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Foundries and Furnaces

melting steel

According to Wikipedia, a foundry is a factory that produces metal castings. Metals are cast into shapes by melting them into a liquid, pouring the metal in a mold, and removing the mold material or casting after the metal has solidified as it cools. The most common metals processed are aluminum and cast iron. However, other metals, such as bronzebrasssteelmagnesium, and zinc, are also used to produce castings in foundries. In this process, parts of desired shapes and sizes can be formed.

At 21st Century Steel Mill, Incorporated, we do not have a foundry but we have a furnace.  Furnaces are refractory-lined vessels that contain the material to be melted and provide the energy to melt it. Modern furnace types include electric arc furnaces (EAF), induction furnacescupolasreverberatory, and crucible furnaces. Furnace choice is dependent on the alloy system quantities produced. For ferrous materials EAFs, cupolas, and induction furnaces are commonly used. Reverberatory and crucible furnaces are common for producing aluminium, bronze, and brass castings.

Furnace design is a complex process, and the design can be optimized based on multiple factors. Furnaces in foundries can be any size, ranging from small ones used to melt precious metals to furnaces weighing several tons, designed to melt hundreds of pounds of scrap at one time. They are designed according to the type of metals that are to be melted. Furnaces must also be designed based on the fuel being used to produce the desired temperature. For low temperature melting point alloys, such as zinc or tin, melting furnaces may reach around 500° C. Electricity, propane, or natural gas are usually used to achieve these temperatures. For high melting point alloys such as steel or nickel-based alloys, the furnace must be designed for temperatures over 1600° C.

In short, it’s really HOT!

Categories: Innovation, Uncategorized

Innovative steel architecture and engineering shine at 2014 National Steel Excellence Awards in Australia

Article from Architecture & Design Australia

Star City Events Centre by Brookfield Multiplex, ICPM and Taylor Thomson Whitting, and designed by Fitzpatrick + Partners, won the Buildings – Large Project category. Sitting atop of the existing casino, the facility comprises over 1,000 tonnes of new structural steel, and is a braced steel frame supported on eight existing columns and two new columns positioned between two post-tensioned transfer beams.

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The internal floor structure hangs from an external ring truss, which transfers back to the primary columns. Site bolting was utilised for the connection of prefabricated elements across the site, reducing onsite welding to an absolute minimum.

“[Star City Events Centre] is an elegant solution especially difficult on an existing structure whilst it was still operational, involving a high degree of team coordination,” the jury commended.

Teamwork was also central to the Scenic Railway Upgrade in Katoomba, NSW, which was awarded the Engineering Projects category top prize. Submitted by Jacobs SKM, the project prominently employs steelwork to upgrade the railway, listed by Guinness Book of Records as the world’s steepest.

A 3D laser survey of existing structures allowed for accurate modelling to deal with the loose and environmentally sustainable terrain, leading to an innovative use of steel casing in micropiles for new foundation work.

Altogether, 17,855 individual steel components, representing 205 tonnes of fabricated steelwork, were used on the project, with most components installed via helicopter.

AGL Lakeside Pavilion at the Australian Botanic Garden in regional NSW, submitted by Hunter Galvanizing, won the Buildings – Small Project category. Made almost entirely of steel, it draws together a semi-permanent theatrical marquee and more permanent utility shed.

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The main steel was fabricated off-site entirely, and assembled with bolted connections to avoid onsite welding and maximise the speed of construction. Steel sections also featured a modular design for ease of transport to ensure fit within galvanising bath size capability.

Topping the Steel Clad Structures category was IGLU Central Student Accommodation by Bates Smart, Grindley Construction and Taylor Thomson Whitting in Sydney’ CBD. Weathering steel panels were applied to the striking façade, affixed with simple self-tapping connections to speed construction.

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A characteristic ochre brown patina not only complements the surrounding brick facades, but also produces a natural oxide layer to slow and eventually stabilise corrosion. A perforated metal layer was added to several areas to add detail, scale and texture to the building whilst serving as a privacy screen enabling natural light to filter into the space.

The Steel Excellence Awards are organised every two years, and seek to recognise the project teams associated with winning entries. Winners and finalists were shortlisted from the five state programs conducted earlier in the year.

Categories: Uncategorized

Six (6) Reasons Why Steel is Better

1. Convenience:  It’s lighter than wood and takes up half the space of lumber.

2. Ease of installation: Steel framing is easier to handle because the studs weigh a third less than wood and can be installed at 24 inches on center. They also are attached with screws, so moving studs is simple if you make a mistake.

3. Stability:  Wood is prone to twisting and warping; metal is not. Wood also wicks moisture, which can lead to mold growth and rot, while metal is immune. Metal does rust, so install a vapor barrier or sill gasket between the bottom plate and the concrete floor.

4. Strength: The strength and ductility of structural cold-formed steel (CFS) framing, along with the holding power of CFS connections, make it ideal for construction in high-wind and seismic zones such as the Philippine coastal areas.

5. Insect-Proof and Fire Retardant: Carpenter ants and termites can severely damage wood construction, but steer clear of metal. Likewise, wood burns and metal does not. A wall built with metal studs is virtually fireproof.

6. Lower construction costs: There are some nuances to this area. Steel framing can cost three  to 15 percent more than wood studs, but metal studs offer cost advantages in other areas that can offset this price difference.  Unlike wood which might need to be replaced over time, steel does not shrink, split or warp. As a result, there are no nail pops or drywall cracks to fix after the structure is completed. Consistent quality means that scrap is drastically reduced (two percent for steel versus 20 percent for wood), which also reduces costs for hauling off and disposing of discarded material.

Categories: Uncategorized