heavy bearing grease
heavy bearing grease
(OP)
hello - i have a situation in a existing design that has 2 taper roller bearings on a shaft mounted to a single housing - there is no room on either side of the bearing housing to put a grease seal to keep the grease from seeping out - the grease will stay inside of the housing but will seep out on the out side of the bearings - i thought i have seen a particular bearing grease that is heavy or like a wax type substance - sort of like motorcycle chain grease that will not attract dust, dirt or water - it will stay put on the chain - any help or suggestions would be greatly appreciated - thank you





RE: heavy bearing grease
A properly selected grease works by allowing the oil to separate out of the soap to allow it to lubricate.
So with no seal, it's gonna' seep.
A not grease might work. Something like Dow Corning Molykote G807 or 112. But it's really very dependent on loads and speeds and temperatures. Talk to the tribologist from the bearing manufacturer.
RE: heavy bearing grease
RE: heavy bearing grease
The grease which as said above is oil carried by soap is designed to flow in and out of the bearing as the bearing works and is heated by the work. This not only keeps the bearing supplied with a fresh supply of oil, it cools the bearing. If the grease is too thick, it can't flow. If it can't flow, it can't lubricate and cool.
After a time, the soap and the oil break down - separate, and the depleted soap has to be pushed from the bearing by fresh grease.
Some bearing housings have tubes located high in the housing for the spent grease and oil exit point, and some just push it out past the seals.
In theory if the grease never wore out (broke down) it would just stay in there forever and do its thing. Unfortunately the world doesn't work that way hence the need to re-grease bearings to replenish the depleted grease.
Specific soaps and specific grades are recommended for specific bearings and specific applications. Your bearing manufacturer can provide you with what type or types of grease is required for your bearing and application and any alternate grades that might suffice.
Your job is to put the bearings in a housing where they can be properly lubricated, or use a sealed bearing which works as described above and keeps its grease contained inside (until the grease and soap separate when you will have to replace the bearing.)
Using a grease too thick or stiff can and will result in a bearing failure. I suspect you can find pictures on the net somewhere of bearings that are blue completely surrounded by new virgin grease that has never entered the bearing. If you can't find any, I can send you some if I can dig them out of my files.
This is not new science. You can probably find the above description on any reputable grease manufacturer's site, especially if they make grades for bearings.
rmw
RE: heavy bearing grease
RE: heavy bearing grease
Don't even have room for these ?
http://www.bearing-king.co.uk/data/images/3837.jpg
this wouldn't be a conversion from loose balls to TRBs on some motorcycle component, would it?
Dan T
RE: heavy bearing grease
great find & i thank you - unfortunately no not for a bike (wish it was!!) - still in the saddle but no time for riding anymore - hence my handle duk748 (my last ride was a ducati 748) - miss that very much!! - once again great help here - nice people too - have a great weekend
RE: heavy bearing grease