Specs for stainless steel screws with nylon locking elements 3

[Tunalover]

Does anyone out there have military or aerospace specs for stainless steel screws with nylon locking elements (plugs, patches, pellets, etc.)? These would be specs providing part numbers to buy them to.

TIA




Tunalover

 

[kenvlach]

These are usually called PEM^[®] nuts, etc. from the original name of the manufacturer, Penn Engineering & Manufacturing Corp. Their website mentions complete testing to NASM 25027, 45938, ASTM & PEM Fastener tests. Lots of product literature, CAD drawings, a technical library, etc. at

http://www.pemnet.com/

 

[Tunalover]

kenvlach-
You're preaching to the choir about clinch nuts. I asked about screws, not nuts. Also, it would be news to me if clinch nuts came with nylon locking elements! Could you provide a PEM part number, for instance?




Tunalover

 

[kenvlach]

Screws are included in “etc.”

No, I apologize – I saw StickScrew^® on their homepage and didn't investigate.

Can you use self-locking hex. socket screws, 18-8 SS with nylon patch
(-70° to +250° F), per ANSI/ASME B18.8?
Thread sizes 4-40 to ½-13, catalog page 2924

http://www.mcmaster.com/

 

[unclesyd]

tunalover,
Just talking with my nut buddy and his comment was if you don't need a Mil-Spec fastener just ask for a Nyloc/Nylock/Nylok from an American manufacturer. This will insure a quality screw and save considerable coins. He has been seeing some poor quality imports in the Nyloc/Nylock/Nylok type screws.


Here is one he has been getting calls for. Look at the product specifications for all the standards

http://www.nylok.com/products_nylokpellet.htm

 

[Tunalover]

Thanks guys but my customers are pretty particular about the quality control that (supposedly) comes with MS, AN, or NAS hardware. I know that I can always go to a commercial mfgr. Also, AMSE B18.3 does not put forward a universally-recogized part numbering system.


Tunalover

 

[MintJulep]

Basic AN bolt chart here:

http://www.aeroparts.com.au/aircraft_bolts_from_aeroparts.htm

Nylon patch and pellet inserts for bolts and screw are governed by MIL-DTL-18240; which you may obtain here:

http://www.longlok.com/pdf/milspec_18240f.pdf

 

[Tunalover]

Thanks MintJulep, but we are looking to buy these using an industry-standard part numbering system. We always have the option of creating a vendor item drawing. Note that IFI-524 is another spec for locking elements.


Tunalover

 

[aviat]

Try:

http://www.longlok.com/pdf/handbook.pdf

 

[Tunalover]

aviat-
What does that provide?


Tunalover

 

[aviat]

Tunalover

It gives the means that the company uses to number their screws.
I don’t believe there are any AN, MS or NAS screws with the inserts installed. This company takes screws and adds the inserts. I think it would be cheaper to use locking nuts or anchor nuts than those inserts.

 

[MintJulep]

Tuna,

The Long Lok handbook has a bunch of good information on prevailing torque fasteners. It is well worth the free download.

I also, I think, points you to the answer to your question, which is:

NAS 1283, and MS 15981

 

[Tunalover]

MintJulep
Thanks for the links. MS15981 tells how to apply the locking element but it doesn't appear to put forth mil-standard part numbers. NAS1283 I could not find using the DLA's website for free specs (ASSIST Quicksearch).


Tunalover

 

[vti]

Try NAS 1351 or 1352. These are fine and coarse thread socket head cap screws. You can specify with or without a locking element.

 

[Kenneth]

NAS1189, NAS1190, NAS1635, NAS6303 thru 6320, NAS703 thru 6720, MS21095, MS21295 ...

 

[Tunalover]

vti and Kenneth-
Thanks guys! You're a big help. I'll get these specs.


Tunalover