Greatest Achievement in Engineering II

[unclesyd]

This is an addition to zdas04's post of similar name.

Having just come through a major hurricane and old enough to have witnessed many recovery efforts by the electrical, telephone, and now cable systems I have to nominate the “Cherry Picker” or “Articulated Arm Boom Truck” as one of the top engineering developments of recent years. This is an achievement of several disciplines, mechanical, materials, and control systems. Have seen the restoration work done by hand and brute force it is truly amazing what can be done by 4 men and two boom trucks. One trucks digs the hole and drops in a pole with the hardware in a few minutes where as I’ve seen it take a half a day to get a hole dug, by hand, sometimes dynamite, and 10 to 15 men with pike poles to set the pole up. The only carry over I saw use is the “Cant Hook” used to align the pole after it is in the hole. The guys in the wire truck with boom work with amazing speed where at one time it took two men up the pole on spikes to bolt on the hardware and two on each adjacent pole to string the wire. I had my power back in 72 hrs which included the replacement of 26 poles in a mile and a half.

Another thing is the resilience of the fiber optic cable used by the cable company. It was down every where and it appears that it was just picked and rehung on the new poles like nothing had happened. I got cable back 48 hrs after the power was restored.

 

[DrillerNic]

Uncles- Interesting!

But- wouldn't it make more sense to bury these utility lines in places that are prone to major storms like hurricanes?

 

[SlideRuleEra]

DrillerNic - I live in "hurricane county" too, and worked for an electric utility for many years; the big issues for underground lines are cost and safety. The 240 volt service for new residences is often buried. When you are talking about distibution lines at 12,000 volts (or so) it becomes a problem making sure that the conductors are adequately insulated and protected from the public (Have Shovel - Will Dig).

 

[rerig]

Yeah, but I'll bet they only dig there once!

 

[IRstuff]

once per each owner, perhaps ;-)

TTFN

 

[JDana]

Always call before you dig!

In Ohio it's the law. Most (All?) other states as well.

Sorry, my wife works at Ohio Utilities Protection Service so I hear it all the time.

 

[unclesyd]

Over the years there has been considerable talk about an underground electrical distribution system in this area but it has always came to naught. I suspect it will be discussed again post mortem. I attended several meeting after Erin an Opal hit the area where the biggest argument against was the sprawl of this area. There were many other considerations concerning the high tension wires underground as posted by SlideRuleEra. One thing they have done is raise the elevation of the distribution lines to prevent tree damage. The only problem is a lot of these poles broke into several pieces under load. It looks like the treatment used may have caused the poles to be very brittle, I had never seen a pole in 3 or 4 pieces before. A lot of the electrical distribution system came down due to the load imposed by the telephone and cable lines catching a tree.
We have to be like a garden spider I have in the back yard make a few temporary repairs and the work on rebuilding a more permanent structure.

 

[ScottyUK]

In the UK most of the MV urban network is a buried service, as is some of the HV network. It has been this way for many years. We don't have a large number of incidents caused by over-enthusiastic navvies finding the cable with a spade or a back-hoe. Are the utilities - both UK and US - perhaps guilty of staying with a technology they are familiar with?




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If we learn from our mistakes,
I'm getting a great education!

 

[DrillerNic]

One of my first summer jobs at univeristy was putting a continuous plastic strip with "GAS PIPELINE - STOP DIGGING" written on it during the backfilling 1m above a HP gas pipeline, and then the backfilling continued....

Easiest job I ever had in construction!

 

[pba]

I have worked on two projects here in the UK where underground MV cables have been damaged. On both occasions this occured after the cable had been located and exposed. Both were down to stupidity on the part of the groundworkers. I don't mean any offence but I'd guess that American and Canadian groundworkers are just as stupid.

 

[ivymike]

here in IL they have a "call before you dig" law too. Unfortunately, when I was putting in my fence, the utility only marked SOME of the lines after I called. A month after the fence went up, the power went out at the neigbors' house due to a damaged line. The power company sent me a bill for $2700, and a reminder to "call before you dig." It was very difficult to convince them that they were at fault - they really weren't interested in the facts surrounding the matter. Then I discovered that there was a state regulatory commision responsible for investigating violations of the "call before you dig" law, and an investigator from the state got a much more reasonable response from the power company than I'd been getting. A few days after I submitted my complaint to the state, I got cc'd on a letter that the investigator had sent to the utility; two weeks later the utility called back to say that they'd be writing off the loss and not pursuing any further action against me (no "sorry for almost killing you," though). That reminds me - I should write to the investigator and find out what the results of the investigation were (potential $5k fine for the utility).