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Stainless Steel Shines in Perth's Elizabeth Quay

12 December 2016

The successful collaboration of ASSDA members and their expertise in the extensive use of stainless steel has been integral to bringing Perth’s iconic and most complex bridge to life.

The Elizabeth Quay Pedestrian Bridge was constructed by DASSH, a joint venture between Decmil, Structural Systems and Hawkins Civil, and is a key feature of the Elizabeth Quay mixed-use development project core to revitalising Perth’s CBD.

Designed and engineered by Arup, the cable-stayed suspension bridge features a leaning double arch, is 22m high, 5m wide and is suspended over the inlet of the Swan River with a clearance of 5.2m from the water. The 110m long meandering pedestrian and cyclist bridge allows for continuous movement around the Quay, connecting the new promenades, an island and ferry terminal.

Stainless steel reinforcement plays a vital structural role in the bridge, with ASSDA Sponsor Valbruna Australia supplying approximately 89 tonnes of 2304 grade Reval® in 12, 20, 25 and 32mm reinforcement bar for the three concrete river piers. The reinforcement bar diameters originally specified were not available locally and so the design was modified to accommodate what was ex-stock in Australia to minimise construction downtime.

Installed exclusively in the splash zones of the concrete piers, stainless steel reinforcement was specified to resist corrosion attack and prevent concrete spalling. In addition, the overall mass of the concrete piers had to be minimised in order to support and achieve the sleek, sinuous design of the almost 200 tonne arches.

Reduction in concrete mass decreases the overall protection of the installed reinforcement bar, resulting in stainless steel as the material of choice to achieve the slimmer river piers and meet the demands of the architectural design.

During the grade selection process, grade 2304 lean duplex stainless steel was also deemed the most cost effective option to reduce ongoing maintenance costs and deliver the expected 100-year service life of the structure.

Visually, stainless steel is also featured in the key design elements of the bridge, including the handrails, balustrades, support posts, mesh barriers, kerbing, fascia panels and kick rail stations. Local jarrah timber decking and decorative feature lighting was used to complete the durable and low-maintenance walk and cycle way.

ASSDA Member Stirlings Australia supplied over 60 tonnes of stainless steel for the bridge project, including 111 wire mesh panels, over 300m of 50.8mm x 3mm round tube in a 320 grit finish to support the mesh panels, welded pipe for the handrails and balustrades, and 2205 and 316/316L grade plate in 6mm and 10mm. An additional 52 tonnes of 316/316L and 8 tonnes of 2205 grade stainless steel plate was supplied and laser cut in-house by Stirlings Australia using their 6000mm x 2000mm laser cutting machine for large-format materials.

Furthermore, Stirlings Australia supplied 7 tonnes of stainless steel channel and angle bar for the architectural elements and structural sections of the quay’s new ferry terminal.

ASSDA Sponsor Vulcan Stainless also supplied the project with over 50 tonnes of laser cut 2205, 316 and 316L grade stainless steel. Polished 2205 grade 3mm stainless steel plate was supplied via its Sydney service centre, cutting approximately 10 tonnes of coil to length, which was then laser cut to size and polished to the specified No. 4 finish prior to delivery. Upright and support pieces for the balustrading were also laser cut and supplied from Vulcan Stainless’ Sydney and Perth service centres using 316 grade 12mm and 316L grade 16mm stainless steel plate.

The 25mm thick pieces were cut using Vulcan Stainless’ in-house 8kw Trumpf Laser, the only machine in Western Australia able to laser cut at this thickness including holes.

Both Stirlings Australia and Vulcan Stainless also supplied laser cut 316/316L grade stainless steel plate for the planter beds that formed part of the landscaping around the Elizabeth Quay precinct.

ASSDA Member Unifab Welding was contracted to fabricate and install over 60 tonnes of stainless steel for the visual elements of the pedestrian bridge as supplied by Stirlings Australia and Vulcan Stainless.

Over 60 different individual balustrade sections each at 1800mm tall were fabricated to allow for the shape and movement of the bridge. Manufactured in compliance with AS/NZS 3992 and ASME 9, Unifab Welding used gas manual arc welding (GMAW) and gas tungsten arc welding (GTAW) techniques to fabricate the various sections.

To meet strict deadlines, all kerbing pieces were welded together using 8mm stainless steel flat bar to replicate the originally specified 300x100x8mm rectangular hollow sections (RHS), a product that was not locally available off-the-shelf. The kerbing pieces were also polished back to a 320 grit and No. 4 finish.

Aside from the wire mesh, all stainless steel components for the bridge were polished to Ra<0.5 and then electropolished prior to installation to provide maximum corrosion resistance in the salt-water environment.

A key architectural feature of Elizabeth Quay, the pedestrian footbridge was opened to the public in January 2016. It exudes in quality, aesthetic appeal and durability with its extensive use of stainless steel, and is certain to provide the structural and material performance required to stand the test of time.

Offering 360-degree views, the bridge is an exciting addition to Perth’s CBD and provides increased opportunity for locals and tourists to interact with the Swan River and reinvigorated waterfront destination.

This article in Australian Stainless Magazine Issue 58 (Summer 2016/17).

A Walk to Remember

12 June 2015

The spirit of the Anzacs is evoked in a new architecturally stunning, stainless steel walkway that unfolds around Newcastle’s cliffs and links Strzelecki Lookout to Bar Beach.

 The much-anticipated Newcastle Memorial Walk opened on 24 April 2015 on the eve of the Anzac centenary, and features spectacular 360-degree views of Newcastle city and coastline.

The 450m raised walkway forms part of Newcastle City Council’s ‘Bathers Way Project’, a $29 million foreshore development and revitalisation program to link Merewether Beach with Nobby Beach via a coastal walk. The total cost of the walkway was $4.5 million, $3 million of which was contributed by BHP Billiton to mark their 100-year anniversary since the commencement of steel making in the Hunter region.

In commemoration of the Anzacs the walkway features silhouettes of soldiers, laser cut from 10mm thick weathering steel, specified to withstand the coastal wind load. These silhouettes are engraved with 3,860 family names of almost 11,000 known Hunter Valley men and women who served in the Australian Imperial Force, Royal Australian Navy, Australian Army Nursing Service and British and Commonwealth forces during World War 1 from 1914-1918.

EJE Architecture carried out the detailed design work, and lead architect Barney Collins said the historical significance of the project site inspired the walkway’s sinusoidal design.

“During the design phase, we looked at the history of the site and build location next to Memorial Drive, which was originally constructed in 1922 to pay tribute to the soldiers who fought in World War I,” Collins said.

“The design concept of what is commonly known as ‘the wave effect’ was drawn on the fact that DNA was used to identify the human remains of soldiers, and this process stood as the connection between the soldiers and their families.”

Constructed by Waeger Constructions and engineered by Northrop Engineers, the walkway has a structural design life of 70 years, as required by Newcastle City Council. Grade 316L stainless steel was specified due to its sustainable, corrosion resistance and ductile properties. The cliff top location of the walkway overlooking the Pacific Ocean was also a determining factor given the high wind and salt exposure.

ASSDA Sponsor Atlas Steels supplied 64 tonnes of stainless steel for the walkway including DN150 x 10.7mm, DN125 x 6.5mm, and DN65 x 5.1mm wall pipe; 200mm x 100mm x 6mm rectangular hollow sections and 100mm x 100mm x 5mm square hollow sections for the bridge section frames; and 16mm diameter round bar and 50 x 2mm and 50 x 3mm round tube for the handrails and balustrades.

Good scheduling and planning ensured on-time delivery of the stainless steel over a period of 14 weeks, which was sourced from three overseas mills. Positive material identification (PMI) testing was performed by the mills on all stainless steel supplied to ensure the specified grade of 316L was delivered.

Fabricated and installed by ASSDA Member and Accredited Fabricator SGM Construction & Fabrication, the 160m of stainless steel bridge sections consist of eight, 20m single spans (four under trusses and four over trusses) each weighing 6.5 tonnes. The frame of each section is fabricated from 12 square hollow sections welded to two rectangular hollow   sections, and the walking surface is laid over the frame. On either side of the truss, the wave-like effect was created by bending and rolling wall pipe to sweep above the frame for the over trusses and below the frame for the under trusses.

Seven Y-shaped precast concrete pylons up to 8.8m high and 3.4m wide, and two abutments, support the bridge sections of the walkway that reach up to 9m above the ground.

The decking of the walkway was laid with fibre-reinforced plastic, and being a non-structural component, was specified with a 44-year design life. The safety aspects of the bridge are completed with hand railings, which are welded on to the bridge trusses inside the curved pipe sections.

Over 760m of handrails and 600m of vertical balustrades cover the length of the bridge, specified with a maximum Ra value of 0.5. ASSDA Member Australian Pickling & Passivation Service was contracted to electropolish the balustrades and pickle and passivate the completed bridge sections. A purpose-built electropolishing unit, consisting of six baths, was set up to handle and achieve the specified finish of the 1.5m high x 6m long balustrade panels each weighing 180kg.

With an allotted fabrication period of only four months, SGM Fabrication & Construction manufactured the bridge sections using its 2000m2 workshop to full capacity to meet the critical deadline for Anzac Day.

As the walkway runs parallel to Memorial Drive, the main thoroughfare from King Edward Park to Merewether Beach, the erection of the pylons and installation of the bridge sections took place only during a 10-hour window over two nights to avoid prolonged temporary road closures.

Coastal undermining was a challenge for the structural engineers, however good design and construction ensured environmental protection of the sensitive coastal site to minimise erosion.

Mr Collins said the key to the project’s cost control and overall success was the engagement of local contractors.

“The direct involvement of each contractor’s Directors ensured seamless communication and full control of each project phase. The walkway is already an icon for Newcastle, and everyone who has worked on the project is thrilled over its success,” Collins said.

More than two million people visit Newcastle’s beaches every year, and the Newcastle Memorial Walk is already one of Australia’s most remarkable coastal walkways and a significant World War I tribute.

  

This article is featured in Australian Stainless Issue 55 (Winter 2015).

Images courtesy of Bryce Thomas.

Stainless Steel in Western Australia Subsea Applications

12 June 2015

Stainless steel is the material of choice for subsea hydraulic and control line applications because of its excellent corrosion resistance, material strength benefits and weldability.

 Subsea production in the oil and gas industry involves offshore, in situ equipment to facilitate the exploration, development, production and transportation of energy reserves from underwater fields. It is a viable form of oil and gas production, providing economic, productivity and environmental benefits.

Perth-based ASSDA Member and Accredited Fabricator Diverse Welding Services (DWS) recently completed detailed design and fabrication works on two major subsea projects operated by multinational oil and gas exploration and production companies.

Apache Corporation’s Coniston and Novara Redevelopment Project, completed in February 2014, is a subsea oil field located 65km north of Exmouth. The project involved an upgrade to the Ningaloo Vision floating production, storage and offloading (FPSO) unit and development of the neighbouring Coniston and Novara oil fields, which links these fields into the existing Van Gogh manifolds via dual production flow lines. The equipment operates in water 340 to 400m deep.

DWS was contracted to detail the design, fabrication, installation and NDT testing of the small-bore hydraulic control and chemical injection lines for five subsea production manifolds.

2,380m of 316L stainless steel wall tube in various sizes ranging from 0.375” OD x 0.083” up to 1.000” OD x 0.156” was used, plus 30m of Inconel 625 0.750” OD x 0.134” wall tube.

Chevron Australia’s Wheatstone Project, located 12km west of Onslow on the Pilbara coast of Western Australia, is one of Australia’s most significant LNG projects. Currently in progress and at almost 60% complete, it will become the country’s first third party natural gas hub. DWS was contracted to fabricate, install and test small-bore tubing and free issue components to Multiple Quick Connect (MQC) plates. The main free issue components consisted of logic caps, cobra heads, single line couplers and acid injection items requiring small-bore interconnecting tubing on four MQC plates serving the subsea isolation valves (SSIV) for the 44” trunkline, 24” and 14” flowlines, and the 18” APACHE/KUFPEC line.

SAF2507 super duplex stainless steel was used for the MQC plates including over 80m of 0.625” OD x 0.083” wall tube, 20m of 316L 0.375” OD x 0.083” wall tube and 130 Swagelok 90° elbow butt-weld fittings. The MQC plates were fabricated by PT Profab Indonesia, then shipped to DWS in Perth for detailed fit-out using autogenous orbital welding processes. After testing, the completed MQC plates were shipped back to PT Profab Indonesia for installation into the SSIV manifolds.

All welding by DWS for both projects was completed using an autogenous orbital welding process, specified by the clients for the small-bore hydraulic tubing welding due to its excellent control of welding variables, repeatability of application and maximisation of corrosion resistance of exotic materials. DWS produced high quality welds that when tested under the G48 Method A – Pitting Resistance Testing, proved resulting weight loss to be less than 0.36g/m2.

Orbital welding is an automatic method of Tungsten Inert Gas (TIG) welding of thin tubes, usually without filler wire. Its advantages are a uniform weld profile and excellent gas shielding giving minimal heat tint. The ends of the tube are prepared and clamped in an enclosed head, which is flushed with external shielding and internal purging gas – usually argon, although gas mixtures can be used. The cycle starts by striking the arc and proceeds as the head slowly rotates around the tube. A specific weld head can deal with several diameter tubes. The weld is usually in the centre of the head, although heads are available for offset joins used with joints to elbows or valves.

DWS completed 1200 welds for the Coniston and Novara Redevelopment Project and 204 welds for the Wheatstone Project, which passed 100% radiographic/liquid penetrant testing in accordance with ASME B31.3 NFS. The excellent gas and heat input control of the orbital welding produced internal surfaces that did not require post-weld cleaning. The external surfaces around the welds were abrasively treated as required for aesthetics reasons.

The DWS facility includes five autogenous welding machines complimented with seven welding heads of assorted ranges allowing DWS to complete weldments from 0.25” OD to 6” OD tube/pipe schedules as required for these project works. This coupled with their extensive range of other qualified weld procedures for this process allows DWS to meet clients’ stringent fabrication, application and quality specifications.

         

This article is featured in Australian Stainless Issue 55 (Winter 2015).

Riverwalk Reborn

21 October 2014

Brisbane's New Farm Riverwalk is one of the city's beloved icons. Originally constructed in 2003, the Riverwalk was used daily by over 3000 cyclists, pedestrians and runners before it was washed away during the 2011 floods.

After a construction period of nearly 18 months, Brisbane City Council’s re-imagined New Farm Riverwalk has now opened to the public, connecting New Farm to the Brisbane City via the Howard Smith Wharf Precinct.

Engineered by Arup, the Riverwalk has a design life of 100 years and sits 3.4m above mean sea level on robust piles.

Critical to its design and life expectancy is the extensive use of stainless steel for both structural and aesthetic purposes.

Brisbane City Council’s two key objectives of the project were to achieve a low maintenance, durable structure while achieving high aesthetic qualities. Stainless steel was deemed suitable to achieve both objectives while also providing the necessary strength required.

Key design elements featuring stainless steel include balustrades, skate stops, help point enclosures, light posts, signage, electrical enclosures, deck furniture and bins at the node structures. For additional durability, stainless steel reinforcement conforming to BS10088 and BS 6744:2001 was used in the soffit of the precast concrete girders where the structure could be subject to wetting and chloride contamination in the future.

Constructed by John Holland, the project involved a high level of collaboration between multiple suppliers and fabricators to meet the exacting demands of the specification.

John Holland Project Engineer Cameron Pahor said one challenge was programming works in accordance with project specifications to reduce contamination between carbon steel and stainless steel, both of which were used within the precast concrete girders incorporated into the Riverwalk.

Modelling of the reinforcing in 3D by Vectors Computer Aided Drafting also meant exact dimensions were ascertained, reducing waste of stainless steel reinforcing.

ASSDA Sponsor Valbruna Australia Pty Ltd’s Queensland construction division was contracted to supply 385 tonnes of stainless steel reinforcing bar, with The Australian Reinforcing Company (ARC) sub-contracted to schedule, cut and bend the rebar in a specifically prepared quarantine location to prevent processing and storage contamination issues.

Valbruna Special Products Manager Scott Ford said the majority of the rebar (in diameters ranging from 12mm to 40mm) was produced to precise precast tolerances predominantly using Reval® special Grade AISI 2304 (1.4362). Grades 2205, 316L and 304L were also used due to the unexpected increase in tonnage required: nearly 40% more than original project calculations was required, making the Riverwalk the largest use of stainless steel rebar in Australia to date.

Mr Ford said stainless steel rebar ensured the Riverwalk met the required 100 years life cycle, while minimising ongoing maintenance costs.

“Using stainless steel rebar ensures that a landmark structure such as the Riverwalk is kept open to the public rather than lengthy maintenance closures due to corrosion issues,” he said.

Down time was also minimised during construction, with Valbruna holding extensive stocks on the floor in both Italy and Australia of stainless Reval® rebar, enabling delivery to site within 48-72 hours of final approval of drawings. Manual templates were produced for many of the bars to ensure the accuracy of the bends and eliminate site down time.

Minimising maintenance for the visual elements of the Riverwalk was also a priority. To this end, ASSDA Sponsor Midway Metals supplied 275 tonnes of grade 316 stainless steel and two tonnes of welding consumables for the construction of around 1900m of balustrading. Midway also supplied 100 litres of Avesta pickling gel that was used to passivate all welds on the balustrades.

Midway Metals Brisbane Branch Manager Sean Lewsam said some of the specified handrail sizes were not available in Australia (e.g. 150x50x6mm rectangular hollow section or RHS) and had to be air freighted in to meet strict deadlines.

Midway supplied the project with 3,522 metres of RHS, 14,500 metres of round bar, 1,924 metres of HRAP (hot rolled, annealed, pickled) flat bar, 1,500 metres of flat bar from their slitting and flat bar machines, and 2,000 metres of mirror tube, storing the material in a dedicated holding area for the duration of the project.

Specific-sized Grade 316 plates were acquired (132 tonnes in total ranging from 10mm to 16mm) to minimise off cuts and wastage during the plasma cutting of stiffener plates, 1500 base plates and 1000 staunchions for the balustrades. Around 26 tonnes of laser cut profile plates ranging from 5mm to 20mm were also supplied.

ASSDA Member Southern Stainless was contracted to fabricate and install three different types of balustrading (solid uprights, mesh wire and glass infill), as well as the other visible stainless steel elements of the project using the stainless steel and welding consumables supplied by Midway Metals.

Southern Stainless General Manager Matthew Brown said all stainless steel components were manually polished to a 600 grit finish prior to assembly and welded in compliance with AS1554.6. After fabrication, the 960 balustrades panels (each weighing between 180 and 220kg) were electropolished in-house to Ra<0.5 and then hand polished with silicone-based polish prior to being wrapped and delivered to site for installation. The end product is both visually appealing and certain to stand the test of time.

Strength testing was undertaken for the balustrade/girder connections to ensure the stainless steel couplers, bolts and ferules (supplied by ASSDA Member Ancon Building Products) would not damage the cast-in items during a flood occurrence.

Riverwalk’s robust design makes it resilient to future flood events. The opening span has been relocated to reduce the likelihood of debris getting caught on the structure, and some elements have been designed to collapse in extreme events (rather than withstand the flood waters), reducing the force on the piles.

With the re-imagined Riverwalk now a fixture on the Brisbane’s riverscape once again, residents and visitors can look forward to enjoying the unique experience that Riverwalk offers well into the future.

This article is featured in Australian Stainless magazine issue 54, Spring 2014.


Posted 3 May 2012

The Fibonacci spiral and the intersecting spines of a nautilus shell have inspired an impressive 23m high stainless steel sculpture at Kangaroo Point Park overlooking Brisbane's river.

Designed by UK public space artist Wolfgang Buttress, Venus Rising features 10,790 individual welds and over 7km of grade 316 and 2205 duplex stainless steel tube, pipe and round bar supplied by ASSDA Sponsor, Sandvik.

Having worked with stainless steel for over 25 years, Buttress said that the material’s strength, ability to look good over time with minimal maintenance, and the flexibility of finishes works well both practically and aesthetically.

“The variety of finishes which can be achieved with stainless steel through polishing, glass blasting and heat treatment is great. The material needs to be strong, resilient and look as good in 50 years as it does on installation,” Buttress said.

Initial fabrication works took place in the UK before being transported to Brisbane for final assembly. D&R Stainless, an ASSDA member and Accredited Fabricator, continued the fabrication of the 11.5 tonne spire-like sculpture over a period of six weeks. It used the artistic vision of Buttress, as well as renders and 3D models to guide the assembly of the sculpture.

The central design of the sculpture was to create a piece of artwork that was visibly prominent and exemplified strength, elegance and weightlessness. The sculpture features a criss cross ladder-type construction with heavy wall pipes that gently twist to create a hollow spiral. Visitors can enter the sculpture at the base level and gaze up at the sky through an opening at the top.

“I wanted to make connections between the Brisbane River and the sky above. It was important to me that the sculpture works on an intimate scale as well as being seen from afar,” Buttress said.

“Visually, the most challenging part of the project was to try and maintain harmony between form and sculpture. I wanted the piece to have a delicacy but also be strong.”

The main structure of the sculpture features 2205 duplex stainless with cladding tubes at the bottom of the structure starting at 12mm, ascending to 8mm and 10mm tube through the middle and 6mm and 8mm solid round bar at the top. Tubes were supplied in 6m lengths and welded together to create continuous lines of tubing for the stretch of the sculpture.

12mm thick stainless steel tubes in the skeleton of the structure extend about half way up and were heat treated in a stress relieving oven. This transformed the colour of the steel into a golden hue to create a contrast effect in the sculpture.

“We cut 30 to 40 small lengths of stainless steel at various thicknesses and baked them at different temperatures from 100˚ C up to 400˚ C. After comparing the various shades and hues, I chose the golden colour in the end which required heating to around 300˚ C,” Buttress said.
Grade 316 polished stainless steel tubing was used for the middle cladding on the exterior of the structure.

Stainless steel rings were laser cut from LDX 2101 plate in various thicknesses from 20mm down to 3mm, and welded to the body of the sculpture to create an intricate lace-like effect.

The main structure was bead blasted to create a uniform finish and all tubes were chemically cleaned.

Both TIG and MIG welding processes were used, with both solid wire and flux cord used in the MIG welding technique. Di-penetration testing was conducted offsite on the welding of the body of the sculpture to ensure structural integrity.

D&R Stainless director Karl Manders said that while fabricating stainless steel was familiar territory, the application was different and stimulating.
“We found the project intriguing because while we were producing a delicate structure, the core components of the fabrication were quite complex. Our business focuses on heavy industrial applications, and the materials we used for Venus Rising are those used in the heart of the mining and petrochemical industries,” Manders said.

“The experience of this project was intense but satisfying. We made Wolfgang’s vision come to life.”

Buttress said D&R Stainless was a perfect fit for the project and they will also be on board for an upcoming sculpture for The University of Canberra.

“Their understanding of the properties of stainless steel was second to none and their craftsmanship exemplary. It was great to witness such pride in their workmanship,” Buttress said.

Commissioned by the Queensland Government, Venus Rising was selected in a public vote as the winning design from over 60 submissions and was unveiled in late January 2012.

Photographer: David Sandison. Images courtesy of The State of Queensland, Department of Housing and Public Works.

This article is featured in Australian Stainless magazine, issue 51.

The Go-Between Bridge


Posted 3 May 2012

With 14,000 vehicles crossing Brisbane's Go-Between Bridge every day, stainless reinforcement is playing a vital structural role on Brisbane's first inner city bridge in over 40 years.

Formerly known as the Hale Street Link, the Go-Between Bridge connects Merivale and Montague Streets in West End to Coronation Drive and the Inner City Bypass in Milton.

Constructed as part of the Brisbane City Council’s TransApex plan, the Go-Between Bridge was designed to improve cross-river accessibility, reduce inner city traffic congestion, increase accessibility to Brisbane’s recreational and cultural precincts and cater for future residential developments in West End and South Brisbane.

The $338 million project commenced in 2008 and was built by the Hale Street Link Alliance (Bouygues Travaux Publics, MacMahon Holdings, Seymour Whyte Holding and Hyder Consulting).

The cantilever, box girder bridge stretches 274 metres over the Brisbane River and was built using stainless steel reinforcement with concrete foundations. Featuring a dedicated pedestrian and cyclist pathway, the Go-Between Bridge is 27 metres wide, with the main span measuring 117 metres.

ASSDA sponsor Valbruna Australia supplied 80 tonnes of grade 316L/1.4462 Reval® stainless steel in 12mm, 16mm, and 24mm reinforcement bar, which was used for the two major pile caps and north abutment of the bridge.

Valbruna Australia’s Managing Director, Ian Moffat, said stainless steel was specified for the critical elements of the bridge to minimise life cycle costs, improve structural integrity and corrosion resistance.

“Particularly being located in a marine environment, Reval® stainless in reinforced concrete is ideal to resist chlorides and pitting corrosion; it has an expected service life of 100 years in concrete,” Moffat said.

By specifying stainless, the designers were able to reduce the area in which stainless rebar was used in the structure because of its tensile strength being higher than carbon steel. In addition, using stainless steel reinforcement in concrete structures is stronger than carbon steel and will prevent material fatigue ensuring longevity for public infrastructure.

Moffat said Valbruna had 30% of stainless rebar already in stock, with the rest of the material having been shipped from their warehouse in Dubai and direct from their mill in Vicenza, Italy.

“Between the three locations, we were able to supply the stainless steel early and well within the specified timeframe,” Moffat said.
All Reval® stainless steel was produced and tested on site at the Acciaierie Valbruna S.p.A mill in Italy and manufactured to ISO 9001:2008 norms as certified by Lloyd’s Register Quality Assurance.

The Reval® stainless rebar was delivered to Neumann Steel in Currumbin for scheduling, cutting and bending.

A cut-to-length shear line machine was used, as well as a level off-coil machine to cut and bend the material into the finished product. All machines were cleaned before use to remove dust and carbon steel residue to avoid contamination of the stainless steel.

Neumann Steel’s Reinforcing Scheduler, Greg Prider, said the project was extremely complex and difficult to schedule.
“As the precast concrete units were manufactured at another site, we had tight tolerances to work with. It was critical to be precise in cutting and bending the stainless rebar to avoid unnecessary additional costs,” Prider said.

Following six weeks of scheduling, the stainless rebar was sent to the Brisbane Barge Berth, where precasting of the concrete units were assembled before transporting the modules direct to site by barge for installation.

Named after iconic Brisbane rock band The Go-Betweens, the Go-Between Bridge was completed and officially opened to traffic in July 2010.

This article is featured in Australian Stainless magazine, issue 52.


Posted 3 May 2012

Stainless is a key feature in the urban design and revamp of one of the Gold Coast's most iconic and vibrant tourist destinations.

The $25 million Surfers Foreshore Project was commissioned by the Gold Coast City Council (GCCC) to redevelop the beachfront area between Laycock Street and View Avenue in Surfers Paradise.

Aimed at improving infrastructure and visitor recreation, the new promenade features new lifeguard towers, amenity blocks, beach shelters, picnic areas with barbeques, and increased pedestrian and disability access to the beach.

Managing Contractor Abigroup Contractors Pty Ltd appointed ASSDA member and Accredited Fabricator J&T Mechanical Installation to fabricate and install the stainless steel architectural handrails and balustrades across stages 1, 2 and 3.

Trent Todd, J&T Mechanical Installation’s Director, said that with the handrails and balustrades being installed less than 30m from the shoreline, stainless steel was the only choice to withstand the harsh coastal environment to help resist tea staining and ensure long-term durability and performance.

A 2009 GCCC study in affiliation with Griffith University saw the GCCC adopt stainless steel as the default specification for structures with a design life of more than 19 years in foreshore zones.

This followed research results showing the material required lower maintenance and was the most effective in life cycle costs when compared with hot dipped galvanized (HDG) steel, paint systems and duplex systems using both HDG and paint.

At a total cost of approximately $80,000, the stainless steel handrails and balustrades span 1300m across the esplanade that fronts Surfers Paradise Beach.

Grade 316L stainless steel was specified for these elements of the project, which included 36 sheets of 10mm thick plate measuring 1500mm x 3000mm supplied by ASSDA member Allplates. ASSDA Sponsor STM Tube Mills Pty Ltd supplied 1300m of 50.8mm x 1.6mm thick tube. Another 3500m of 1/4” wire was also sourced for the balustrading.

All the flat and tube components including 124 stanchions were laser cut and folded by Allplates.

Stanchions and base plates were machine polished to 600 grit by ASSDA member and Accredited Fabricator Minnis & Samson to give the stainless steel an even polish and the stanchions a square edge. The stanchions were electropolished before being delivered back to J&T Mechanical Installation’s workshop for assembly.

J&T Mechanical Installation fabricated the top (50.8mm x 1.6mm tube) and bottom (folded channel, 4mm thick) rail frames with two vertical 16mm diameter solid round bar intermediate supports. Infill wires at 6.4mm diameter were positioned with swage fittings and lock nuts on each end to construct the vertical balustrades.

On site, J&T Mechanical Installation completed civil works prior to installation, including pre-drilling with the fasteners for the base plates to which the stanchions were then bolted. The rail frames were welded to the stanchions in 2.1m sections.

Following installation, a proprietary stainless steel cleaner was applied to remove any oxides, and a mild cleaner was followed to provide surface protection and inhibit corrosion.

Architectural feature lighting was installed to illuminate the pedestrian walkways at night.

The Surfers Foreshore Project was completed in April 2011 and today continues to thrive as the Gold Coast’s most popular entertainment precinct where city meets the surf.

Images courtesy of Allplates.

This article is featured in Australian Stainless magazine, issue 51.


Posted 17 May 1999

If a job requires greater corrosion resistance than grade 304 can provide, grade 316 is the 'next step up'. Grade 316 has virtually the same mechanical, physical and fabrication characteristics as 304 with better corrosion resistance, particularly to pitting corrosion in chloride environments.

Grade 316 (U NS S31600) is the second most popular grade accounting for about 20% of all stainless steel produced.

This article follows on from "304 -the place to start" in Issue 10 which is also available on ASSDA's website at www.assda.asn.au

COMPOSITION
Table 1 compares three related grades - 316, 316L and 31 6H.

Grade 316L is a low carbon 316 often used to avoid possible sensitisation corrosion in welded components.

Grade 316H has a higher carbon content than 316L, which increases the strength (particularly at temperatures above about 500°C), but should not be used for applications where sensitisation corrosion could be expected.

Both 316L and 316H are available in plate and pipe, but 316H is less readily available ex-stock. 316L and 316H are sometimes stocked as standard 316 (test certificates will confirm compliance with the 'L' or 'H' specification).

CORROSION RESISTANCE
Grade 316 has excellent corrosion resistance in a wide range of media. Its main advantage over grade 304 is its increased ability to resist pitting and crevice corrosion in warm chloride environments. It resists common rusting in virtually all architectural applications, and is often chosen for more aggressive environments such as seafront buildings and fittings on wharves and piers. It is also resistant to most food processing environments, can be readily cleaned, and resists organic chemicals, dye stuffs and a wide variety of inorganic chemicals.

In hot chloride environments, grade 316 is subject to pitting and crevice corrosion and to stress corrosion cracking when subjected to tensile stresses beyond about 50°C. In these severe environments duplex grades such as 2205 (UNS S31803) or higher alloy austenitic grades including 6% molybdenum (UNS S31254) grades are more appropriate choices.

The corrosion resistances of the high and low carbon versions of 316 (316L and 316H) are the same as standard 316.

HEAT RESISTANCE
Like grade 304, 316 has good oxidation resistance in intermittent service to 870°C and in continuous service to 925°C. Continuous use of 316 in the 425-860°C range is not recommended if subsequent exposure to room temperature aqueous environments is anticipated, but it often performs well in temperatures fluctuating above and below this range.

Grade 316L is more resistant to carbide precipitation than standard 316 and 316H and can be used in the above temperature range. However, where high temperature strength is important, higher carbon values are required. For example, AS 1210 Pressure Vessels Code limits the
operating temperature of 316L to 450°C and restricts the use of 316 to carbon values of 0.04% or higher for temperatures above 550°C. 316H or the titanium-containing version 316Ti can be specified for higher temperature applications.

316 has excellent toughness down to temperatures of liquefied gases and has application at these temperatures, although lower cost grades such as 304 are more usually selected for cryogenic vessels.

PHYSICAL AND MECHANICAL PROPERTIES (see Tables 2 and 3)
Like other austenitic grades, 316 in the annealed condition is virtually nonmagnetic (ie. very low magnetic permeability). While 304 can become significantly attracted to a magnet after being cold worked, grade 316 is almost always virtually totally non-responsive. This may be a reason for selecting grade 316 in some applications.

Annealing (also referred to as solution treating) is the main heat treatment carried out on grade 316. This is done by heating to 1,010-1,120°C and rapidly cooling - usually by water quenching.

FABRICABILITY
316 can be deep drawn without intermediate heat softening enabling it to be used in the manufacture of drawn stainless parts, such as sinks and saucepans. However, for normal domestic articles the extra corrosion resistance of grade 316 is not necessary. 316 is readily brake or roll formed into a variety of other parts for application in the industrial and architectural fields.

Grade 316 has outstanding weldability and all standards welding techniques can be used. Although post-weld annealing is often not required to restore 316's corrosion resistance (making it suitable for heavy gauge fabrication) appropriate post-weld clean-up is recommended.

Machinability of 316 is lower than most carbon steels. The standard austenitic grades like 316 can be readily machined if slower speeds and heavy feeds are used, tools are rigid and sharp, and cutting fluids are involved. An 'improved machinability' version of 316 also exists.

COST COMPARISONS
The guidelines in Table 4 are approximate 'first cost' comparisons for sheet material in a standard mill finish suitable for construction projects. The appeal of stainless over its first cost competitors dramatically increases
when lifecycle costs are considered.

FORMS AVAILABLE
Grade 31 6 is available in virtually all stainless product forms including coil, sheet, plate, strip, tube, pipe, fittings, bars, angles, wire, fasteners and castings. 316L is also widely available, particularly in heavier products such as plate, pipe and bar. Most stainless steel surface finishes, from standard to special finishes, are available.

APPLICATIONS
Typical applications for 316 include boat fittings and structural members; architectural components particularly in marine, polluted or industrial
environments; food and beverage processing equipment; hot water systems; and plant for chemical, petrochemical, mineral processing, photographic and other industries.

Although 316 is often described as the 'marine grade', it is also seen as the first step up from the basic 304 grade.

Alternative grades to 316 should be considered in certain environments and applications including:

• strong reducing acids (alternatives might be 904L, 2205 or a super duplex grade),
• environments with temperatures above 50-60°C and with chlorides present (choose grades resistant to stress corrosion cracking and higher pitting resistance such as 2205 or a super duplex or super austenitic), and
• applications requiring heavy section welding (316L), substantial machining (an improved machinability version of 316), high strength or hardness (perhaps a martensitic or precipitation hardening grade).

 

This technical article featured in Australian Stainless magazine - Issue 13, May 1999.


Posted 17 May 1999

The devastation of the 1989 Newcastle earthquake resulted in a revision of standards specifying building materials and products to be used in differing environments.

One of the products that came under close scrutiny was wall ties (also known as brick ties).

Assessment of the damage after the earthquake found that many walls had 'peeled away' from building structures due to deteriorated wall ties.

A wall tie connects masonry to the structural backing which supports the wall. The most common wall ties are manufactured out of galvanised steel.

Australian Standard AS 3700 - 1998 revised the conditions under which wall ties are used and made recommendations about the types of material that should be used in different environments.

The Standard specifies that 316 or 316L stainless steel wall ties should be used in 'R4' category environments. These are severe marine environments, usually up to 1 00 metres from a nonsurf coast or one kilometre from a surf coast, where the highest airborne salinity level at the exterior of the masonry is 300 g/m2/day.

In such environments the chlorides in the air make it highly corrosive and not suitable for wall ties manufactured from materials that are susceptible to corrosion.

However this requirement is the subject of debate, with some specialists suggesting that corrosive environments stretch well beyond the distances specified in the Standard.

The use of stainless steel wall ties as suggested in the Standard will increase the safety and durability of buildings in corrosive environments for a very small increase in the overall cost. This again leads to the debate about what constitutes a corrosive environment, and whether the Standard should be more conservative.

The revised Standard has been incorporated into the Building Code of Australia and is mandatory for many provisions in the Code. The Australian Building Codes Board anticipates AS3700 - 1998 will become mandatory for the Housing Provisions in January 2000.

Thus, opportunities exist for the stainless industry to be proactive in its approach to such issues, as well as to investigate the use of stainless in other building applications, where durability and strength are principal concerns.

This article featured in Australian Stainless magazine - Issue 13, May 1999.


Posted 17 May 1999

When the United States Navy required 35 lightweight transportable recompression chambers in the late 1980s, Cowan Manufacturing took up the challenge of developing the units.

Cowan Manufacturing developed a prototype out of a virtually unknown material. It was duplex 2205 (UNS 31803) stainless steel.

No other manufacturer in the world was producing chambers out of 2205 and, after six years of negotiations, Cowan was sourced as the sole supplier of the chambers.

Cowan chose 2205 for its high strength, light weight and corrosion resistant properties. This enabled them to meet the Navy's requirements without the weight and corrosion problems of other materials.

Traditionally, recompression chambers have been made out of carbon steel and required high maintenance because of the severe marine environment in which they are used (on ships at sea). Chamber walls had to be thick to combat the effects of corrosion and so were very heavy.

The strength and corrosion resistance of 2205 over other materials enabled the chamber shell thickness to be reduced to 3mm. The thinner chamber walls effectively halved the weight of the units and corrosion resistance lengthened their service life.

However, Cowan faced some difficulties with the material because it was new on the market at the time. Staff had to be specially trained in welding techniques for the 2205 which had to be approved by Navy certification teams. (2205 is now a common material that is used for many industrial applications.)

The 2205 material was supplied by Sandvik Australia. The 3mm x 2000mm wide coil material was sized on its cut to length line and plasma arc cut the conical sections and the end cap discs which were then formed by Dome Engineering.

The strict quality requirements specified by the US Navy resulted in all material being ultrasonically examined and charpy tested before processing.

The chambers were produced at the Cowan Manufacturing facility at Warners Bay in New South Wales. Cowan has since become a specialist
in its field, supplying recompression chambers to 12 countries including the United States and Australia.

This article featured in Australian Stainless magazine - Issue 13, May 1999.


Posted 28 February 2000

When the Gold Coast City Council was seeking a stable and visually stunning medium for use on their Kirra Point board walk project, they looked no further than stainless steel!

Geoff Clemence, Design Coordinator, said Council engineers chose stainless steel for the upright posts and moveable hand rail system for safety, corrosion resistance and aesthetic reasons.

"Stainless is far superior to wooden handrails in terms of safety and lasting life and will require far less maintenance," Mr Clemence said.

"From an aesthetic point of view, the stainless steel fits in beautifully with both the concrete pavement and the timber board walk that we will be installing in the near future," Mr Clemence said.

"Once the board walk is built, there will be a vertical drop to the beach below - an important safety issue met by using stainless steel handrailing.

"We had to choose what the best solution would be to the issue of safety that the steep drop off on the side of the walkway would cause," Mr Clemence said.

"Stainless steel was the safest option."

The board walk project is being undertaken in two stages, the first of which involved constructing a cement walkway and handrails along the Kirra Point foreshore.

The second stage will see the construction of a timber board walk out over the foreshore onto the beach.

ASSDA Sustaining Members Tom Stoddart Pty Ltd supplied 186 custom made upright posts and supplied and installed 326 metres of stainless steel tubular handrails.

Both were made from 316 grade stainless steel with a number 4 finish.

The upright posts were passivated in nitric acid after manufacture to ensure a clean surface and promote corrosion resistance.

During the installation, the welds in the posts were fully grounded and polished on site to stop sand and salt deposit build-up.

The hand railing is made up of 6 metre segments of tubular stainless steel welded on site.

Expansion joints are included every 7.2 metres.

The expansion joint allows for thermal movement and the inclusion of additional railings when a timber board walk is built in 2001.

The Gold Coast City Council engineers acknowledged the assistance provided by the Australian Stainless Steel Development Association in highlighting the possibilities and advantages of stainless applications, in meetings leading up to specification in the project.

This article featured in Australian Stainless magazine - Issue 15, February 2000.


Posted 28 February 2002

The Tasmanian Government has embarked on a series of bridge renewal projects, using stainless steel reinforced pre-cast concrete to replace old timber structures.

The Barnes Creek bridge is the first of three to be rebuilt on Brunie Island, south of Hobart. It utilised 7.5 tonnes of grade 316 and duplex 2205 stainless reinforcing bar in a size range of 12 to 25mm supplied by ASSDA member Arminox Australia Pty Ltd.

The Tasmanian Department of Infrastructure, Energy and Resources specified stainless steel for the reinforcing to save on ongoing maintenance costs. The location of the bridge presents construction and maintenance challenges, with the site only accessible by ferry.

The grade was selected to meet the demands of an aggressive marine environment. The bridge is subject to salt-laden winds and salt water covers the foundations at high tide. The 6.5m bridge, which connects local rural and residential areas, has a service life expectancy in excess of 100 years.

SORELL CAUSEWAY
Another of the Department's major projects is the construction of a new 490m bridge connecting the Tasmanian east coast to the Tasman Peninsula. The new Sorell Causeway has been designed to cater for heavy vehicles, a high volume of local traffic and tourists travelling from Hobart to Port Arthur. A small quantity of only 6.5 tonnes of stainless steel 316 and duplex 2205 reinforcing is being used in the critical area of the pile cappings.

This article featured in Australian Stainless magazine - Issue 20, February 2002.


Posted 28 February 2002

The superior strength of stainless steel has long made it the material of choice for prison toilet facilities. Innovative styling has now opened up a new market in public restrooms. Increasingly, venues are turning to stainless steel to make their facilities safer and reduce costs in the long term.

Vandalism in public facilities is a widespread occurrence, with some pub and club owners forced to replace a toilet every few weeks. While the initial outlay may be higher for stainless fittings, the cost of replacing and installing a ceramic pan can be recouped after just one instance of vandalism. Unbreakable stainless steel also eliminates the risk of injury from sharp ceramic shards and the inconvenience of effluent overflow.

Stylish designs mean that aesthetics aren't sacrificed for practicality. Martin O’Brien, General Manager of the recently refurbished QA Hotel in Brisbane’s Teneriffe, says stainless steel was the logical choice because it’s "tough as teeth, durable and looks good. Stainless steel was the best way to go - its clean lines never go out of date." As part of a total makeover, the QA replaced ceramic tiles and fittings with stainless steel. O’Brien says vandalism in pubs is a big issue, with "punters" taking out their frustrations in the bathrooms and causing a lot of damage to conventional fittings.

ELEGANT AND FUNCTIONAL
Metal, timber and black are the predominant themes in the $3 million refurbishment of the 120-year-old Regatta Hotel, overlooking the Brisbane River. Conceived by owner-developer Steve Hammond, the renovation juxtaposes high tech and rustic, with gleaming metal and glass surfaces set against timber frames and sandblasted brick walls. The metallic theme continues outside with stainless steel topped café tables on the pavement and verandahs, and aluminium louvres replacing traditional lattice.

Stainless steel is integral to the washroom design, combining clean, minimalist lines with durability, vandal-resistance and minimum maintenance. Push pad controls replace vulnerable taps, while moulded stainless steel pans with in-wall slimline cisterns and push pad flush eliminate other targets for vandals. Stainless steel is used for mirrors, air-towels, soap and toilet paper dispensers.

Stainless steel fabricator Stoddart, who drew on the resources of ASSDA to develop a commercial product range, says their pans are often specified as part of a suite to fit in with a high-tech, architectural look. This project used Stoddart's standard shrouded toilet made from satin finished, 316 stainless to withstand heavy duty cleaning products. A pin inside the bowl prevents objects like wine glasses being flushed into the plumbing. The flat plate design of the rim flush makes the toilet contraband-proof and the unit has the advantage of being able to be fixed onto a wall from the inside.

Stainless steel features heavily elsewhere in the bar frames and counters and in a microbrewery. Three 2 000 litre stainless steel tanks with decorative copper cladding have been incorporated into the design of the downstairs bar. The beer is piped to fermentation tanks in the upstairs bar, which form a backdrop to the dancefloor. Apart from providing a theming enhancement to a predominantly beer pub, the installation of a microbrewery was a commercial decision in response to a growing demand for boutique and specialty beers, says project manager Rob Forbes.

BEACHFRONTS AND PARKS
Local authorities present another significant market for stainless steel amenities. Gold Coast City Council, which for some years has had a policy of replacing vandalised ceramic toilets with stainless steel ones, is now installing stainless steel pans in all new public convenience blocks. To improve safety, the Council is also considering installing stainless steel woven security mesh near the entrance of public toilets. The one-way screen allows people to see if is there is a threat outside the building before exiting.

STYLISH STAINLESS SHOWERS
In conjunction with Stoddart, Gold Coast City Council is developing a prototype stainless steel shower to eliminate the corrosion problems of beachside installation. Ian Munro, Supervisor in the Council’s Building & Maintenance section, says the project has attracted interest from other councils on the coast. Seven showers are currently being tested. ASSDA member Stoddart has also manufactured stainless steel street furniture for Casuarina Beach on the Tweed Coast in northern NSW including beach-themed showers in 316 stainless. These are designed to be vandal and weather resistant and feature automatic water cut-off to prevent wastage.

Image on left: Casuarina Beach 316 stainless surfboard shower. Design by Hutton-Harris. Fabrication by Stoddart.

This article featured in Australian Stainless magazine - Issue 20, February 2002.


Posted 1 September 2002

Pedestrians using Brisbane’s scenic RiverWalk when it opens next March will be strolling across 150 tonnes of stainless steel reinforcing, embedded in 287 concrete pontoons linked to form an 875 metre long walkway from the CBD along the river to New Farm Park.

Although the 5.4 metre wide walkway will feel like a single solid structure, it is actually made up of a series of 13.5 tonne concrete blocks, half of their bulk floating below the water level.

Stainless steel balustrades will preserve open views across to Southbank and back to the CBD while ensuring public safety. These combine subtly curved 600 grit electropolished handrails which give a wave effect and 320 grit polished end-posts and staunchions with an art deco feel.

An overall Ra of 0.5 mm was specified not just for the aesthetics but to provide maximum corrosion resistance for grade 316 stainless in a marine environment and to minimise tea-staining.

Stainless steel wire strung horizontally between the posts will provide a strong safety barrier while fading to invisibility from just a few metres away. Customised tamper-proof electropolished turnbuckles developed by ASSDA member Ronstan International Pty Ltd and the posts inward-curving profile will ensure that RiverWalk meets stringent safety standards.

Night-time illumination will come from Y-shaped light poles placed at 30 metre intervals and spot lighting will highlight decorative elements such as mosaics.

Each section of the balustrade runs the length of an individual pontoon. Sections are joined with a tapered stainless steel sleeve to absorb the small amount of movement from wave action, expected be around 20mm.

AN INNOVATIVE BASE FOR A SCENIC WALKWAY
Assembly of the concrete pontoons involves advanced construction methods modelled on the latest overseas developments and a similar, but much smaller, floating walkway which was successfully built on Melbourne’s Yarra River.

To obtain the necessary strength and buoyancy, high strength 50mPa concrete is reinforced with grade 316 stainless steel. The 10mm and 12mm diameter rebar is fashioned into a cage around a polystyrene core which takes up 85% of the pontoon’s volume. The corrosion-resistant properties of stainless steel reinforcing enable the pontoon to be built with narrower walls than would be the case with conventional reinforcing creating savings in the amount of concrete required.

With stainless steel reinforcing an impressive lifespan is assured, making it the best long-term option in building assets where longevity is desired. The design life of this structure is 100 years.

Funded by the Brisbane City Council (BCC) and developed by a BCC and consultant design team led by project architect Jan Jensen, RiverWalk is one of the city’s most ambitious and forward looking projects. It uses techniques which are new to Australia and draws on the expertise of many construction professionals including stainless steel materials experts, suppliers and fabricators.

ASSDA’s role in the project included detailed specification advice on all aspects of the stainless steel work and provision of detailed answers to technical issues in design and prototyping.

Construction contractor Smithbridge Australia Pty Ltd heads the project team which also includes a number of ASSDA members, including Pryde Fabrication, Arminox Australia Pty Ltd and Stoddart Metal Fabricators.

This article featured in Australian Stainless magazine - Issue 22, September 2002.


Posted 1 December 2002

Advanced engineering solutions are required to handle conditions found on offshore drilling and processing platforms. The saltwater environment is highly corrosive, the flare presents extremes of temperature and the force of winds and currents is constant. The most durable and reliable materials need to be employed, which is why stainless steel plays and important part.

An impressive project making use of stainless' strength and corrosion-resistance is the Bayu Undan Gas Project in the Timor Sea, 5OOkm north of Darwin (pictured). Here, stainless steel is used to line the 18" pipelines between the processing platform and the wellhead platform 8km distant and in thousands of metres of pipes throughout the installation.

SPECIALIST BRIDGE BEARINGS
Stainless steel and high nickel alloy bearings support various bridges, including a 225m long bridge from the drilling platform to the flare. The bearings have been designed by specialist engineering and manufacturing firm Ludowici Ltd of Sydney, working closely with the project consultants TIGA JV of Perth. The bearing shown above is mirror polished to slide ±600mm while supporting a 900 tonne load, with operating temperatures up to 220°C due to the flare. In addition to continuous wave action, the bearing is designed to withstand 160 tonnes of transverse load due to gale force winds during tropical cyclones, as well as "bumps" during installation.

Bayu Undan is a project of Phillips Petroleum Company Australia Pty Ltd. Gas and liquid hydrocarbon reserves were discovered in 1995. It is estimated that the 25km by 15km field has a 25 year life and reserves of 350-400 million barrels of hydrocarbon liquids and 3.4 trillion cubic feet of gas. Work on the site is proceeding with full commercial production due by 2004. The first phase of the development, representing a US$1.4 billion investment, involves production and processing of wet gas. A second phase is planned to harvest the field's gas reserves.

Ludowici became involved in Bayu Undan in mid 2001, when it was chosen to design, manufacture, test and supply eight highly complex stainless steel pot-type bearings.

The design team drew on technical expertise of the Australian Stainless Steel Development Association and the Nickel Development Institute to produce a suitable design.

BUILT TO WITHSTAND WIND, WAVES AND WATER
The brief presented some unique challenges including massive steel superstructures requiring high-strength low-friction supports, to be left maintenance-free in a remote, aggressive tropical marine environment. Some were required to have uplift capacity, all were to be resistant to salt build-up, and all were required to be virtually maintenance free for a 25 year life. Whilst the majority of the bearing components ('pot' cylinders and pistons) were made from 316 and 316L stainless steel, the large-movement slide plates were made from grade 2205 duplex stainless steel, with a facing of polished Inconel 625, fully TIG welded around its perimeter. Thermal coefficients of expansion of mating parts were matched. Assembled bearings were tested in overload and friction, both at ambient temperature at 140°C.

The bearings were fabricated at the firm's Castle Hill, Sydney factory and transported to Batam, Indonesia where they were incorporated into the structure for the final trip to site.

The bearings measure up to 2m long and weigh up to 3 tonne each with attachments plates. They were also designed to withstand severe impact during installation.

The various bridges, platforms and piping are currently bring assembled.

For more information on Bayu Undan, visit www.offshore-technology.com/projects/bayu-undan

This article featured in Australian Stainless magazine - Issue 23, December 2002.

A Style Statement in Stainless


Posted 1 December 2002

The transformation of Sydney's Walsh Bay from derelict wharves and sheds into a prestigious residential complex, complete with cultural, retail and commercial facilities, provides a stage for Australian innovation in design and technology, including some of the finest examples of stainless steel structural and architectural applications.

Located amid Sydney's landmarks -the Opera House, Circular Quay, The Rocks and Sydney Harbour Bridge -the Walsh Bay Precinct is said to be "the most significant urban renewal of heritage Sydney to be undertaken for many years."

According to developers Walsh Bay Partnership (WBP), a joint venture project between Mirvac and Transfield, "the redevelopment captures an exceptional balance between Walsh Bay's rich heritage, sympathetic contemporary design, and the vision to revitalise Walsh Bay as Australia's finest new residential address."

The development features 350 luxury apartments, 140 of them located on Pier 6f7, one of the five "finger wharves" constructed between 1906 and 1922 to serve Sydney's expanding commercial shipping activity. But the area's history goes back much further: Walsh Bay was one of Sydney's first industrial ports, dating back to 1820. Like many other city ports around the world, Walsh Bay ceased operations in the '70s and by the late '90s much of the area was unused and neglected.


New Technology Preserves Authentic Feel
WBP was formed in '97 to undertake restoration, with an emphasis on conservation strategies such as salvaging the old hardwood timbers and historical artefacts. Over 80% of the original buildings are being retained and the style of new construction is required to evoke and interpret Walsh Bay's rich heritage. Preserving its historic appeal, unique operable louvres which mimic the original timber planks face the 200m long refurbished pier. These are made from aluminium and supported by grade 316 stainless steel brackets. The louvres pivot on stainless steel supports, allowing them to withstand winds up to 130krnlh. As a safety measure, they close automatically if the weather worsens. They were designed by Architectural Glass Projects Pty Ltd, a Sydney firm which specialises in building components such as glass facades, operable louvres, balustrading and specialised glazing.

 

Stainless to Resist Sea Spray
To take best advantage of its Sydney Harbour location, a marina with private boat moorings accessible from ground-level apartments runs along both sides of the pier and features     stainless steel steps, gates and balustrades.

Starting with the right materials and selecting the most appropriate surface finish are key factors for ensuring the quality and life-cycle of the finished project, particularly in harsh marine environments. A surface roughness (Ra) under O.SJ.Jm using 320 grit abrasives was specified for the stainless steel used in this project. Mechanical grinding was followed by electropolishing, a chemical process which smooths and levels the surface, to produce the best protection against tea staining and contamination.

Surface treatments were carried out by two ASSDA members, MME Surface Finishing and Metaglo Pty Ltd. A large proportion of the stainless steel material used was imported large extruded T and 'L' sections up to 150mm deep. MME, which has the capacity to process elements up to 6.5m long by either mechanical means or electropolishing, modified machines and developed new techniques to produce a consistent O.SJ.Jm finish throughout. Components were returned to MME after fabrication for immersion pickling and electropolishing.

An Asset for Sydney
The revitalised Walsh Bay precinct is set to become an attraction for residents and visitors when it opens next year. As well as offices and apartments, the development includes a new cultural centre, an 850 seat theatre, parks, restored bridges and walkways. A promenade will link Walsh Bay to The Rocks and Circular Quay, opening up the foreshore to the public for the first time in over a century.

This article featured in Australian Stainless magazine - Issue 23, December 2002.


Posted 1 March 2003

Grade 316 stainless steel offers superior corrosion resistance and has become the norm for architectural applications within 5km of the coastline. Another natural use for grade 316 stainless is in boating and marine sports gear, which has to withstand the corrosive effects of salt water.

Deck fittings and equipment made in 316 stainless are stronger and more durable than most alternatives. Their lifespan is further enhanced when kept clear of salt encrustations, grease and dirt. This is facilitated by a very smooth surface which doesn't present miniscule pits and crevices where corrosion can begin.

An example of grade 316 being used to good effect is the Cannon Rod Holder by ASSDA member Emro Products. For the benefit of the non-fisherperson, a rod holder is mounted onto the side or deck of the boat to hold the fishing rod and free up both hands for other tasks.

Using several rod holders when trolling allows more lures to be placed and the area covered is increased if the holders are angled at 90 degrees to the sides of the vessel.

The Cannon is made from highly polished grade 316 stainless steel, rigorously tested to ensure a durable and reliable product. It is fully adjustable so that the rod can be positioned as desired. Being detachable it can be easily cleaned and is less vulnerable to theft.

The D locking mechanism in the base of the shaft ensures that it attaches securely and cannot be accidentally released, losing both valuable fishing equipment and the catch.

The rod holder is manufactured in two lengths, 145mm long with rubber buffers on either end and 300mm long with a pin in the end to suit a gimbal.

This article featured in Australian Stainless magazine - Issue 24, March 2003.


Posted 1 March 2003

To symbolise the wetlands landscape of the Nundah area in Brisbane’s north, sculptor Daniel Della Bosca sought out materials which best convey the fluidity and reflectivity of water and the reedy texture of waterside vegetation.

His choice was 316 stainless steel, finished with specialised surface treatments, combined with translucent blue glass and earthed in basalt.

“Dancing Wall” was commissioned by Brisbane City Council (BCC) as part of its program of Suburban Centre Improvement Projects (SCIPs) which aim to improve economic vitality, focus on community life and enrich local activity. The Nundah SCIP is one of the larger projects in the scheme with a budget of $2.5m.

The artwork is a sculptural balustrade set on the hilltop at the corner of Buckland Street and Sandgate Road. Its design symbolises the local environment which was once rich in waterholes and is now the focus of BCC and Wildlife Preservation Society rehabilitation initiatives.

According to Della Bosca, the piece is not just about the past: the materials and design provide an inspirational link to the future.

The client has expressed satisfaction with the completed project, with Deputy Mayor Councillor Quinn commenting that it fulfills the Council’s objectives of “good design and creative activity to build a prosperous city.”

FABRICATION

“Dancing Wall” was fabricated by Della Bosca in grade 316 stainless plate, flat bar and rod supplied by ASSDA member Austral Wright Metals. It houses five panels of slumped and toughened ‘azurelite’ glass, made by artist Shar Moorman, internally illuminated by concealed LED lighting.

Most of the structure was fabricated from rolled stock to bring an organic quality to the design. The intricate forming was carried out by local firm BJR Metal Rolling & Pressing who specialise in rolling compound curves.

SURFACE FINISH

Integral to the design are the surface treatments which suggest reed and water textures. ASSDA member Australian Industrial Abrasives helped to investigate the products, appropriate tooling and techniques to achieve the desired effects. The finishing on larger areas was completed with a Dynacushion on a variable speed sander polisher, using abrasive belts in a range from P80 to P150 Zirconia/Alox and finishing with 3M Blue Scotchbrite. The tighter, more intricate areas were finished using a Dynafile and various contact arms and the same range of abrasive belts.

An easily achievable, cost-effective maintenance schedule using an activated surfactant cleaner quarterly and a passivation gel as required has been implemented by Brisbane City Council.

The cleaning agent removes oil, grease and dirt, and also removes surface free iron which may cause discolouration or more serious corrosion.

This step is followed by a passivation gel which chemically generates the chrome oxide passive film on the surface to enhance corrosion resistance for stainless steel installed in high corrosion environments.

ARTISTIC POSSIBILITIES

Della Bosca says the qualities of stainless steel can best be conveyed by allowing the material to interact with light. “As fabricators well know it is easy to ‘muddy’ the surface of stainless, but if care is taken and correct procedures followed, the metal can give opportunities to a surface finisher.

“I work with the stainless to allow it to speak of more than itself. This is much more important to me than trying to force a finish.”

This article featured in Australian Stainless Issue 24 - March 2003.


Posted 1 July 2003

Architect Jan Jensen was a consultant to Brisbane City Council on the design of the Brisbane Riverwalk, currently under construction. The walk will take pedestrians from the CBD to the inner suburb of New Farm along the river.

At this proximity to Moreton Bay, the water is brackish and the air salt-laden - it is destructive to most construction materials. Corrosion-resistant stainless steel was chosen for this landmark project to deliver the 100 year service life required by the asset owner.

The structure consists of floating pontoons, reinforced with 316 stainless steel deformed bar. There are stainless steel balustrades and light poles and a suite of stainless street furniture.

Jensen describes the process of specifying the correct finish, including gaining a theoretical understanding and producing prototypes:

The Starting Point
As a key parameter of design responsibility 'value for money' the decision to use stainless steel was an easy one. Our rationale was: "It doesn't corrode and our work is in salt-affected air; it lasts forever; it is low maintenance; it will save us money and keep on looking good."

We needed a specification to let contracts for the manufacture of street and riverscape elements. Writing a specification required describing and reproducing the manufacturing process exactly to get reliable, predictable, consistent and economic results.

Our research took us to ASSDA's timely seminar on the fifty most frequently asked questions about stainless steel, where we were able to ask about tea-staining and how to avoid it.

Then we talked to manufacturers. The answers to our questions about surface roughness and the finishes available made us realise there were variations within the industry and we needed to define our requirements with scientific precision. Specifically, we needed to know the surface roughness (Ra) in microns (µm), as the labels 2B, No. 4 and so on refer to the method used to achieve the finish and comprise an Ra range.

Building Prototypes
We concluded that to write our specification we needed to build the product first to set it within the theory and the 'standard range of common industry manufacturing practice'. We commissioned prototypes of a balustrade and a light pole then the furniture suite for the Riverwalk: seats, bollards, bins, lights, sign posts and drinking fountain.

Forge Brothers Engineering produced the prototypes. It drew on the expertise of ASSDA and its members University of Queensland Materials Performance, 3M Australia, Heat & Control, Condamine Wellscreens, Ronstan International as well as AbrasiveFlex and Dana Ridge.

We soon realised that:

> The common system of finish grades is not a measure of surface roughness, eg the Ra of No. 4 finish products measures anywhere from 0.45 to 0.8µm depending on product form and supplier. Typical Ra for sheet is 0.3 to 0.4µm while it is not unusual for other products such as flat bar to be rougher. Thick plate, thin plate (sheet), tube, flat bar and hollow bar are manufactured by different processes which produce different finishes. The surface finish changes in hot rolled plate and gets smoother as the plate reduces in thickness.

> Ra meters were not commonly used in the industry although their use is growing.

> All abrasives aren't the same. Wear and tear and pressure make a difference. We tested non-woven abrasive belts, Trizact belts, air wheels and silicon carbide.

> The electro-polishing industry uses a variety of chemical baths and voltages.

Towards a Specification
In arriving at our specification we learned:

> Best practice calls for a finish below 0.5µm combined with electro-polishing to eliminate sulphides and increase the chromium content of the exposed surface.

> Wet blasting at low air pressure levels with a water and abrasive bead mix provides a consistent surface finish and economically removes surface variations ready for electro-polishing. This avoids the unexpected rise in roughness which can occur when electro-polishing removes microscopic peaks, previously flattened by mechanical polishing, to uncover underlying pits.

The proof that our specification works can be seen on the Brisbane River. After twelve months in a salt air environment our prototypes are still looking clean and new.

Words by Jan Jensen.

This article featured in Australian Stainless magazine - Issue 25, July 2003.


Posted 30 November 2003

Coastal areas are popular sites for recreational fun and fantastic fishing. However, the City of Albany in Western Australia had one major problem to deal with - fish waste in the nearby waterways

Local fishermen were cleaning and filleting fish and disposing of the waste overboard. This waste not only stagnated in the water for days, but also attracted seals and stingrays that can become aggressive when feeding.

Faced with a situation of replacing what was a kitchen sink on rusty legs in the water, the Council turned to local ASSDA member, Austenitic Steel Products, to design and fabricate an innovative new stainless steel fish cleaning station for the Emu Point Boat Ramp.

The circular fish cleaning station is believed to be the first and only one of its design currently available in Australia and measures 1400mm in diameter and 1100mm high.

Produced in 316 stainless, the compact design allows six operators at a time and provides a safe environment with no corners or sharp edges.

All plumbing is internal with access only through a hatch on the face of the cone and fitted security locks. Waste water falls to the centre of the table and flows through a circular screen into a collection hopper before entering a two inch waste pipe concealed in the centre.

Initially, the station requires manual removal of offal, but when funding and municipal sewerage is available, the table can be modified to incorporate an automatic processor to pulverise offal into disposable liquid waste.

Albany City's $13,000 station project has generated interest from other Councils and looks set to appear in local boat launching areas, coastal caravan parks and seaside fishing locations throughout Australia.

This article featured in Australian Stainless magazine - Issue 26, November 2003.



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