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107.3 Non-Contact Clearance Measurement Systems for Use in Gas Turbines


The purpose is to develop a standard for gas turbine instrumentation used in the measurement of blade tip to engine casing clearance during engine running.


This specification provides guidance on the standardization of the specification and qualification testing of high bandwidth, non-contact clearance measurement systems for use in gas turbines to measure blade tip clearances at high temperatures.

The specification makes some references to the capacitive based technology. However, many parameters are generic. Future updates of this specification will include details to the other emerging technologies like optical and radar (micro-wave).

The object of the specification is to provide a common language and agreed methods for testing different systems to the same standard.