The Beryl and Mount Piper Substations contain 132/66kV networks to supply the local townships. Due to the aging condition of the existing transformer bunds a new containment system was required to allow for the containment of water and oils should there ever be a fault with the transformer. Multiworks provided all upgrade works at the two substations to upgrade this existing oil containment system. This involved the construction of new primary spill oil tanks, upgrade of existing bunds, installation of new connecting pipework for both substations and flame traps for Mount Piper only.
Adding to the complexity of this scope was the proximity of the proposed containment systems to the adjacent high-voltage and in-service electrical equipment. Multiworks took over the design of this element to create a piling retention system adjacent to the structures and to ensure the site remained operational through the work.
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 were engaged by Citipower/ Powercor to excavate and construct a new in-ground electrical cabling pit at Richmond Terrace. Work included;
- Excavate around pit and expose existing 66kV feeder cables – 3 x cable joints
- Demolish existing pit and install new precast cable pit
- Backfill excavation and reinstate road
Multiworks was responsible for the design, procurement and installation of 700m of security fencing at the Mount Beauty Terminal Station. This involved the mobilisation of internal crews to undertake the installation of fencing and to establish the pit and pipework for future electrics. The fence upgrade works were complex due to the number of underground services beneath the substations’ boundary line. Multiworks obtained all permits in a timely manner and executed the works without interruption to the electrical network. The project achieved zero safety incidents.
This project for the Department of Defence involved the installation of new fencing works at RAAF Base Laverton, RAAF Williams Point Cook Base, HMAS Cerberus and Ringwood East Depot. Involving over 2.4km of fencing, most of which high security, was heavily involved with local stakeholders and required thorough planning.
Part of these works also involved the installation of fencing within tidal zones and working on shorelines up-to 4 meters deep. The fence was constructed utilising screw piles and a Multisteel designed baseplate.
The Tottenham Substation contained a legacy triple interceptor pit and transformer bund drainage system onsite that was abandoned and not in operation. This project involved the re-use part of this existing abandoned system where possible in constructing the new system. The existing triple interceptor pit was removed and a Humeceptor pit (HCP) and associated pipework was installed in its place.
Other work onsite included new pits and DICL pipework through the existing substation and the re-lining of transformer bases with fibre cement.
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.
Multworks worked with V/Line as principal contractor to carry out ARMCO pipe upgrade works as part of their essential maintenance program across the network. The work involved the relining of the bottom half of ARMCO culverts with concrete to assist in maintenance and reduce corrosion.
The works were carried out in close consultation with V/Line and local council to ensure nil safety or environmental incidents occurred.
