Greetings, TowerTalkians --
There have been several threads over the last couple of years regarding
Rohn manufacturing problems - specifically 25G and 45G. Recently I've gotten
some more input. One is that Rohn has been laying off people due to declining
sales. One person laid off was an ex-TowerTalkian engineer who occasionally
contributed to TT. Here's what he had to say:
>> The Frankfort plant manufacters the small guyed towers and to be quite
frank there is not anyone there that knows how to design them. The plant
manager there wanted me to move to their plant but I couldn't live in such a
small town. They hired Jeff Butts in Frankfort, but he is not a structural
engineer. He use to call me up for help if someone asked a question that was
over his head. The Peoria office (where I was) is concerned with the large
towers and poles. When I was there, I sort of took it on myself to make sure
that any problems with ROHN towers mentioned on your reflector were taken
care of. Now that ROHN has cut back I'm not sure what kind of service the Ham
operators and others will get. >>
Not good news for anyone.
I also got the following from a local radio club who wanted to replace
their 25G with 45G for their VHF/UHF site:
> > Nearly a year ago we had to dismantle
> > our old Rohn 25 because it had corroded at the base. We applied to the
> > Cowlitz County Building and Planning Department (Kelso, WA) for a
permit
> > to replace the tower with a Rohn 45 100' guyed tower. We got our SEPA
> > report completed and bought the new tower. We were informed by
Building
> > and Planning that before we could put it up we would have to have the
> > welds tested by a professional engineer. We hired PSI Engineering,
> > Consulting and Testing in Portland, OR to perform a radiographic
> > inspection of the tower. PSI reported that all of the 10% sample of
> > welds failed on the basis of porosity. We did not give the report the
> > Building and Planning. Instead, I contacted Jeff Arends, of Rohn, who
> > furnished sealed drawings of the tower as well as a copy of Rohn's
> > Welding Engineering Standards. This did not sway Building and
Planning.
> > They were adamant that we present them with test results from a third
> > party certifying the welds were solid. The Welding Engineering
Standards
> > provided by Rohn state that....any cracks, blow holes or porosity must
be
> > removed. Since the tower did not meet those stated standards we had to
> > return it yesterday to the vendor and were given a full refund.
However,
> > we are still out $942.00 for the cost of the inspection. Now we are
> > searching for a tower in which we can be confident that it will pass a
> > radiographic weld inspection. >>
I'm working with them and I'm proposing a weld-less tower; i.e. an
erector set type like AB-105. But I don't know whether the weld testing was
necessary (sometimes building department personnel either don't know or won't
be practical with their interpretation) and I guess the bigger question is
"Are Rohn welds safe?". Historically hams have been aggressive with 45G and
55G tower loads with very few failures (that I know of). Generally the
failure is something other than the tower structure.
Cheers,
Steve K7LXC
TOWER TECH -
Professional tower work for ham radio
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