Sutton Bridge Junction Signal Box

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See also Sutton Bridge Junction.

Sutton Bridge Junction Signal Box is a still open signal box on Network Rail located approximately 2/3 of a mile south of Shrewsbury station, which controls Sutton Bridge Junction, and originally the Severn Valley's junction with the mainline at Shrewsbury. It still controls the junction between the Shrewsbury & Hereford line and the Cambrian line to Machynlleth, Aberystwyth and Pwllheli, and access to Coleham yard. It also has an UpIn reference to the direction of travel means towards the major terminus (i.e. towards Kidderminster on the present day SVR) goods loop, which is the truncated 'UpIn reference to the direction of travel means towards the major terminus (i.e. towards Kidderminster on the present day SVR) Avoiding' goods only line which originally ran from Bayston Hill signal box to the south (now closed). The UpIn reference to the direction of travel means towards the major terminus (i.e. towards Kidderminster on the present day SVR) direction is towards Shrewsbury for the Cambrian and Hereford lines, whilst UpIn reference to the direction of travel means towards the major terminus (i.e. towards Kidderminster on the present day SVR) was to the south on the Severn Valley line.

The box was built in 1913 to replace earlier signalling installations at the junction, and is built to conventional GW style of the time all in brick, although because of its location in connection with the Severn Valley line it has full height windows on the operating floor around the whole northern end. Originally, it had a nameplate mounted on both the front and rear, to allow it to be identified from all lines, but the one on the rear's whereabouts is currently unknown. It has a 61 lever 3-bar vertical tappet frame which is original to the box and is therefore of the same vintage. Three of the levers retain brass lever leadsThe (usually brass) information panel on a point or signal lever informing the signalman which other levers need to be pulled to release that lever (the plate indicating the lever's purpose and what levers must be reversed to enable it to be worked), whilst the others all have the later rectangular traffolite style. Interestingly, the original lever leadsThe (usually brass) information panel on a point or signal lever informing the signalman which other levers need to be pulled to release that lever related to the Severn Valley line referred to 'To' or 'From' Worcester, for example 'From Worcester Safety' for a lever which worked a trap point for any runaway train coming from Berrington.

The box is built on the eastern side of the Shrewsbury & Hereford line (sometimes referred to as the North & West), and originally the SVRSevern Valley Railway joined this line immediately to the north of the box, coming in from the southeast. The junction and where the line passed under a road bridge can still be readily seen. Until 1988, a stub of the Severn Valley line remained in use, providing via a reverse move access to the site of Shrewsbury Abbey station (Shropshire & Montgomeryshire Light Railway), which remained in use as a fuel terminal.

In the 1960s the Shrewsbury & Hereford line came under the control of the London Midland Region (LMR) of British Railways as far south as Craven Arms, meaning the GWRGreat Western Railway design box and frame underwent some notable changes. It now has standard BRBritish Rail or British Railways bakelite block instruments, a LMR style block shelf - which bears LMR style lamp and arm indicators and the modern diagram - and electric lock releases actuated by catch handles on most electrically locked levers, rather than the GWRGreat Western Railway/BRBritish Rail or British Railways(W) style block shelf plunger.

The layout of the junction has been extensively remodelled since the late 1960s/70s which has caused many levers to change use. This means for example that lever 5, which was originally the inner home signal reading off the Severn Valley line, is now the UpIn reference to the direction of travel means towards the major terminus (i.e. towards Kidderminster on the present day SVR) starting signal and therefore in continuous use.

Signalling diagram

Signalling controlled from the box

As part of the significant redesign of the layout at Sutton Bridge, many of the original GWRGreat Western Railway/BRBritish Rail or British Railways(W) design signals were replaced with standard BRBritish Rail or British Railways(LMR) upper quadrant signals, unusually resulting in a GWRGreat Western Railway box controlling LMSLondon Midland & Scottish Railway style signals. The UpIn reference to the direction of travel means towards the major terminus (i.e. towards Kidderminster on the present day SVR) inner home on the Cambrian branch and the DownIn reference to the direction of travel means away from the major terminus (i.e. towards Bridgnorth on the present day SVR) home bracket remain GWRGreat Western Railway/BRBritish Rail or British Railways(W) lower quadrant design however. On the latter, the space can be made out that originally controlled the junction onto the Severn Valley line. The box also controls colour light signals in the form of its UpIn reference to the direction of travel means towards the major terminus (i.e. towards Kidderminster on the present day SVR) distant signals on both the Hereford and Cambrian lines, and the UpIn reference to the direction of travel means towards the major terminus (i.e. towards Kidderminster on the present day SVR) home on the Hereford line is a 3-position colour light, which only shows green when the UpIn reference to the direction of travel means towards the major terminus (i.e. towards Kidderminster on the present day SVR) inner home and starting signals are cleared. It will show a yellow when reversed, only once the home berth track circuit immediately in rear of it has occupied, effectively checking the train down to a low speed in accordance with what was (and still is on the SVRSevern Valley Railway) Rule 39(a).

The box works to Absolute Block regulations to the north and south, working to Severn Bridge Junction to the north and Dorrington to the south (and Marshbrook when Dorrington is switched out). It works to Machynlleth Signalling Centre under Track Circuit Block regulations as far as the commencement of Cab signalling board on the Cambrian, beyond which the in-cab signalling system European Rail Traffic Management System (ERTMS) comes into effect. Controls on communication between Sutton Bridge and Machynlleth are mounted on the diagram. Originally the box worked by Absolute Block to the now closed Coleham and Bayston Hill boxes to the north and south respectively, to Hookagate signal box towards Machynlleth, and to Burnt Mill Junction box on the Severn Valley Line. However, this box closed in 1937 and communication was then by Electric Train Token to Berrington signal box.

See Also