Wessex Signal Post Renewals

The challenge

Following a report that signals at both Dorchester South and New Malden were leaning away from the track, subsequent examinations of the structures’ foundations found evidence of crumbling and subsidence. As a result, these two signals (namely DR165 and W210) were scheduled for replacement to alleviate a pressing infrastructure safety issue.

The solution

Following a competitive tender process, Network Rail Wessex Works Delivery instructed Amaro to carry out the necessary design, procurement, installation, and testing of the following two signals:

• DR165R – A right-hand mounted 2-aspect filament signal at Dorchester South on the BML2 ELR
• W210 – A left-hand mounted 4-aspect Westinghouse filament signal on the Up Kingston at New Malden

… installing updated signal posts and replacing the end-of-life filament signals with cutting-edge Dorman LED units.

During a single 52-hour possession in April 2024, an Amaro team supported by a number of third-party organisations completed all works within 5 separate shifts, averaging approximately 9 hours per shift.

Shift one saw traffic management established, followed by the preparation and marking up of a number of screw pile hole locations, required to anchor the new signal posts securely in place.

With the RRV arriving at the work site towards the end of the first shift, the following shift focused on the installation of the screw piles themselves with shift three seeing the establishment of a new platform and hardstanding around the signal base, not to mention a modern GRP walkway and handrails.

With the preparatory works now complete, shift four saw the piling works finalised, followed by the installation of a lightweight, fold-down signal post and an upgraded LED signal unit. Along with all associated cabling, the location case was prepared ready for changeover before the now-redundant signal was recovered safely using the RRV.

During our final shift on site, a 6-strong team returned to Dorchester South to carry out pre-testing, performing a controlled changeover of cable before the new signal was sighted, tested and returned back to the signaller.

All works were carried out in accordance with W210 Signal Sighting Form (Appendix A) and the Wessex Signalling Equipment Policy NR/RAM/WSX/2014/001 v5 (Appendix C).

The outcome