High Temperature Instrumentation and Strain Gauging
The optimisation of aerothermal performance requires an understanding of the stress, strain and vibration imposed on gas turbine blades, vanes, discs, casings and fabrications. Rotadata have developed special techniques and procedures to apply high temperature sensors and wiring onto static, rotating and reciprocating components. The instrumentation can be designed to operate at temperatures in excess of 1,000°C and at rotational speeds up to 130,000 revolutions per minute.
Fig. 1: High temperature ceramically coated strain gauge attached to an airfoil blade tip showing final water ingress protective coating applied prior to despatch. Protective coating burns off during first engine run.
Rotadata Limited has over 25 years of experience in the application, onto rotating, reciprocating and stator parts, of a variety of sensors such as thermocouples, strain gauges, accelerometers, pressure transducers and their lead out wiring, for a whole range of pressure, temperature, environmental and high speed components located in aero engines, gas turbines, development and test rigs, wind tunnel models, automobile and marine engines, compressors and turbo chargers.
In recent years it has become possible to extend the measurement range and operation of strain gauge and thermocouple sensors and their associated lead out wires wiring to cover the attachment of the sensors and their lead out wiring onto turbine and impeller blades and vanes operating at temperatures in excess of 1,000°C and/or rotational speeds up to 130,000 revolutions per minute. At these high temperatures and speeds, the life expectancy of the sensors and their lead out wires and terminals can be short but with innovative designs produced by our engineers, life expectancy is gradually being extended.
Our skilled technicians work closely with Rotadata customers to ensure all aspects of the strain gauge and thermocouple installation, including correct placement and orientation. Equally important is the planning of the routing of the sensor lead out wiring over the component or part being instrumented, to prevent or minimise damage of failure due to factors like centrifugal forces. Finally the lead out of the sensor wiring is checked to avoid failure away from the component. We are specialised in the design and application of sensors for many industries including sensor attachment to fixed, reciprocating, rotating engines and parts with the most stringent of aero-space standards being provided as routine.
We have successfully attached sensors to engine parts in the most harsh of environments including automobile engine cylinder heads, high speed turbochargers, rocket and missile components, power, industrial and aero engine gas turbines and combustors, railway carriage and locomotive stock, hydro power generators and a variety of heaters and coolers used in the power generation and petro-chemical industries.
