Rethinking the basics on track renewals - LU needs your help

Jackie Whitelaw talks to infrastructure programme director George McInulty about the new ideas that are speeding up one of the toughest tasks on the capital’s metro railway. And it needs to tap into the brains of the supply chain for more.

Uxbridge blockade - this summer's big activity with 6km of life expired track replaced.

“My favourite fact,” says George McInulty, London Underground’s infrastructure programme director, responsible for its Track Partnership, “is that in the first three weekends of this year we delivered 50% of the total volume of track we relayed in the whole of 2012.” 

That impressive achievement has come about through redesigning many of the products that go into the railway track renewals to make them quicker to install, rethinking the work processes and training the workforce to operate like slick Formula One teams.

What has driven the change is the need to reduce the amount of Tube weekend closures to keep an increasingly busy London moving even outside the working week and to get ready for the introduction of ‘Night Tube’ services expected from 2015.

The future - LU needs industry help

The Tube track renewals teams are facing some big tasks next year involving the replacement of junctions in the deep Tube at Walthamstow, Tottenham Court Road, Camden Town and Liverpool Street. “This will require unique solutions for major challenges such as the break out of concrete, lifting in confined spaces, extraction of heavy material through confined underground locations and environmental management – particularly the dust and heat that results from working with concrete,” McInulty explains. “We need the industry to help us come up with the best ideas as we can as to how to do the work most efficiently and safely. Anyone wanting to get involved should visit the TfL Technology Innovation Portal.”

“We started work on how we can achieve that well ahead of demand. Our aim is to have far fewer weekend closures,” McInulty says. “But we still have some thinking to do and we need the whole industry to help us with that (see box).”

Track renewal on a 150-year-old Tube network is not something that can be avoided but it can be made far more efficient, McInulty says. And he has some good results to share. “We have between two and three hours work time a night to replace sleepers, ballast and rails which we do in a staged approach replacing ballast and sleepers on one shift and then delivering the rails the next. When we started the improvement process in October last year we were doing 2-3m a night. Now we can manage up to 20m.”

The obvious question is how?


“On access, we have worked across the organisation to reduce every single minute of non usable time and turn it into usable time in terms of safe site set up and starting work – it’s a matter of mindset. We are now 22% quicker at getting boots on the ground. Everyone from the signallers to control room to the operations team all understand what we are trying to achieve. We have not cancelled any trains to gain the extra time but we have re-routed engineering trains to get better access.


“We have set up a training facility where we have drilled each individual in the processes and got them quicker and quicker, like Formula One tyre changes. We are up to 20m from 2m now and we picked up some new ideas on a recent visit to Tokyo, particularly on ballast, that will move us beyond 20m.


“We have looked at every tool we are using and tried to refine each of them to get them lighter or create a quicker method. For instance we have moved from using Kango jacks for compacting the ballast to lighter vibrating vertical tampers that get the ballast in position much faster. We have introduced smaller, more agile, mini diggers to the traditional civils plant. And in future, working with Balfour Beatty, we are going to procure special 5t mini diggers specifically designed for LU overnight track renewals.


The sleeper fastening system, the pot the conductor rail sits on and rail welding have all been rethought, as has track drainage.

Sleeper fastening: “We have redesigned the sleeper fastening system for speed. There used to be three parts that required labour to install and configure on site. That’s been replaced with a fast clip system developed with Pandrol that’s safer and quicker to place,” McInulty says.

Conductor rail: “The conductor rail arrangements used to have 15 components that were not easy to adjust; now we are down to four that can be pre-assembled and adjusted simply on site. That was something we adopted from Balfour Beatty’s work on the mainline railway.”

Welding: “We have switched from traditional Alumic thermic welding which took 40 minutes, to flash butt welding which takes seven minutes. That’s something picked up by attending industry networking events like Future Rail,” McInulty explains.

Drainage: “Our work on track drainage had previously been constrained by the availability of engineering trains to bring the drainage product to site. It was often a separate activity to track renewal. So we replaced the need for trains. We looked at what was going on in Europe and collaborated with Mercedes Benz to introduce a rail-wheeled tractor ‘Unimog’, converted to suit LU rail so now we can deliver drainage without reducing the amount of new track we are installing.”


“We are working on ways to deliver ever quicker track renewals and are confident that we will be leading with innovations that we can share with the world,” McInulty says. “For instance, we are bringing in mechanized rail movement, using track rail transporters that are like little robots that move rail into place – much safer, and twice as fast as using traditional labour. And we have introduced robotic saws to mill the rails which again is faster, and safer.”

Looking ahead LU has plans to create a new track formation that doesn’t need to be replaced every 40 years, more like 80. “We are looking at basic engineering principles to develop a better product to leave a better legacy for the people managing and maintaining the Tube in the years to come.”



If you would like to contact Jackie Whitelaw about this, or any other story, please email jackie.whitelaw@infrastructure-intelligence.com.