NDT for Expansion Joint/Bellows

Is the material ferrous? If so then Mag particle.

X-rays?

Problem is if you are more than 5 degrees off the center-line of a crack using x ray , it is unlikely to be able to detect a crack. As bellows are a constantly changing angle it would yield very little. If the cracks are all in the same area and not random orientated then an ultrasonic surface wave around 5 Mhz would work.

I'm glad that's in the open.

More than UT, PT, RT you can use:

1.-Halogen Leak examination

2.-Mass spectometer examination

3.- Air Jet Examination

Try to find "Standards of the expansion joints manufactures Association"

EJMA_7ED

http://www.ejma.org/EJMAStandards.htm

WP

Blue dye, a dentist's mirror, a magnifying glass and a light. Apply the dye to the surfaces, let the dye dry and look for anomalies of the dye on the surface. This method is used for finding cracks in glass lined reactors. It is also used on some metals to find holes, cracks and surface irregularities.

Seal the ends, apply air pressure to inside and coat the outside with soapy water and watch for bubbles, just like checking for gas leaks on gas piping.