Sunday, 25 December 2011

Sedgeley Junction - Signalling Alterations 1964

The Dudley - Birmingham (Snow Hill) passenger service finished on Saturday June 13th 1964. Three weeks later, I did a morning shift at Sedgeley Junction on Saturday 4th July 1964. This was the last day of the Dudley - Walsall and Dudley - Dudley Port services. The timings are on pages 38 and 39 of Jan's Train Register Book.

I think it was that day I found copies of the drawings detailing the changes to be carried out to the interlocking at Sedgeley Junction box which were intended to 'single' the line to Dudley Port, retaining it as an Engineer's Siding. I hastily made my own sketches from the drawings.

I never returned to Sedgeley Junction so I don't know whether the planned alterations were introduced - on 20th September 1964 the box was destroyed in a fire. Certainly, alterations were made at Dudley Port, turning the branch into an Engineer's Siding. The changes at Dudley Port are described in the section titled 'Changes at Dudley Port Friday 2nd October 1964' in the post Traffic Movements on the Stour Valley, 1964

On Sunday 20th July 1964, Sedgeley Junction signal box was destroyed by fire and not re-instated. In the immediate aftermath, all the signals at Sedgeley Junction were maintained 'off' and the adjacent box at Horsley Fields was manned continuously to shorten the block section.

The four sketches I made are reproduced below. Click on any sketch for a larger view. These sketches not only show the alterations but give a good idea of the the situation in the previous period when I worked the signal box. For more information about L & NWR signal boxes and the 5.5 inch centres Tumbler Interlocking Frame fitted at Sedgeley Junction, refer to the excellent book 'A Pictorial Record of L.N.W.R. Signalling' by Richard D. Foster, published by Oxford Publishing Company in 1982 (SBN: 86093 147 1).

1. Title Page

This is a simplified sketch of the standard title sheet in use at the time. Note that the 40-lever frame is made up from two 15-lever girders and one 10-lever girder.

2. Locking Diagram showing Alterations

The book referred to above has a copy of an interlocking diagram dated 1878 which uses virtually identical symbology to this sketch. I'm afraid my hastily-made sketch isn't too clear. The vertical lines represent the Hook Racks operated by each lever which move in the Guide Rack. Horizontally, there are twelve channels for U-section Locking Bars. The symbol ' ][ ' indicates that two shorter Locking Bars share the same channel. Horizontal movement of the Locking Bars is effected by a Drive Stud attached to the Locking Bar operated from an 'L' shaped bell crank called the Actuator from the movement of the appropriate Hook Rack. Full or Half Locks attached to each Locking Bar allow or prevent movement of the Hook Racks attached to other levers as required by the desired interlocks. The whole Locking Rack is held together by a series of vertical Backbones which hold the Locking Bars and Hook Racks in position.

3. Locking Table showing Alterations

For each lever, this table tabulates what lever must be pulled before the lever in question can be pulled. The last three columns show which other levers are locked Normal, locked both Normal and Reverse and released by the lever in question.

4. Lever Colours, Pulls, Nameplates showing Alterations

This table shows which positions are working levers, spare (unused levers) or spaces (position where a lever could be fitted). The last three columns show, for each lever, the colour, the detail on the Pull Plate and the text on the Name Plate.