Engineering trains get a refit

Posted: 2 August 2010 | Freestyle Marketing Communications | No comments yet

Tubeline’s fleet of 29 Electric Engineering Locomotives are getting a refit. The team responsible, decided to stick with trusted vented lead acid batteries, new production techniques and cell design…

Tube Lines

Tubeline’s fleet of 29 Electric Engineering Locomotives are getting a refit. Although the team responsible for the redesign decided to stick with trusted vented lead acid batteries, new production techniques and cell design has allowed for a number of improvements – particularly in cab size, battery installation procedures and safety.

Tube LinesA “prototype” locomotive, designation “L24”, currently undergoing commissioning and evaluation trials, has had 168 lead acid cells, to the new design installed, using the new efficient and safer method. The locomotive has also had the driving cab layout improved ergonomically, new equipment fitted, LED lighting and cab access and egress improved.

The trains are used to support engineering work, ranging from day to day infrastructure maintenance, through to major track renewal & system improvements across the entire surface and deep tube London Underground network. The locomotives have been specifically designed to have dual traction power capability. This enables Engineers Trains to travel to and from worksites utilising 3rd & 4th rail electric traction current during “traffic hours”, when passenger trains are operating and by switching to battery power during “engineering hours”, when passenger trains stop running and traction current is switched off. The battery power comes from the 168 lead acid cells fitted within the locomotive. The battery cell design and layout has remained essentially unchanged since originally first supplied and installed in the 1960’s. As well as providing traction power for the locomotives, the batteries also power on-board equipment and lighting as well as wagon mounted equipment.

Aside from the opportunity to improve the cab space and ergonomic layout, the taller, narrower cells and layout have allowed the battery cells to be installed from the outside of the locomotive via removable panels – enabling the cells to be lifted into position by a forklift truck, in banks of 12 at a time. Previously each cell had to be installed individually by hand and lifted into position by 2 men from inside the loco. Therefore not only has the installation and removal of cells become easier and quicker, but more importantly it has reduced the handling risks associated with the installation making the whole process from delivery to installation far safer for all the staff involved. Previously, it would take 8 engineers 2 days to change the batteries manually, with the aid of rollers. Now, it takes 2 engineers 2 hours 20 mins with a forklift. This means that the batteries can be changed any time, not just at weekends.

The improvements in cell design, layout and installation have been developed by Exide Technologies, along with Transplant, the Tubelines department responsible for both maintaining and operating the Locomotive fleet. John Harris, Maintenance Manager was responsible for re-designing the cells and worked closely with the team at Exide. John comments, “A number of alternative power solutions were investigated; Nickel cadmium was discounted because twice the number of cells to obtain the same output would have been required – so space and maximum weight issues would have been a problem. Additionally, the ‘memory effect’ would not have suited the running/charging regime. Fuel cells would have posed storage and installation issues. Vented Lead Acid technology was proven, suited our working methods/times and was familiar technology to the staff. The new design should be delivering benefits for decades to come.”