Elevators
Grain dust is one of the most explosive dusts in existence. As you can probably speculate, wiring in a grain elevator is very particular, in more ways than one. You have to be very particular about the materials and manner of wiring, and you have to work in an area of particulates. One spark could blow the elevator to smithereens. (I’ve always wondered where Smithereens are located.)
Grain elevators are not replaced very often. They are built to last for many years. One of the more common methods of building grain elevators is to lay 2×6 boards flat on top of one another and nail them together. Other elevators may be constructed of poured cement. As a result of the longevity of grain elevators, some of them are very old and do not have modern equipment, design or wiring.
One of the jobs I was given in Montana required me to rewire an old wooden elevator. I had to use special, extra tough, wire and seal-offs. These are materials commonly used in gasoline pumps, propane pumps and some manufacturing plants. They are collectively referred to as “explosion proof” materials.
To get to the top of the grain elevator, I had to use a “man” elevator. Well actually it was a little platform about 2 feet square that operated by a rope and pulley system. The rope was run through a series of pulleys and allowed me to hoist myself to the top. Coming down, I had to pull on a different rope, similar to some window shades. There are times I still dream of riding that open elevator.
Now a passenger elevator in a multi-storied building is different. They have the mechanism for running the elevator on the roof in a small building called a penthouse. An older elevator will have cables, pulleys, contacts and controls. I worked on an older one that needed regular repair work.
I would step inside the little penthouse and it was a cacophony of sound. There were snaps, clicks, bangs and sparks flying everywhere. I could see signs of a fire having burned inside the penthouse, but since it was built out of a non-flammable material, the fire had gone out.
I had to replace the points on a number of contacts. It required that the elevator be shut down. That was very inconvenient for everyone.
Now the newer elevators will have a long hydraulic shaft buried deep in the ground under the elevator housing area. Usually these are a type of telescoping shaft. They run much smoother and quieter than the older ones, without the need of a penthouse.
There are times I am utterly astounded at all of the equipment that is used to get us through an ordinary day.