Fastener Locking

I came across this simple fastener locking method:

http://www.designworldonline.com/unique-fastener-inserts-reduce-risks-and-costs/?utm_source=EmailDirect.com&utm_medium=Email&utm_campaign=2013-03-20+DWD+Campaign#_

http://www.emhartamericas.com/brands/spiralock/technology

Maybe old news to those in the industry since it's been around for a while, (was used in Shuttle main engines).

But seems like a really simple solution that could be applied to both female and male threadforms, using only special threadforming profiles.

Anyone have real world experience with these?

Carter

erohslc wrote: Maybe old news to those in the industry since it's been around for a while, (was used in Shuttle main engines).

If it was used on the O-Rings of the booster rockets, maybe not a great solution..,.

But it was the O rings themselves that was the issue, not the fasteners.

The question I'd have is what does this thread locking application offer over say a vestible bearing or other type of thread deformation fasteners. Doesn't look all that special to me and I think needing special fixturing to tap holes might be an issue. I'll ask my old man if he has seen anything like this before, his job is to mechanically test fasteners and other weird aerospace type stuff.

That would require special taps at the least and maybe special dies. There are a bunch of more cost effective ways already out there.

In reply to Hal:

You did notice that only one of the threaded pair needs the wedgeloc threads, the other uses standard 60 degree threadforms?

So these could be retrofitted to virtually any machine on the planet.
Hmm, 'special taps ... and ...dies' that are used only once when the fastener is manufactured, with existing equipment, and requiring no additional machining operations or processing.
No safety wire, no lockwashers, no jamnuts, no nylocs, no locktite, etc.

'What a fookin' Nightmair!' (Mona Lisa Vito from 'My Cousn Vinny')

erohslc wrote: In reply to Hal: You did notice that only one of the threaded pair needs the wedgeloc threads, the other uses standard 60 degree threadforms?

I noticed that. I also noticed that the thread that uses their special form is the female thread. If you are going to use it just with nuts and bolts; no problem. The nuts can be tapped that way when made.

But what about all the fasteners that screw into a hole tapped into some part (engine block, etc.)? Do you think manufacturers are willingly going to retool to use this? And no you can't retap existing holes. Looking at their diagrams the wedgeloc does not remove as much material from the hole as a standard tap.

The other method that seems to be mentioned is some type of screw-in insert (similar to a helicoil). That would require you to buy their insert for every tapped hole in whatever you were bolting stuff to.

Hal, I think you will find that the wedgeloc threadform can be applied to male or female threads, since it alters only the tip of a standard 60 degree threadform.

I am NOT suggesting that existing holes be retapped, since that would NOT work.

What WILL work is that existing assemblies that use 60 degree holes (engine block, etc.) can be be retrofitted by employing studs/bolts that have threadloc threadforms.
What WILL work is that existing assemblies that use 60 degree studs/bolts can be retrofitted by employing nuts that have threadloc threadforms.

What changes are needed to manufacture pieces with threadloc ?
Special taps (in existing machines) to make threaded holes in new blocks or nuts.
Special dies (in existing machines) to roll threads onto new studs and bolts.

We are already willing to pay a premium for non-commodity specialty fasteners (ARP, SPS Carr, etc.)

So I don't really see an issue here.

Carter

So, back to my OP (nothing to do with how practical the wedgeloc threadform is), does anyone have real world experience with these?