Anyone know if there is such thing as a pneumatic swing arm clamp (DeStaco
type) that has a dry contact electrical switch to provide a "proof of open
clamp" signal? Can't be moving or rotating that pipe if the clamps are
still closed... And I can control the clamp close / open cycle with my
pneumatic controls but can't provide a "proof of open clamp" signal to his
PLC without an integrated product...

When I worked for the big corporation, we often used magnetic proximity
switches for this sort of thing. You've just got to find a place where you
can drill a 1/4" hole and imbed a magnet. The switch itself closes when the
magnet is within a 1/4 inch - non contact and good for 100,000s of cycles.

Karl