The Narrabeen Substation Control building houses the live electrical switchgear and equipment that control the adjacent substation. As part of the upgrade of ageing assets, Multiworks was engaged directly by Ausgrid as Principal Contractor to replace the existing roof while maintaining the live operations of the substation and the electrical network. The works included: replacement of roof tiles with Colorbond sheets, installation of CFC sheets, replacement of gutters, installation of new downpipes, installation of earthing spires and installation of new anchor points.
Prior to commencement of the roof replacement works the Narrabeen Control Building was impacted by a storm causing leakage inside the Switch-rooms. Ausgrid engaged Multiworks to execute emergency works to stop the leakage. This required the roof replacement works to be brought forward and delivered within a significantly constrained time frame.
Multiworks effectively mobilised a skilled team including additional resources from interstate. Due to the poor condition of the existing roof, Multiworks made the entire control room building watertight through implementing anchor points and tarping. This provided a temporary shield around the whole building, eliminated any impacts due to poor weather and ensured the ongoing operation of the control room.
Multiworks delivered the project one month ahead of schedule, while also completing the Castle Cove Substation works.
Multiworks was responsible for the replacement of roof metal sheets with Colorbond sheets, replacement of gutters, installation of new downpipes, construction of stormwater inlets and installation of new anchor points. Multiworks delivered all scope while ensuring the ongoing operations of the live electrical substation.
A key challenge in the roof replacement works involved implementing appropriate physical protection over the existing Frequency Injection Units (FIUs). Due to the sensitivity of the assets and client requirement that only one FIU could be de-energised at a time, Multiworks developed and implemented a staged works program over the FIUs. Multiworks effectively planned and scheduled materials and resources to ensure protection over the unit while replacing the section of roof directly above. The protection was then stripped so that the FIUs could be re-energised.
Additionally, Multiworks developed an innovative ‘Rolling Scaffold’ within the substation that offered fall protection and acted as a physical barrier to ensure the substation equipment was not exposed to falling objects.
The Chullora Substation Control building houses the live electrical switchgear and equipment that controls the adjacent substation. As part of the upgrade of ageing assets, Multiworks was engaged as Principal Contractor directly by Ausgrid to replace the existing roof without any interruptions to the electricity network.
Works took place on the existing live control building, housing equipment for this 66kV Substation. Key scope involved ACM eave replacement, removal of roof tiles, installation of two layers of Compressed Fibre Cement sheets, installation of Colorbond sheets, reinstating existing gutters, installation of new downpipes and installation of new anchor points.
During the preliminary planning, it was noted that the height from the pitch of the roof to the soffit was greater than 0.8m. Due to the substantial height difference the existing anchor points could not be used as a means of fall arrest. As a result, Multiworks proposed and successfully implemented a construction methodology that provided a means of fall arrest utilising anchor wraps. The project achieved zero safety incidents.
The Victorian Government has mandated the rollout of Rapid Earth Fault Current Limiter (REFCL) installations across nominated Zone Substations in AusNet Services’ network, including at the Lilydale Zone Substation. Installation works included:
- Two new REFCL(s) units in bunds and footings
- Two new 22kV switched neutral bus kiosks onto new footings
- A new REFCL Room on to new pad footings to house associated inverters and control equipment
- A new modular Control Room onto new striped footings
- A new cable trench (600mm Wide x 600mm Deep) running north west to south east for associated control cables Conduits for control cables
- Associated reinstatement and surfacing
Replacement works involved:
- The existing NER with one new NER onto new pad footing
- Existing station service transformers (SSTx) with two new 750 kVA kiosk type units onto new pad footings and AC changeover boards
- Both existing Capacitor Banks with Metal enclosed Cap Banks with pad footings for REFCL compliance.
The Heywood Terminal Station (HYTS) 500 kV CB Replacement project includes establishment of two new 500 kV switch-bays to convert the incoming MOPS and TRTS line bays to a double-switched arrangement.
Multiworks was engaged by Zinfra to carry out all civil work associated with the project scope, including:
- Replacement of existing MOPS/TRTS line bay ROIs, CVTs and Surge Arresters
- Replacement of M1 and M2 transformer 500 kV Surge Arresters
- Decommissioning of 22 kV No.3 station services transformer
- Replacement of the 415 V station services infrastructure
- Installation of new 500kV Bus protection, new X & Y CBM scheme
Among other elements, Multiworks was engaged by Zinfra to construct a new 50,000L containment tank within the existing electrical substation.
Due to its size and weight, the containment tank was required to be constructed in-situ. Multiworks utilised prefabricated formwork boxes to set-out the tank and pour its 3 compartments in a singular pour.
Multiworks’ works onsite involved all civil works related to the contract for the new MTM Cheltenham Substation. Included within these works were building bored piers (600Ø 3.6m deep), Overhead 1500 Switch Feeder bored piers (900Ø 10m deep), Overhead 22Kv (900Ø 10m deep), Undertrack bore x3, conduit trench installation, Building concrete slab, Transformer bay Concrete slab and Brickwork, Security fencing and gates.
All works were completed ahead of program whilst working under the site conditions and restrictions imposed from the interaction with the public and under live rail conditions. PTV commended Multiworks on the management of the Cheltenham station car park (public & vehicle interaction) whilst the retaining wall and the changes to the carpark were completed.
Due to patronage growth on the Melbourne tram network, the Victorian Government ordered 50 new trams, known as E‐Class trams, to supplement the existing fleet. These trams have a higher passenger capacity, additional on‐board features and increased electrical requirements that will contribute to the modernisation of the network. As a result, substantial upgrade to the power supply infrastructure was required including the subject works at Brunswick Substation.
Works involved demolition, exposure of redundant cables, installation of conduits and foundations, new drainage systems, landscaping and the treatment/ removal of all waste as Contaminated Cat C. The work was undertaken in a methodical sequence as the sites was incredibly confined.
Engaged by CPP directly, Multiworks was responsible for the construction of the in-situ brick control building at Deer Park Terminal station – constructed to house the site’s new electrical high voltage equipment. Multiworks was responsible for the installation of all related services including security, HVAC, lighting and fire detection. Despite a two-month delay associated with the building permit, Multiworks achieved handover of the completed building in time for testing and commissioning by the original project deadline. Multiworks was awarded additional scope including fencing and earthing works.
Following the award of the Mentone Zone Substation Multiworks secured the delivery of refurbishment works at the Noble Park Zone Substation. The similarities between the two projects enabled Multiworks to capitalise on available economies of scale and to resource both jobs efficiently. The project works included:
- Construction of a 22kV Control Room
- Significant infrastructure works
- Considerable installation of conduit runs
- Resurfacing & reinstatement of roadway.
