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Utility poles

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Re: Utility poles

#11

Post by Slansitartop »

zwieback wrote: post #7
pan69 wrote: post #6

I have always wondered about utility poles, they always seem very fragile. Why not just stick everything in the ground?

I think it's cost, mainly. Also, in my neighborhood of older homes it would be hard to get all the easements. http://www.elp.com/articles/powergrid_international/print/vo...

Also maintenance and access. I once had an underground power line to my apartment building fail, and it took the better part of the day for them to repair it. They had to tear up the parking lot in the process.

Re: Utility poles

#12

Post by joeframbach »

sevensor wrote: post #9
joeframbach wrote: post #3

Old utility poles can be reused in many ways too, but they must be outdoors, and not where it can have direct contact with people. Back in 2003 I called a local electric company if they could donate a few used poles to be used as beams for a bridge I was constructing for a local park. They we're happy to oblige. You can sometimes see these poles used in retaining walls and buried alongside hiking trails, used as wate…

> and not where it can have direct contact with people. Could you expand on that? My elementary school had a playground structure made of old utility poles. Other than getting pitch on our clothes, they didn't seem particularly hazardous.

I'm not an expert, but I can guess it depends on the pole and how it's been treated. The company I called gave me a list of disclosures and guidelines for re-use. Maybe the poles you see haven't been treated with such-and-such chemicals.

Re: Utility poles

#13

Post by emilecantin »

pan69 wrote: post #6

I have always wondered about utility poles, they always seem very fragile. Why not just stick everything in the ground?

An individual pole is relatively fragile indeed, but they're stringed together with steel cables, so the whole assembly is pretty solid.

Source: Worked as a phone technician a while ago, climbed in these poles for a living. I hated climbing in "service poles" (individual poles not connected to the steel cable, used in cases where a house is far from the street), they'd wobble like crazy.

Re: Utility poles

#14

Post by jmspring »

sevensor wrote: post #9
joeframbach wrote: post #3

Old utility poles can be reused in many ways too, but they must be outdoors, and not where it can have direct contact with people. Back in 2003 I called a local electric company if they could donate a few used poles to be used as beams for a bridge I was constructing for a local park. They we're happy to oblige. You can sometimes see these poles used in retaining walls and buried alongside hiking trails, used as wate…

> and not where it can have direct contact with people. Could you expand on that? My elementary school had a playground structure made of old utility poles. Other than getting pitch on our clothes, they didn't seem particularly hazardous.

Like pressure treated lumber, the chemicals used to make the poles less susceptible to bugs/rot/etc can be hazardous to people. Until a few years ago, arsenic was one of the components used -- in commercially available pressure treated lumber. I suspect the same chemical cocktail has been used in poles.

(edit -- add commercially available lumber clarification)

Re: Utility poles

#15

Post by Dangeranger »

Back around 2010 I worked for a company which built software to catalog residential distribution utility poles and the lines emanating from the poles to the houses.

To elaborate on a few of the statements from the post

    Poles in my neighborhood tend to have consecutive numbers. I don't think this was carefully planned.
The sequential ordering of pole numbers is definitely planned, and fits in with a scheme developed back in the 60s-70s which made documenting the poles lifecycle in paper records much easier. The poles are numbered sequentially with prefix numbers generally indicating which substation district the pole belongs within. Distribution utilities think about their infrastructure as a network of substation circuits. You should be able to tell which circuit you are on based on the numbering on the pole.

    There are three because that is one way to change the three-phase power to single-phase, something I wish I understood better. Truly, we live in an age of marvels.
Not all distribution systems use three phases, some use two, some use single. It all depends on where you are in the system and the general layout of the circuits within the distribution network. Also not all distribution is 7kV, some are 12kV, and some are 25kV. Again this all changes based on the properties of the system, and the qualities that are being optimized for by the power engineers.

     I have tried to imagine what the number-burning device looks like, but I'm not at all sure. Is it like a heated printing press, or perhaps a sort of configurable branding iron?
This can be done a number of different ways, but one of the common ways is with a laser engraver. This is a fairly recent practice, so I am not as versed in the operational details as with traditional tagging. Another means of tagging which is not covered in the article is carving the numbers into the pole with a physical etcher, similar to a wood router.

    Without the Internet I would just have to wonder what these were and what OSMOSE meant.
OSMOSE was at the time of my work in this field, the largest such company that dealt in the support and maintenance of residential utility poles. They have some very interesting proprietary mechanisms for managing inventories, and are generally a very smart group of people. My guess is that they collect all the inventory and survey maintenance of poles using mobile LiDAR and machine vision now, as that was what we were speaking to them about at the time.

Re: Utility poles

#16

Post by ranger207 »

sevensor wrote: post #9
joeframbach wrote: post #3

Old utility poles can be reused in many ways too, but they must be outdoors, and not where it can have direct contact with people. Back in 2003 I called a local electric company if they could donate a few used poles to be used as beams for a bridge I was constructing for a local park. They we're happy to oblige. You can sometimes see these poles used in retaining walls and buried alongside hiking trails, used as wate…

> and not where it can have direct contact with people. Could you expand on that? My elementary school had a playground structure made of old utility poles. Other than getting pitch on our clothes, they didn't seem particularly hazardous.

They're treated with lots of preservatives. They're probably not all that dangerous in the short term (unless you eat some of the pitch), but it's annoying to deal with the potential long term safety. My scoutmaster worked for the power company, and I was going to ask him if we could have a couple of poles for my Eagle project, but after looking at what you had to do to reuse them I decided it was simply too much of a hassle.

Re: Utility poles

#17

Post by jmspring »

Dangeranger wrote: post #15

Back around 2010 I worked for a company which built software to catalog residential distribution utility poles and the lines emanating from the poles to the houses. To elaborate on a few of the statements from the post Poles in my neighborhood tend to have consecutive numbers. I don't think this was carefully planned. The sequential ordering of pole numbers is definitely planned, and fits in with a scheme developed b…

The pole numbering also helps in things like the work PG&E has to do checking for trees and other obstacles posing a risk to transmission lines. The report indicating where the work needs to be done (for instance to cut down a tree) uses the pole number as a point of reference.

Re: Utility poles

#19

Post by gilbetron »

My dad was an electrician for about 40 years - one story he told me when he was training apprentices years ago was teaching them how to climb telephone polls. You wore boots that had spikes in the side of them, but when climbing, you had to keep your knees away from the poll so the spikes would dig in properly. Unfortunately, when you get to the top of the pole and look down, some people panic due to the height. And when they panic, they tend to "hug" the poll, which causes the spikes to pull out, which causes the person to slide down the poll which is pretty much a collection of splinters in poll form. They called it "burning the poll".

Re: Utility poles

#20

Post by Dangeranger »

pan69 wrote: post #6

I have always wondered about utility poles, they always seem very fragile. Why not just stick everything in the ground?

It is an order of magnitude more expensive to bury utility lines under ground, both in upfront costs and ongoing maintenance costs. This is due to the safety that has to be put in place to protect the wires, and the people who may dig into the wires while they are underground. Additionally making alterations to a power system due to a growing or changing residential power needs is much harder to do and takes longer when the power is routed under ground.
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