Wednesday, 7 January 2009

Wed 7th Jan

Evenin' all,

Well, what a lot of interest about 'breathers'. Between Idridgehay and
Shottle, we have about one and a half miles of continuously welded rail
-well it will be in due course. Rail expands and contracts with
heat/cold. On jointed track of 60', the expansion is taken up at the
rail joints which expand or contract only a small amount. Over 1.5
miles this movement can be quite large. To conpensate for this movement
at either end we have breather switches aka expansion gapd, where the
rails are cut along the last 18" or so lengthways, one rail is fixed
and the one attached to the CWR slides back and forth to take account
iof rail movement. Our rails have not been serviced for many years and
had seized up fully tight. The best way to open the gap is to unclip
the cwr on a really cold day so that the rail contracts, as it does so,
it breaks the rust seal, which is what occured. The ends are then
covered in grease including all fishing surfaces. When the rails heat
up, the gap will close again. If there was no movement the rail would
still expoand in hot weather, but instead of the rail getting longer,
it would bow outwards and the track would spread.
This treatment allows for natural expansion over the last 130 meters
only, at either end, the remaining rail between the two ends can then
either have a natural stress (rail temperature 27 - 34 degrees) or can
be machine stressed. This will be done once welding has been completed.

We had planned to do the Shottle end today but the temperature rose to
a balmy 5 degrees. As that end is on the downhill end of the CWR it
would have to have been pulled back further to open the gap, as owing
to some rail creap extra pressure has been put on the breather, this
will have to wait for another day.

However, other work was carried out at Shottle including the creation
of a temporary roadway in the yard to allow the spoil mountain to be
moved, the RRAP had more stone dropped on it to allow road/rail
vehicles to on and off track easier., sleepers were moved as were
concrete fence posts and bags of clips/pads etc. More logs were
collected on the return trip.

Some visitors were given the grand tour, which may lead to new
business.

A number of visitors arrived for a look around and spent a couple of
bob in the Booking Hall. More log cutting and sales. Pat Craft spent
most of the day carrying out a sortout and stocktake.

Phil

50% off Norton Security 2009 - http://www.tiscali.co.uk/security

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