Galling of stainless screws and pem nuts

[Peru]

I'm looking for ideas on what can be done to prevent galling of these components...

Both are class 2 8-32 threads. The PEMs are SP type...material for both is 300 series stainless and non-CRS is not an option at this point.

Problems occur with both tightening with a screwdriver by hand and electric driver.

I've tried anti-seizing compound and also graphite with limited success. Any ideas would be appreciated.

Thanks.

 

[Metalguy]

Use Nitronic 60 or equiv. Very resistant to galling.

 

[israelkk]

Silver plating the thread is a common solution.

 

[usjbh]

If this is a custom screw you can specify Carpenter Gall Tough or Gall Tough Plus stainless. If it is a standard off the shelf screw or a custom part that cannot accommodate the specialty stainless alloy lead time requirements you can specify Kolsterising

http://mcna.bodycote.com/

as a post fabrication surface treatment. We are in the process of implimenting Kolsterising for our high volume stainless screws instead of silver, gold or hard chrome plating as a cost effective alternative. The additional improved corrosion performance over 300 series base materials in addition to surface hardness performance for adhesion prevention (galling) is what we are looking for. We use all four processes in our products and others as well as many different alloys to avoid galling. Each has their own cost benefit tradeoffs to consider.

 

[CoryPad]

While the three answers above all can help, they may be much more costly than using a lubricant. Here is one for stainless steel fasteners:

http://www.fastorq.com/lubes.htm

Regards,

Cory

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