Repair work to headgear

[spanker]

Anyone know how often headgear wheels were changed and reason was it that they had come to the end of their working life,they were beginning to wobble, the bearings would begin to go ,there were cracks being detected (this would have been after the Markham disaster as we started to crack detect and look more in depth at the structures at that time) I remember regularly having to wait whilst crack detecting was being carried out as an apprentice.
During my 20 years at Ireland Colliery i remember this happening once, would this have been stipulated in the M&Q ACT I WILL HAVE TO GET IT OUT AND READ UP?
If i remember correctly the winding rope was changed frequently, oh and we had the odd cage changed in that time as well.

[John]

Sheave wheels are bound to wear out, no idea if they had inserts in them to replace or if the whole wheel needed to be replaced.
Even bearings fail after years of service, there must have been a lot of stress on deep shaft skip winding sheave wheels.
They seem to be an item that's almost out of site and forgotten by most folks, but at a guess they had to be examined and signed for daily by the Mechanical Engineering Staff.