Hello All,

Wonding if any of you know what kind of coupling this is. Where does it flex? Brand name? Max speed? It is on a 3600 rpm.
Sorry I do not have a better picture. This was take while it was running.

I investigated buying spare rigid coupling for one of our vertical motors. It turns out it was manufactured by the pump OEM and they were the only ones with the drawings to provide identical replacement.

Don't know if you will have the same results.

This message has been edited. Last edited by: electricpete,

It looks like a DeLaval pin type. It also looks old, rusty (small r), and 3/16" worn.

Pete,

This is a horizontal 3600 rpm pump center hung.

What about the rust coming out of joint? This isn't normal is it? What about the gap in the joint?

Slim,

I was wondering if this is "normal" (gap, rust, etc.). In my thinking, I would not think so.

Here are 2 more picture I found in the file.

Here is the second one. This one was taken in January. The others taken in June. Reported it as a Priority 2 in March. (Survey every 3 months) I guess nothing done. Data worse now.

Well the dust is "fretting" dust (rust, actually) from metal-to-metal contact. The misalignment of the match marks probably indicates wear (as Sam says). Either the flanges should be "tight" together and have been moving against each other, or the rubber bushings are worn completely out and it's running metal-metal inside the coupling. Either way, it will have to be replaced, preferably with something better.

Ralph,

My guess is that the axial position of the coupling hubs is too tight and possibly causing impacting/rubbing. The file photo appears to show a larger gap between the hubs with orange elastomer (rubber) showing. Possible corrective actions:
1) Inspect and replace elastomer elements, as needed
2) Set axial gap to specification
3) If no specifications and spare parts are available, then replace coupling
4) Measure and correct angular and offset shaft alignment

Walt

This type of coupling is (was) made by Renold and maybe Holset and some others that I can't remember. I would guess that you have some pretty seriously worn bushings. I'm not sure of the gap, but it doesn't look right to me. I have never seen any flexible coupling where the hubs are supposed to be in contact.

I have a client with a bunch of DeLaval pumps and all have DeLaval coupling that look that that and BTW -- the pump looks like a DeLaval or same configuration anyway. Pins and bushings may be replaceable if hubs are of sound integrity.

If it's a situation where operation demands positive rotation then a pin type would fit the bill. If you have shaft sizes then you may want to have one ready depending on the time frame outage and/or other considerations.

It never ceases to amaze me - what kind of engineering logic was used to make some of these selections........

be willing to bet you that the coupling wk-squared, etc., is a signficant fraction of the pump rotor mass (bad.....) and that it is improperly installed and applied......

Yea Don, but you get that beneficial flywheel effect which is like, free energy, right?