated steam, braking loss caused by water droplets hitting the blades, steam flow accelerating water droplet loss during steam-water two-phase flow, and loss caused by water film deposition on solid surfaces, etc.

[0003] Wet steam in steam turbines is an important cause of efficiency decline and blade water erosion. The water droplets in wet steam are divided into extremely small water droplets (also known as primary water droplets) generated by spontaneous condensation and large water droplets (also known as secondary water droplets) from about 10 um to several hundred microns formed by the rupture of water film on the blade surface. Primary water droplets are more difficult to separate from the main flow because of their better following nature, and secondary water droplets are easier to separate.

[0004] Saturated steam has a great impact on the efficiency of steam turbines. Wet steam can cause a large amount of energy loss, including: energy loss caused by non-equilibrium condensation of supercooled saturated steam, braking loss caused by water droplets hitting the blades, steam flow accelerating water droplet loss during steam-water two-phase flow, and loss caused by water film deposition on solid surfaces, etc. At the same time, wet steam can also cause water erosion, impurity deposition and other hazards. Therefore, dehumidification of steam is very important for steam turbines. Currently, the mainstream dehumidification method is to add external dehumidification devices, and there are few internal dehumidification schemes for steam turbines. Generally, a dehumidification ring with a groove structure is used to prevent water droplet backflow and to discharge separated water droplets into a drain structure, thereby achieving internal dehumidification function of the steam turbine.

[0005] Taking the patent (application publication number CN117231316A) of Dongfang Steam Turbine Co., Ltd. as an example, a steam turbine dehumidification method is disclosed. The dehumidification system includes: a partition sleeve, a dehumidification guide plate, a partition, a suction hole and a suction slot. The gap between the partition sleeve, the dehumidification guide plate and the partition forms a suction chamber together. One end of the suction chamber is connected to the suction slot, and the other end is connected to the suction hole. The suction slot and the suction hole use the suction pressure difference to complete the suction of water droplets near the top of the blade and send them into the suction chamber. The suction slot is formed by the gap between the dehumidification guide plate and the partition. The suction hole is composed of through holes on the partition sleeve. The prior art sets a dehumidification structure between two-stage blades, which has a great impact on the through-flow efficiency and is not conducive to the arrangement of the blades. Moreover, the dehumidification structure does not have a centering function, which requires high product structure precision and is difficult to process. SUMMARY

[0006] To solve the above technical problems, the application provides a center-adjustable intermediate steam seal with a dehumidification function, which can not only realize a dehumidification effect, but also adjust the center position under the cooperation of an eccentric guide pin and an adjusting element, realize a center adjustment function of the intermediate steam seal, guarantee a radial gap and a dehumidification capacity, and reduce the processing difficulty.

[0007] The application adopts the following technical scheme: The center-adjustable intermediate steam seal with the dehumidification function comprises a steam turbine cylinder and a steam turbine rotor, the steam turbine cylinder is provided with a channel, and further comprises: an intermediate steam seal arranged between the steam turbine cylinder and the steam turbine rotor, which is provided with lugs on two sides and a guide pin hole in the front part; an eccentric guide pin which penetrates through the guide pin hole and is arranged on the channel, and comprises an eccentric pin and an eccentric sleeve matched with the eccentric pin; an adjusting element which is connected to the lug on one end and is located on the steam turbine cylinder on the other end, and comprises two spherical gaskets, two adjusting nuts and a screw, the screw is threadedly connected with at least one adjusting nut, and the adjusting nut is threadedly connected with the lug; and the spherical gasket is arranged at one end of the adjusting nut.

[0008] Preferably, the adjusting nut comprises an upper adjusting nut and a lower adjusting nut, the upper adjusting nut and the lower adjusting nut are both provided with an inner hexagonal adjusting hole, and the screw is threadedly connected with and locked by the upper adjusting nut and the lower adjusting nut.

[0009] Preferably, the end part of the upper adjusting nut and the lower adjusting nut is an arc-shaped structure matched with the spherical gasket, the lower adjusting nut is provided with a threaded part threadedly matched with the screw, and a gasket is arranged between the screw and the upper adjusting nut.

[0010] Preferably, the eccentric sleeve is provided with a mounting hole in the middle part, and the eccentric distance between the outer wall of the eccentric sleeve and the inner wall of the mounting hole is 1-3 mm.

[0011] Preferably, the circumferential surface of the eccentric sleeve is provided with an expansion groove, one end of the eccentric sleeve is provided with the eccentric pin, and the other end is provided with an adjusting bolt, and the adjusting bolt is threadedly matched with the eccentric pin.

[0012] Preferably, rotating the adjusting bolt can tightly press the eccentric sleeve on the eccentric pin to force the eccentric sleeve to expand and tightly adhere to the guide pin hole.

[0013] Preferably, the two ends of the eccentric pin are a conical end and a tenon-shaped end respectively, the conical end is matched with the tapered hole of the eccentric sleeve, and the tenon-shaped end is arranged on the channel.

[0014] Preferably, the steam turbine cylinder is provided with a limiting ring matched with the intermediate steam seal, and rotating the eccentric sleeve can drive the intermediate steam seal to translate around the axis of the eccentric pin.

[0015] As preferred, the intermediate steam seal comprises a steam seal body, a hydrophobic pipeline, a pressing plate and steam seal screws; the pressing plate is connected with the steam seal body by the steam seal screws to form a dehumidification chamber, the dehumidification chamber is provided with an annular water collecting groove, the water collecting groove is communicated with the bottom of the dehumidification chamber, and the bottom of the dehumidification chamber is provided with the hydrophobic pipeline.

[0016] As preferred, the pressing plate comprises an upper pressing plate and a lower pressing plate, the upper pressing plate and the lower pressing plate are provided with flow guiding parts for guiding liquid into the dehumidification chamber; the steam turbine rotor is provided with dehumidification blades, the dehumidification blades are provided with flow guiding walls, and when the steam turbine rotor rotates, the wet steam in the cylinder body enters the water collecting groove through the flow guiding walls on the dehumidification blades and is discharged by the hydrophobic pipeline.

[0017] Compared with the prior art, the intermediate steam seal has the following advantages: The intermediate steam seal of the present application adjusts the center position under the cooperation of the eccentric guide pin and the adjusting element, realizes the center adjusting function of the intermediate steam seal, guarantees the radial gap and the dehumidification capacity, and reduces the processing difficulty; under the action of the limiting ring, the rotation of the eccentric sleeve can drive the intermediate steam seal to translate around the axis of the eccentric pin to adjust the horizontal position of the intermediate steam seal; adjusting the length of the projecting lug of the adjusting nut can adjust the height position of the intermediate steam seal.

[0018] The present application integrates the dehumidification structure into the steam seal structure, utilizes the position which originally needs to be provided with a sealing structure (because some chambers of the steam turbine need to be provided with a steam extraction port, and the steam seal body is installed between the rotor and the cylinder to separate the two chambers and realize sealing), does not need to additionally arrange dehumidification components inside the chamber, avoids occupying the chamber space, is conducive to improving the utilization rate of the internal space of the steam turbine, optimizing the flow path and improving the flow efficiency, and is also more convenient for the reasonable arrangement of the blades. In addition, the steam seal body not only realizes the sealing function between different chambers of the steam turbine, but also realizes the dehumidification function. Through the flow guiding wall of the dehumidification blade, the wet steam can be effectively guided to the water collecting groove, the power generated by the rotation of the rotor and the steam flow characteristics are utilized, the dehumidification efficiency is improved, the water in the wet steam is discharged in time, the erosion of the water to the components such as the blades of the steam turbine is reduced, and the service life of the steam turbine is helped to be prolonged. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the center-adjustable intermediate steam seal.

[0020] Figure 2 It is an exploded structural schematic diagram of the center-adjustable intermediate steam seal.

[0021] Figure 3 It is a schematic diagram of the installation position of the eccentric sleeve.

[0022] Figure 4 It is a connection schematic diagram of the intermediate steam seal and the steam turbine rotor.

[0023] Figure 5 This is a schematic diagram of the eccentric guide pin structure.

[0024] Figure 6 This is a cross-sectional view of the eccentric guide pin.

[0025] Figure 7 This is a schematic diagram of the exploded structure of an eccentric guide pin.

[0026] Figure 8 A schematic diagram of the structure for adjusting the components.

[0027] Figure 9 A schematic diagram showing the connection between the component and the lug.

[0028] Figure 10 A schematic diagram of the exploded structure of the adjustment component.

[0029] In the diagram, the components are: turbine cylinder 1, channel 1-1, limit ring 1-2, turbine rotor 2, dehumidification blade 2-1, guide wall 2-2, intermediate steam seal 3, lug 3-1, guide pin hole 3-2, steam seal body 3-3, drain pipe 3-4, pressure plate 3-5, guide section 3-5-1, steam seal screw 3-6, eccentric guide pin 4, eccentric pin 4-1, conical end 4-1-1, tenon end 4-1-2, eccentric sleeve 4-2, mounting hole 4-2-1, expansion groove 4-2-2, adjusting bolt 4-3, adjusting element 5, spherical washer 5-1, adjusting nut 5-2, upper adjusting nut 5-2-1, lower adjusting nut 5-2-2, and screw 5-3. Detailed Implementation

[0030] To facilitate understanding of the technical solution of the present invention, the following detailed description is provided in conjunction with the accompanying drawings and specific embodiments.

[0031] Example 1 like Figures 1-3 As shown, an adjustable intermediate steam seal with dehumidification function includes a turbine cylinder 1, a turbine rotor 2, an intermediate steam seal 3, an eccentric guide pin 4, and an adjusting element 5. The intermediate steam seal 3 has a dehumidification structure, which can realize the dehumidification function. In addition, with the cooperation of the eccentric guide pin 4 and the adjusting element 5, the center position of the intermediate steam seal 3 can be adjusted to realize the center adjustment function of the intermediate steam seal 3, ensuring the radial clearance and dehumidification capacity, and reducing the processing difficulty.

[0032] Among them, the turbine cylinder 1 is provided with a channel 1-1; like Figure 4As shown, the intermediate steam seal 3 is located between the turbine cylinder 1 and the turbine rotor 2, with lugs 3-1 on both sides. The lugs 3-1 have a through threaded hole in the middle and a guide pin hole 3-2 at the front. It also includes a steam seal body 3-3, a drain pipe 3-4, a pressure plate 3-5, and a steam seal screw 3-6.

[0033] The pressure plate 3-5 is connected to the steam seal body 3-3 via the steam seal screw 3-6 to form a dehumidification chamber. The dehumidification chamber is provided with an annular water collection groove, which is connected to the bottom of the dehumidification chamber. The bottom of the dehumidification chamber is provided with a drainage pipe 3-4.

[0034] The pressure plate 3-5 includes an upper pressure plate and a lower pressure plate, both of which have guide sections 3-5-1 to guide liquid flow into the dehumidification chamber. The turbine rotor 2 is equipped with dehumidification blades 2-1, each with a guide wall 2-2. When the turbine rotor 2 rotates, the wet steam inside the cylinder enters the water collection groove through the guide walls 2-2 on several dehumidification blades 2-1 and is discharged through the drain pipe 3-4. When the wet steam passes near the dehumidification blades 2-1, it is biased towards the dehumidification chamber due to the action of the dehumidification blades 2-1. The disturbance caused by the dehumidification blades 2-1 causes some primary water droplets to condense into secondary water droplets with larger diameters and better tracking. After entering the dehumidification chamber, the secondary water droplets collect at the lower end of the dehumidification chamber. A drain pipe is provided at the lower end of the dehumidification chamber, and the collected water flows out along the drain pipe, thus achieving the dehumidification function.

[0035] like Figures 5-7 As shown, one end of the eccentric guide pin 4 passes through the guide pin hole 2-2 and is set on the channel 1-1. It includes an eccentric pin 4-1 and an eccentric sleeve 4-2 that cooperates with the eccentric pin 4-1. The eccentric sleeve 4-2 is provided with a tapered hole. The two ends of the eccentric pin 4-1 are a conical end 4-1-1 and a tenon end 4-1-2, respectively. The conical end 4-1-1 cooperates with the tapered hole of the eccentric sleeve 4-2, and the tenon end 4-1-2 is set on the channel 1-1 to realize the left and right limit of the eccentric pin 4-1 and prevent the eccentric pin 4-1 from moving left and right.

[0036] In addition, the eccentric sleeve 4-2 has a mounting hole 4-2-1 in the middle, and the eccentric distance between the outer wall of the eccentric sleeve 4-2 and the inner wall of the mounting hole is 1-3mm, preferably 1.5mm.

[0037] The eccentric sleeve 4-2 has an expansion groove 4-2-2 on its circumferential surface. One end of the eccentric sleeve 4-2 is provided with an eccentric pin 4-1, and the other end is provided with an adjusting bolt 4-3. The adjusting bolt 4-3 is threadedly engaged with the eccentric pin 4-1. Rotating the adjusting bolt 4-3 can press the eccentric sleeve 4-2 tightly against the eccentric pin 4-1, forcing the eccentric sleeve 4-2 to expand and fit tightly against the guide pin hole 3-2.

[0038] The turbine cylinder is provided with a limiting ring 1-2 cooperating with the intermediate steam seal 3, and the rotating eccentric sleeve 4-2 can drive the intermediate steam seal 3 to translate around the axis of the eccentric pin 4-1. The eccentric sleeve 4-2 can rotate relative to the conical end 4-1-1 of the eccentric pin 4-1. In use, rotating the eccentric sleeve 4-2 can push the intermediate steam seal 3 to move through the outer wall of the eccentric sleeve 4-2. Since the intermediate steam seal 3 cooperates with the limiting ring 1-2, the intermediate steam seal 3 can only translate around the axis of the eccentric pin 4-1, so that the intermediate steam seal 3 can be adjusted in the horizontal direction.

[0039] As shown in Figures 8-10 The adjusting element 5 is connected to the lug 3-1 at one end and is located on the turbine cylinder 1 at the other end for adjusting the height of the intermediate steam seal 3. In this embodiment, two adjusting elements 5 are provided, one on each side. The adjusting element 5 includes two spherical washers 5-1, two adjusting nuts 5-2, and a screw 5-3. The two adjusting nuts 5-2 are an upper adjusting nut 5-2-1 and a lower adjusting nut 5-2-2. The outer surfaces of the upper adjusting nut 5-2-1 and the lower adjusting nut 5-2-2 are provided with threads, and both are provided with an internal hexagonal adjusting hole. The position of the upper adjusting nut 5-2-1 and the lower adjusting nut 5-2-2 on the lug 3-1 can be adjusted through the internal hexagonal adjusting hole. The screw 5-3 is threadedly connected to the upper adjusting nut 5-2-1 and the lower adjusting nut 5-2-2 and locks the upper adjusting nut 5-2-1 and the lower adjusting nut 5-2-2.

[0040] In installation, the lower adjusting nut 5-2-2 is first threadedly connected to the lower end of the lug 3-1. After adjusting the length of the lower adjusting nut 5-2-2 extending out, the upper adjusting nut 5-2-1 is arranged at the upper end of the lug 3-1. Then the screw 5-3 is connected to the upper adjusting nut 5-2-1 and the lower adjusting nut 5-2-2 in sequence and is tightened. The lower adjusting nut 5-2-2 is provided with a threaded portion threadedly cooperating with the screw 5-3. The screw 5-3 threadedly cooperates with the upper adjusting nut 5-2-1 and the lower adjusting nut 5-2-2. The height of the intermediate steam seal 3 can be adjusted by adjusting the length of the lower adjusting nut 5-2-2 extending out of the lug 3-1.

[0041] The end portions of the upper adjusting nut 5-2-1 and the lower adjusting nut 5-2-2 are arc-shaped structures fitting the spherical washers 5-1. The spherical washers 5-1 are arranged at one end of the upper adjusting nut 5-2-1 and the lower adjusting nut 5-2-2.

[0042] In this embodiment, a washer is arranged between the screw 5-3 and the upper adjusting nut 5-2-1 to prevent the head of the screw 5-3 from damaging the upper adjusting nut 5-2-1.

[0043] The above merely is the preferred embodiment of the present application, the protection scope of the present application is limited by the scope defined by the claims, and several improvements and refinements made by the person skilled in the art without departing from the spirit and scope of the present application should also be regarded as the protection scope of the present application.

Claims

1. A self-aligning intermediate steam seal with dehumidification function, comprising a turbine cylinder (1) and a turbine rotor (2); characterized in that, The turbine cylinder block is provided with a channel (1-1), and also includes: The intermediate steam seal (3) is located between the turbine cylinder (1) and the turbine rotor (2), with lugs (3-1) on both sides and guide pin holes (3-2) at the front. An eccentric guide pin (4) has one end that passes through a guide pin hole (2-2) and is set on a channel (1-1), including an eccentric pin (4-1) and an eccentric sleeve (4-2) that cooperates with the eccentric pin (4-1). The adjusting element (5) is connected at one end to the lug (3-1) and at the other end to the turbine cylinder (1). It includes two spherical washers (5-1), two adjusting nuts (5-2) and a screw (5-3). The screw (5-3) is threaded to at least one adjusting nut (5-2), and the adjusting nut (5-2) is threaded to the lug (3-1). The spherical washers (5-1) are located at one end of the adjusting nuts (5-2).

2. The self-aligning intermediate steam seal with dehumidification function according to claim 1, characterized in that, The adjusting nut (5-2) includes an upper adjusting nut (5-2-1) and a lower adjusting nut (5-2-2). Both the upper adjusting nut (5-2-1) and the lower adjusting nut (5-2-2) are provided with internal hexagonal adjustment holes. The screw (5-3) passes through the upper adjusting nut (5-2-1) and is threadedly connected to and locked to the lower adjusting nut (5-2-2).

3. The self-aligning intermediate steam seal with dehumidification function according to claim 2, characterized in that, The ends of the upper adjusting nut (5-2-1) and the lower adjusting nut (5-2-2) are arc-shaped structures that fit the spherical washer (5-1); the lower adjusting nut (5-2-2) is provided with a threaded part that mates with the screw (5-3); a washer is provided between the screw (5-3) and the upper adjusting nut (5-2-1).

4. The self-aligning intermediate steam seal with dehumidification function according to claim 1, characterized in that, The eccentric sleeve (4-2) has a mounting hole (4-2-1) in the middle, and the eccentric distance between the outer wall of the eccentric sleeve (4-2) and the inner wall of the mounting hole is 1-3mm.

5. The self-aligning intermediate steam seal with dehumidification function according to claim 1, characterized in that, The eccentric sleeve (4-2) has an expansion groove (4-2-2) on its circumferential surface. One end of the eccentric sleeve (4-2) is provided with an eccentric pin (4-1), and the other end is provided with an adjusting bolt (4-3). The adjusting bolt (4-3) is threadedly engaged with the eccentric pin (4-1).

6. The self-aligning intermediate steam seal with dehumidification function according to claim 5, characterized in that, Rotating the adjusting bolt (4-3) can press the eccentric sleeve (4-2) tightly against the eccentric pin (4-1), forcing the eccentric sleeve (4-2) to expand and fit tightly against the guide pin hole (3-2).

7. The self-aligning intermediate steam seal with dehumidification function according to claim 5, characterized in that, The two ends of the eccentric pin (4-1) are a conical end (4-1-1) and a tenon end (4-1-2); the conical end (4-1-1) is engaged with the conical hole of the eccentric sleeve (4-2), and the tenon end (4-1-2) is set on the channel (1-1).

8. The self-aligning intermediate steam seal with dehumidification function according to claim 5, characterized in that, The turbine cylinder is equipped with a limiting ring (1-2) that cooperates with the intermediate steam seal (3). Rotating the eccentric sleeve (4-2) can drive the intermediate steam seal (3) to translate around the axis of the eccentric pin (4-1).

9. The self-aligning intermediate steam seal with dehumidification function according to claim 1, characterized in that, The intermediate steam seal (3) includes a steam seal body (3-3), a condensate drain pipe (3-4), a pressure plate (3-5), and a steam seal screw (3-6). The pressure plate (3-5) and the steam seal body (3-3) are connected by the steam seal screw (3-6) to form a dehumidification chamber. The dehumidification chamber is provided with an annular water-collecting groove, which is connected to the bottom of the dehumidification chamber. The bottom of the dehumidification chamber is provided with a condensate drain pipe (3-4).

10. The self-aligning intermediate steam seal with dehumidification function according to claim 9, characterized in that, The pressure plate (3-5) includes an upper pressure plate and a lower pressure plate. The upper pressure plate and the lower pressure plate have a guide section (3-5-1) for guiding liquid to the dehumidification chamber. The turbine rotor (2) is provided with dehumidification blades (2-1). The dehumidification blades (2-1) have guide walls (2-2). When the turbine rotor (2) rotates, the wet steam inside the cylinder enters the water collection groove through the guide walls (2-2) on several dehumidification blades (2-1) and is discharged through the drainage pipe (3-4).

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