Saraji Mine Optimised Stripping Workshop

To facilitate the acquisition of up to 50 additional Heavy Mining Equipment (HME), the BMA Saraji Mine (SRM) engaged Walz to build an extension to the existing workshop to include 4 additional Ultra-Class (UC) bays.

As Principal Contractor, Walz scope included:

All works associated with the relocation of existing buried services.
Demolition of existing tool store on the western side of the existing HV Workshop.
All bulk earthworks to building up the pad and hardstand for the new workshop extension (10,200m3)
Bulk excavation for the pad footings.
All concrete works for pad footings and pedestals.
Formwork and concrete for new workshop slab (720m3)
Supply, fabrication, surface treatment, erection and cladding of new workshop (65m long x 20m wide x 21m high).
Supply and installation of electrical and mechanical works, including satellite tank farm and point of lube (POL).
Testing and commissioning.

580 Area Tank Inspection & Repair Program

Walz were engaged by our client to complete necessary maintenance repairs and improvements to four 22m diameter thickener tanks, as part of their periodic API inspection requirements. The scope of work involved the replacement of corroded pipework, internal feedwells, structural repairs to the strakes, and full internal blast and paint. The work was scheduled over a 12-month period to coincide with the regular operational downtime, with Walz working with our Client to ensure that each thickener tank was returned earlier than scheduled, to minimise the overall duration of the program of work and thereby the time spent at reduced operating capacity.

 To complete the repairs of each thickener tank, Walz designed and built a full internal scaffold system that provided access for the blast and paint work and replacement work consisting of 54T of At-Pac Ringlok scaffold. This scaffold was erected to provide access to all internal surfaces of the tank, as well as a large working area for the replacement of the internal feedwells and pipework.

 Key highlights were:

Completion of 2500m2 of blast and paint
Removal and replacement of 300m of associated piping
Completion of nearly 14,000hrs injury and lost time free

Removal and Installation of R10M Conveyor GRM

BHP Mitsubishi Alliance (BMA) Goonyella Riverside Mine (GRM) replaced the rejects conveyor gantries and trestles as part of the Goonyella R10M Conveyor & Trestle Replacement project. This work was part of a planned upgrade to the existing R10M Conveyor required to rectify a series of identified deficiencies during a major 6 week outage.

Walz fabricated the new conveyor gantries and trestles under a separate job number, so our scope for the R10M Conveyor Replacement works involved removing the existing conveyor gantries, GTU and trestles scope and installing the newly fabricated conveyor gantries, GTU and trestles. The work included structural, mechanical, piping and electrical disconnections, removal, installation and reconnections. Walz provided cranes, operators, boilermakers, fitters, riggers, scaffolders and electricians as well as development of complex lift studies, a detailed methodology and commissioning assistance. We provided the following:

150t Hydraulic Crane
80t Hydraulic Crane
28t TIDD
Supervisors, Crane Operators, Riggers, Boilermakers, Fitters, Scaffolders and Electricians (24/7)

With the support of Walz equipment and a professional crew of Walz personnel and key subcontractors, the project was safely and successfully completed LTI free.

BMA Goonyella – Dewatering Screens Project

Coming off the back of successfully completing the installation of the new Horizontal Belt Filter BF703, we were again engaged by BMA to assist with an upgrade of an existing dewatering screen to larger dual screens. The installation of these dual screens would assist operations with rectifying a bottleneck identified in Coal Preparation Plant 1 (CPP1), resulting in increased production rates.

These works require us to work alongside the existing CPP1 to install the new platform that will house the new dewatering screens and associated componentry. Our scope includes the supply and installation of the entire work package, including all structural steelwork, platework (chutes, underpans, feed boxes), a new gantry section and supporting trestle, pipework, handrail, grating, valves and the new conveyor componentry. We will be working alongside a number of our key subcontractors for these works who will be assisting with the civil works, electrical works, modifications to the existing conveyor belt, re-installation of an existing belt weigher and on-site installation of wear lined pipework.

Our team have become accustomed to carrying out complex on-site installations, with this project presenting its own challenges. To successfully complete this upgrade, we will be required to carry out a significant portion of the works during three plant shutdowns.

BMA Goonyella – Horizontal Belt Filter

Continuing our ongoing relationship, we were engaged by BMA to carry out the installation of Horizontal Belt Filter BF703 at its Goonyella mine in Central Queensland. It was our first time working back at the Goonyella mine in recent years and it was a great opportunity for our team to demonstrate our capabilities working alongside a new client team.

Our works for this project included the full turnkey package. We worked alongside BMA to assist with the procurement of key items such as pumps, drives, handrail, grating, valves, pipework and other miscellaneous componentry. We also looked after the fabrication of plate and structural steelwork packages, which were integral to the installation of the new Horizontal Belt Filter being supplied by BMA. This project once again gave us the opportunity to work alongside our trusted subcontractors for the civil, electrical and instrumentation works. Once commissioned, the upgrade would see an increase in the recovery of dry product through the mine.

The project was completed safely and on time, demonstrating our capabilities in this field and establishing our presence as a key contractor for further works at Goonyella moving forward.

BMA Hay Point – Trestle Deconstruction

Based on our successful track record on multiple projects at Hay Point terminal, we were engaged by BMA to deconstruct and remove the original trestle and the 17BP conveyor installed when the facility opened in 1971. The ageing 1.8km structure transported coal from the terminal to waiting bulk carriers for more than 40 years and was decommissioned late in 2016.

Working from jack-up barges, our crews are dismantling the trestle and conveyor in sections, and transferring approximately 6,500 tonnes of steel to Half Tide Harbour by barge. Our work at Hay Point is ensuring that aging infrastructure is safely and carefully removed in order to best protect the local environment. In March 2019, Walz Group achieved two years recordable injury free on the project.

In conjunction with the main work of dismantling the trestle, Walz Group is undertaking additional separable portions of work under the same contract. Each separable portion of work is outlined below.

Disposal of Waste Material

Once on-shore, the trestle sections are separated into steel, concrete and timber components and prepared for transport to recycling facilities.

Dewatering and Processing of Pile Water

If the water located in the piles is not inert or has the potential to cause visual pollution, Walz is responsible for processing and filtering the water prior to release off-site.

TT8 Top Deck Removal

We are removing and disposing of the existing TT8 top deck, and installing the new structure and supporting componentry.

Berth 1 to MD2 Footbridge Installation

We have been contracted to install a new footbridge (Footbridge 2), with associated structural support and access walkways. The new structure will connect Berth 1 to MD2 after the deconstruction of 17BP conveyor and roadway.

Berth 2 Shutdown Works

The current shiploader infrastructure requires upgrading and refurbishment, as well as installation of new elements. We have completed:

Fender maintenance and chain replacements
Installation of a new davit crane
Upgrading the ship access gangway and supporting structures
Removal of redundant fenders
Other miscellaneous works as required

Berth 1 Shutdown Works

This refurbishment work is similar in nature to that outline for Berth 2 above and incorporates:

Fabrication and installation of a new tripper
Installation of new transfer chute and upgraded pulleys
Repair and surface protection to conveyor structure and rail girders
Supply and installation of new tripper rail
Installation of new walkways between berthing dolphins
Installation of new top Davit Crane
Fender chain replacements

Sedgman – Sonoma High Cut / Low Cut

Located 6km south of Collinsville in Queensland’s Bowen Basin, QCoal Group’s Sonoma Mine produces up to 4Mtpa of hard coking and thermal coal products.

Our client, Sedgman, has operated the Sonoma plant since it was constructed in 2007, and were seeking support for the detailed design, engineering, procurement, and construction of the High Cut Low Cut Brownfield Upgrade of the coal handling and preparation plant. We worked with Sedgman to provide SMP civil works and a range of fabrication and protective coating services. Steel fabrication included steelwork, grating, floor plate, handrails, girts, cladding and a range of process platework. We also managed civil works carried out by one of Walz Group’s trusted subcontractors.

Mechanical works included installation of cyclones, coarse coal centrifuges, product screens, conveyor idler replacements, jib crane, and various pumps and drives.

Additional works comprised miscellaneous concreting, demolition of existing structures, and the construction of various ground slabs, suspended slabs and equipment plinths.

Curragh – CPP1 Tailings Retreat Circuit

After working together successfully on previous projects, Wesfarmers Curragh Pty Ltd (WCPL) engaged Walz Group to support the installation of a new tailings retreat circuit to the Coal Preparation Plant 1 (CPP1) at its Blackwater mine in Queensland. We’ve worked at Curragh before and have gained a solid understanding of the mine’s operational requirements. For this upgrade project, we performed all structural, mechanical and piping, and electrical installation components. We outsourced the electrical works component to a trusted subcontractor. Our fabrication workshop in Gladstone produced the custom pipework, handrails, and platework for the project. Blasting and painting was also performed by Walz in our purpose built facility.

After commissioning, the upgrade increased the plant’s yield by around two percent, delivering approximately 30 tonnes per hour of additional secondary product.

The works incorporated three main areas of the tailings retreat circuit — the Eastern building, the Western building and the secondary product conveyor. A new clarified water pump was also installed to supply the additional demand from the new circuit.

Connecting to the eastern side of CPP1, the Eastern building houses the tailings cyclones, sieve bends, spirals feed sump, and the relocated spirals feed pump.

The Western building connects to a previously existing structure and incorporates the spiral banks, spirals product sump and pump, spirals product cyclone cluster, fine coal centrifuge, and the reject sump and pump.

The secondary product conveyor is fed by the centrifuge, running from the new Western building to transfer product onto the existing steaming coal conveyor.

Cement Australia – Heat Exchanger Duct Replacement

Cement Australia’s operations in Gladstone incorporate Australia’s largest cement kiln, capable of producing more than 1.6Mtpa of cement.

Early in 2017, it was identified that the heat exchanger duct between the clinker cooler and the inlet to heat exchanger no.1 (HE1) had reached the end of its life, and was significantly impacting on plant production. Cement Australia engaged Walz Group to replace the equipment to return the kiln performance to full capacity. The project required us to remove and replace the failing heat exchanger, ductwork, inlet chamber, associated supports, and specified tubes during a time critical shutdown.

We utilised our dedicated fabrication facility to manufacture all the ductwork, inlet chamber, and the associated supports and components. We also applied protective coating as required. Prior to the shutdown for the replacement works, we reinforced the plant foundation and structure to ensure it could accommodate additional loads.

Our comprehensive plant and equipment fleet was invaluable for this project, which required craneage and scaffolding to remove and replace the existing structure.

BMA Hay Point – Stacker Reclaimer SR1 & SR2 Refurbishment

When the existing stacker-reclaimer stockyard machines (SR1 and SR2) at the Hay Point coal terminal started to approach the end of their life, BMA commenced the process of replacing them. With an anticipated lead time of two years for the new equipment to be manufactured and shipped to Australia, the machines needed work to be kept operational until the replacements arrived.

Walz Group was contracted to dismantle both stacker-reclaimers down to the fixed cone to undertake structural integrity repairs. This would extend the life of both machines for the interim lead time of their replacements. The works involved removal of mast, pendants, bucket wheel boom, counterweight arm, counterweight box and slew cone.

The machines were then rebuilt with new slew cone, new counterweight assembly and refurbished bucket wheel boom. Both machines were jacked up to clear the rails to remove all bogies, which had to be refurbished and machined to suit the new rail profile.

Our fabrication workshop and protective coatings workshops Gladstone were instrumental in the repair and refurbishment of existing componentry.