Saturday 29th April 2017

Just in case you may think that work on the track and signalling system has stopped for the summer while trains are running, may I correct that impression. Naturally the scope of the works change with normal routine inspection and maintenance taking over. As I have said in previous diaries, we patrol all the Running Lines once a week throughout the operating period so we know exactly what the condition is and where we may have to do some repair work. 

On the track, for example, Norman is working his way round all the facing point switches and checking them for compliance with Technical Standard 053 as I referred to last time where we had to grind some of the switch blades back into profile at Goathland slip under bridge 26.  Standard 053 was originally created by the London Midland Region of British Rail to help ensure that switch blades met certain, very prescriptive dimensions. It has been updated several times since and is still the definitive measure of switches from the P Way point(!) of view.  Coupled with the various regular testing with S&T gauges, we aim to minimise the risks of a derailment at switches. One turnout done recently was 2A points at Pickering. This leads from platform 2 line into Carriage & Wagon but is also used by passenger trains and locos running round passenger trains in platform 1. Part of the checks includes the condition of the rest of the turnout including the timbers and crossing. We have been concerned about the general condition of the turnouts in Pickering as they are curved and are on a poor ash and other “stuff” formation with dipped joints.   

We have now carried out a detailed inspection of these turnouts and are doing some maintenance to prolong their useful working lives.  Much of this work is traditional track maintenance that used to be carried out by hand, which of course is a long lost art on the national railway system!  In photo A you can see Pete and Mick (rear view only!) replacing a chair with Darren about to drop the jack hopefully after they have taken their fingers out!

In photo B you can see the broken “D” chair now replaced by another complete one from our stocks in New Bridge. In case you are interested and even if not, I am still going to explain that the chairs in bullhead common or normal crossings are each unique to a particular place.  The one under the crossing nose is an “A”, the next away from the switches is a “B” and so on. The ones on the other side towards the switches are “X” then “Y” etc. But they also have to fit the angle of the crossing so they are also identified as say “10A”, “10B” etc. And, the angle of the crossing itself is measured on centre-line measure!

 

In view C, Darren and Mick are replacing the old wooden ferrules with new pretty yellow plastic ones. Having good ferrules for the chair screws helps ensure that the chairs are securely held in position thus maintaining the gauge. The standard gauges is 1435mm (or the old 4ft - 8½ inches) but we would normally have some gauge widening on the sharper curves of say another 5 to 10mm. The gauge where they are replacing the ferrules measured 1445mm. Just beyond here there a number of very poor timbers so we will be changing these shortly which will help bring the gauge back into tolerance. These timbers are actually interlaced sleepers which was an old way of timbering turnouts. This helps in changing them as there is just enough space in the six-foot alongside platform 1 track to swing them around to get them out. This is all hand work which will have to be done in between trains. We will also be tightening up screws with new ferrules in 5 Points as some of the chairs are shuffling a bit that leads to wide gauge if not corrected.

Elsewhere we are selling off the old sleepers, rails and other surplus items mostly for scrap and to make room for the next lots of track materials for next winter’s relaying programme. One section we need to relay is between bridges 12 and 13 at the southern end of Levisham straight near Farworth where the wooden sleepers are of concern. In deepest Newtondale this section is shown in D. This relay will use the steel sleepers we have in stock as there is almost enough stone ballast on site. For steel sleepers we either have to use wooden sleepers at the joints or weld the rails so we will have another section of Continuous Welded Rail (CWR) track. This will have one set of adjustment switches just north of bridge 12 and the other just south of bridge 13. When we replace the waybeam bridge decks with ballasted track and relay back to Kingthorpe and north towards Levisham in years to come, these breathers will simply be moved along, so nothing is wasted.

 

Some people have asked about steel sleepers in the UK. They were originally invented for use in Africa and elsewhere that had termites chomping away at the traditional wood sleepers. When I was doing some audits on the big railway some years ago I came across some steel sleepers with GWR chairs welded on when doing a track inspection near Dovey Junction in mid–Wales so they have been used for a long time in the UK. In more recent times, far better designs have been used on the national network. These have spade ends to help stop any lateral movements and pressed housings for the rail fastenings as seen in E. To be safely used they have to have the ballast tamped up and into the undersides as well as around the spade ends as it is almost impossible to do this by hand. One significant advantage is that they can work successfully with smaller depths of ballast, which is what we have at Farworth.

All for now,

Regards
Nigel Trotter
NYMR Civil Engineer

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