Separation measurement method and separation measurement device

Patent metadata

Field	Value
Publication number	US-9714823-B2
Application number	US-201514737684-A
Country	US
Kind code	B2
Filing date	Jun 12, 2015
Priority date	Jun 27, 2014
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

A method for measuring a separation (a) between blade tips of rotor blades ( 40 ) on a rotor and a casing ( 41 ) annularly surrounding the rotor blade tips, when the rotor is rotating: measuring separation using at least one separation measurement device ( 1 ) which measures in contactless fashion. A separation measurement device for carrying this method includes a tubular housing ( 2 ), a separation sensor which measures in contactless fashion and which is accommodated in the housing ( 2 ) such that the sensor moves axially between an operating position, wherein a tip of the sensor projects outward from the separation measurement device ( 1 ), and a withdrawn position, wherein the tip of the separation sensor ( 7 ) is arranged within the separation measurement device ( 1 ); and an arresting device ( 8 ) which arrests the separation sensor ( 7 ) at least in its operating position.

First claim

The invention claimed is:

1. A method for measuring a separation between blade tips of rotor blades on a rotor and a casing annularly surrounding the rotor blade tips, and separated radially outward from the rotor blade tips when the rotor is rotating;
the method comprising:
measuring the separation in contactless fashion using at least one separation measurement device which measures in contactless fashion, the separation measurement device including a cylinder and an arresting device;
arresting movement of the cylinder in at least one position by moving a part of the arresting device toward the cylinder so that the part of the arresting device contacts the cylinder; and
releasing the cylinder from an arrested position by moving the part of the arresting device away from the cylinder so that the part of the arresting device does not contact the cylinder.

2. The method as claimed in claim 1 wherein:
the separation measurement device further includes a confocal chromatic separation sensor or an acoustic separation sensor.

3. The method as claimed in claim 1 , further comprising:
inserting the separation measurement device into a through bore which extends radially through the casing and is accessible from outside for carrying out the separation measurement.

4. The method as claimed in claim 3 , wherein:
the separation measurement device and the through bore are formed such that, in a normal state, the casing extends radially further inward than the separation measurement device accommodated in the through bore.

5. The method as claimed in claim 1 , further comprising:
performing the separation measurement at a plurality of circumferential positions around the casing.

6. The method as claimed in claim 5 , wherein the circumferential positions are evenly spaced apart from one another.

7. A separation measurement device for performing a method as claimed in claim 1 , comprising:
a tubular housing; and
a separation sensor configured to measure in contactless fashion and which is accommodated in the housing at a location and in a manner such that the sensor is movable axially along an axis of the sensor between an operating position, wherein a tip of the separation sensor projects outward from the separation measurement device, and a withdrawn position, wherein the tip of the separation sensor is within the separation measurement device;
wherein the arresting device is configured such that the separation sensor can be arrested or held at least in its operating position.

8. The separation measurement device as claimed in claim 7 , wherein the separation sensor is a confocal chromatic separation sensor or an acoustic separation sensor.

9. The separation measurement device as claimed in claim 7 , further comprising:
at least one spring arranged and configured such that its spring force opposes movement of the separation sensor from its withdrawn position into its operating position.

10. The separation measurement device as claimed in claim 7 , wherein:
the cylinder is accommodated in a longitudinally movable fashion in the housing and the separation sensor is arranged in the cylinder.

11. The separation measurement device as claimed in claim 10 ,
wherein the separation sensor has a rod-shape; and
an axial blind bore is provided at the free end of the cylinder in which the rod shaped sensor is arranged.

Assignees

• Siemens Ag

Inventors

• MüLLER ANDREAS
• Polesky Peter
• Tritsch Katrin
• Woitscheck Rolf-Dieter

Classifications

• G01B11/14 Primary

  for measuring distance or clearance between spaced objects or spaced apertures (G01B11/26 takes precedence; rangefinders G01C3/00) · CPC title

• F01D21/003

  Arrangements for testing or measuring (for measuring vibrations G01H) · CPC title

• G01B17/00

  Measuring arrangements characterised by the use of infrasonic, sonic or ultrasonic vibrations · CPC title

• F01D11/14

  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

• G01B21/16 Primary

  for measuring distance of clearance between spaced objects · CPC title