Apparatus for adjusting clearance and gas turbine including the same

Patent metadata

Field	Value
Publication number	US-2021040862-A1
Application number	US-202016895220-A
Country	US
Kind code	A1
Filing date	Jun 8, 2020
Priority date	Aug 8, 2019
Publication date	Feb 11, 2021
Grant date	—

Abstract

A clearance adjusting apparatus to move a thrust bearing of a gas turbine back and forth to adjust a tip clearance of a turbine is provided. The clearance adjusting apparatus includes an adjusting plate disposed to move forward from or rearward to a reference surface, a biasing cylinder disposed to selectively move the adjusting plate back and forth, a stopper disposed to be moved toward the adjusting plate after being moved forward to prevent a rearward movement of the adjusting plate, a position sensor disposed to measure a distance from the reference surface to the adjusting plate, and a controller configured to receive information about measurements from the position sensor and control an operation of the stopper and the biasing cylinder based on the received information.

First claim

What is claimed is:

1 . A clearance adjusting apparatus to move a thrust bearing of a gas turbine back and forth to adjust a tip clearance of a turbine, the clearance adjusting apparatus comprising:
an adjusting plate disposed on the thrust bearing to move forward from or rearward to a reference surface; a biasing cylinder disposed on a rear side of the adjusting plate to selectively move the adjusting plate back and forth; a stopper disposed adjacent to the adjusting plate to be moved toward the adjusting plate after being moved forward to prevent a rearward movement of the adjusting plate; a position sensor disposed on the biasing cylinder to measure a distance from the reference surface to a rear surface of the adjusting plate; and a controller configured to receive information about measurements from the position sensor and control an operation of the stopper and the biasing cylinder based on the received information.

2 . The clearance adjusting apparatus according to claim 1 , wherein the biasing cylinder comprises:
a housing; a division part disposed inside the housing to reciprocate back and forth such that the division part is arranged to divide an interior space of the housing into a front space and a rear space; and a biasing part connected between a front side of the division part and a rear surface of the adjusting plate to move the adjusting plate back and forth.

3 . The clearance adjusting apparatus according to claim 2 , wherein the position sensor is disposed in front of the housing.

4 . The clearance adjusting apparatus according to claim 3 , wherein the biasing cylinder further comprises a front supply part and a rear supply part through which a fluid flows into and out of the front space and the rear space, respectively, and
the controller is configured to supply a fluid to the rear space through the rear supply part if the division part is to be moved forward and to supply a fluid to the front space through the front supply part if the division part is to be moved rearward.

5 . The clearance adjusting apparatus according to claim 1 , wherein the stopper is disposed under the adjusting plate such that a rear surface thereof is placed on the reference surface, the stopper having a front stepped surface on which a plurality of step faces are formed at different distances from the reference surface, and
the controller is configured to seat the adjusting plate on a target step face by moving the adjusting plate forward, raising the stopper, and moving the adjusting plate rearward.

6 . The clearance adjusting apparatus according to claim 5 , wherein the stopper is configured such that an underlying step face protrudes more forward from an overlying step face thereof, and
the controller is configured to select, from the step faces of the stopper, a step face having a distance from the reference surface corresponding to a target displacement of the adjusting plate from the reference surface, and seat the adjusting plate on the selected step face.

7 . The clearance adjusting apparatus according to claim 6 , wherein the controller is configured to stop the forward movement of the adjusting plate and raise the stopper if a distance from the reference surface to the rear surface of the adjusting plate is greater than a distance from the reference surface to the selected step face and is smaller than a distance from the reference surface to the step face disposed below the selected step face.

8 . The clearance adjusting apparatus according to claim 7 , wherein the controller is configured to raise the stopper such that an upper surface of the step face below the selected step face becomes flush with a lower surface of the adjusting plate, and move the adjusting plate rearward so that the adjusting plate is seated on the selected step face.

9 . The clearance adjusting apparatus according to claim 5 , further comprising a fastening member disposed under the adjusting plate and having a stepped surface with a plurality of step contact faces to be selectively brought into contact with the plurality of step faces of the stopper, respectively.

10 . The clearance adjusting apparatus according to claim 9 , further comprising a fastening bolt to fasten the fastening member and the adjusting plate together through the adjusting plate.

11 . A gas turbine comprising:
a compressor including a compressor stator into which air is externally introduced and a compressor rotor disposed in the compressor stator to compress the air; a combustor configured to mix the compressed air with fuel and combust the air and fuel mixture; a turbine including a turbine stator through which the combustion gas supplied from the combustor flows and a turbine rotor disposed in the turbine stator to rotate with the combustion gas flowing therethrough; a shaft disposed in front of the compressor rotor; a thrust bearing disposed around an outer circumferential surface of the shaft; and a clearance adjusting apparatus disposed on the thrust bearing to move the thrust bearing back and forth so that the shaft, the compressor rotor, and the turbine rotor are moved back and forth, wherein the clearance adjusting apparatus comprises:
an adjusting plate disposed on the thrust bearing to move forward from or rearward to a reference surface;
a biasing cylinder disposed on a rear side of the adjusting plate to selectively move the adjusting plate back and forth;
a stopper disposed adjacent to the adjusting plate to be moved toward the adjusting plate after being moved forward to prevent a rearward movement of the adjusting plate;
a position sensor disposed on the biasing cylinder to measure a distance from the reference surface to a rear surface of the adjusting plate; and
a controller configured to receive information about measurements from the position sensor and control an operation of the stopper and the biasing cylinder based on the received information.

12 . The gas turbine according to claim 11 , wherein the biasing cylinder comprises:
a housing; a division part disposed inside the housing to reciprocate back and forth such that the division part is arranged to divide an interior space of the housing into a front space and a rear space; and a biasing part connected between a front side of the division part and a rear surface of the adjusting plate to move the adjusting plate back and forth.

13 . The gas turbine according to claim 12 , wherein the position sensor is disposed in front of the housing.

14 . The gas turbine according to claim 13 , wherein the biasing cylinder further comprises a front supply part and a rear supply part through which a fluid flows into and out of the front space and the rear space, respectively, and
the controller is configured to supply a fluid to the rear space through the rear supply part if the division part is to be moved forward and to supply a fluid to the front space through the front supply part if the division part is to be moved rearward.

15 . The gas turbine according to claim 11 , wherein the stopper is disposed under the adjusting plate such that a rear surface thereof is placed on the reference surface, the stopper having a front stepped surface on which a plurality of step faces are formed at different distances from the reference surface, and
the controller is configured to seat the adjusting plate on a target step face by moving the adjusting plate forward, raising the stopper, and moving the adjusting plate rearward.

16 . The gas turbine according to claim 15 , wherein the stopper is configured such that an underlying s

Assignees

• Doosan Heavy Ind & Construction Co Ltd

Inventors

• Kim Yeong Chun

Classifications

• F01D25/168

  for axial load mainly · CPC title

• F01D11/14 Primary

  Adjusting or regulating tip-clearance, i.e. distance between rotor-blade tips and stator casing (rotors with blades adjustable in operation F01D7/00) · CPC title

• F05D2220/32

  in gas turbines · CPC title

• F01D25/16

  Arrangement of bearings; Supporting or mounting bearings in casings (bearings per se F16C) · CPC title

• F02C3/05

  the compressor and the turbine being of the radial flow type · CPC title