Date: Mon, 3 Sep 2012 17:22:15 -0700
From: Jim Lux <jimlux@earthlink.net>
To: Steve Maki <lists@oakcom.org>
Subject: Re: [TowerTalk] Crank-ups.....do NOT lubricate your cables
from US tower
I suspect that rigging companies and crane ops also do regular inspection and
cleaning of those cables too, just like the ones on gondola and chair lifts.
On Sep 3, 2012, at 17:05, Steve Maki <lists@oakcom.org> wrote:
> I wonder why crane companies keep their cables (on million dollar cranes)
> lubed religiously?
>
> On this particular topic, I would not place much faith in the manufacturer's
> edicts, unless you're looking for a reason to keep busy replacing the cables
> more often than otherwise needed.
>
> -Steve K8LX
## all the local ship yards around here have 55 gallon drums of pre-lube
6, 9, + 11. This stuff is literally
poured onto those cables, right at the drum, via an oiler device. Its just
penetrating oil, to lubricate the inner strands.
Nobody is changing cables every 3 years. UST also wants me to check the oil
in the gearbox every month, and also
change it out every 2 years. Turns out those hub city gear boxes were never
meant to be used for lifting applications.
They were designed for stuff like conveyor belts, etc. They are actually
called ....speed reducers. They were never intended for
a hoist application. The UST control box on the tower is not water proof nor
is enclosed in anything remotely close
to a nema box. Whoever designed their anchor bolt configuration + rebar cage
on the HDX-689 was clueless. Neither
meet any spec here in town. If you put a 14 foot mast out the top of their
tower, you can kiss that 70 mph rating goodbye.
I wouldn’t be using the UBC-97 exposure B specs either, use exposure C, or
use the RS-222 rev g specs....if you can find em.
The story I got from the crane and ship yard folks is... without the use of
the various grades of prelube slopped onto the
cables, the inner strands can rub together..and break. You cant see internal
damage from the outside.
It would be nice if UST provided detailed instructions on how to re-cable
their towers. They insist you recable their
towers, but then wont provide the info. Check out their info on how much
torque required for both the anchor bolts +
leg bolts..... answer, snug fit. What kinda BS answer is that.
Jim VE7RF
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