CN110552745A

CN110552745A - Steam turbine thrust pad assembly and method for prolonging service life of thrust pad

Info

Publication number: CN110552745A
Application number: CN201910897230.5A
Authority: CN
Inventors: 王跃文; 蒋鹏仪
Original assignee: Copper Industry Branch Of Yunnan Tin Co Ltd
Current assignee: Copper Industry Branch Of Yunnan Tin Co Ltd
Priority date: 2019-09-23
Filing date: 2019-09-23
Publication date: 2019-12-10

Abstract

a thrust tile component of a steam turbine and a method for prolonging the service life of the thrust tile are provided, the thrust tile component of the steam turbine is characterized in that thrust tiles (3) are sequentially arranged on two end faces of a tile seat formed by an upper tile seat (1-1) and a lower tile seat (1-2) in an involution mode, tile seat oil return holes (1-3) are uniformly distributed on the tile seat, an upper half gasket (2-1) and a lower half gasket (2-2) are respectively padded on the two end faces of the upper tile seat and the lower tile seat, gasket oil return holes (2-3) corresponding to the tile seat oil return holes (1-3) are respectively processed on the upper half gasket and the lower half gasket, the thrust tiles are sequentially arranged on the outer sides of the upper half gasket and the lower half gasket, and the edge of the outer side of a front thrust face of each thrust tile in the rotation direction of a. The invention can effectively reduce the abrasion of the thrust pad and prolong the service life of the thrust pad.

Description

Steam turbine thrust pad assembly and method for prolonging service life of thrust pad

Technical Field

The invention relates to the technical field of a thrust pad of a steam turbine.

Background

The turbine thrust pad is a part of a turbine bearing and is a key part necessary for ensuring the axial positioning of a turbine rotor. Usually, a pair of shoe seats is provided with a thrust shoe and a supporting thrust shoe, and the thrust shoe and the supporting thrust shoe bear the thrust from the axial direction of the turbine rotor and the radial gravity when the unit operates. In the running process of the unit, the thrust pad is not in direct contact with the rotor, and the pressurized lubricating oil enters a gap between the turbine rotor and the thrust pad to form an oil film, so that the lubricating and cooling effects are achieved. With the unit operating. The working surface of the thrust shoe is gradually worn. The oil film clearance increases. The damage to a secondary turbine bearing is typically caused by wear and tear of the thrust pads.

Disclosure of Invention

the invention aims to provide a simple and practical steam turbine thrust shoe assembly with prolonged service life and a method for prolonging the service life of the steam turbine thrust shoe.

the technical scheme adopted by the invention is as follows:

The utility model provides a thrust tile subassembly of steam turbine, installs the thrust tile in proper order by last tile seat and lower tile seat to closing the tile seat both ends face of constituteing, and the equipartition has the tile seat oil gallery on the tile seat, and last tile seat and lower tile seat both ends face have filled up first packing ring and second packing ring respectively, process the packing ring oil gallery that corresponds the tile seat oil gallery on first packing ring and second packing ring respectively, the thrust tile is installed in proper order in first packing ring and second packing ring outside, and the arris processing in the preceding push surface outside of every thrust tile along rotor rotation direction is the inclined plane. The chamfer angle is 30 degrees.

The method for prolonging the service life of the turbine thrust pad by adopting the turbine thrust pad assembly provided by the invention comprises the following steps of:

a. The thrust pads are detached from the upper pad holder and the lower pad holder, and the outer side edge of the front push surface of each thrust pad along the rotation direction of the rotor is processed into an inclined surface;

b. measuring the sizes of the upper pad holder and the lower pad holder of the thrust pad, and processing an upper half gasket and a lower half gasket with different thicknesses according to the measurement result;

c. Measuring the gap between the thrust pad and the rotor, and selecting an upper half gasket and a lower half gasket which are matched according to the size of the measured gap;

d. Respectively assembling the selected upper half gasket and the selected lower half gasket in the upper tile seat and the lower tile seat, and aligning an oil return hole of the gasket with an oil return hole of the tile seat;

e. The thrust pads are sequentially assembled outside the half-washers and the lower half-washer and positioned inside the upper pad holder and the lower pad holder.

according to the invention, the gasket is arranged between the tile seat and the thrust tile, so that the thickness of an oil film formed between a gap between a turbine rotor and the adjacent thrust tile is kept in an optimal range of 30-80 um in the running process of the turbine unit. The inclined surface is processed on the thrust pad, so that lubricating oil can smoothly flow into a space between the thrust pad and the working surface to form an oil film under the action of viscous force when the unit runs, the direct contact between the thrust pad and the rotor is avoided, the abrasion of the thrust pad is reduced, and the service life of the thrust pad is prolonged.

the invention may provide a set of gasket alternatives of different thicknesses. In the operation process of the unit, the tile surface is gradually abraded, and the washers can be increased or decreased at any time after the oil film clearance is increased, so that the clearance is adjusted, overlarge or undersize of the clearance is avoided, and the optimal oil film thickness is ensured.

drawings

FIG. 1 is an exploded view of a steam turbine thrust shoe assembly according to the present invention;

FIG. 2 is a schematic structural view of a single thrust shoe;

FIG. 3 is a schematic view of a steam turbine thrust shoe assembly of the present invention mounted to a steam turbine rotor.

Detailed Description

As shown in figures 1, 2 and 3, the thrust shoe assembly of the steam turbine is characterized in that thrust shoes 3 are sequentially arranged on two end faces of a shoe seat formed by combining an upper shoe seat 1-1 and a lower shoe seat 1-2, shoe seat oil return holes 1-3 are uniformly distributed on the shoe seat, an upper half gasket 2-1 and a lower half gasket 2-2 are respectively padded on the two end faces of the upper shoe seat and the lower shoe seat, gasket oil return holes 2-3 corresponding to the shoe seat oil return holes 1-3 are respectively machined on the upper half gasket and the lower half gasket, the thrust shoes are sequentially arranged on the outer sides of the upper half gasket and the lower half gasket, the outer side edge of a front thrust face of each thrust shoe along the rotation direction of a rotor is machined into an inclined plane 3-1, the chamfer angle of the inclined plane 3-1 is preferably 30 degrees, and the machining depth is 2 mm.

As shown in fig. 3, a support shoe 5 and a shoe seat combined by an upper shoe seat 1-1 and a lower shoe seat 1-2 are sequentially sleeved outside a turbine rotor 4, an upper half washer 2-1 and a lower half washer 2-2 are respectively assembled in the upper shoe seat and the lower shoe seat, and a thrust shoe 3 is sequentially arranged in the upper shoe seat and the lower shoe seat outside the upper half washer 2-1 and the lower half washer 2-2.

The method for prolonging the service life of the turbine thrust pad by adopting the turbine thrust pad assembly shown in the figures 1 and 2 is carried out according to the following steps by referring to figure 3:

a. the thrust pads 3 are detached from the upper pad seats 1-1 and the lower pad seats 1-2, and the outer side edge of the front push surface of each thrust pad along the rotation direction of the rotor is processed into an inclined surface 1-3;

b. Measuring the sizes of an upper pad seat and a lower pad seat of the thrust pad, and processing an upper half gasket 2-1 and a lower half gasket 2-2 with different thicknesses according to the measurement result;

c. Measuring the gap between the thrust pad and the rotor 4, and selecting an upper half washer and a lower half washer which are matched according to the measured gap size;

d. Assembling the selected upper half gasket 2-1 and the selected lower half gasket 2-2 in the upper tile seat and the lower tile seat respectively, and aligning the gasket oil return hole 2-3 with the tile seat oil return hole 1-3;

e. the thrust pads 3 are fitted in sequence outside the half-washers and the lower half-washer and inside the upper and lower pad holders.

The method can add the gasket between the original shoe seat and the thrust shoe of the steam turbine rotor to adjust the gap of the thrust shoe, the thickness of the gasket can be set to be a series of thicknesses of 100um, 50um, 20um and 10um, and the thickness of an oil film formed between the steam turbine rotor and the gap between the adjacent thrust shoe can be always kept in the optimal range of 30-80 um in the running process of the steam turbine set by flexibly adjusting the increase and decrease of the gasket. In the running process of the steam turbine unit, the tile surface is gradually abraded, and the gaskets can be increased and decreased at any time after the oil film clearance is increased, so that the clearance is adjusted, overlarge or undersize of the clearance is avoided, and the optimal oil film thickness is ensured. The processed inclined surface 1-3 is beneficial to lubricating oil to smoothly flow into a space between the thrust pad and the working surface to form an oil film under the action of viscous force when the unit runs.

Claims

1. A thrust tile assembly of a steam turbine is characterized in that thrust tiles (3) are sequentially mounted on two end faces of a tile seat formed by an upper tile seat (1-1) and a lower tile seat (1-2) in an involution mode, tile seat oil return holes (1-3) are uniformly distributed on the tile seat, an upper half gasket (2-1) and a lower half gasket (2-2) are respectively padded on the two end faces of the upper tile seat and the lower tile seat, gasket oil return holes (2-3) corresponding to the tile seat oil return holes (1-3) are respectively machined in the upper half gasket and the lower half gasket, the thrust tiles are sequentially mounted on the outer sides of the upper half gasket and the lower half gasket, and an edge of the outer side of a front pushing face of each thrust tile in the rotation direction of a rotor is machined into an inclined plane (3-1).

2. the thrust shoe assembly of the steam turbine as claimed in claim 1, wherein said chamfer (3-1) machined on the thrust shoe is chamfered at 30 °.

3. a method of extending the useful life of a turbine thrust shoe using the turbine thrust shoe assembly of claim 1 or 2, comprising the steps of:

a. the thrust pads (3) are detached from the upper pad holder (1-1) and the lower pad holder (1-2), and the outer side edge of the front push surface of each thrust pad along the rotation direction of the rotor is processed into an inclined surface (1-3);

b. measuring the sizes of an upper pad seat and a lower pad seat of the thrust pad, and processing an upper half gasket (2-1) and a lower half gasket (2-2) with different thicknesses according to the measurement result;

c. Measuring the gap between the thrust pad and the rotor (4), and selecting an upper half washer and a lower half washer which are matched according to the measured gap size;

d. Assembling the selected upper half gasket (2-1) and the lower half gasket (2-2) in the upper tile seat and the lower tile seat respectively, and aligning the gasket oil return hole (2-3) with the tile seat oil return hole (1-3);

e. and the thrust pads (3) are sequentially assembled on the outer sides of the half gaskets and the lower half gaskets and positioned in the upper pad holder and the lower pad holder.