IME Consultants (IMEC) is pleased to
announce the successful completion of a high voltage cable installation project
near Mt Isa, Queensland. A total of four 240mm2 cables were
successfully installed within a 960m deep production shaft terminating at substations
located off various levels in the shaft to contribute to a site wide HV upgrade
project.
The cables were installed within the active
production shaft, serving as a huge challenge to not only coordinate the
scheduling of the installation works with the mining production requirements,
but also to safely gain access and space within the shaft.
IMEC have established a solid relationship
with Murray Engineering Pty Ltd (Principle Contractor) through the provision of
engineering support across a number of their other successfully completed cable
installation projects which most notably includes the Gwalia Deeps HV
Installation in Leonora W.A. completed in 2013, which is considered to be the
deepest single point suspended cable install in Australia at 1370m
.
Murray Engineering Pty Ltd (MEPL) appointed
IME Consultants to provide support to the project with developing a
methodology, installation equipment and materials design and specification,
procurement support and finally onsite construction technical support.
The project was broken down into 3 key
phases; ‘phase 1’ was to install permanent wall brackets to the shaft wall
which cable clamps would be later affixed to. ‘Phase 2’ would constitute the
lowering of the cables down the shaft and then finally ‘phase 3’ was to install
the lowered cables on to permanent wall brackets installed to the shaft wall.
The cables were large 240mm2 copper
XLPE insulated cables required to transmit 11kV of electrical power down the
shaft and into the various sub-level substations. There were four separate
cable installations with each cable being lowered from the surface collar area.
IMEC designed a specialised skid based
sheave arrangement that would fit into a recess between the headframe structural
bracing and allow the lowering catenary support wire rope to be deflected
accurately into the compartment within the shaft where the cables would be
installed. The skid based arrangement also provided for a safe work deck for
workers to clamp and fix the HV cable onto the supporting catenary wire rope.
This skid would be fitted with handrails designed to Australian standard
ensuring the workers would be safely protected whilst working next to the open
hole.
The skid arrangement enabled full Non-Destructive
Testing of all equipment to be carried out prior to mobilising to site, negated
the need for a crane for installation (which would be typically used) and provided
a safe work area for MEPL employees throughout the lowering at the shaft collar.
An MEPL developed custom cable clamp was
used to fix the cables to the catenary wire rope for lowering the cable into
the shaft. The cables were then transferred from the catenary wire rope to wall
brackets which were designed by IMEC for the permanent cable support. All of
which was designed in accordance with the applicable Australian Standards and
the site specifications.
Strict QA/QC was carried out during the
installation of all equipment including anchor pull testing, MPI of fabricated
item welds, conformance testing/inspection of equipment and material
certificates for procured items. The strict conformance of all items was both
prudent for the safety of persons and client equipment along with Mining
Regulations.
The successful completion of this project
marks a significant achievement for both IMEC & MEPL in demonstrating their
industry leading capabilities for not only delivering projects of this nature,
but also the technical & management skill sets of their experienced staff.
