Quote:
Originally Posted by Kirk
Absolutely! Bearings are NOT happy if they are not lubricated. We've had this before at my factory - a piece of equipment is returned from rebuild. It's not lubricated by the rebuild shop. We assume it is and put it in the machine. How long do you think it lasts?  Not long!
This is from the LN Engineering IMS Retrofit website:
See that tiny slit between the IMS shaft and the IMS bearing cover? That's what the IMS Retrofit depends on to get oil bath, splash, or mist lubrication from. That's what scares me about that solution - there is not a great, reliable path for consistent lubrication. Now if you could pump in oil from inside and just let it drain out of that slit you would end up with the area between the end of the shaft and the cover filled with oil - thus flooding the bearing at all times. Both the TuneRS DOF and IMS Solution plain bearing put oil inside and drain out of this slit. I don't see why aeration or anything else would be a concern in either application.
Kirk Bristol |
The example from the photo posted is equivalent to the gap on the dual row IMS bearing and flange assembly. That photo is actually a quadruple row IMS Upgrade we used to do on dual row bearing IMS shafts. We used conventional bearings in the very beginning, of which there are probably a dozen or two still in service.
The LN single row IMS Retrofit kit actually has a larger gap and we actually redesigned the flange last year providing an even larger gap to allow significantly more oil to get in there along with cryogenic treatment of the single row ceramic hybrid bearing to further improve the wear characteristics of the bearing races. However marginal an increase, we found a study claiming positive benefits of the process for 52100 bearing steel.
To quantify the lubrication requirements of the IMS bearing, I had a lengthy discussion with our bearing manufacturer and the lubrication requirements for a ceramic hybrid bearing are minimal and that barely more than one drop per minute is required, so about 1/20th of a cc.
As such, I will re-iterate that the IMS is submerged in oil and there is more than adequate lubrication with an open bearing in the M96's wet sump.