galling in 6061 threads

[mrPelagic]

We have an intermittant problem with thread galling and seizing between mating 6061-t6 aluminum parts (an oil filled container and its cap). I know that this is a tricky situation, but there does not seem to be an option for us.

The pieces in question are of a diametrical range between 2 and 7 inches. We are not using the threads with any load- they are just used to hold the cap onto the container, and an o-ring surface in place. (Parts for sub-sea ROVs). The parts sometimes sieze when the cap is being lightly turned onto the body. We are using a 16 pitch thread cutter with our CNC process.

Has any one ever found a fix to this problem? Is there any coating that we can use to help eliminate the siezing?

thanks

 

[MikeHalloran]

Graphite, Molykote or Never-Seez will help. Teflon pipe tape will help. Anodizing one of the parts will help. Brass plating the threads on one part will help. A little of the o-ring lube would help. Anything but aluminum on aluminum will be an improvement.







Mike Halloran
Pembroke Pines, FL, USA