Weatherproof and low starting torque housing - Possible?

[bobp]

My requirement is for a bearing housing that is reasonably weatherproof (i.e. OK for outdoor use), and maintains very low starting torque (e.g. a non-contact labyrinth shield of some sort).

Currently my housings are bored out of Al round .75" to 1.375" d., use R4, R6, or R8 ss Conrad bearings (double shielded with oil lubrication) with spacers on a shouldered ss shaft, held in place at the housing opening with a retaining ring. Very low rpm (variable under 15 rpm) and very light loads (under 35 lbs axial and thrust on a set of two R8's).

These housings are embedded in the turning part and turn 360 degrees freely and are in turn rotated through all angles - outside in all climates -40 to 120F.

I am looking, ideally, for a machinable, inexpensive means of preventing water from entering the housing that can come to rest at any angle. It would be undesirable (but perhaps unavoidable) to have a grease filled housing with a zert, due to grease leakage and increased friction.

Any advise on designs or possible sources of info would be appreciated (I hope this isn't a holy grail).

Thanks, Bob

 

[FINN_imported]

I ahve run into a similar situation where the fit of the seal in the bearing was causing too much heat generation at high rpm. You may want to check with your bearing supplier about the fit of the shields in your bearings causing your friction problem.
I also have a possible solution to your contaminant problem. It is called the TRAKSEAL from Transcom Inc. Their phone number is 1-800-328-2840. I have heard use of this seal preventing bearing contamination in the rollers of a track-driven loader. It has not yet been cost effective for my projects, but maybe your product has enough annual volume to justify this type of seal.

 

[butelja]

Have you looked at labyrinth style bearing isolators, such as those offered by Inpro or others? Information on them is available at

http://www.inpro-seal.com/

. I'm sure there are other manufacturers who make similar devices, but this is the brand I'm familiar with for pump and motor bearing applications.

 

[bobp]

Thanks for pointing me in the right direction - It was the whole series of labyrinth shaft seals I was looking for - plenty there to design around.