Never seize on SS Bolts/Nuts?

[Lost_in_the_HTTP]

There is a longer story about decks and trailers, but I'm not planning on getting into that.


The point is SS is rust resistance, so is there any advantage to using Never Seize on them? Disadvantage?

 

[Micrornd]

Stainless Steel, quite a misnomer. SS only starts to become true with the 400 series and higher, below that, it is just added rust and corrosion resistance. (i.e. the major difference between 304SS and 316SS is the length of time before rusting)

Anti-Seize, Never Seize have nothing to do with and no real effect on rusting or corrosion, more than a simple grease coating would (i.e. covering the metal to prevent exposure to atmospheric and chemical agents. Anti-Seize, Never Seize should only be used on metal to metal contact and fastening, it is not needed for other contact (and should not be used) aa it can even act as a lubricant or abrasive if used on moving surfaces facilitating undesired movement or mechanical erosion. SS into wood/PVC/plastic (or any softer/less dense material) would be an example of definitely where not to use Anti-Seize, Never Seize as it would act as a lubricant allowing (forcing) the fasteners to back out of the material due to the movement (expansion, contraction) of the material.

Anti-Seize, Never-Seize are used to prevent galling (seizing from mechanical friction) of SS to itself or other metals. This is essentially the fusion of the metal between to surfaces (this is a highly simplified explanation). It can be 2 similar materials (SS nut and bolt) or dissimilar metals (SS bolt and steel nut). The all SS combo galling would be caused by mechanical pressure (simplified explanation) and the SS-steel combo would be caused by chemical reaction (rusting) (simplified explanation). In both cases the Anti-Seize, Never-Seize acts as a separator, becoming a very thin layer, preventing contact (or greatly reducing contact of) the metallic surfaces, while still being a thin enough layer that allows a usable amount of torque to be applied to the fastener.

Anti-Seize, Never-Seize can also be successfully used in simple pressure (not torqued) applications, such as the flat surface of an aluminum alloy wheel that comes in contact to a steel disc brake hub.

IDK, is there an answer in there for you?

 

[Fenixgoon]

Stainless Steel, quite a misnomer. SS only starts to become true with the 400 series and higher, below that, it is just added rust and corrosion resistance. (i.e. the major difference between 304SS and 316SS is the length of time before rusting)

Anti-Seize, Never Seize have nothing to do with and no real effect on rusting or corrosion, more than a simple grease coating would (i.e. covering the metal to prevent exposure to atmospheric and chemical agents. Anti-Seize, Never Seize should only be used on metal to metal contact and fastening, it is not needed for other contact (and should not be used) aa it can even act as a lubricant or abrasive if used on moving surfaces facilitating undesired movement or mechanical erosion. SS into wood/PVC/plastic (or any softer/less dense material) would be an example of definitely where not to use Anti-Seize, Never Seize as it would act as a lubricant allowing (forcing) the fasteners to back out of the material due to the movement (expansion, contraction) of the material.

Anti-Seize, Never-Seize are used to prevent galling (seizing from mechanical friction) of SS to itself or other metals. This is essentially the fusion of the metal between to surfaces (this is a highly simplified explanation). It can be 2 similar materials (SS nut and bolt) or dissimilar metals (SS bolt and steel nut). The all SS combo galling would be caused by mechanical pressure (simplified explanation) and the SS-steel combo would be caused by chemical reaction (rusting) (simplified explanation). In both cases the Anti-Seize, Never-Seize acts as a separator, becoming a very thin layer, preventing contact (or greatly reducing contact of) the metallic surfaces, while still being a thin enough layer that allows a usable amount of torque to be applied to the fastener.

Anti-Seize, Never-Seize can also be successfully used in simple pressure (not torqued) applications, such as the flat surface of an aluminum alloy wheel that comes in contact to a steel disc brake hub.

IDK, is there an answer in there for you?

Your distinction between 300 and 400 series is wildly inaccurate. And I can say this because I'm a metallurgist. Though you are right in that no stainless is truly stainless..they're all stain less.

There is a longer story about decks and trailers, but I'm not planning on getting into that.


The point is SS is rust resistance, so is there any advantage to using Never Seize on them? Disadvantage?

Anti-seize will reduce friction and provide additional corrosion protection

However

Because it reduces joint friction, you'll get more preload at the same applied torque. This can result in over tightening and bolt or joint failure.

Is there a very specific torque requirement? What grade is the OEM fastener?
If there is a large margin between the fastener strength and the design preload, you're probably ok. Smaller fasteners are more sensitive though and can be very quickly over-torqued

My recommendation is to not use annealed stainless steel fasteners, which off-the-shelf are probably going to be grades 301, 302, or 304. Make sure you have a grade5 or grade 8, whichever is grade-equivalent to the OEM fastener. Annealed stainless fasteners are more prone to galling, and probably aren't going to achieve the required preload on account of their low strength (because they're annealed)

Edit:
I should add that a traditional steel fastener with a good coating can have just as good or better corrosion resistance than a stainless fastener depending on the application. Had a work project on that once..

 

[Lost_in_the_HTTP]

They're holding a plywood deck to a pre- Harbor Freight type utility trailer.

Not making fighter jets here.

Nut is under the deck, road side where it gets all the goo and sits for months or years.

 

[Stopsignhank]

The smarter than me people have already answered. I will just tell you that I was the facility manager at a manufacturing place that had to use stainless steel nuts and bolts.

If you use stainless steel nuts and bolts they will gall, seize up. It would take about 3 years at my best guess, give or take a couple years here and there. It would be a real bitch to get them apart. Usually something broke or was cut.

My recommendation is to use the anti-seize. Just because I like to be able to take things apart if needed. If you are worried about them staying together you could always double nut it if you have the room.

 

[lxskllr]

Might want to look at something like this...

FLUID FILM | Powerful Corrosion Protection & Lubrication

FLUID FILM® is Eureka’s own unique lanolin-based brand of corrosion preventive and lubricant, used worldwide in a multitude of industries and applications.

www.fluid-film.com

I have it on my truck chassis. It came already rusted from the north, and I'm trying to slow down the spread. I can't vouch for it as of yet, and I haven't tried it on virgin steel, but it was recommended to me. I like that it's non toxic, and not nasty to use. It distinctly smells like sheep. You may or may not mind that. You'd have to periodically reapply. Maybe once a year, but it isn't hard. Specifically for nuts/bolts, the brush on applicator would probably be best. I used spray cans for the truck. Took two cans to cover the steel underneath, with some left for my chipper.

 

[Lost_in_the_HTTP]

I tried it on some tractor stuff.

First rain, it all washed off.

 

[lxskllr]

Huh... I have some on the front bumper, and it still looks wet when it's dry out, and that's getting blasted by everything on the road.

 

[Fenixgoon]

My go to is the nickel anti-seize paste. 1 $15 bottle will last a lifetime.

 

[Micrornd]

Your distinction between 300 and 400 series is wildly inaccurate. And I can say this because I'm a metallurgist. Though you are right in that no stainless is truly stainless..they're all stain less.

While I congratulate you on your education and position, I base this soley on 40+ years field experience of using Anti-Seize products in corrosive environments and atmospheres, such as chlorine, salt water, sulfuric acid and hydrofluoric acid exposure, not on lab results or theory.

 

[Fenixgoon]

While I congratulate you on your education and position, I base this soley on 40+ years field experience of using Anti-Seize products in corrosive environments and atmospheres, such as chlorine, salt water, sulfuric acid and hydrofluoric acid exposure, not on lab results or theory.

I'm not saying you're wrong. I'm saying you're being inaccurate by making sweeping generalizations.

Those alloys are all developed on theory. They didn't pop into existence out of nowhere.

And I also have experience across a variety of fields that include the very things you listed. You definitely don't want truck and aircraft parts corroding.