Monday, July 20, 2009
1905 - 1910 The building of Ragged Chutes
Ragged Chutes was Charles most ambitious project and his greatest success. The feeder shaft, 351 feet deep and 9 and 1/2 feet in diameter was sunk into the bedrock. The lower 40 feet widens to 11 and 1/2 feet in diameter. At the top of this shaft are twin intake heads each containing 72 intake pipes, 16 inches in diameter.
Water backed up behind the 660 foot wide dam swirls down through these pipes carrying air with it. When the water reaches the bottom of the shaft, it is diverterted into a 1021 foot long horizontal tunnel by a steel sheathed concrete cone.
This tunnel is 20 feet wide and 26 feet high, at the far end a bulge in the ceiling increases the height to 42 feet. The rushing water slows down in this tunnel and the air collects along the roof at approximately 120 p.s.i. A 298 foot tail shaft by 22 feet in diameter returns the water to the surface. Once at the surface it continues down the Montreal River.
The air, under pressure, in the pocket below ground is tapped off by a 24 inch diameter steel pipe and brought to the surface. Here it passes into a valve house and is distributed to the mines of Cobalt.
The air is transported to the mines via a seamless pipe, imported from Germany, specific to this project. There is a total of 21 miles of seamless pipe used for the movement of air to the various mines.
(The photo at the right is of shaft #8 it has a pencil sketch on the back presumably by Charles Taylor that was done on site.)
When more compressed air, than can be used, builds up in the chamber the water level in the tunnel is forced down exposing the end of a 12 inch release pipe. The excess air blows out 10 feet below the surface of the Montreal River resulting in a geyser plume that often reaches 200 feet in the air. It was one of the most impressive site around Cobalt during the hayday of the Air Plant.
To reduce friction and drag in the intake and tail shaft Taylor had to devise a method of drilling in the granite that would ensure a smooth vertical wall. He designed a drilling rig that allowed the men to work from a wooden platform that rotated on a central axis, thus maintaining a constant diameter. Wall fractures in the granite substrate were smoothed with cement to eliminate uneven surfaces.
There were many nay sayers at the time who did not believe Taylors calculations, there were many in the Engineering field that said it could not be done. The general feeling around Cobalt at the time was, "Taylor is crazy, a two bit, so-called engineer, self taught, little better than a mechanic with a bunch of wacky ideas". He was this and more, most visionaries are. The educated and informed doubt the abilities of those without the paper qualification however Taylor not only proved them wrong but his Air Plant was so finely engineered that it operated unabated, but for two maintenance shutdowns, up until fire destroyed it in the 1980's.
( special thanks for the text, in part, to Richard Hillary grandson of CH Taylor).