For single row tapered roller bearings, they work as Roger describes.
They will fall apart so need retained and preload applied to insure
everything stays in contact when load is applied. A car produces push,
pull, and radial loads on the wheel tapered roller bearings. The parts
are the cup and cone (goes on the shaft) and are purchased separately
for larger bearings.
The spherical dual roller bearing described in the post that started the
thread is designed to accommodate significant shaft angular
misalignment. That would occur when the tower leans in strong wind.
They are not intended to come apart and the preload/clearance is
established in the precise grinding of the parts.
More on bearings: Needle bearings have no axial load capacity and
thrust ball or roller bearings have essentially no radial capacity. In
between are angular contact bearings, usually made in super tolerances
(ABEC 7 or 9) for machine tool spindles. These spindles need to handle
loads in all directions. They come in matched pairs, and a Bridgeport
mill set (not Chinese) costs ~$700. Some models of rotators (Yaesu,
HyGain) have the aluminum races shaped as angular contact bearings so
both axial and radial loads can be applied.
Deep groove ball bearings are primarily radial bearings but can handle
axial loads of 25% or more of rated radial load per specs.
Grant KZ1W
On 7/15/2017 19:32 PM, Roger (K8RI) on TT wrote:
I'm not a mechanical engineer, but pretty sure. Those bearings receive
a substantial load, not only on both axes, (cornering) but off axis as
well. (momentary or short term impacts). The race is not only tilted,
but tapered so those rollers support load along their entire lengths.
Note, the race taper is roughly 20 degrees off horizontal as the
primary, long term is horizontal, while short term (but substantial)
loads are mainly, or close to, in line with the axles although impacts
may be at almost any angle off the rims.
73, Roger (K8RI)
On 7/15/2017 Saturday 12:20 PM, Jim Thomson wrote:
Date: Sat, 15 Jul 2017 01:56:37 -0400
From: "Roger (K8RI) on TT" <K8RI-on-TowerTalk@tm.net>
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Bearings for Axial Load
<Roller and ball bearings work well for side loads. Ball bearings in a
<horizontal race can support substantial loads. Roller ans ball bearings
<typically work in one axis at a tine. It takes a tapered bearing, like
<a wheel bearing to do well on both axes.
<73, Roger (K8RI)
## u sure about that ? A tapered bearing, like a wheel bearing, is
designed
to be mounted horizontal. Mount it vertical, and all the load ends
up on the bottoms
of those shafts that go through the tapered bearings... on the now
horz section, that all those
vert shafts are connected to. . Im sure it was on your site that
depicted broken shafts..that go through the center of the tapered
roller bearing. IF the wheel bearing was
big enough to begin with, and 2 of them were used, it should not be
an issue. IF the rotor in question had
the entire weight of the mast + ants on it, then there would be no
weight on the bearings either... only
an axial load, when the wind blows.... moot point.
## I dont know what type of bearing the speer brand is..... thats
used in the UST crank-ups, but they are
built like a tank...and come with locking collars. I used 2 of
em... + a K7NV small PP.
Jim VE7RF.
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