Thread: Major engineering challenge

Then, I'm afraid... i would be standing around scratching my arse with everyone else. 2000ft is probably way too far for the conduit idea... i agree.

There must be a solution though... i refuse to accept that it can't be done at all. (getting the cable there... not the conduit thing)

If I was still with ABB i would ask some of the engineers what they have seen before... but, as it stands, the engineers i currently work with are a pack of halfwits who together couldnt raise a beer-fart in a whirlwind.

I'm spent mate... no more ideas... I've used up all i know about cables in holes

Greg Frazer

Well you got as good as we did in our first brain-storming session at work. Overall, I've got a lot of good stuff to discuss in the office tomorrow...
1) When I came up with the remote-controlled vehicle idea, it was scrapped but custom builds, tracks and leading lines didn't come into play.
2) The guy who suggested pvc piping is P-Eng certified with decades of experience in the mining industry.
3) Water-propelling did come into play but they weren't too gung-ho about it.
Today you gentlemen came up with some specifics and interesting elaborations that are more than worth looking at, so input from Alex will be golden.

You could experiment with a heavy plastic bag and an industrial vacuum. You could put the end of the cable in a strong 'garbage' bag, leaving just enough air in it to create a seal. You can then see if those industrial waste sucker trucks can reverse their suction and blow the inflated garbag bag down the hole. ???

Simplest solutions being the best: why not increase the width of the hole?

BTW I am not an engineer so if it is a really stupid solution I would say: have a good laugh at a layman's ignorance.

Adding to the crawler idea, consider that this is not an all or nothing proposition. You could, for example, use a commercial tension sensor on the line getting pulled into the hole. When is reaches some threshold below either when the cable would snap, or the crawler will lose forward motion capability, stop the crawler. Then, send a 2nd crawler in behind it to pull some of the slack laying in the hole closer to the first crawler. If the crawler itself is designed to crawl on the sides of the hole (horizontally), it may be able to be crawl over the guide wire. Granted, careful design needs to be considered so the line isn't caught in the second crawler, but it's feasible. Also, consider sending a 2nd DC power wire pair in with the first crawler, which it would pull along with the guide wire. Use a radio/solenoid actuator to allow it to be disconnected via radio. Then, use external DC power to get the unit as far into the hole as the DC wire can be pulled. Then, when that is too much, jettison the DC connection and go to the battery. As long as the DC voltage is just slightly higher than the battery float voltage, no energy will flow from the batteries, and they'll be starting from a full charge at that point, and not at the beginning of the 2000 foot run. - J

Check out using a high tech fiber like this.

OK, last idea, then back to bed (damn insomnia...).

How about flooding the hole, then using a buoyant powered torpedo device (same principles and ideas apply as with the crawler), to swim it's way through the hole. This alleviates much of the tension issue, since you can find a buoyant guide wire as well. At that point, you've mainly got surface tension from the liquid/wire interface, but even at 2000 feet, it could be insignificant compared to the thrust of the impeller.

night night - J

I thought about flooding the hole. then passing a very thin line attached to a floating ball, say ping pong ball. Then pump the water through, the ball will travel the length. Then you could pull through larger lines.
However I am not good at this sort of designing, so my idea is probably grossly flawed!!

I'm the idiot of the family, my brother is a genius so I will turn this over to him.

What I suggest is a two sided ball with air input on one side and air output on the other. Use flexible tubing to let the ball go into the now air deminished tunnel. Compressed air might be able to be used on the output side to push the ball further in.

Is the tunnel SEALED from air coming in??

I will call my brother. He is a plumber and is the plumber people call when they do not know how to do stuff, like solder with water still in the line.

If he can devise something is it worth flying him in and paying a consulting fee???

Jerry.

Well, it looks like neither one of us is in the office. Alex has a family emergency and I have bronchitis (just got the HD antibios to take care of it). Even though plumbing is still considered a viable solution, I want to run the tracked vehicle idea by him and discuss the options before taking the first attempt idea to the owner.

OK - how about this...


....visualize an umbrella---on the inside of the umbrella, up toward the peak, is a pulley with 4000' feet of cord fed half way through - 2000 feet sticking out each side of the pulley. Now, shrink the whole thing down to about twice the size of those little tiny umbrellas that Custommartini is putting in all those fruit drinks in Hawaii - and the cord shrinks down to that 250# test monofilament....OK, with me so far?


Now, put in one (or two) of those rocket cartridges that kids put in their model rockets - stuff the whole thing in the hole and touch it off - the folded umbrella/rocket goes screaming down the hole in a wondrous show of fire and smoke and impales itself on the end of the tunnel, still smoking and sputtering....a tug on BOTH ends of the monofil at the same time and the umbrella opens and the ends of the spindles impale themselves on the perimeter of the hole, providing a solid anchor point, so that when you attach your service cord to one end of the monofil, you've got a firm anchor with a pulley attached to pull against.

My only request is that I get to watch!

-whatever

-Lou