On Friday 23rd November, Eversholt Rail Group will complete the prototype installation of a Duplex Pantograph on a Class 91 locomotive. The installation project is a joint initiative between Eversholt Rail, East Coast, Brecknell–Willis, ESG and Wabtec Rail.
Eversholt Rail and East Coast identified that a Duplex Pantograph would eliminate a single point failure on the locomotive. This will reduce service failures and their impact on customers and Network Rail. A full analysis of the costs of in–service delays attributed to pantograph/OHLE system failures was carried out ahead of commissioning the project.
Brecknell–Willis were engaged to develop their well proven high speed pantograph design, using the same mounting positions as a conventional pantograph but pairing two conventional pantograph arms in an opposing configuration on the same base frame. This provides redundancy in the event of a pantograph system/OHLE failure but minimises the roof space required, compared to fitting an additional pantograph. The Duplex Pantograph incorporates the latest developments including Fast Automatic Dropping Device, chain guards pan housed indication and bonded ceramic carbons.
The Duplex Pantograph design to be used in the prototype was developed following substantial research and analysis. Eversholt Rail selected ESG as its installation designer and project manager. The complexity of the installation design means the fitting of a prototype locomotive is necessary before any fleet roll–out will be considered. The original GRP roof canopy had to be replaced with a flat roof and new profile canopy. ESG carried out an ergonomic assessment of the number two cab to consider access to and egress from the loco, a new lighting arrangement and cab air–conditioning requirements. ESG also designed a new control system, to satisfy Eversholt Rail and East Coast’s functional specification. Existing driving controls are unchanged and an ethernet–based monitoring system shows the status of the Duplex Pantograph in both locomotive cabs, plus the cab of the Driving Van Trailer.
In addition, a test strategy has been developed to de–risk key elements of the design and allow East Coast to show compatibility between the modified locomotive and the existing infrastructure. This strategy includes high voltage testing of the new installation and in–service tests monitoring pantograph performance and uplift.
The project will be completed in 54 weeks, within the allocated budget and timescale. Installation is taking place at Wabtec Rail in Doncaster, following the planned overhaul of locomotive 91114.