I have lifted 110' of Rohn 65G with ring rotators from the top with no
issues and even longer pieces by attaching the crane to the the side. It
is much easier to plum if attached at the top, but that is not an issue
for removing the tower. I am not understanding pinning the legs, I have
installed the tower twice and removed it once and saw nothing that seemed
difficult to control.
John KK9A
To: Wayne Kline <w3ea@hotmail.com>
Subject: Re: [TowerTalk] [Bulk] Re: [Bulk] tower removal
From: Grant Saviers <grants2@pacbell.net>
Date: Thu, 10 Mar 2016 14:46:14 -0800
Wayne,
Yup, the bottom loose end of a 1 ton 130' (plus mast?) long battering ram
swinging around is a scary thing! A big jump from R25.
Rohn does have a spec sheet for the tower section mechanical properties,
that would be best to find it for 65 and ask the question to a real
ME/Structural Eng. if you want a single point lift.
You need a really big crane to hoist one ton plus plus the layover reach.
I think the crane ops don't like to see a chance of the load getting
snagged on the crane boom, so that means the crane tip higher than the top
of the mast. The crane company here sent out the boss to scope out my job,
that might be a good place to start.
We lifted each section individually after the first 40' pair for my tower,
the crane was at max on the top section with one ring, prop pitch, 22' of
3" mast, 14' exposed, 1100#. 156' to mast top AGL.
Let us know what you learn.
Grant KZ1W
On 3/10/2016 13:16 PM, Wayne Kline wrote:
Grant,.
I am disassembling my 146 ft Rohn 65 (20 ft sections) and one tapered base
that was converted
To a top section. When I installed it I used a crane in two lifts first
lift @
60 ft. Then attached the guys to the anchors , then the last lift with the
attach point @120'.
I did not do the moment /math. But am concerned in removal the 130 ft in
one shot. Leaving 16 ft stub.
The anchoring it to the ground and the layover ???
I helped in removal of two towers one @ 110 and one @ 100 with24ft of 1/4
wall cromemolly tubing and yagi monobanders. One lift up and then we
laid it
down and di assembled the antennas at ground level.
The trick in this process is to keep the tower anchored , the crane ooperator
keep the free bottom legs pined against raised concrete base as he turned and
lowered the boom.
But R 45 is 80 lb and R 65 for 20 ft is 298. And my concern
Wayne. W3EA
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