New standards set in track renewals

The joint Network Rail/Jarvis Rail team meticulously planned the 54-hour possession (October 15-17) between Nuneaton North Junction and Colwich Junction, resulting in a combined total of 3,652 yards of track renewed. This comprised 1,234 yards of ballasting, 1,234 yards of sleepers and 1,184 yards of rail – more than double the industry standard. The complete renewal was handed back on time and at full line speed.

Standard industry yardage usually amounts to a combined total of around 1,800 yards, comprising 600 yards each of ballast, sleepers and rails. Additionally, by handing back at line speed, the team was able to avoid the usual temporary speed restrictions (TSR) and ensure passengers immediately received the maximum benefit out of the new piece of track.

‘This is an outstanding achievement for the Jarvis Rail team, and the UK rail industry and was only possible through the strong teamwork between Jarvis Rail and Network Rail,’ said Pat McHale, Jarvis Rail Managing Director.

‘It is the first opportunity we have had to showcase key components of our innovative Accutrack system in one possession. The technology includes the Rapid Ballast Excavator (RBE or ‘mole’) and Track Renewals System (TRS or ‘slinger’), which together help produce a mechanised, production line approach for safe and efficient track renewals.’

Network Rail’s West Coast Programme Director Tom McCarthy said: “This was a great example of joint working that delivered tangible benefits to passenger immediately. This new innovation will help transform rail renewals in the future delivering significant savings and safety benefits.”

The scope of work for the project specified a complete renewal of 1,184 yards on the down slow line and included the provision of new ballast to a construction depth of 300mm below sleeper bottom. The track construction elements comprised G44 fast clip concrete sleepers and CEN60E1 rail.

Mr McHale said: ‘Traditionally, the relaying of sleepers, rail and clipping up are undertaken at a relatively late stage in the renewal, but by using this methodology, the track was built before the re-ballasting activity was completed.’

Application of Accutrack
As part of the delivery process, the existing track was burned into 60 foot panels and uplifted traditionally, using two heavy duty track relaying machines. The panels were loaded to Salmon wagons for transportation from the site. The conventional methodology was then relegated to back seat status, as the RBE (mole) and TRS (slinger) were given centre-stage. The RBE completed spoil removal to formation level under laser controlled conditions. One and half miles south of the site, the TRS began the process of prefabricating 5x235 yard panels in a simultaneous operation to the re-ballasting exercise.

Panels were built on top of the existing rails of the down slow line over 1,200 yards of the build-up area. When complete they were transported two at a time by a TRS to the immediate south end of the worksite. Bottom ballast was placed using side-tipper wagons. This was graded to design and consolidated by a laser dozer.

The production line process enabled the final panel to be transported by the TRS and laid immediately onto the newly prepared ballast bed. Welders were able to start work early to eradicate the temporary joints created by the transition rails, panel ends and insulated block joints (IBJs). Following completion of the relaying, auto-blasters were used to tip stone, and then the tamper, regulator and dynamic track stabiliser were deployed to create design track geometry and attain line speed tolerance standards.

About Accutrack
Accutrack® is a complete track renewal process combining unique technology with rigorous processes and highly skilled people. Within a single possession period, it delivers fully completed track ready for line speed operation. Key Accutrack technologies are the Rapid Ballast Excavator (RBE) which uses laser alignment and 3.8 metre wide jaws to remove 450mm of spoil in a single pass, at a rate up to 1000 tonnes per hour. The Track Renewals System (TRS) has the capability to deliver and place steel or concrete sleepers, lift and remove/replace track panels and install long lengths of rail. Using the TRS technology, production rates are generally twice that of traditional methods.

Ends

For more information, contact
Diane Mangan, Jarvis plc, mobile 07843001158, diane.mangan@jarvis-uk.com,
Toni Jackson, Jarvis plc, mobile 07919921092, toni.jackson@jarvis-uk.com
Or Steve Turner, Network Rail, on 020 7904 7322


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