Dublin LUAS – OLE Parafil Replacement

The project was for the Design, Supply, Build & Commission into service of replacement overhead line support equipment, required due to reliability issues of the existing equipment, specifically the
existing Parafil rope.

This turn-key project was conceived and delivered over an extended period of time, with initial concept discussions, assistance to TII in the development of business case, risk assessments, and ultimately the core works in the autumn of 2020.

Concept & Risk Assessments
The Dublin LUAS system was suffering Parafil failures on the red and green lines. There was significant evidence of historic failures, and Pod-Trak were contracted to undertake an analysis of failures, and risk assessments based upon failure data, equipment type, and the environment where the equipment was operating. The risk assessment concluded that there was an unacceptably high risk of failures
resulting in significant risk of public electrocution and disruption to the LUAS service. This risk assessment was used as a key piece of information to develop the business case to renew the Parafil rope assemblies.

Design
Pod-Trak have extensive knowledge of Tramway overhead line systems, and used this knowledge to develop a design that was both reliable and aesthetically pleasing. Surveys were undertaken to assure a
high quality design, with the results of the surveys used to inform the design process. With the good quality design information, we were able to identify a significant non conformance within the existing arrangement for which we were able to design out as part of the Parafil replacement project.

A key feature of Tramway equipment is for it to be visually nonobtrusive. To achieve this Pod-Trak commissioned a new insulator design which was developed, tested and installed within the timeframe of the project.

Supply
All equipment supplied for the project was specified to minimise visual impact, whist providing a robust mechanical and electrical support for the contact system. Materials were specified and secured through our supply chain which included the development and production of the new 1.5KV insulator. The insulator development was undertaken in accelerated timescales to provide Dublin with best possible solution using available proven technology and is a key achievement in the delivery of the project.

Construction and Entry into Service

Construction was completed over short nightly possession and isolation, using 4 MEWP teams and all completed under the constraints of Covid-19 where our teams were confined to their accommodation and were not permitted to interact with the LUAS maintenance / isolation teams. Risk assessments were completed and working practices agreed between all parties that allowed the works to proceed in an efficient manner. The geographical scope of the project was between Fatima Stop and the Ashling Hotel and included pedestrian management and traffic management. All works were completed in a safe, assured manner and handed back into service on a day by day basis.

Client walkouts were completed weekly, with great feedback as to the quantity and quality of work undertaken. Following construction a full set of as-built drawings were produced for inclusion into the client H&S file.

OLE Maintenance – Luas

Transdev Ireland has been operating the LUAS since 2004 and in 2019 they took over the maintenance, including Overhead Line Equipment (OLE) maintenance from Alstom. Due to the changeover period some maintenance activities had fallen behind and Pod-Trak was asked to provide some teams to help with the backlog.

Our teams have carried out numerous projects on the LUAS system over the years and are familiar with the equipment and standards required for maintenance, especially OLE maintenance. When the initial request came through from Transdev for support we were able to mobilise at short notice providing experienced staff, plant and transport on nightly basis to carry our maintenance tasks and inspections. We have always strived to be readily available for our customers where possible – especially in situations where project works have fallen behind.

To support the works a Mewp with pantograph was provided for panning the contact wire. Due to a lot of areas being street running with nowhere to leave the Mewp between shifts it was transported nightly between the Red Cow Depot and site.

The LUAS consists of two main lines, the Green Line and Red Line which were linked in 2017. The system is similar to Manchester Metrolink and other light systems across Europe.

Crumpsall Metrolink Stop

To facilitate the construction of the new Trafford Park Metrolink Line, a new turnback had to be constructed at Crumpsall on the Bury Line. Modifications to the existing OLE were required along with new installations. Works were staged to ensure minimal disruption to operational tram service and to meet the Trafford Park Line project completion date.

The staged works were planned over three main disruptive worksite blockades and midweek night preparation shifts. The works included twin cross over cantilever installations on the Trafford Park turnback track and the new inbound and outbound cross-over tracks The first blockade saw the installation of OLE poles and head spans throughout the platforms to facilitate the removal of an existing bridge.

The second blockade comprised of installing new contact catenary droppers and modifying the existing and new OLE to ensure height clearances over the new pedestrian crossing and turnback crossover.

In the lead up to the main and final blockade a number of midweek engineering hours shifts were available to carry out preparation works to de-risk the main works. During the final blockade weekend, SPS works were completed along with the installation of contact wire runs on the inbound and outbound crossover including the turnback track.

Following the installation, the works were successfully tested, commissioned and handed back to operational service. All assurance paperwork and hand back documentation was completed and submitted following the final blockade weekend.

Langley & Taplow AFA

Rail for London (RfL) Crossrail Operations were undertaking a station improvement programme to ensure the Crossrail network will become a fully accessible railway by the time it opens.

Four stations – Hanwell, Iver, Langley and Taplow on the Great Western Railway were upgraded as part of this programme with Pod-Trak delivering Langley & Taplow.

Installation of the footbridge required adjustments to the aerial earth wire heights, alterations to the system heights and registrations at either side of the new footbridge.

Working on the existing Furrer & Frey equipment, new earth wire was installed through the station at a reduced height to clear the bridge soffit and was fixed onto new anchors and bonded to the next section of earth wire for continuity.

The OLE was registered with Furrer & Frey SIC cantilevers on stove pipes which were then swapped for longer stove pipes to achieve the new lower catenary height and the SIC cantilevers were swapped for reduced system height SIC cantilevers.

At either side of the new bridge the spans had new droppers installed to grade the OLE. Final registration to new design and pantograph checks were carried out on each of the 4 lines at Langley and Taplow.

Due to a 3rd party possession, access to the UP / DN Main at Langley was not available for rail mounted plant. To meet the requirements of the programme, two 3t Mewps were lifted onto the platform using a 300t crane at a 62m radius. Works were then delivered using the Mewps and a tower scaffold.

Wigan Depot Enabling

As part of the Wigan Springs Branch Depot remodelling project, Pod-Trak carried out enabling works at the depot entry to allow the depot to be constructed without affecting the mainlines. This was required due to the complexity of the points and crossovers along with the OLE termination structures.

The equipment consisted of auto tensioned Mk3b catenary headspans and cantilevers with switch gear. The scope included:

  • OLE height and stagger surveys prior to any works commencing and post height and stagger surveys on completion of the works
  • Installation of a PES on 2 Headspans to allow access / site setup prior to the isolation being granted
  • OLE slewed and registered to the new alignment following the installation of new points
  • Replace four life expired 4-track Headspans, this included moving the mast insulation to mid span and the removal of two auto tensioned Contact and Catenary wire runs closest to the new depot
  • Redundant balance weights, wire, SPS and two cantilevers all recovered from site
  • Install 8 sets of compensation weights on the 4 headspans to compensate for the 2 wire runs that were removed
  • Profile and register headspans
  • Remove from site two switches that were previously decommissioned

Due to the complexity of the works and proximity to the main lines they were staged over a number of weekend possessions. All materials management and build-up was completed midweek between the possessions.

Following the successful completion of the works, the client was able to commence their electrification of the depot.

Maintenance Depot – Bounds Green

With the introduction of IEP trains to the East Coast Main Line, an existing rolling stock maintenance depot required a variety of modifications to allow effective maintenance of the new IEP trains.

At Bounds Green maintenance depot, this involved the installation of a crane to enable the maintenance of roof-mounted modules. To facilitate full utilisation of the crane within the depot building, the Overhead Line Equipment (OLE) system had to be modified to allow safe passage along the length of the Depot.

As a result the OLE system needed to be retractable. To achieve this the OLE system along Road 11 was re-designed as a Furrer and Frey retractable overhead conductor beam system (ROCS).

The works were delivered in two key stages and had to be completed within the constraints of a four-road live operational maintenance shed for the duration. Along with the OLE scope Pod-Trak provided OTP to assist with the removal of concrete walkways, as well as the installation of an elevated walkway and access requirements for all M&E installations.

TGW Electrification

As part of the overall Great Western Electrification project from London to Cardiff, this scheme covered the area between Bristol Parkway and Cardiff at a distance of 77km.

Continuing the strong relationship with Balfour Beatty on electrification projects, Pod-Trak were engaged as a key supplier to provide skilled teams to work on SPS installation, wiring and final registration. This was backed up by the provision of Construction Management, Engineering Support, POS Planning, Lift Planning, POS and Plant.

The Pod-Trak teams moved through sections of the project to carry out final registration and ensure the new OLE was ready for entry into service. All assurance paperwork was completed and submitted to the client for each location.

Works were delivered over a series of weekend and midweek possessions with a number of key blockades where a huge amount of work was delivered. Including the along track works, Pod-Trak were also responsible for the tie-in to the Hitachi Depot at Stoke Gifford.

Having worked in the depot on numerous occasions and ongoing OLE maintenance the team were familiar with the depot procedures and this proved to be an advantage for the client. On the 6th January 2020 the first test train ran on electric power from Cardiff Central Station bringing to an end a long project to electrify the entire route from London Paddington.

Gospel Oak to Barking Electrification

Pod-Trak undertook the electrification of the Eastern half of the Gospel Oak to Barking route on behalf of Balfour Beatty. The electrification of the lines was undertaken by Network Rail as part of their London Railway Upgrade Plan which doubles the capacity on the line and improves the air quality of those who live and work near the railway.

The GOB electrification uses Series 2 and Furrer+Frey OLE equipment, however the route interfaced with UK1 and OLEMI equipment ranges. Working with a broad range of equipment requires experienced and adaptable staff, which Pod-Trak were able to provide.

The scope consisted of new OLE installation, including main steel, small part steel, wiring, switching, bonding and final registration. All works were fully assured by our construction and engineering teams backed up by signed quality check sheets and ITPs. All construction activities were completed through blockades and weekend possessions, which required careful and considered planning to ensure safe and efficient delivery. On completion of the construction and assurance activities, the route was panned with Pod-Trak’s plant as final confirmation that the OLE was fit for the passage of electric trains.

Prior to our mobilisation, the project had been running for two years and had been criticised by the media as another delayed electrification programme. Following the Balfour Beatty and Pod-Trak mobilisation in summer 2017 and an intense period of site activity the project was successfully energised during the Christmas 2017 blockade. This was shortly followed by the pantograph ready milestone achieved in early in January 2018.

Ely Bridge

A new road was built to bypass Ely town centre by connecting the A142 at Angel Drove to the A10 Stuntney Causeway. The route of the new bridge crosses over a river and flood plain, the Bethnal Green to Kings Lynn Railway and the Soham Branch railway lines.

The Bethnal Green to Kings Lynn lines are electrified with 25kV AC OLE. Due to the proposed soffit height of the new bridge, modification of the OLE was required by Pod-Trak in order to maintain suitable electrical clearances.

The existing OLE was Mark 3B Simple Auto Tensioned equipment. Headspan structures are predominantly used for support and registration. Un-insulated overlaps were located directly beneath the proposed bridge location on the Up Main and Down Main lines. Existing contact wire heights were greater than nominal height of 4.7m due to a level crossing previously located in the vicinity.

The Lloyds & Martin private level crossing was previously located at 69m 54ch on the BGK lines. This level crossing had recently been removed but OLE wire heights remained higher than normal. Pod-Trak designed and installed the new OLE formation and re-profiling.

The scope included:

  • Install new Down Goods Loop RC
  • Install contenary wires on all three lines
  • Temporarily support wire runs from middle span wire and remove redundant equipment
  • Install new lower span wires
  • Install new LDVs
  • Adjust Up Main RC heights to achieve electrical clearances
  • Install new droppers
  • Re-register wire runs
  • Adjust headspan geometry
  • Height and stagger survey and adjust equipment as required to new design values
  • Carry out new bridge deck bonding

Access to the site was agreed with a local landowner and all areas used were left in as good if not better condition than before.

Temple Mills Eurostar Depot

In May 2016 Pod-Trak was awarded the contract to supply all labour, plant, materials, supervision and management to undertake the OLE removal works (enabling works) to remove head spans in 7no locations.

The scope included the careful removal of the existing equipment and retention of the OLE wires for reuse in the new works. The scope also included the installation of new OLE equipment (Furrer & Frey), line wires and retractable motors. The works included testing and commissioning of the new infrastructure. The delivery of the project was split in to 3 key stages to facilitate the depot remaining operational throughout, and to allow the steel work subcontractor to install the new steel support structures within the maintenance shed.

The project was successfully completed and handed back in 2017, on time and without incident.