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Style + Strength

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 Stainless steel was the best way to go - its clean lines never go out of date."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.

Coated Abrasives for Surface Finishing - Part 1

Accurate specification of a surface finish is vital for extracting maximum functionality and durability from stainless steel components. Read Part 2. Read Part 3.

Coated abrasives are important in generating the right surface finish for corrosion resistance, cleanliness, aesthetics or other requirements.

MANUFACTURING PROCESS
Primary manufacturing processes such as casting, forging or rolling produce a surface finish which may be adequate for the end function. If not, there are secondary processes such as machining, cutting, grinding, lapping or mass finishing using tumbling techniques or barrel finishing.

Surface finishing techniques may be mechanical, electrical, thermal or chemical or a combination. The finish depends on grit size, pressure and
product selection.

COATED ABRASIVES
Coated abrasives in the form of belts, rolls or discs are used during both the primary and secondary manufacture of stainless steel into coils, sheets or fabrications. Methods and machinery may vary but the broad principles are:

> do not abrade unnecessarily – start at the finest grit which will produce the desired finish quickly

> never skip more than two grit sizes in a polishing sequence or previous grit lines cannot be removed

> don’t use excessive pressure – coated abrasives cut well with minimal pressure

> don’t persist with a worn abrasive product – when a disc or belt stops cutting it should be replaced.

DEVLOPMENTS
The drive for better manufacturing has yielded improvements to grinding and polishing machinery, accompanied by developments in abrasive products. Better abrasive grains give faster stock removal and longer life which has led to increased horsepower being specified and this has necessitated improvements to the quality of backing materials.

COATED ABRASIVES AND SURFACE FINISH GENERATION
A coated abrasive has three components – backing, adhesive and grain – each of which affects the outcome.

BACKINGS are manufactured from paper, cloth, fibre or a combination, non-woven material or polyester film. The type selected should:

> have sufficient tensile strength to transmit the power loading of the machine

> be flexible enough to conform to component shape

> provide a substrate suitable for the relative strength of adhesive required

> not stretch unduly during use

> in the case of very fine grit coatings, provide a flat and true surface.

Paper backings come in a variety of weights designed for specific tasks. In the stainless steel market belts are most commonly manufactured in E (180-200gsm), F (230gsm) or G (300gsm) weights. They may also have anti-static surface treatments to minimize dust adherence.

Cloth backings come in many varieties. Most commonly, X weight (cotton) and Y weight (polyester) are used in heavier stock removal operations such as the grinding of castings and J weight, which is lighter and more flexible, is used for contour work – polishing complicated shapes. Different cloth backfills applied to the rear of the coated abrasive belt allow it to be used for dry and wet operations (oil or water) according to the type of operation.

Cloth belts are normally used on higher horsepower machines and need to be strong enough for the transmission power which can be as high as 10HP per inch width of belt (7.5kW per 25mm).

Vulcanised fibre is used extensively in the manufacture of resin fibre discs. It is less flexible than paper and cloth backings but has the strength required to withstand high operational speeds and heavy grinding pressures.

Combination backings consist of an E weight paper reinforced with an open weave cotton scrim cloth. They are usually used for very coarse grit operations.

Non-woven backings such as lofted nylon are used in the manufacture of hand polishing pads and rolls. This material also forms the basis of many convolute wheels and flap brushes (pictured) which are used to impart a special brushed finish.

BONDING ADHESIVES are used to anchor the abrasive grains in place on the backing. They can be natural animal glues but thermosetting synthetic resins are the norm. They are stronger, tougher and resist heat and fluids better. Different types and strengths have been developed according to the product’s end use. As a rule of thumb, if belts or discs are shedding (losing grain) then the bond strength needs to be increased; if the product is showing signs of glazing (metal pick up) then the bond needs to be less strong.

ABRASIVE GRAINS Most of the grains in use today are synthetically manufactured to be hard enough to penetrate the substrate being ground while still fracturing under dynamic impact to present new cutting facets. They are designed for high thermal and chemical resistance at grinding interface temperatures.

Premium grade aluminium oxide grains are an effective general purpose abrasive. Silicon carbide grain is used to impart a brighter finish, however it has a comparatively shorter product life. Although more expensive, the newly-developed zirconia alumina grain produces a more consistent finish throughout the life of the product.

Words by Charles Fenton. Charles E. Fenton is Managing Director of Klingspor Abrasive Technologies, Australia. The next article in this series will look at how backings, bonding adhesives and abrasive grains are combined.

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

A Safe Surface for Food Processing

A contaminant-free surface is a critical requirement of the food processing sector and electropolishing is a highly effective way to achieve the level of surface smoothness required for keeping stainless steel components scrupulously clean. 

Pillsbury Australia in Melbourne's outer east is one of a growing number of food processors who have opted for electropolishing for hygienic and durable stainless steel components. Pillsbury produces the fresh pasta brand Latina Fresh. The range consists of filled pasta types like ravioli and tortellini for which the fillings are cooked during manufacture, but the consumer completes the cooking process at home. For some years now, Pillsbury has specified an electropolished finish for all its stainless steel food preparation equipment and related components such as trolleys, cooling racks and other fittings. These are manufactured by GP's Fabrications and electropolished by ASSDA member MME Surface Finishing.

As well as promoting hygiene, electropolishing enhances stainless steel's corrosion resistance. Many fittings in Pillsbury's plant have been in constant operation for eight to ten years and show no sign of surface deterioration despite exposure to steam-laden, high temperature atmospheres.

Electropolishing works by selectively removing surface metal thereby smoothing and levelling the stainless steel. This is done by immersing the component in a chemical bath to which lowvoltage electric current is added. Stock removal is controlled to a high degree of accuracy by adjusting the time, temperature and current density.

The resulting finish is free of surface flaws and impurities, giving no opportunities for deposits to lodge and contaminate the food product. A further benefit is that it makes the components easier to keep clean, allowing for longer periods of processing activity.

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

Australian Technology Advances Industry

A new technique for manufacturing high pressure cavity plate for heat exchange applications developed by the Australian stainless steel industry increases the options available to the food processing and manufacturing sectors. 

'Laser welded cavity plate' has been developed by ASSDA member J Furphy & Sons, a Shepparton fabricator of stainless steel tanks and processing equipment, as an alternative to resistance or plug welded dimple plate used for the heating or cooling jackets on stainless steel tanks, vessels and silos.

A wide range of industries stands to benefit from the new cavity plate, from dairy, brewing, food, wine, pulp and paper, chemical, pharmaceutical, refrigeration to textiles and manufacturing.

It is designed to be used in jacketed tanks, pressure vessels, shells and heads, troughing, chutes and hoppers, immersion plates, bank assemblies, baffles, ice-making plates, water chillers and food cookers.

The method of manufacture allows design flexibility enabling it to be tailored to specific performance requirements. It can be designed to suit both the flow characteristics of the refrigerant or heating medium and the required performance objective for the equipment by programming the cavity pattern and dimensions into a CNC controlled laser welding system.

The process involves laser welding two sheets of stainless steel in their flat form and inflating to form the cavity through which the cooling or heating medium is transferred.

The laser welds are exceptionally strong and have been burst tested in excess of 13 000 kPa, with most common demand being for operating pressures between 300 and 3 000kPa.

The product is available single embossed for uses where a flat inner wall is required or double embossed for immersion where both sides of the plate are utilised to heat or chill.

It is in use in chocolate crucibles in the confectionery industry as well as in Peerless Holdings’ edible oils processing tanks. Orbis Engineering has used the cavity plate in a cooling tunnel conveyor bed and Barry Brown & Sons has utlised it in on-farm milk silos. It has also been used in various major winery projects, including Peace Wines and Jindalee Estate, for fermentation and storage vessels.

Another ASSDA member, A&G Engineering of Griffith, has specialised in cavity plate for use as a cooling plate in wine vessels for a number of
years. This product also incorporates technology unique to Australia.

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

Stainless Takes Flight

Lightweight stainless steel sheet, polished to a high level of reflectivity, has been chosen to interpret the layered feathers of one of Australia's national icons, the dancing brolga. 

Designing and creating a trio of life-size sculptures has occupied much of Allen Minogue's time since his retirement as an engineer and designer.

The birds, inspired by a visit to the Northern Territory, have cast grade 316 legs and heads and feathers made from 2B finish 316 sheet in four
thicknesses, from 0.55mm to 1.2mm.

The feathers are all individually shaped using a hand guillotine and other hand tools. They are then screwed into a fibreglass body moulded from a wooden carving. The first figure, which took 700 hours to complete, has 700 feathers. The poses are realistic, with the central male bird
captured at the moment of taking flight.

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

 

Stainless Memorial to Rail Workers

Stainless steel responds admirably to the strength and durability imperatives of public art at the Ipswich Workshops Rail Museum, opened to the public earlier this month.

The Workshops began operations in the 1860s and initially assembled components imported from England, but by the early 1900s railway stock was being manufactured from the ground up. During the peak employment period of the 1950s there were over 3 000 workers. To reflect the Workshops’ importance in shaping the identity of the town of Ipswich, west of Brisbane, the design brief called for a monument concentrating on the social history of the Workshops and the contribution of the vast number of workers, interpreted in a contemporary framework.

In response, Brisbane sculptor Brad Nunn designed MARKER, a curving stainless steel column bearing the words spirit and presence,studded with numbered discs representing individual workers.

Each worker had a disc resembling a dog tag known as a check, which he collected from the foreman on arrival at work. He used the check throughout the day, for example to borrow tools, and returned it when clocking off. Railway authorities calculated the workers’ pays by seeing which checks had been collected each day.

Nunn obtained a first-hand account of life at the Workshops from his father, an apprentice there in the late 1940s. He chose the text to communicate the strong spirit of place he felt when touring the Workshops and selected a photo of payday, 16 July 1924, which was reproduced at eye-level using laser marking to retain tonal variations.

Nunn, who has been practicing artist since graduating from the Queensland College of Arts in 1990, has previously designed public artworks
using aluminium. He chose stainless steel for this project because it fulfilled the brief’s requirements for durability, longevity and vandal-resistance.

Fabrication of the sculpture was carried out over 300 hours by two staff members of ASSDA member Stoddart Metal Fabricators. The 3m high structure weighs about 1 tonne. Grade 316 plate in 10mm thickness was used; the hundreds of round recesses were milled out and the column bead-blasted and finished with a no.4 vertical polish. Approximately 600 checks are attached to the sculpture and another 600 appear to have been dislodged and are glued to the concrete base around MARKER.

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

New Technology for Design Excellence

The overwhelming response from the architecture community to our earlier article on precision folding of stainless steel sheet using vee-cutting technology has prompted a more in-depth look at the process. 

Thanks to vee-cut technology, stainless steel sheet can be formed into angles as precise as those obtained by extrusion. This technology is now being carried out in Sydney, allowing the local manufacture of a whole range of stainless steel architectural products. The technique is particularly suited to elements such as door fronts, window frames, shopfronts, showcases, elevator doors as well as all forms of cladding.

In a completely new method of manufacture, vee-cutting can also be used to make flat products such as tread plates for lifts and escalators by removing strips of material to the required width and depth.

CLEAN LINES COMPLEMENT SPECIAL FINISHES
Ordinary bends made on a brake press typically produce a corner radius twice the thickness of the sheet, resulting in a finished product with soft, blurred lines. But with the introduction to Australia of vee-cut technology, it is now possible to produce stainless steel with corners as precise as an extruded angle, such as those found on aluminium window frames.

The method is particularly useful when working with textured and patterned stainless sheet. Such finishes are distorted by the traditional bending method. Using the vee-cut machine, the feature finish is preserved without loss of quality. This makes it the manufacturing method of choice for items such as bar fronts, display cases, door furnishings and a myriad of other uses where appearance counts.

THE VEE-CUTTING PROCESS
The machine cuts a continuous vee-shaped notch in the sheet using a series of five tools, which make repeated passes across the surface. The number of passes required varies depending on the thickness of the metal; generally three or four are needed, but up to 15 can be required for thicker product.

The machine can handle thicknesses in the range of 0.6mm to 6.0mm and is capable of cutting to a minimum depth of 0.4mm and processing sheet up to 4m in length. The sheet is then folded along the groove in a brake press. The depth of the groove can be set for acute angles down to 15°.

When used for cladding, up to 70% of the thickness of the sheet can be removed; however, care needs to be taken not to weaken structural components by removing too much of the thickness. One option is to remove material to obtain a tight corner and then stitch weld to restore strength – it is a matter of weighing up cost and other considerations.

A TYPICAL APPLICATION - ENTRANCE DOORS
An example of the finish available can be seen in the revolving doors of the McKell Building in Sydney (pictured). Byrnes Entrance Technology Pty Ltd (BET) worked with ASSDA member the Townsend Group to produce profiles and folded panel sections to clad the central steel and aluminium core of the triple door. The final effect is the appearance of a solid, triangular-shaped central column with lightly inward-curving sides.

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

Stainless, Sun and Air

Stainless steel is well-known as a versatile and attractive medium for large scale public artworks. Two recent projects by Perth’s Stusha Studio make use of different treatments of the material to deliver attention-grabbing results.

INSPIRED BY NATURE
The Armadale Kelmscott Memorial Hospital in WA commissioned shade structures in two courtyards and Stusha Studio responded with four elements, representing a flower, a seed, a leaf and a fruit, inspired by the orchards of the area and the seasons. The structures provide a shadow-play on the courtyard floors and walls, blushing the areas with shade.

The elements are made of stainless steel mesh, rod and square tube and are suspended at 4.4m. The material supply of grades 316 and 304 and support from ASSDA member Stirling Stainless Steel was crucial to the production of the work, fabricated at Stusha Studio and Art Engineering.

As the shades were installed after the hospital was complete, they were made in sections and re-assembled like a kite inside the courtyards. Because the rib-work for the shade structures was garnet-blasted, installation required care to avoid scuffing and this was provided in ample amounts by Damien Costello at Tension Structures.

COLOUR AND MOVEMENT
Hale School in Wembley, WA commissioned a sculptural interpretation of the theme ‘young hearts run free’. Stusha Studio created four stainless steel winged figures, grounded in four points but able to move with the wind, suggesting freedom no matter what the conditions.

The figures are on internal bearings that allow the whole structure to respond to the breeze. Because of their different dimensions the figures move at varying rates, producing an ever-changing kinetic sculpture.

The wings are made entirely of grade 304 stainless steel, cold forged under the largest hammer in the southern hemisphere at Ferrous Forging in Sunshine, Victoria. The sheets were heated by torch, rippled and fabricated by Kevin Burnett at Red Falcon in collaboration with Stusha Studio, in Melbourne. The wings were then shipped to Perth and combined with the rotating shaft, designed by Michael Ong and machined by Medical Engineering.

STAINLESS FOR PUBLIC ART
In carrying out these and other commissions, Stusha Studio has chosen to use stainless steel to deliver artistic concepts because of its robust quality and the easy access to technical advice and expertise. As an artistic material, stainless steel is versatile in the decorative treatments it supports. Text and graphics can be etched into the surface and paint filled if desired, while forging opens up a whole range of colours and effects.

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

Walking on Water

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.

Stainless Braves the Elements

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.

Sheer Delight

Stainless Steel Mesh

Woven metal fabrics are a popular architectural product in Europe, where stainless steel mesh is used for a high-level finish in many internal and external settings, such as wall and ceiling panelling, space dividers, external cladding and facades.

Now Sydney firm Interspace Manufacturing Pty Ltd is making and installing woven stainless steel wire mesh screens using metal fabrics from iO Metal Fabrics Pty Ltd, a German firm with an Australian presence and a member of ASSDA.

ASSDA member Interspace has been designing and manufacturing store fittings and custom fixtures for displays and exhibitions since 1970. The firm began utilising stainless steel mesh two years ago and has produced partitions for a number of interiors, including the AMP Building in Sydney and the office of medical supply firm B. Braun, designed by Leffler Simes Architects. Another project is Space 207 in St Leonards, Sydney, which is being billed as "the North Shore's finest office building, so advanced it is destined to lead the way in business premises for a long time to come." The designers of Space 207 set out to create an environment representing "style, sophistication and elegance" and chose stainless steel mesh to complement the building's hi-tech, ultra-modern decor.

Woven stainless steel fabrics are versatile and reliable. Made from corrosion-resistant grade 316 stainless, they are equally at home in hostile external locations requiring stainless steel's hard-wearing capability and in internal spaces where aesthetic values come to the fore. They can be put to a variety of uses, including partitions, wall and ceiling cladding, awnings and sunscreens. In Germany they are also employed in roadside noise reduction barriers.

Stainless mesh is lightweight but strong and it is extremely resilient when subjected to environmental threats such as heavy weather, fire and chemicals.

Like textiles generally, metal fabrics are woven on a loom, producing an attractive array of patterns and textures in a varying degrees of weight and flexibility.

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

Stainless preserves Tasmania's heritage

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.

Stainless for power generation

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

Large tube now made in Australia

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.

New winery development

 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.

Cleaning your indoor stainless steel

Quick and easy tips for keeping that shine

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.

Stainless across a cultural spectrum

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.

Adelaide Landmark Resplendent in Stainless

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.

Coated Abrasives for Surface Finishing - Part 2

The last issue of Australian Stainless contained an overview of coated abrasives and guidelines for achieving the desired surface finish. This technical series continues with a comparison of grit size and hardness. Read Part 1. Read Part 3.

Early versions of abrasive sheets and rolls were made by sprinkling naturally occurring grit, such as sand or emery, onto cloth or paper coated with animal hide glue. The resulting 'sandpaper' was used for surface finishing in woodwork or preparing a surface for paint or varnish. Because the application of the grit was random the product soon became dull and lost its cut.

Not long after the development of paper products, the flexible emery cloth roll made its appearance in metal working workshops as a standard tool for rust removal and light finishing. By contrast, solid bonded grinding wheels were developed for heavy stock removal in foundries.

3 Elements: Backing, Bond and Grain
Modern coated abrasives allow stock removal up to 30 times faster than with a bonded grinding wheel. This superior performance has been brought about by improvements to all three elements of coated abrasives: backing, bond and grain.

Backing
The type of backing used sets the basic design parameters, being: strength, safety, shape, geometry, tolerance and coolant resistance.

Paper - available in various weights up to 300 gsm (grams per square metre) in widths up to 1650mm.

Cloth - cotton, polyester or a mixture, in widths up to 1550mm.

Fibre - 0.7mm (30 thou) vulcanised fibre.

Combination - linen scrim cloth plus paper in widths up to 1000mm.

Polyester film - flexible consistent thickness.

Bond
Natural glues can be used for the matrix supporting the abrasive grain but modern abrasives generally use synthetic thermosetting resins which are stronger, tougher and more heat resistant.

Grain
Abrasive grain provides the cutting edges for surface generation. Common types are:

> Aluminium oxide AI203 available with various surface treatments
> Silicon carbide SiC
> Zirconia Zr02
> Ceramic aluminium oxide SG (seeded gel).

The important characteristics of grain are hardness, friability, toughness and shape.

The graph below shows the hardness of selected materials including abrasives.


Relative Comparison of Grit Size
The selection of the correct grit size and sequence is vitally important in achieving the desired surface finish. The most common grading system in use today is the FEPA or 'P' series (Federation of European Producers of Abrasives).

However, certain products made in the US or Japan may be graded differently. Equivalents are provided in Table 1.

Abrasive Production
The majority of abrasive manufacturers employ a reel to reel process to combine the backing, adhesive bond and grit into an efficient cutting tool.

As shown below, he grain is propelled into the wet adhesive by means of an electrostatic force. This critical part of the manufacturing process ensures a sharp, long lasting product. In order to further secure the abrasive grain, an additional coat of adhesive, known as a 'size' coat, is applied and the whole product is dried and cured. Certain products (called multi-bond or super-sized) have a further coating applied in order to minimise heat build up and subsequent welding action. This feature is particularly important in the case of stainless steel grinding because non-oxidised steels are very reactive at interface grinding temperatures and they combine readily with the aluminium oxide grain. This phenomenon is visible as a silvery sheen on the surface of an abrasive belt. Once the grain has been 'capped' with metal it can perform no further cutting action and merely increases frictional heat and subsequent degradation.


Using Abrasives Economically

There are a number of factors to be considered to obtain best value from coated abrasives. If obtaining a specified, repeatable finish is an important consideration it may be most economical to limit the abrasive belt to a set amount of polishing, for example a certain number of metres of coil. If specific finish is not a criteria the abrasive can be used to the very end of its life. Saving time or power usage and utilising the most technically advanced product can be as significant overall as the amount of abrasive consumed.

 

Table 1 - Relative Comparison of Grit Size

Particle size inches Particle size microns All product other than emery Emery
Grading system Comparable grit symbol Polishing paper Cloth
CAMI FEPA
0.00026 6.5 1200 - - 4/0 -
0.00035 9.0 - - - - -
0.00036 9.2 1000 - - 3/0 -
0.00047 12.0 - - - - -
0.00048 12.2 800 - - - -
0.00059 15.0 - - - - -
0.00060 15.3 - P1200 - - -
0.00062 16.0 600 - - 2/0 -
0.00071 18.3 - P1000 - - -
0.00077 19.7 500 - - 0 -
0.00079 20.0 - - - - -
0.00085 21.8 - P800 - - -
0.00092 23.6 400 - 10/0 - -
0.00098 25.0 - - - - -
0.00100 25.75 - P600 - - -
0.00112 28.8 360 - - - -
0.00118 30.0 - P500 - - -
0.00137 35.0 - P400 - - -
0.00140 36.0 320 - 9/0 - -
0.001575 40.0 - - - - -
0.00158 40.5 - P360 - - -
0.00172 44.0 280 - 8/0 1 -
0.00177 45.0 - - - - -
0.00180 46.2 - P320 - - -
0.00197 50.0 - - - - -
0.00204 52.5 - P280 - - -
0.00209 53.5 240 - 7/0 - -
0.00217 55.0 - - - - -
0.00228 58.5 - P240 - - -
0.00230 60.0 - - - - -
0.00254 65.0 - P220 - - -
0.00257 66.0 220 - 6/0 2 -
0.00304 78.0 180 P180 5/0 3 -
0.00363 93.0 150 - 4/0 - Fine
0.00378 97.0 - P150 - - -
0.00452 116.0 120 - 3/0 - -
0.00495 127.0 - P120 - - -
0.00550 141.0 100 - 2/0 - Medium
0.00608 156.0 - P100 - - -
0.00749 192.0 80 - 0 - Coarse
0.00768 197.0 - P80 - - -
0.01014 260.0 - P60 - - -
0.01045 268.0 60 - 1/2 - -
0.01271 326.0 - P50 - - -
0.01369 351.0 50 - 1 - Ex. Coarse
0.01601 412.0 - P40 - - -
0.01669 428.0 40 - 1-1/2 - -
0.02044 524.0 - P36 - - -
0.02087 535.0 36 - 2 - -
0.02426 622.0 - P30 - - -
0.02488 638.0 30 - 2-1/2 - -
0.02789 715.0 24 - 3 - -
0.02886 740.0 - P24 - - -
0.03530 905.0 20 - 3-1/2 - -
0.03838 984.0 - P20 - - -
0.05148 1320.0 16 - 4 - -
0.05164 1324.0 - P16 - - -
0.06880 1764.0 - P12 - - -
0.07184 1842.0 12 - 4-1/2 - -

Words by Charles Fenton. Charles E. Fenton is Managing Director of Kongspor Abrasive Technologies, Australia. The next article will look at specific finishes and their generation using coated abrasives.

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

Stainless Enclosures Built to Last

Australian-made weighing technology is the first choice for global giant Caterpillar Inc., the world's leading manufacturer of construction and mining equipment.

Local firm Transcale, designers and manufacturers of electronic weighing equipment specifically for the mining and transport industries, exports its equipment worldwide to over 11 countries in North and South America, Southern Africa and South East Asia.

Transcale's focus on the mining sector means that cutting edge technology needs to be protected from some of the harshest environments in the world. Extremes of heat and clod, record rainfalls, drought, high salt or other corrosive minerals are just a few of the considerations in the design process. Transcale's equipment is housed in stainless steel enclosures.

Over the last six years Transcale has used both 'off the shelf' boxes from companies such as ASSDA member B & R Enclosures, and custom-built stainless steel enclosures. One of the custom-built enclosures manufactured by MT Sheet Metal in Archerfield, Brisbane uses a 316 N4 brush finish stainless steel supplied to MT by ASSDA member Atlas Steels. B & R Enclosures also manufactures its high performance enclosures using grade 316 stainless with an N4 finish and fully welded body to withstand corrosive atmospheric conditions.

Both Transcale and its customers report that they are impressed with the long-term performance of these enclosures. According to Transcale, investing just a few extra dollars up front by choosing stainless for their enclosures produces tangible rewards by way of repeat business and an enhanced reputation.

For example, one of Transcale's major clients, US-based Caterpillar Inc., recently stated its intention to use Transcale truck scales exclusively for all replacement systems in its mining departments globally. Caterpillar's considerations for choice of product were quality and reliability along with appearance and after sales support.

In Australia, a major interstate line haul company has just taken delivery of a third Transcale dynamic axle weighing system, giving it a unit in Melbourne, Sydney and now Brisbane. In Brisbane the system has been installed at the Port of Brisbane facility, where salt air was one of the considerations. This system is protected from the elements by an MT Sheet Metal enclosure.

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