National Physical Laboratory

Measurement of safety critical components

NPL's extensive turbine blade measurement expertise helps customer improve safety and drive down costs.

Measurement of safety critical components

A customer from the aerospace sector approached NPL Huddersfield to measure their high value machined turbine blades. NPL measured in-use wear of the components, helping the customer to trouble shoot any potential safety issues.

The challenge

Turbine blades used in aerospace engines are very complex, freeform, high value components that are very challenging to measure to first principles. Yet the measurement tolerances for them are very tight due to the obvious safety issues that can arise if a part is out of tolerance (i.e. in-use engine failure).

The solution

NPL staff with between them over nine decades of experience of measuring turbine blades performed first principles and coordinate measuring machine (CMM) measurements of the turbine blades.

This included measurements of a range of blade features/surfaces such as: dovetails, fir trees, cooling holes, throat area, blade height, leading edge, and trailing edge.

We also provided measurements of in-use wear of the component, and correlated these with measurements taken by the customer's in-house metrologists. This comparison allowed trouble-shooting of safety critical issues.

The impact

The impact of NPL's measurements of these components cannot be overstated.

We were able to confirm the 'form, fit, and function' of these safety critical components, which avoids out of tolerance components being used in engines that could then fail in-use.

Improved measurements of these components, which each cost £1,000s, also reduces the very costly scrap that can result from poor measurement.


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Last Updated: 16 Oct 2014
Created: 22 Dec 2010


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