Measuring a turbine vane airfoil leading edge thickness 1

[wohorhor]

Are there any standard measuring gage out there to measure the leading edge thickness of an airfoil on a turbine vane?

Aside from fabricating one from scratch, i am hoping there is such a gage out in the market.

 

[plasgears]

Measure the thickness at one or more offsets from the LE. QA would help design the tools.

 

[berkshire]

wohorhor
Would something like this work for you?

http://www.fvfowler.com/pdf/2304/2304_506.pdf

I use a device like this to get leading edge contours off wings.
B.E.

 

[leeconner]

Obvious first choice is the tool the mfgr's manual requires, typicall including any fixture necessary to establish measurement criteria. Absent this, the next choice would be an optical comparator. If you are talking 15 or 16th stage vanes, these tools would be critical for such small sizes. For larger vanes, a simple fixture to immobilize the vane in a horizontal plane, installed on a surface plate, could then be approached with a height gauge. Measurements taken at the same chord and span stations above and below the leading edge would result in accurate vane LE thickness. The mfgr's table of limits would establish the appropriate chord and span stations to bemeasured to pass/fail a vane.

 

[yates]

Not quite sure what you're looking for, the actual leading edge radius or the throat passage on the shoulder behind the leading edge. Since you're talking about Turbine vanes (and not compressor blades) the smallest cross-sectional area of gas flow (throat) is paramount to achieving required performance. We used to do this once the vanes were finally mounted with a GO/NOGO disc-shaped gage. You may want to do this on individual vanes before assembly, and the only way to do this is with a guillotine gage, with the profile tolerance built-in, at different section heights.

 

[berkshire]

wohorhor
This article addresses, what, I think is your problem.

http://www.qualitydigest.com/sep99/html/brownsharpe.html

See if this helps you.
B.E.