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Post by Wheldale on Nov 20, 2012 14:57:09 GMT -5
There was a post today about Boulby, mentioned the concrete headgear is shortly to be replaced. Is there a preference to concrete or steel headgears? I was told in South Africa that steel was used when it was cheap, then when the price of steel shot up concrete was used. Surely there must be more reasons that this?
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Post by John on Nov 20, 2012 15:53:05 GMT -5
Boulby has round concrete towers as against the fancy concrete headgear that the NCB was using.
There were some pits that had steel headgear that was over 100 years old, so says a lot for steel. As long as it's painted to protect it from corrosion, I'd say it would outlast concrete by many years.
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ken
Trainee
Posts: 46
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Post by ken on Nov 21, 2012 4:23:31 GMT -5
At Easington Colliery the foreman fitter did a headgear inspection and found a gap at the base of the of the columns where it entered the concrete foundation. It had been completely rusted out. Perhaps this had been caused by rainwater collecting there. I think it was fixed by pouring a bigger foundation. This happened about 1960 so the steel would have been about 50 years old. The column was constructed of four large angle irons with multiple cross bracings.
An unusual thing about this shaft - the downcast shaft which was brick lined, was that in the winter the shaft would shrink slightly and the shaft would leak. They fixed this by putting several large coke braziers around the shaft top before winter set in. A great place to get a warm in the winter!!
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