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Foundries and Furnaces
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 bronze, brass, steel, magnesium, 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 furnaces, cupolas, reverberatory, 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!
Steel Cleverly Disguised as Wood
On the road between Tacloban City and Babatngon sits a beautiful farm by Rafael. Aside from the incredible landscaping inside and the good food to be had, we notice the attention to detail was impeccable. Probably no one except interior decorators and those in the steel business would have noticed the sturdy roof structure that can withstand the harsh winds and rain of Leyte.
If you look closely, you’ll see that the wooden roof structure is actually made up of steel trusses- c-purlins and angle bars painted to blend in aesthetically with the environment.
STRENGTH, BEAUTY & ENVIRONMENTAL SUSTAINABILITY, who could ask for anything more?
Did you Know?
Hollow block construction of homes is unsafe if there are no steel bars or wire mesh in between? This is why many houses in 3rd world countries collapse easily during an earthquake or even just a strong typhoon.
Using a steel wire mesh or a steel frame or simply dropping rebar rods into every other cell of the hollow block for reinforcement however means a much safer home, especially in earthquake prone Philippines.
Learn how to properly reinforce a hollow concrete block wall here.
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Moreover, steel is 100% recyclable, even if it is old and rusted and looks like junk already, it is still fully recyclable.
What’s more, the steel frame is not only strong enough to keep your walls from collapsing during thunderstorms, it also provides a path for the lightning to go straight to the ground should your house be struck.
Lastly, your living area can actually be much bigger since huge columns will no longer be necessary because a steel frame is strong enough for wide open spaces.
An Inventive Use of Angular Bars
A visit to a Bacolod furniture showroom recently yielded a nice surprise- angular bars adorned the walls both for form and function. Aesthetically pleasing, minimalist and unobtrusive, the angle bars were painted white against a white background and placed horizontally as a design feature on the wall.
Holes were then drilled into them so that different size picture frames and mirrors could be hung without having to drill into the walls.
Brilliant!
Save time and money with Steel
Pinoy Engineer Bow Moreno has succeeded in designing a building system that allows him to finish a 72-square-meter, 24 foot-high, two-story townhouse with a spacious attic in just 12 days and for less than P680,000. To prove it, his company, Bow Moreno Construction, delivered 10 townhouses in 120 days (exactly as promised) for the GMA-7 Employees Multipurpose Cooperative.
SO, HOW DID HE DO THIS?
In the article from the Philippine Daily Inquirer, Moreno explains how he has developed a system called “buil-to-order-web” or BOW building system which takes advantage of the versatility of the steel angle bar. He has put together a clever steel system that when built a certain way will have the strength equal to that of I-Beams but are lesser in cost.
VALUE ENGINEERING
Some methods the BOW system uses include 3 x 3-inch angular bars welded together and joined by round steel bars to form 3 x 6-inch channels that serve as columns and beams. These can then be easily assembled to form the skeletal frame of the house.
The concrete framework is then clad with MX panels consisting of corrugated Styrofoam boards sandwiched by an interconnected pair of galvanized wire mesh which are plastered with cement using pressurized bucket spray for strong & efficient bonding.
Moreno also explains how he does the flooring and roofing. You can read more about his method by reading the article here and start thinking of ways you can also save with steel.
NEDA teaches the use of Coconut Fiber, Angle Bars & C-Purlins for Roofs
In this article by NEDA, they show a 2-storey experimental house with a total floor area of 53 square meters constructed utilizing coconut fiber-cement boards (CFB) together with component steel as its structural framework.
Given the plentiful coconut tree- ubiquitous in fact on our Philippine shores, CFB as an alternative construction material for walling, ceiling, roofing and base support in upper level flooring of house makes complete sense. In fact, NEDA proposes its use in the fabrication of furniture (tables, chairs, desks, etc.), cabinets, boxes and vases inside the house.
Roofing System
MATERIALS USED: The house has an A-frame design with the roof system consisting of the traditional rafters and purlins construction. In the picture, the green roof cover is made of 8 mm thick, 75 cm wide, and 75 cm long CFB panels painted with waterproof paints.
The rafters consist of 0.6 cm X 5 cm x 5 cm angular steel bars and the purlins made of 0.60 cm x 3.8 cm x 75 cm channel bars. The components were assembled on site by welding the members together. The two opposite rafters were joined together end to end at the ridge beam (0.60 cm x 5 cm x 5 cm angular steel bar) while the other ends were directly connected to the base plate of the second level floor extending to the eaves or overhang of about one (1) meter.
Interestingly, the main roof structure was made to incline by about 40% greater than the normal slope of 35 degrees considering that the roof cover is made of experimental fiber-cement boards. This will ensure faster surface water run-off in case of downpour.
Of course, the question is, how strong and lasting is the coconut fiber? This project by NEDA aims to evaluate the performance of CFB in actual service condition. To find out more click here
Note: A coconut fiber-cement board (CFB) is a product manufactured from fibrous materials like coconut coir, fronds, spathes and shredded wood that are mixed with Portland cement at a predetermined ratio of 60-70% cement to 30-40% fiber by weight.
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21st Century Steel Mill, Inc. 