In a message dated 2/28/2003 6:17:29 AM Central Standard Time,
[log in to unmask] writes:
> I was interested to note that Robin's Shaft Mine in Staffordshire has an
> entrance / hauling shaft inclined at roughly 45 degrees, apparently in a
> similar fashion to Cornish mining techniques.
>
> Can anyone suggest why this was done, and what are the benefits / reasons
> for inclining a shaft, as presumably this would make hauling difficult and
> require a tramway or other means of transport?
>
Hello Jim,
In hard rock mines, shafts sunk today are almost always vertical. As a rule
of thumb,inclined shafts are employed when the ore body dips at less than 60
degrees from the horizontal. It also boils down to development and operating
costs. It is a rather detailed subject which can be explained in detail in a
good mining engineering text having to do with mine development and
equipment.
I do know that the Cornishmen in America despised the vertical shaft whenever
they were being transpoted in a bucket ( kibble ). They never trusted the
wire rope from which they were suspended. I guess it would be a bit unnerving
after using a man engine or a ladder to get up to grass.That changed with the
introduction of the man cage, running on wooden guides and the use of the
safety dogs to grab onto the guides in the event of a wire rope break.
Jim Besleme
Columbia, Missouri
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