Some information on Dye Penetrant testing:
Dye penetrant testing can theoretically been done on any metal or alloy,
both ferrous and non-ferrous. It has the great advantage over Magnaflux
testing that you don't need any tools - you can even dye penetrant test
objects in situ, as long as you can thouroughly clean them.
As stated by another lister, a set comprises of three spray cans:
Penetrant Red, Penetrant Cleaner and Penetrant Developer. After cleaning
the object as good as possible, Penetrant Red is sprayed on the surface
to be inspected. The stuff has creeping properties: it tends to creep
into cracks (hence the need to clean first). Allow 10 to 20 mins for
proper penetration, then apply Cleaner which will remove the surplus red
material from the surface but should leave the Penetrant Red in the
cracks. Wipe clean and spray the Developer which is a white, strong
absorbent drying rapidly to powder. This will pull the Penetrant Red out
of the cracks and if there are any cracks they will show up as red lines
in the white developer.
The method is relatively cheap and easy to apply, but will not give 100%
guarantee: when the cracks are full of oil, grease or paint the
Penetrant Red cannot enter the cracks and therefore not show up.
The method is described in ASME T-640 and T-644.
Jack Aeckerlin, The Netherlands
1964 BJ8 29432
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