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Posted 25th September 2009

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Posted 1 March 1998

Stainless steels are now cheaper than ever, but there is still room to minimise costs (see Table 1), which will improve the bottom line for individual companies, projects and the industry as a whole.

Flat productsAustralia is a relatively 'small fish' in the global stainless industry and, without the benefit of local stainless steel production, loses some flexibility on product availability. Unless you're a very large consumer of stainless steel to a single specification or Standard, ordering to common specifications will reduce costs and increase availability of products.

Flat Products - Table 1Suppliers are likely to have products to common specifications. Ordering them reduces the need for slow moving stock, increases stock turns, raises the size of single orders, and can substantially reduce costs. A similar mechanism works for mill or mill indent orders.

Flat products

Until recently, stainless steel flat products manufactured to Australian Standard 1449 were the most widely available in Australia. However, since the closure of BHP Stainless in 1997, products manufactured to this Standard are no longer commonly produced. More common international specifications will need to be recognised in Australia if economies are to be achieved (see Table 2).

Fortunately, the transition may not be difficult, because AS1449 was closely aligned with the ASTM Standards from the USA, which are also similar to the Japanese JIS Standards. Steels identical to AS1449 in nomenclature, chemical composition, mechanical properties and surface finish are readily available internationally.

Today the most commonly available stainless flat product in Australia is manufactured abroad to ASTM A2401A240M Standard specification for heat resisting chromium and chromium-nickel stainless steel plate, sheet and strip for pressure vessels, which nominates ASTM A4801A480M for additional general requirements of the steel ('M' designates the metric version, which is more appropriate in Australia).

European specifications are also emerging and EN 10088 Stainless steels has the potential to become a common specification in the Australian market. EN 10088 makes use of the established German names and numbers for stainless steel grades, Many grades in EN 10088 have close equivalents in the ASTM based Standards, but the nomenclature for grades and finishes is very different and replacements should be examined carefully. For example, in AS1449, ASTM A240M and JIS G4305, grade 304 (the most common stainless) has a minimum of European specifications are also emerging and EN 10088 Stainless steels has the potential to become a common specification in the Australian market. EN 10088 makes use of the established German names and numbers for stainless steel grades. Many grades in EN 10088 have close equivalents in the ASTM based Standards, but the nomenclature for grades and finishes is very different and replacements should be examined carefully. For example, in AS1449, ASTM A240M and JIS G4305, grade 304 (the most common stainless) has a minimum of Ordering at standard width and thickness is the best way to keep steel costs down. Each mill has equipment capable of a certain maximum width and running narrower steel is less productive.

The standard width varies from mill to mill (see Table 3), with most European mills manufacturing at 1,200mm or 1,250mm wide, with a few capable of 1,500mm and, for some thicker coil products, 2,000mm. Mills in Asia tend to standardise on the imperial widths 3', 4' and 5' (914mm, 1,219mm, 1,524mm).

Conclusions

An understanding of commonly used specifications can lead to more efficient and cheaper practices. If questions arise, your supplier or fabricator may have information on alternative Standards that are more commonly available and more suited to your requirements.

Flat Products - Table 2

 

This article featured in Australian Stainless Issue 11 - March 1998. More current information can be found in ASSDA's Australian Stainless Reference Manual.


Posted 1 March 1998

Stainless steel forms a significant part of a beef abattoir, including the conveyors, fixed and elevated platforms, sterilisers, chutes, hand wash basins and, of late, water supply and wastewater piping. The stainless component may now expand even further in new abattoirs with the recent development of cast stainless steel skids and forged hooks for use on dressing conveyors.

AbattoirDressing conveyors in beef abattoirs traditionally use rollers rather than a skid system or, in some cases, extruded aluminium skids and hooks are used. Both of these systems have limited service lives due to the weight of the beasts. They also result in downtime when cleaning and, in the case of rollers, lubrication is required. Hygiene is critical throughout the trimming process, as the carcass' meat is exposed to the environment.

G & B Stainless (Crestmead, Old) and Meateng (Melbourne, Vic) recognised the need to develop a dressing conveyor system which would allow a rapid turnaround of hooks while assuring a high level of hygiene.

Using stainless steel would provide sufficient strength to hold heavy carcasses (weighing up to 1,000kg), while allowing the skids and hooks to simply pass through a washbox for sterilisation on their return to the starting point of the conveyor.

The project has evolved over six months from a prototype fabricated skid, which did not provide enough strength, to the existing cast skid and forged hook. The cast skid also incorporates a high density polyethylene insert, which is the only component to experience wear during service. This insert can be replaced at low cost when required.

The skids are cast by Austcast Stainless (Northgate, Old) using a vertical joint automoulding sand casting system. Grade AS2074 H5A (equivalent to AISI 304) stainless is used and full traceability exists for the castings, The stainless hooks are forged by John Ure (Wacol, Qld). Production costs are comparable with extruded aluminium skids, but the low rate of replacement makes the lifecycle costs very attractive.

Over 1,000 stainless steel skids and hooks have been in service at Stockyard (Grantham, Qld) for six months and, according to site engineer, Roger Tocknell, they have been performing excellently.

The new skids are not interchangeable with existing mild steel rollers, but G & B Stainless' Director, John Van Koeverden, said the company's next goal is to develop stainless rollers which can be used on existing conveyors.

This article featured in Australian Stainless Issue 11 - March 1998.

Posted 1 March 1998

Kuala Lumpur's new international airport terminal will open within a month and travellers will be sheltered by a A$17 million stainless steel roof which has largely been developed by Australian expertise and innovation.

KL airportThe roof profile of the contact piers and air bridges (60,000m2 total area) had to satisfy a number of criteria, including rainwater runoff, resistance to wind uplift, and a smooth, painted appearance. The roof area comprises a composite system with an outer metal membrane of fully-welded stainless steel. Further complicating the design, the architect (MJAC) wanted to avoid valley gutters on the roof's curves.

Around 280 tonnes of 0.4mm grade 316 stainless were used for the roof and unique, tapered sheet, roll forming technology was developed to accommodate curvatures in the roof. While rollforming is normally used on parallel edge products, Chadwick Technology (Forestville, NSW) and Horton Engineering (New Zealand) developed a rollformer which was capable of rolling roof sheet in excess of 20 metres long, with the edges tapering to a pre-determined dimension. All of the taper, shear and rollforming equipment was computer controlled to obtain correct dimensions.

Similarly, a fully automated welding system was designed to weld at 5 metres/minute (resulting in a total of 125km of welding), with the generated heat being water cooled. Fixing clips, which were welded within the seam roof, had to allow for thermal movement of up to 20mm. To provide the unwelded surface appearance, a rib cap was designed to conceal all the welds, fixings and unpainted sections.

Bill Mansell, Chadwick's Engineering Director, said MJAC specified stainless steel to provide the client with a lifetime investment in maintenance free roofing. The stainless steel sheet, which was coil coated with a dark green fluorocarbon PVf2, was supplied by Avesta Sheffield (Castle Hill, NSW) and special end fascia and architectural trims were fabricated by the Townsend Group (Mortdale, NSW).

The airport is opening in February/March this year and it will be fully operational for the Commonwealth Games in September 1998. The roof, which is a finalist in the Gold Circle Award for Innovative Roofing from the USA's National Roofing Contractors Association, is certain to give international visitors to Kuala Lumpur a strong, visual impression of Australia's design and fabrication capabilities.

This article featured in Australian Stainless Issue 11 - March 1998.


Posted 1 March 1998

A pilot magnesium processing plant is currently under production in Gladstone, using unique technology developed in Australia and incorporating a significant stainless steel component.

MagnesiumThe Australian Magnesium (AM) process (now owned by the Australian Magnesium Corporation - Brisbane, Qld) was jointly developed by Queensland Metals Corporation (QMC - Brisbane, Qld) and CSIRO to process the type of magnesite ore discovered by QMC near Rockhampton into highly pure magnesium metal.

The process incorporates a number of patented features which will be demonstrated and refined at the pilot plant in Gladstone on its completion in mid-1998. The AM process involves the use of a variety of harsh acids, requiring the specification of stainless steel grades such as 2205, 2507, 2RK65, 904L, 316L and 316H to withstand a range of corrosion environments.

Approximately $1.5 million has been spent on stainless steel components for the magnesium pilot plant, including stainless piping, pumps, compressors, tanks and shell and tube heat exchangers.

Eight fabricators supplied the components, including D & R Stainless (Salisbury, Qld), who fabricated seven stainless steel vessels using material ranging from 3mm to 13mm in thickness.

If the project progresses to full production of 90,000 tonnes of  magnesium per year, the plant will be 60 times larger than the pilot plant and the cost will expand to around $800 million. Construction is currently planned to commence towards the end of 1999 and commercial operations should begin at the end of 2002.

Magnesium is commonly used for automotive parts, such as instrument support panels, seat frames, transmission casings and rocker covers. Other common uses for magnesium are in laptop computer frames, chainsaw bodies and sporting equipment such as tennis racquets.

This article featured in Australian Stainless Issue 11, March 1998.


Posted 1 March 1998

Sydney's recently redeveloped Chifley Square now pays tribute to its namesake in a dramatic, yet personable, manner - an 8m tall stainless steel sculpture of Ben Chifley towers over the square, forming part of City of Sydney's capital works program in the lead up to the Sydney 2000 Olympics.

Chifley_3Sydney artist Simeon Nelson designed 'Ben Chifley' and a glass and stainless steel wall on the site while working as part of the multi-disciplinary design team involved in the site's $3 million redevelopment. Hassell architects (Sydney) were given open guidelines for the design of the site, but two of the objectives were to see Chifley appropriate recognised and to provide a windbreak on the Hunter Street side of the square.

Nelson specified 5 tonnes of 20mm grade 316 stainless plate for two cut-out images of the former war-time treasurer and the post-war Labor prime minister. The plates are positioned in parallel and bolted to a stainless frame, allowing 1mm tolerances.

Nelson designed the sculpture in stainless steel because of its long-term durability. He also felt the material was appropriate because it is often used as an industrial product and Chifley kick-started industrial growth after the war.

The sculpture was fabricated by CBD Prestige Metal Works (Sydney) from material supplied by Sandvik Australia (Smithfield, NSW). After shotblasting by IMP (Sydney), the final surface finishing and passivating was carried out by BHM Stainless Technology Group (Keon Park, Vic) using a specialised process developed by the company for unusual projects of this nature.

Chifley_wallSimilarly impressive is the 'Lightwall, Crucimatrilux' (also fabricated by CBD), which incorporates panes of transparent glass bolted together on nine stainless frames made of 74mm x 20mm bar with a mill finish. Because of the fine tolerances required, dowel and glue were used instead of welds to hold the frames together.

The 10.8m long and 3.2m tall wall serves a structural function as an extension of the back wall of the cafe and also acts as a wind shelter. visually, it provides a contrast with cafe's wall, which is made from white coated glass.

The redevelopment of the site, which is semi-circular in shape and divided in half by Philip Street, was aimed at unifying the two spaces to reflect the original intent of the site's 1937 design. Together, the Lightwall and Chifley sculpture form part of an impressive, contemporary response to historic town planning.

This article featured in Australian Stainless Issue 11, March 1998.


Posted 1 June 2002

Hastings Caves, one of Tasmania’s major tourist attractions situated a scenic two hours’ drive south of Hobart, has received a major upgrade.

According to the Site Co-ordinator Keith Vanderstaay, the caves "have been reinvented with the completion of a state of the art, computer-controlled lighting system which will change the way everybody will see the cave."

New stainless steel handrails allow visitors to navigate the cave in safety, and are designed to last for generations, minimising the need for maintenance in the caves' sensitive environment.

Tasmania’s Parks and Wildlife Service, as part of a safety review of structures used by the public, identifed the 1930s galvanised pipe handrails as substandard to the new AS2156.2 Walking Track: Infrastructure Design and decided to replace them.

Another primary concern was the environmental damage being caused by the breakdown of the galvanise.

The Service looked at using stainless steel or aluminium for the project and after all considerations, including cost, the decision was made to use grade 304 stainless for the posts and rails.

The job consisted of 263m of rail along around 90m of walkways, stairs, ramps and viewing platforms which snake through the cave.

Sinclair Knight Merz was engaged to design, seek tenders and supervise construction. The project presented some unusual and physically demanding challenges for the fabricator, Prins
Metalwork of Kingston.

COLD, DARK WORK

Adrian Prins and his firm worked on the project for two and half months, with a team of four or five people living at the caves for half that period.

All of the installation work, which was carried out in winter, had to take place at night so that the caves could stay open to visitors during the day. For the same reason, no voids were allowed to remain at the end of each session. The workers had to carry out all the old carbon steel balustrades by hand, just as they had to carry in all the new rails and their equipment, down 200+ steps into the cave.

Once inside they had to be very careful not to touch any of the formations, which are extremely fragile.

Because no angle grinding was allowed inside the cave for environmental reasons, they used a reciprocating saw to remove some 190 old posts.

The stubs were capped and the new posts installed. MIG welding was allowed, but kept to a minimum. There was only 240V, 10 amp power supply throughout the cave.

Where possible, fabrication took place at the workshop and was fine-tuned on site. The nature of the project meant that there were many adjustments to be made as few of the
balustrades have consistent angles. The concrete steps and landings, which were boxed in situ to adapt to the contours for the caves’ public opening in 1939, are quite irregular.

Sitework was carried out at the cave entrance, under artificial lights, in an area 400m from the carpark. It took the workers six trips along a boardwalk every night just to set up equipment
and they then had to carry materials and equipment up to 400m from the cave entrance.

While those who worked on the project recall the cold and the dark conditions, visitors can now safely enjoy the beauty of the cave in the knowledge that the new stainless steel infrastructure is protecting the caves and its visitors.

This article featured in Australian Stainless magazine - Issue 21, June 2002.


Posted 1 June 2002

At a time when so many industrial processes are computer-driven, there is still a place for human knowledge and experience in the highly specialised area of hydro-turbine manufacturing.

Steel Castings Pty Ltd, situated in Port Melbourne, has a reputation for precision moulding which has secured the firm contracts to produce two 'Pelton Runners' – the heart of the turbine – for a Victorian Hydro Power Station, working with the Norwegian designers, GE Australia and Acron Engineering.

Steel Castings have been making Peltons since the mid-90s. Measuring 2m in diameter and weighing in at 3.5 tonnes, these units are the largest so far. They are designed to withstand water cascading onto them from 400m above for 20 to 30 years to generate about five megawatts of electricity.

Despite their complex shape, the Peltons were cast in a single pour.

Technical Director Jim West explains the steps involved in achieving such a feat of engineering.

First a wooden pattern is made from drawings. Thousands of measurements must be checked. For example, there are 64 measurements for each of the Pelton Runner's 21 buckets. The pattern took about five weeks to make followed by a week of refinements.

One of the skills involved in pattern manufacture is estimating the contraction allowances for the shrinkage and distortions that occur during cooling and heat treatment. With only a 3mm tolerance window, this is something that can't be done by a computer, says Mr West. Once the pattern is complete, the mould and cores are produced from sand combined with a bonding agent – 17 tonnes of sand were required for this mould. The stainless steel used is CA6NM, a modified grade 410, poured at a temperature of nearly 1600ºC.

The mould is constructed so that the metal flows into all areas of the shape in less than 30 seconds of pouring time. The casting has to cool for seven days before it can be inspected. Then
the 'plumbing', the additional pieces which enable pouring the casting, is removed and the Pelton is heat treated at 1020ºC over a 23 hour cycle to strengthen the structure of the metal before final tempering and machining.

From drawing to installation the procedure takes about five months. The resulting finished technical marvel is worth hundreds of thousands of dollars.

ASSDA member Steel Castings Pty Ltd has its roots in the 19th century. It has operated in Port Melbourne since it was founded and employs a workforce of around 30 depending on current projects. The company's main business is manufacturing stainless steel and nickel-based alloy valves for the oil, gas and petrochemical industry. The firm also makes stainless steel ingots for the forging industry.

This article featured in Australian Stainless Issue 21 - June 2002.

Images:

Main image: mould nearing completion

Above right: cast detail of buckets


Posted 1 June 2002

The Australian construction and food processing sectors can specify stainless steel tube in large sizes with confidence in its quality and timely delivery, now that local production has commenced at a Victorian plant.

Manufacturing by an Australian firm will also make it easier for specificiers to communicate their special requirements.

Stainless Tube Mills' special purpose factory in Melbourne’s outer east is producing longitudinally welded tube in diameters up to 300mm and wall thicknesses up to 8mm – the largest seamwelded stainless steel tube available in Australia. Tube in this size range has always been imported.

The recently commissioned draw mill, designed in house by ASSDA member STM in conjunction with CSIRO, joins twelve other mills on site which produce welded tube up to 101.6mm outside diameter.

While a conventional mill uses a drive mechanism to feed the strip through the mill and produce welded tube, in the draw mill strip (1) is drawn through the mill with the forming rolls idling (2 & 3). This has the effect of producing a tube with minimal roll forming marks, as well as precise tolerances. The internal weld bead (4) is rolled to merge with the parent metal producing a smooth bore. Externally, the polished finish renders the seam all but invisible.

The smooth interior finish means tube produced on the draw mill is ideal for transfer of processing fluids, particularly food products, where the clean internal bore is mandatory.

Large diameter tube is also finding application architecturally for balustrades, barriers and structural column formers. As formers they make an attractive alternative to brick or concrete,
delivering a superlative appearance and impressive structural strength, which can be further bolstered by filling with concrete. STM used 300mm columns in T304 alloy to dramatically enhance its own office façade (left).

The draw mill has only been in operation commercially for a short time, however STM reports there has already been considerable demand. The firm's future plans include production of heavy walled large diameter sectional tubes for architectural applications.

This article featured in Australian Stainless Issue 21 - June 2002.


Posted 1 June 2002

A major new development project at the Jindalee Winery at Moorabool near Geelong utilises over 100 tonnes of grade 304 2B finish stainless steel. Shepparton’s J Furphy & Sons fabricated 95 wine storage and fermentation tanks, ranging in size from 75,000 to 1,200 litres.

The new tanks provide almost three million litres of temperature-controlled storage capacity for grapes processed from the adjoining vineyard and a much larger vineyard which Jindalee’s owners, Vince and David Littore, operate in the Murray Darling region near Mildura.

Three years ago the Littore Brothers acquired the former Idyll Vineyard and winery at Geelong which they are now using as the production centre for their wines produced under the Jindalee and Fettlers Rest labels for both local and export markets.

In addition to the tankage, most of which features the new Furphy Laser Welded Dimple Plate design which provides the cooling jackets to the tanks for circulation of refrigerants, Furphy’s have also completed more than 350 lineal metres of galvanised walkway and tank access systems.

Jindalee’s winemaker Scott Ireland describes the project as a state of the art winery facility designed to produce wines which will appeal to the most discerning palates as well as capitalising on and growing the export market success already achieved under the Jindalee label.

A $1 million bottling hall and packaging facility will be added providing a fully integrated facility.

This article featured in Australian Stainless Issue 21 - June 2002.

QUICK AND EASY TIPS FOR KEEPING THAT SHINE


Posted 1 June, 2002

Retaining a sparkling finish on stainless steel surfaces is just a matter of a few simple steps. And you don't need expensive products or special equipment - ordinary household cleaners are usually all that's required. You just need to bear in mind a few easy DOs and DON'Ts...

It'll come out in the wash

Stainless steel looks best if it's cleaned regularly with plenty of water. Drying afterwards makes sure streaky marks aren't left behind.

Remember that simply wiping with a damp cloth is not as effective as it can smear dirt without removing it.

Routine cleaning prevents any stubborn stains building up.

So what will you need?

You don't need any fancy equipment. For day to day cleaning, plenty of water, some mild detergent and a cloth or soft brush will do the job. You can use a 1% ammonia solution but don't use bleach? it's just too easy to make the solution too strong and too hard to rinse it properly afterwards.

After washing, rinse in clean water and wipe the surface dry with a soft absorbent cloth. On brushed stainless steel, follow the direction of the polish for best results.

An excellent cloth to use is 3M's Scotch-Brite high performance cleaning cloth.

Watch out for scratches!

The important thing to remember is that stainless steel can be scratched by careless handling or aggressive scrubbing. Just like you would take care of a polished timber finish, avoid dragging rough items across the surface and be aware that grit trapped under other objects can be the culprit.

Avoid bad chemistry

Stainless steel may discolour if left in contact with salts or acids for extended periods. Also avoid leaving carbon steel items in contact with stainless steel, particularly if wet. But if you observe ordinary hygiene measures, like timely cleaning-up in food preparation areas, you won't have any problems.

How to handle the tough customers

Sometimes you need a tougher approach. Here's how to get rid of the most common offenders:

Fingerprints, oil & grease marks

If a mild detergent or dishwashing detergent doesn't shift unsightly fingermarks, get rid of them with a bit of glass cleaner on a soft cloth. You can also use a small amount of alcohol, methylated spirits, acetone or mineral turpentine. Then rinse with clean water and dry.

You can give longer protection to high traffic areas by lightly rubbing with olive oil or baby oil followed by a polish and shine using a soft cloth.

Tea & coffee stains

Discolouration from tea and coffee stains can be removed by soaking in a solution of boiling water and baking powder. Remember to rinse well and wipe dry.

Sticky labels

Remove sticky labels as soon as possible. Gentle heat from a hair dryer or a glue gun generally softens the glue for easy removal, or you can warm stainless steel pots and pans in the oven before peeling off the labels. Eucalyptus oil based cleaners (or eucalyptus oil on its own) often work well to remove adhesives.

Ensure you don't leave any glue on the surface ? it could trap dirt or break down and cause staining.

Rust marks

Apply cream cleanser with a soft damp cloth and rub gently.

If the mark still won't shift, it might be necessary to use a proprietary stainless steel cleaner. These are usually based on dangerous chemicals (such as phosphoric, oxalic or sulphamic acids) and must be handled with care according to the manufacturer's directions.

After cleaning it is important to neutralise the acid with a 1% ammonia or baking powder solution, rinse with clean water and wipe dry. If the rust has worn away the surface, don't despair! Bad rusting can be repaired with professional polishing but you will need to get expert advice.

Paint

Apply paint stripper, taking care to follow the safety instructions. You may need to use a nylon brush or scouring pad, but avoid metal scrapers at all costs - they will damage the surface.

Hard water scale

Heavy limescale from hard water can be loosened by soaking in a hot water and 25% vinegar solution. Rinse well with a solution of baking powder or 1% ammonia and then with clean water. Always wipe dry.

Cement and mortar

Cement and mortar splashes should be washed off before they set. Mild acids such as vinegar may be needed but not those using chloride rich chemicals. Never use brick cleaning liquids which contain hydrochloric acid. Be very careful that loosened particles don't scratch the steel surface.

Don't go against the grain

Always rub stainless steel in the same direction as the grain. Rubbing against the grain will spoil the finish and stainless will lose its shine. Worse, rubbing against the grain can damage the surface by creating microscopic crevices where dirt can collect. This can lead to corrosion spots.

Fortunately, it's usually easy to tell which is the right direction. You need to watch out for items like round handrails, which are often polished around their circumference when they're manufactured, rather than up and down the length of the tube.

If you have to scrub a stain to remove it, make sure you use a clean nylon scourer or a cloth with chalk-based cream cleaner. But test an inconspicuous area first as you could end up with a bright polished spot which doesn't match the rest of the surface.

NEVER EVER use steel wool (wire wool) to clean stainless steel.

It is usually made of carbon steel and any fragments left behind will rust onto the stainless steel surface. Using any kind of scourer which has previously been used on ordinary (carbon) steel is also a no-no for the same reason.

Stainless steel wool scouring pads are available for heavy duty work, like removing burnt food from stainless steel saucepans. These will scratch the stainless steel surface, but won't leave fragments to go rusty.

Download Technical FAQ 2

Important Disclaimer

The technical recommendations contained in this publication are necessarily of a general nature and should not be relied on for specific applications without first securing competent advice. Whilst ASSDA has taken all reasonable steps to ensure the information contained herein is accurate and current, ASSDA does not warrant the accuracy or completeness of the information and does not accept liability for errors or omissions.

This article featured in Australian Stainless Issue 21 - June 2002.


Posted 1 June 2002

Melbourne's public life is populated with unique, strong and take-as-you-find personalities. Its culture – from high to mass – is influenced by figures like Jeff Kennett and Sam Newman, who shape Melbourne's view of itself and its environment.

While the former Premier's impact on the Victorian capital has been comprehensive, the refurbishment of Brighton Sea Baths as an upscale nightspot part-owned by Mr Newman has contributed a smaller scale landmark which is just as likely to provide visitors (male ones, anyway) with a memorable impression of the city.

The retired Geelong player and AFL Footy Show co-host, well-known in Melbourne for his flamboyant lifestyle, including a 5m high mural of pop icon Pamela Anderson at his Brighton home, came up with a quirky idea for the urinal: a built-in wide-screen TV (main image).

ASSDA member Britex, working with Buxton Constructions' Adrian Seymour and architects McGauran Soon Pty Ltd, were able to deliver the goods thanks to the versatility of stainless steel.

Melbourne's CBD has undergone a transformation in recent years, and everywhere stainless steel is playing a significant role. It’s proving its durability and appeal in major public facilities, such as Colonial Stadium (urinals) and Vodafone Arena (food preparation areas), both venues which showcase the city’s top sports events and attract many international visitors. The facilities must perform under the pressure of large crowds and yet look good.

Stainless steel fulfills these requirements here as it does at the Melbourne Convention Centre. The Centre, one of the country’s premier sites for international events, makes the most of its riverside location, with floor to ceiling windows framing views of the Yarra and one of Melbourne's best-known attractions, the Polly Woodside. Stainless steel benches in the foyer are in keeping with the clean lines and open spaces (see image, right).

Stainless works equally well in boutique refurbishments, such as Brighton Sea Baths and Retreat on Spring, an upmarket health resort tucked away near Melbourne’s gracious old Parliament buildings. The design language of Retreat on Spring is quiet, peaceful, harmonious.

Blond, polished floorboards, bamboo and stone set a tranquil tone. Stainless steel slips easily into this combination of natural elements and muted colours, while providing a practical surface in the health bar area and for the vanities in the individual therapy rooms.

From the intimate setting of Retreat on Spring to the high-traffic amenities at the city’s massive sports arenas, stainless steel is perfectly at home, providing both understated elegance and rugged performance.

This article featured in Australian Stainless Issue 21 - June 2002.


Posted 1 June 2002

Pressed stainless steel cladding has been used to spectacular effect on the Dame Roma Mitchell Arts Building of Adelaide Institute of TAFE, the training ground for many of Australia’s future performing and visual artists.

The originality of the design complements the creative nature of the activities housed in the building, situated on the edge of Adelaide’s Light Square.

Completed in December 2001, the four-storey complex comprises an art gallery, basement workshop facilities for ceramics and sculpture, two theatre spaces, and various studios and workshops.

Stainless steel fulfils a dual function. Not only does it provide aesthetic appeal, the pressed surface combined with the choice of finish is strongly resistant to the type of damage likely to
occur in a public building.

This world-class facility occupies a site area of 3,785m2 and has a total floor space of 15,500m2, but in spite of its bulk, a striking feature is its apparent light and transparency. The uninterrupted flow of the stainless steel panels from the external feature walls into the main foyer through the window-wall area creates amplitude. Reflections from the polished and
textured panels generate a play of light.

CONSTRUCTION

Each 0.45mm thick panel was unique and had to be manufactured and pressed individually. The interlinking design made it critical for all work to be executed satisfactorily from the outset, as it could not be rectified later. The real construction challenge lay in resolving the myriad detailing issues at the interface between the stainless steel and other elements.

This achievement – an Australian construction first – was a key factor in head contractor Hansen Yuncken gaining a high commendation at the Australian Institute of Building Professional Excellence in Building Awards. The Dame Roma Mitchell Building project team also included architects Hassell Pty Ltd and engineering firm Wallbridge and Gilbert.

Fabrication, by Donato Steel Fabrications Pty Ltd, was carried out in the workshop and panels were delivered to the site in specially constructed crates to avoid physical damage. Most of the approximately 2,000m2 of grade 304 stainless steel sheet was supplied by ASSDA member Atlas Steels Pty Ltd.

FINISH

Using a minimalist colour palette, the interior design relies for interest on the contrasting essential qualities of the materials utilised – glass, concrete and stainless steel. A finish combining high lustre and surface roughness (2B) was chosen for the stainless panels, providing a rudimentary feel sympathetic to the overall design. This choice has proven highly successful from both the aesthetic and maintenance perspectives, as it does not attract surface contaminants.

The result for Adelaide TAFE is a unique Australian landmark.

This article appeared in Australian Stainless Issue 21 - June 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

A decor has to be unique to stand out among the trendy cafes and nightclubs in Park Road, Milton, one of Brisbane’s most fashionable locations, and it certainly has to possess the wow factor to compete with the multitude of sensory experiences which greet clubbers out to see the latest bands and DJs.

A unique interior, using stainless steel, which would wow the patrons, was the brief SOBAR NightClub owner Darren Perris gave Brisbane fabricator Klein Architectural, along with just 48 hours for concept, design and installation before opening night.

The mission was accomplished with patterned stainless surfaces to capitalise on the venue’s electric blue lighting and generate myriad shifting reflections, creating the perfect high-energy setting for the pounding beats and sinuous rhythms of the nightclub scene.

Working within a budget of around $8,000, Klein used 13 sheets of 0.9mm thick, grade 304 stainless with a 2B finish, supplied by ASSDA member Fagersta Steels, to line the bulkhead and
square columns of the bar area. This was set off with 65mm round mirror polished tube at the rear of the bulkhead.

Following straightforward fabrication using glue and screwed fixings for the skinning, a heavy metal look was achieved by gluing the heads of cup bolts over counter-sunk screws.

Stainless panels on the columns were linished horizontally in a heavy grain and customised patterning was applied to the stainless steel skins of external and interior bulkheads and corners of the columns.

The end result is a shining example of stainless steel being used artistically and functionally without compromising either purpose.

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


Posted 1 March 2003

Lightweight stainless steel construction has allowed the proprietor of a Tasmanian cafe to expand operations without building new brick and mortar premises.

Page’s of the Mall is a stainless steel satellite to an existing cafe located in the busy Launceston Mall. Custom built for the site, it has proved popular and profitable since opening shortly before Christmas 2002.

The client, Mark Page, approached Launceston fabricator FAME Foley Industries with a particular brief: to construct a portable cafe catering to both take-away and sit-down trade which met standard refrigeration, food preparation and hygiene requirements. The unit had to conform to local Council guidelines and match the awnings recently installed in the Mall.

PACK UP AND MOVE

The challenge was to produce a design measuring just 2m high by 1.9m wide and 5.5m long to be wheeled into Page’s main shop at night.

The design evolved over the course of a year with input from a Launceston Council architect and took two months to build. The unit unpacks to a height of 2.5m when the roof is unfolded forming wing-like canopies above the serving areas, and the sides open out to 2.8m in width.

Concealed wheels at one end allow the unit to be moved using an electric pallet lifter. It is positioned over a pit with access via a hatch to water, power and drainage.

A seating area is enclosed by stainless steel barriers clad with laminex signs arranged in a zig zag shape for strength. These are also completely portable and have lockable castors.

Inside the cafe, which has garnered the nickname ‘coffee tram’, stainless steel pie heaters, fridges and washing facilities are built in as integral parts of the unit. Fully enclosed stainless steel trolleys are used to transport supplies from the main cafe.

PRACTICAL AND ECONOMICAL

Stainless steel was chosen for the project both for its clean style and for its appropriateness to the design and usage. The construction is simultaneously lightweight and strong, allowing it to be wheeled around daily and to withstand the mall traffic. Hygiene is readily maintained with easy to clean food preparation surfaces.

Most of the unit, including framework, walls, benches and supports are made from grade 304 stainless while grade 316 is used for the roof as it is exposed to the weather. The fridges, part of Foley’s range of kitchen and bathroom ware, are made from grade 430. Stainless steel was supplied by ASSDA member Atlas Steels.

Costs compare favourably with erecting a permanent building, at around $100,000 to construct and fit out, and the concept can be adapted to suit other locations.

The article featured in Australian Stainless Issue 24 - March 2003


Posted 1 March 2003

Our three-part series on coated abrasives concludes with information on choosing the correct abrasive product for the desired finish. Read Part 1. Read Part 2.

THE IMPORTANCE OF SURFACE ROUGHNESS

The surface roughness of stainless steel is an important factor in determining corrosion resistance. Put simply, the smoother the finish the greater the corrosion resistance, whether in the form of sheet or coil or in welded components.

SURFACE TOPOGRAPHY

Interaction between the abrasive belt and the workpiece is affected by surface topography (micro texture). Even a surface which appears perfectly flat to the naked eye has ‘asperities’, undulations between 0.05 μm and 50μm occurring 0.5μm to 5 mm apart.

A variety of instruments are available to measure surface micro texture. They work on the principle of moving a stylus over a representative length of the surface and recording the peaks and valleys.

In Australia, surface roughness is expressed in Ra. The measurement refers to the average variations of the undulations from the average surface of the sample.

Current density & surface roughnessTYPICAL FINISHES

Three stainless steel surface finishes are typically available from the mill:

  • #1 hot rolled, annealed and pickled (Ra 3 to 6μm)
  • 2B cold rolled (Ra 0.1 to 0.2μm)
  • BA bright annealed (Ra 0.06 to 0.2μm)

From these initial surfaces, a wide variety of finishes can be achieved with coated abrasives, satinising wheels and mops, buffing wheels and polishes. The type of finish generated depends on many variables: grit sequence, lubrication, raw material quality, machine type, abrasive type, pressure applied, through feed speed, abrasive belt speed and so on.

Because of all these factors, nominally identical finishes vary slightly from one producer to another. To ensure that the desired finish is delivered, specifiers should nominate the acceptable Ra (surface roughness) range and any other factors necessary for the application (for instance viewing angle or light conditions for architectural samples).

The common ASTM designations for stainless steel surfaces such as ‘No. 4’ specify a process to achieve a finish and not attributes of the surface itself. The result can fall outside the desired
surface roughness range. The Euronorm finishes of EN 10088, provide a larger number of specifications than ASTM A480 and include some which require particular Ra values.1

Although the measurements involved are microscopic, research indicates there is significantly higher resistance to corrosion in stainless surfaces with a roughness below 0.5μm Ra.

THE ROLE OF COATED ABRASIVES

Technically advanced coated abrasives are designed to optimise production by delivering consistent, measurable surface finishes. However, the operator must select the correct abrasives and the right product sequence.

Abrasive grainPolishing is hard work and even with machine operations, it takes time and care. The absolutely essential element is to remove all the polish lines from the previous stage before moving on to a finer grit. If this isn’t done, the final and finest buffing step will be marred by a streak on the surface. Although it is often impossible to rotate the work, removal of polish lines is readily
monitored by polishing at right angles for each new step.

The first grinding step should be as fine as possible. As #80 is usually the finest practicable size, it may require some time to smooth a large weld bead. An effective grit sequence for producing a mirror finish is 80, 120, 240, 320, 400, 600 and 800 before proceeding to mops.

Steps can be missed but at the cost of longer polishing times and the risk of stray scratches. Old abrasives will give a smoother finish but the results are less predictable and are operator dependent.

Lubricants may be necessary because of the poor conductivity of stainless steel. Lubricants also remove debris, improve the quality of the finish and increase the abrasive life. When buying abrasives it is important to choose a reputable product; an unknown quality could mean stray, coarse grit with its attendant final streaks which will mar the result and be especially obvious on a ‘mirror’ finish.

When silicon carbide abrasives are used a brighter, more highly reflective finish results, albeit at the expense of belt life. Other materials, for example aluminium oxide, zirconia or ceramic
grains, will give a significantly longer belt life but will produce a different overall finish.

A quality coated abrasive belt acts as a series of single point cutting tools. Each grain has the optimum shape and angle to accomplish the cutting action and subsequent chip removal. This is partly achieved through electrostatically orienting the grains in relation to the backing during manufacture. The rest comes from choosing the correct abrasive type for the job. A cutting facet which isn’t sharp enough results in random streaks on the stainless steel surface as the grain fails to cut cleanly and drags a chip along the surface. This effect is more prevalent with aluminium oxide belts.

Roughness vs Abrasive Grit Size*

Grit
Ra(μm)
500# 0.10 - 0.25
320# 0.15 - 0.22
240# 0.30 - 0.67
180# 0.42 - 0.96
120# 0.29 - 0.81
60# 2.01

GETTING IT RIGHT

Supplying the desired surface is as much a part of filling a contract as other aspects of fabrication. There are a large number of variables which impact on the surface finish. The previous two issues of Australian Stainless presented an overview of modern coated abrasives and specific information on their composition and manufacture (issues 22 and 23). Data on the hardness of abrasive materials and a relative comparison of grit size was included.

An understanding of what makes a quality abrasive product and how coated abrasives interact with the workpiece helps ensure that the corrosion resistance and aesthetic requirements of
the client are met.

1. EN 10088-2 : 1995 specifies additional specific requirements to a ‘J’-type finish, in order to achieve adequate corrosion resistance for marine and external architectural applications. Transverse Ra < 0.5μm with clean cut surface finish.

This article featured in Australian Stainless Issue 24 - March 2003. It was written by Charles E. Fenton, Managing Director of Klingspor Abrasive Technologies, Australia and Graham Sussex, ASSDA’s technical specialist.


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 May 2004

Choosing mainline fittings for irrigation applications can often seem like building a giant puzzle with elbows, tees, crosses and coupler sets - various fittings required to connect irrigation pipework together.

Pierce AustraliaHowever, Geoff Mellows from Yarrawonga Irrigation in Victoria may have solved the puzzle by using stainless steel mainline fittings - something that plastic fittings cannot yet match.

Poly, pvc and avs fittings are common materials in irrigation applications but because they are produced out of a mould, the combinations of size and outlet configuration are restricted.

Mellows said that by using stainless mainline fittings by ASSDA member, Pierce Australia, he can now “manipulate the angle, the shape, the variation and combination of outlets.“

The difference is simple. PVC and poly are bolted on, or welded and glued - making it difficult to change fittings”.

Stainless steel mainline fittings are the only rubber-ring jointed fittings available on the marketplace manufactured to the customers specific needs and can be fitted on any other combination because they are fabricated.

Stainless steel mainline fittings also provide flexibility of design in the angle of the fittings.

This also applies to the combination of outlets on those fittings and any other additional connections to that fitting.

With versatile stainless steel fittings, Mellows advice to customers is simple - “lay the pipe first and worry about the fittings later!”

This article featured in Australia Stainless Issue 28, May 2004.

Photos courtesy of Pierce Australia.


Posted 1 May 2004

The Australian War Memorial in Hyde Park Corner, London stands as a symbol of freedom and an enduring spirit of strength.

To commemorate the men and women who fought and died for Australia alongside Britons in the two World Wars, Australian architectural firm Tonkin Zulaikha Greer and artist Janet Laurence designed the Memorial to reflect the sweep of the Australian landscape.

The result was a highly durable structure featuring a long, curved wave wall constructed out of West Australian green granite and supported by grade 316L stainless steel.

ASSDA Major Sponsor, Atlas Specialty Metals, and ASSDA members, M & S Stainless Supplies and Dalsteel Stainless supplied approximately 9000 kilos of stainless steel for the structure including 8mm plate, pipe, angles and 3mm sheet.

Grade 316L was specified for its corrosion resistance, particularly as the Memorial comprises a water feature that periodically cascades water across the wall to highlight the names of the hometowns of our soldiers.

Stainless steel was used primarily in the construction of stainless steel cradles which were fabricated in Australia, shipped, positioned and lifted into place to support the granite.

All welds were pickled and passivated to provide protection from the bromine and chlorine’s likely to be deposited on the frames from the water forms built into the Memorial.

Australian-based firm Design and Survey Neon (DSN) played a leading role in the design and manufacture of the supporting structure by using 3D modelling techniques.

The 3D modelling allowed the manufacture of components and assembly of the job to become a seamless process.

DSN modelled the granite wave wall and supporting cradles. The templates for the granite blocks and their fixings were then lifted from the model to enable the fixings to be pre-drilled prior to assembly.

The use of laser cutting and CNC technologies allowed DSN to fabricate to near machining tolerances. Laser etching of assembly notches were added for simple fabrication and installation.

Coordinates for supporting cradles from the model were used to determine correct on-site positioning via electronic theodolites.

The granite blocks were positioned with a 6mm gap vertically and horizontally to a tolerance of plus or minus 1mm. Precise accuracy was required to avoid accumulation of errors because of its wave like design.

Most of the components for the Memorial were imported from Australia. Water features and water effects were created by Waterforms International and all the stone work was assembled by Australians.

This article was featured in Australian Stainless Issue 28, May 2004.

Photos courtesy of Department of Veteran Affairs & Design and Survey Neon (DSN).

Main image: The Australian War Memorial 'Dedication Day Wreaths' placed in front of the curved granite wave wall. Photo courtesy of the Department of Veterans Affairs, copyright Commonwealth of Australia. Reproduced by permission.

Other images: 316 stainless steel cradles were lifted into place to support the granite blocks that form the wave wall.