Steel AN thread, ??? AN cap

[efnfast]

If I'm welding a steel AN (male) fitting to a stainless steel pipe and plan to cap it, should I use a steel AN cap or can I use the aluminum AN cap? I just don't know if using the aluminum cap can cause it to seize overtime down the road? (this would be for a pipe w/ coolant flowing in it)

[oldguy668]

A little anti-seize, just on the threads, not the seating surface, will prevent that.

[efnfast]

True, but with coolant flowing through the pipe I wonder if it would effect the anti-seize somehow? Or maybe not?

[oldguy668]

Not. The coolant should never touch the threads.