Aluminum Threads Galling - How to Prevent
Aluminum Threads Galling - How to Prevent
(OP)
I have a about a 3.5 inch tube connection that needs to be plugged with a threaded plug. The tube and plug threads are 3.5-10UN. Tolerance is 2A and 2B respectively. The tube material is aluminum, 6061-T651. The plug material is brass C360 half hard (H02) temper.
The idea of different materials was to try to eliminate galling of the threads - but there is some galling.
Any ideas as to how to prevent galling for this application? The desired plug material would be aluminum for weight, but again I am concerned about galling.
Would anodizing help?
Would a different type thread help? If so, any recommendations?
Thanks!
Bill
The idea of different materials was to try to eliminate galling of the threads - but there is some galling.
Any ideas as to how to prevent galling for this application? The desired plug material would be aluminum for weight, but again I am concerned about galling.
Would anodizing help?
Would a different type thread help? If so, any recommendations?
Thanks!
Bill





RE: Aluminum Threads Galling - How to Prevent
Anodizing would help.
If you want an engineered coating, try:
OKS 1700 from OKS
http://www.oks-germany.com
One of the Delta products from Dörken
http://www.doerkenusa.com
http://www.doerken-mks.de/
One of the 5XX coatings from Magni:
http://www.themagnigroup.com
Regards,
Cory
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RE: Aluminum Threads Galling - How to Prevent
Have the threads been inspected to make sure they are correctly formed?
KENAT, probably the least qualified checker you'll ever meet...
RE: Aluminum Threads Galling - How to Prevent
I have designed all sorts of aluminium parts that thread into one another. We have used much finer threads than 10tpi on diameters 3" and higher, and they work fine.
At least one of the aluminium parts must be anodized. It is better if both are. Forget about chemical film finishes such as Alodine.
Another solution is for one of the parts to be some other material such as brass. I am surprised this did not work. Perhaps you should follow Kenat's advice and check the threads. Also, watch out for thermal expansion and contraction.
JHG