newshound wrote:
On 07/10/2018 18:21, harry wrote:
On Sunday, 7 October 2018 15:48:04 UTC+1, Chris Green wrote:
One of the UJT yokes on our Kubota tractor has failed, one of the
'arms' is broken so no longer retains the needle roller bearing.

Is there any sane way of repairing this as replacements seem nearly
impossible to find. It's a bit of a strange design as the yoke goes
direct onto a flanged shaft (i.e. it has an internal spline) so
finding a non-Kubota replacement is unlikely. However if anyone can
recommend suppliers of (small) UJTs with splined connections I'd be
interested.

--
Chris Green
·

It will be forged. Probably duff post heat treatment.

No fault, just worn away by long use.


On reflection I'm sure you are right about forging. But also on
reflection isn't it more likely to be a metallurgical defect than heat
treatment? That's why a photo would be interesting.

It will be a hard one to fix/weld.

Indeed (but we like them, don't we).

The reason for the splined shaft is that UJs do not rotate at constant
speed when out of line and axial movement comes in. The spline allows for
this.

although you only need one on the "intermediate" bit.

Yes, this is one of the 'ends' where it couples on to the driven
shaft, it's not a sliding joint. The sliding joint is in the middle
between this UJT and another.



I should concentrate on getting a replacement part.

I certainly would not ignore that possibility. It's not as if it is a
rare machine. You might actually find that parts from Chinese or Eastern
European copies fit.

I've looked for parts for this before and found the needle rollers for
the UJT but so far haven't found the yokes.

--
Chris Green
·