mounting roller needle bearings?

Hi,
I was looking at roller needle bearings to use in wheels. I
didn't realize, believe it or not, that many of the heavy-duty casters
come with needle bearings. Cool, saves time and $ :-)
So, to double check-- with a ball bearing, the shaft is locked into
the bearing with a locking collar or otherwise. But with needle
bearings, there is no inner raceway, the rollers are left exposed. So,
if the ID is 1", can I just slip a 1" carriage bolt through and bolt
the caster to whatever surface I need it hanging off of? Or is there a
press fit of sorts with the rollers?
thanks!
-Bernard Arnest
Reply to
Bernard Arnest
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the bolt thru will work but will wear out unless you case harden it. Brian.
Reply to
bfairey
Man, it would take a long time. I've got a bolt with needle bearings on my irrigation traveler wheels. It goes several miles per year and its ten years old. Still no visible wear.
Reply to
Karl Townsend
Hey Bernard,
As with many products, options change with size. What is it that you have? Are they "loose" and held only by a cage arrangement, or are they packed into an OD sleeve? Lots of them come with an external thick "skin", like for a U-joint or for press in place. I believe that for some uses in some sizes, Torrington needle-bearings can be purchased with separate sleeves for both OD and ID. This allows use on surfaces (both the shaft and the housing) that may either not be metal, or that are too rough for some reason to use, or other reasons I suppose. But I don't think that they are available for all sizes, so check with the bearing supplier.
Take care.
Brian Lawson, Bothwell, Ontario. XXXXXXXXXXXXXXXXXXXXXXXXXXXXX
Reply to
Brian Lawson
Hi, I'm unsure. I was just going to buy a heavy-duty caster, remove the mount, and rebolt it to my machine. It is presumably already solidly mounted into the caster. Whether the ID is open or not shouldn't matter, I'm guessing?
thanks! -Bernard
Reply to
Bernard Arnest
First; are you talking about these: "Steel Needle-Roller Bearings" on page 1057
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The needle rollers can be used with a bolt but the needles MUST run on a round part of the bolt, NOT the threaded portion! The shaft/bolt will wear badly if it is not hardened. We used a 1" id x 1-1/4" od bearing, had extensive shaft wear in 6 hours of heavy use. Changed to a hardened shaft, all was well. If you intend higher speeds (perhaps 100rpm and up) you will also want the shaft to be round and to spec (see bearing mfg) Typically the bearing housing is designed with a press fit to a standard size (deg .001" to .002" under nominal) and the bearings have proper clearance for a nominal size shaft (eg bearing is .002" over nominal)
I'd suggest using a grade 8 bolt, use machine washers to properly space it away from the chamfer near the head and the threads.
These things like lots of grease if you want long life. The outer case has grease hole, set up a zerk fitting to match. Or drill a longitudinal hole in the bolt with a cross hole and add the zerk fitting to the end of the shaft.
Bernard Arnest wrote:
Reply to
RoyJ
A hardened and ground axle will surely work better than a bolt. Maybe the shank of a 1" HSS endmill without the weldon flat, TIG weld a threaded part to one end and a head on the other end.
Reply to
Don Foreman

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