Super Nut

never heard of a super nut till now.

I don't know if the old time CR4 members should be taking this "super nut" posting personally.

I"M OFFENDED...... ^{I think}

Or,.....

Thank you, my pape always told me, what ever you do, be the best you can at it.

Sounds like a Rocky And Bullwinkle ending.

more than a handful

RIGHT!!

I don't think this was the intended path of the OP.

This has the recipe of fitting right into "Caption This"

Are you asking for:
1.- Thermal torque?
2.- Tensioning torque?
In both case you have to evaluate the Nuts and Bolts (NDE and elongation test). Most of the times you can reuse the same Nuts.

The only thing I could locate about a super nut is a Japanese manufacturer making what looks like their version of PEM inserts. I do not know if this is what the OP is referring to but it might be.

The crux here is what the OP means by "extended use". If the first definition for extended describes this nut then certainly any stretched nut and bolt should not be used again and a replacement should be used. If the second definition of extended applies then I am uncertain. Any part that has lasted longer than it was intended to last should probably not be used again if a significantly newer part is readily available. However the uncertainty comes from who and how one determines this is an extended period of time.

Did you notice they make a range of Sex Bolts?

oh, oh

These super nuts should certainly not be reused.

And please keep them out of the reach of children.

I'd like to apologize for my nutty comrades. They go nutso often.

Do any of these fit the description? Your comment, "reuse supernuts after an extended use" makes no sense, unless you define the conditions of use and length of time in service. What is "extended use"?

When in doubt, don't.

yep, I had to google it also to find out what a super nut is.

Most if not all bolts used in high torque applications should not be reused....If any fastener has been used in a situation or circumstances that has changed the properties of the metal being used, it should not be reused....metal fatigue will weaken the fastener and jeopardize it's reliability....this is especially true where the failure could cause extended damage to equipment or personnel....

http://en.wikipedia.org/wiki/Category:Mechanical_failure_modes

Do supernuts mate with superbolts?

http://www.nord-lock.com/superbolt/multi-jackbolt-tensioners/

Nobody better be making fun of me, or I'll get "Super Mad"

Or are we perchance talking about leadscrew nuts?

http://www.thomsonlinear.com/website/com/eng/products/ball_screws_and_lead_screws/lead_screws.php

Possible, Thompson do have "Super Smart Bearings"

The also have

"Thomson Lead Screws - Supernuts

Thomson BSA® precision lead screws are an excellent economical solution for your linear motion requirements. For more than 25 years, Thomson BSA has designed and manufactured the highest quality lead screw assemblies in the industry. Our precision rolling machines ensure accurate positioning to 0.003 in/ft and our PTFE coating process produces assemblies that have less drag torque and last longer."

But then again...

http://catalog.zodiac.nl/en/Catalog/10+Final+Drive/Final+Drive/Sprocket+Hardware/THE+SUPER+NUT+FOR+BIG+TWIN+TRANSMISSION+SPROCKET/Product.aspx

As I said, this is the first time I heard about 'super nuts', I must be alone on this one.

But it all depends on the user, Up until about 4 months ago, I never heard of 'Super Smart Bearings' either, until I spec'd them out.

The "Super" label I'm sure is just a advertising lure.

Im sorry I realize it may have been a little vauge super nuts are multiple contact high torque nuts. And extended use is 7 years of high vibration and pressure. I have been in maintenance field for 20 years and was always( since they started being used more regularly) told to never to reinstall them due to fatigue. I was told last night at work ( new job) that I had to be careful and take them off a old machine in the manf.recomended way to reuse. Just wanted to get the opinions of other professionals.

What you really need to do is follow your own organisation's procedures.

Written Procedures or Verbal Procedures?

I agree, always follow your organisation's procedures as well as you can. Particularly when the procedures are formally documented. IMHO one should feel free to initially (but not repeatedly) politely question any procedure, particularly when they differ from your previous experiences. This can highlight a flaw (ambiguity) in how the procedures are written or on a rare occasion an unexpected liability.

As you should notice from this thread, the use of vague terms and unfamiliar jargon can quickly lead to humorous if not dangerous misunderstandings.

You still haven't supplied a proper specification for these things. If I put "multiple contact high torque nuts" into a web search, it comes up with "About 3,450,000 results" - the first result being a reference to "Superbolt multi-jackbolt tensioners" (as I referenced in an earlier post).

Do you know who manufactured these things, who sold them, or what part number specifies them? Can you provide a link to them (or something similar)? Can the bloke who introduced you to "Super Nuts" shine any light in this direction?

Do they look like this?

ma21313,

Do you have a link to them, please?

If you are in fact referring to the multi jack nuts as pictured by Lyn in #35, then I have seen them reused many times. You do have to be careful undoing them as each individual bolt is under extreme pressure and each must be slightly loosened/tightened sequentially to prevent damage to the jack bolts.

From what I have seen, they work well as the tension obtained is quite phenomenal (especially considering the low torque required to do so), and whilst this doesn't appear to affect the nut as they are tensioned under straight torque conditions which seems to eliminate galling of the threads, I have seen some stretching of pretty large diameter bolts that they were used on. This may necessitate replacement of the bolt before the nut needs so doing.

Southpark, is probably the best authority on this:

"...Dumbass, you can only milk a dog once every few hours. It doesn't work if you beat off the dog again right away...."

.

The rules of Red Rocket likely apply regardless of whether it is a dog or other animal, and whether you would rate the nuts as super or not.

A lunatic escaped from the asylum, raped some women in a laundromat and is now on the run. The newspaper headline read, "Nut screws washers and bolts."

Well if you believe whoever told you, then maybe you will believe an anonymous post on the internet. NO - don't reuse them!

Isn't that supposed to be "soup to nuts?" In which case, you'd have to worry about food poisoning.

Is it a nut which once tightened will never become loose?.

If your boss says reuse them, do so, but with some kind of written verification that you were acting under orders. Touchy situation. Been in it many times, mostly about brake rebuilds. Also galvanic corrosion on boats. Now it's about radiation from cellphones. The morons keep marching.

It depends on how long your refractory period is.

There is no right or wrong answer to the question (although some here remind me of school yard children). It really depends on the use of the units and how careful the tech was in installation and removal. I have used and reused these units in some very nasty places. I praise them highly for the ability to lock a unit in place with out worry of coming apart. To-date I have had no failures with new or reused units. Like I stated I use them in a steel mill, which is very nasty place on any fitting and fastener.

It seems NASA like these as well as they may of had a little hand in the design some years back for shuttle or something like that.

Fixit