OT: Ring Fetter

Ok I got stuck helping with the mechanical on a project and part of this machine needs it's ring fetters replaced and I can't get much info on that part of it without taking a plane to china of which I wish to avaoid.

Doing google Fu of ring fetters gives lots of results of ring feders but that's something for trucks and trailers / equipment.

Is this what might be classified as a ring fetter?http://www.fennerdrives.com/b-loc/?=&s=cHwy&v=grid

Is ring fetter an older term or a trade term perhaps?

Your Link was in the ballpark, You are looking at a keyless bushing basically.

The brand is RingFeder and here is the link: http://www.ringfeder.com/en/international/products/ringfeder/?g=381

Mark Snodgrass

The Plc Kid said:

Ok I got stuck helping with the mechanical on a project and part of this machine needs it's ring fetters replaced and I can't get much info on that part of it without taking a plane to china of which I wish to avaoid.

Doing google Fu of ring fetters gives lots of results of ring feders but that's something for trucks and trailers / equipment.

Is this what might be classified as a ring fetter?http://www.fennerdrives.com/b-loc/?=&s=cHwy&v=grid

Is ring fetter an older term or a trade term perhaps?

Click to expand...

Ringfeder is a manufacturer of couplings. What you linked to is what I would refer to as a keyless taperlock bushing. QD bushing is another term. Do you know where these Rinfetters are, what they look like, or why they need to be replaced?

From what I understand these should only be used one time? If you have to remove it then best to replace it as using it again it will not hold as well?

Any truth to this?

The Plc Kid said:

From what I understand these should only be used one time? If you have to remove it then best to replace it as using it again it will not hold as well?

Any truth to this?

Click to expand...

In my addmittedly anecdotal experience, I've had no trouble with removing and replacing them, provided both the coupling and shaft were in good condition. Probably best to ask the manufacturer though.


-rpoet

rpoet said:

In my addmittedly anecdotal experience, I've had no trouble with removing and replacing them, provided both the coupling and shaft were in good condition. Probably best to ask the manufacturer though.


-rpoet

Click to expand...

I'm with rpoet, I can't imagine why you couldn't use these more than once (we do it all the time), but maybe there is something special about your particular style? I would ask the manufacturer as well.

Are you sure it is a ring feder? Each manufacturer has thier own specs. I usually use B-Loc ( my local sales rep is very good). In a former life I used them weekly. They can be reused as long as the surfaces have not been damaged by mechanical or chemical means. I had a large unit on a 24" shaft that was submerged in oil. The manufacture recommended we not reuse this because the oil has obviously gotten between the friction surfaces and will reduce the coefficient of friction. We had to re used it because if lead time issues. The rep had us bake it in an oven for a few hours after everything was cleaned over and over. It turned out just fine.

Shrink disc, squeeze lock, ring fitter( spelled any way you want) are just a bunch of trade names.

Make sure you follow the installation spec to the letter. If you torque the screws out of order or sequence you can scrap the disc and the mating surfaces. I have seen this unfortunately way to many times with old hammer mechanics. Some flange sytles torque every other or crisscross. Flangeless usually start out crisscross until you hit 75% of torque then change to every other one.
I prefer to use a torque wrench that has the target range in the upper 50% of its range to increase my accuracy. Example my target torque is 100 ft. lbs. I wouldn't use a 1/2" wrench with a 250 ft lbs range because the target range is under the 125 ft lbs mark on the 1/2". I prefer to use my 3/8" rated at 150 ft lbs. I typically use increments of 10% , 20%, 25% 50%, 75%, 90%, 95%, 100% of final torque. Number every bolt in the tightening order. I go around the shaft at xx ft lbs until no bolt moves. If one bolt moves go around it again at that torque.

Sorry for the long post this is something that I might be abke to help someone with.

Jeff is correct. Take your time to torque them correctly. Different mfrs have different specs, usually mounting instructions come in the box.
Properly installed they will transmit more torque than a key. They are excel for high torque fwd rev cyclic loads.
A "round" shaft is not perfectly round but 5 or 7 sided. When installed correctly a torque coupling will grip more of that irregular surface.