As far as power line stuff, lots of transmission lines get checked yearly.
Mostly by helicopter but some on the ground. The helicopter inspections
using visual, lidar, and infra red are getting very interesting, to the
point where they can find overheating splices and hardware before it fails.
They even xray some hardware on the live high voltage lines and do other
checks for damaged conductors with uv sensitive cameras. Even out here in
the sticks I regularly see the local inspector doing a visual check on the
distribution lines... Of course now that they can read the meters remotely
they can pay attention to checking the lines while the computer reads all
the meters they go by, kind of lets that guy do double duty.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://wiki.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://k1ttt.net
> -----Original Message-----
> From: Tom Kennedy [mailto:tvkennedy@i-zoom.net]
> Sent: Tuesday, August 30, 2011 20:09
> To: K8RI on TT; towertalk@contesting.com
> Subject: Re: [TowerTalk] yearly maintenance checks Re: Preforms
>
>
> When I do my checks on some 300 plus towers every year, which
> I originally
> installed I check them with a torque wrench and it is and
> will be a wonder
> to me if the nuts and bolts tighten even a little bit. A
> torque setting is
> a torque setting. Guy wires not checked guarantee a tower
> failure, high
> winds, ice or not. Failure to check a tower once a year will
> invalidate
> most commercial insurance on this side of the 49th. regards
> tom/va3tvk
> ----- Original Message -----
> From: "K8RI on TT" <k8ri-on-towertalk@tm.net>
> To: <towertalk@contesting.com>
> Sent: Tuesday, August 30, 2011 3:58 PM
> Subject: Re: [TowerTalk] yearly maintenance checks Re: Preforms
>
>
> > On 8/30/2011 9:14 AM, Jim Lux wrote:
> >> On 8/30/11 3:51 AM, Tom Kennedy wrote:
> >>> On any tower of any description a yearly maintenance
> check is a must, no
> >>> matter which system is being used. Towers that fail have
> been left with
> >>> out
> >>> said.
> >
> > Maybe so and maybe not. Ice storms have take down
> perfectly good tower
> > systems. So have high winds that were outside the norm for an area.
> >
> >>
> >> You know.. we see this advice all the time: "It's time for
> your annual
> >> spring tower check".. but I wonder.
> >
> > I see it as a good idea but it gives no guarantee.
> > And...how does the typical ham check a tower regularly.
> Remember that
> > every time you check the torque on bolts it tightens them
> just a tiny
> > bit more and if they have never seize on them the listed
> torque is going
> > to be way too much.
> > Guy line tension? that looks/feels about right, or a Loos gauge?
> > Elevated guy anchors Vs the standard approach?
> > is the tower still straight?
> >
> > I typically give it a good once over every couple of years
> and check the
> > guy tension by feel. If I find one that is obviously under
> tensioned or
> > the guy anchor post shows a definite lean (elevated guy anchors that
> > weigh 17,000# each) THEN I get out the Loos gauge.
> >
> >> There's an awful lot of power/telephone poles out there
> that I doubt get
> >> checked on an annual basis, and not a whole lot of them
> fail. Likewise
> >> light poles, freeway signs. Sure, if one breaks or gets obviously
> >> damaged, they go out and fix it, but is there some sort of
> organized "go
> >> check the poles and signs" activity?
> >
> > Now days? With money in short supply it took several years
> (more like
> > two decades) to get them to clear the right-of-way for the
> power line
> > through the woods. It's a mile run across the section to
> the sub station
> > and it's woods all the way. In general they do a cursory
> inspection. IE
> > if nothing is obviously broken they don't touch it. BTW 5
> years after
> > they cleared the right-of-way it's over grown to the point you can
> > hardly tell they ever cut it back.
> >
> >>
> >> And on big transmitting towers, I can see regular
> maintenance being part
> >> of the plan (you have to paint the darn thing and keep the lights
> >> working, for instance).
> >
> > And you can often pop the paint off the rust underneath. Comforting
> > thought at three or four hundred feet plus. <:-))
> > Plain steel wire rope guys an inch or more in diameter than
> ring like a
> > tuning fork when hit with a wrench. Boy, but those things
> can sing even
> > with that brown finish! <:-))
> >
> >> Likewise, if you have a crankup.. moving mechanical devices need
> >> periodic checks.
> >
> > Moving devices need to be moved periodically.
> >
> >
> >> Maybe it's because hams have a long history of improvisation and
> >> overloading (if the antenna didn't fall down in last
> winter's storms, it
> >> wasn't big enough) or it's from our agrarian heritage (the
> snow melts,
> >> time to get the plow out, curry the winter coat out of the
> draft horse,
> >> etc.)
> >>
> >> But, for instance, this thing about "checking the ground
> rod clamp"...
> >> the whole point of the clamp design is so that it
> shouldn't loosen with
> >> thermal cycling (i.e. does the electric company come out
> and check your
> >> grounding connection every year? Do you see recommendations that
> >> homeowners hire a licensed electrician annually?) And of
> course, one of
> >> the advantages of exothermic welding over clamps is that there's no
> >> possibility of it changing. Or is this, again, because
> hams have used
> >> all manner of improvised clamping schemes, and "design for
> immovability"
> >> wasn't necessarily in the list of requirements.
> >
> > I think "We may want to move that in a year or so" is the
> most likely
> > criteria although those split clamps are about a third the
> cost of "one
> > shots" might be the over riding criteria. <:-))
> >
> > 73
> >
> > Roger (K8RI)
> >
> > _______________________________________________
> >
> >
> >
> > _______________________________________________
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> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>
>
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