How is the Pure Aluminum Produced? (part 1)

Pure Aluminum

Aluminum is one of the most well-known materials existing on the planet. However, pure aluminum does not occur naturally, and a chain of processes is required to develop the usable material for different purposes. Many compounds are quickly produced due to the easy atom binding in this metal. Simultaneously, it is impossible to isolate the metal by simply melting the compounds in a forge, as in metals such as iron. The pure aluminum production process is very complex and requires special machines and vast amounts of electricity. Thus, smelters for this metal are always built in the vicinity of power energy sources, including hydroelectric power plants that do not contaminate the environment. Now let’s get to know the best practice methods and steps for producing pure aluminum material.

Bauxite Mining for Creating Pure Aluminum

Pure aluminum production is essentially broken down into three main stages. The first step is extracting the bauxite, which contains aluminum from the ground. The second step is processing the bauxite into alumina or aluminum oxide. Finally, the third stage produces pure aluminum by using an electrolytic reduction in which the aluminum oxide should be broken down into its components by utilizing electric current. About 1 tone of pure metal is made from 4-5 tons of bauxite, producing 2 tons of alumina.

There are many different minerals available from which pure aluminum can be produced for other industrial materials, such as Aluminum composite panels. Bauxite is a raw material that is commonly used for this purpose. Bauxite generally contains 50% aluminum oxide mixed with some other substances.

Bauxite is available in different variations. It can structurally be dense, solid or crumbly. Usually, it has brick re, flaming red or brown color due to the existence of iron oxide. The bauxite can be grey or white in case of lower iron content. However, dark green, yellow, and even multi-colored bauxites with purple, bluish, black and red strains are available too.

The most practical way to mine minerals is by utilizing open-pit mines. Special equipment is used to cut one layer after another off the surface, including rocks, and then transported to factories for further processing. However, there are other areas where aluminum ore needs to be mined from deep underground layers, which require underground mines.

Alumina Production for Pure Aluminum

The next step in the pure aluminum production chain is obtaining aluminum oxide from bauxite, also known as a white powder. Bayer process is one the most common methods of producing alumina from the mineral. This method is discovered over a hundred years ago and is still a very a suitable system.

Bayer Process

About 90% of alumina producers utilize the Bayer method. This system’s only issue is that the Bayer process is efficient on high-quality bauxite with low admixtures, such as silicon. This method’s instruction is as follows: Dissolving the crystallized aluminum hydrate in concentrated caustic soda at high temperature. After the temperature is lowered and the solution’s concentration increases again, the material reduces but the other elements existing in the bauxite settle to the bottom appropriately.

After aluminum hydrate desolvation in the soda, the extra stuff can be isolated and removed quickly. The additional elements are also known as ballast or red mud. Large hydrate particles can be filtered out from the solution without requiring the complex procedure. For exceeding the water, manufacturers wash, dry and heat up the material. The result of the process is alumina. This substance has an unlimited shelf life. However, it has to be stored under appropriate conditions because it can absorb moisture at the first provided opportunity. Thus, alumina producers choose to ship the material to smelters ASAP. Manufacturing system stack the metal into piles that weight about 30,000 tones. As a result, a kind of layered pie about ten meters high is built. The mass is then cut and loaded into the railroad for dispatching to smelters to create the material suitable for producing aluminum sheets and other products such as aluminium sidings for cladding.

Sintering Process

Sintering is another method for alumina production, which is less common in comparison to the Bayer system. The technique is about making solid materials from powders at high temperature. The primary element is sintered with lime and soda. The latter two parts generally bind the silica into inexplicable silicates that can then be easily separated from the produced alumina. This method is suitable for obtaining alumina from a high content of toxic silica admixture bauxite. However, sintering can consume more energy in comparison to the Bayer process.

Cryolite

Alumina is considered the direct source of material in the pure aluminum production procedure. However, Cryolite is another component that is necessary to create the right environment for electrolysis. This substance is a rare natural fluoride mineral that is manufactured in artificial ways due to its scarcity. In modern industries, Cryolite is made by mixing up hydrofluoric acid with soda and aluminum hydroxide.

In part two of How is the Pure Aluminum Produced, more details are about the production procedure is introduced.

Things to Know about Aluminum Composite Panels Installation

Aluminum Composite Panels Installing Methods

Aluminum Composite Panels are popular external cladding products that are widely used in modern architecture and buildings. They are also used as the internal surface designing and coating material. To ensure that these products fit correctly into the design of the construction, they need to be fabricated precisely and then installed in various methods. Almost all of the methods utilized in the industry for this purpose are approvable. Before installing ACM panels, some prior action needs to be taken, considering thermal contraction and extraction, removing the protective film, and defining the process direction.

Thermal Contraction and Expansion

Change of temperature can lead the ACP fasteners into intolerable overstressing and bowing. Thus, to avoid this type of damage, heating the construction work and ambient air process must be considered. It is essential to know that aluminum composite panel has a coating system, damaged if the temperature exceeds 100-centigrade degrees. This means that the thermal resistance of the material must be modified before installation.

Removing Protective Film

Generally, aluminum composite panels’ manufacturing company leaves a non-transparent protective film for covering the material before leaving the product line. Humid ad hot weather conditions can make the film’s residual glue stick onto the lacquered surface of the ACP. Thus, removing the protective film as soon as the material reaches the construction site is necessary. After the removal, it is essential not to use a marker pen or tape on the coated surface. Particles such as acrylic, rubber, and epoxy can be very harmful to coating integrity.

Aluminum Composite Panels Process Direction

It is crucial to install the ACP materials in the predefined direction, whether horizontal or vertical. Manufacturers apply the paint finish in one consistent order. Thus, for maintaining the finish and the color across the panels, each ACM panel must course in the correct direction. Identifying the path is not so hard. The protective films are being developed, having an arrow on them, which defines the proper installing order and the applied finish. Builders need to install all the panels in the same direction throughout a construction project.

Aluminum Composite Panels Installation Methods

After the preliminary preparation steps, it is time for the installation process, which can be done utilizing many methods. Here are some of the most common ACP installation methods in the industry.

Hanging Method for ACP

One of the most common ACP installation methods is the hanging method. This installing system can simplify the procedure, and as a result, it shortens the construction period. In this system, panels are not fastened tightly to the mainframe and are suspended. Thus it is easy to loosen the movement of thermal expansion and contraction. The hanging installation system must follow the steps below.

  • The design of the facing is defined relative to the axis of the construction. The ACM panel skeleton consists of vertical and horizontal pieces. The vertical rod should be fixed, followed by the anchor point determination of the vertical frame.
  • Then installing the fixed connection part of the basis of the pay-off line is required, followed by an electric welding fixture. Thus, the connection partition is welded to the embedded domain.
  • The welding frame is utilized to take the main skeleton on it. This step of installation includes checking the elevation and center lining the position. Additionally, the cross-section weld should be treated as anti-rust paint. Then the quantity, height, and depth of the insertion will be set.
  • The last step is to install the Aluminum panel on the inner frame of the profile using the screw holes and fixing them to the steel frame block with particular supplies such as rivets. The boards need to have 10-15 mm of a gap and be injected with silicone-based material for sealing purposes.

Wet Sealant Joint

Another renovation and modern method for aluminum composite panels is using wet sealant joints. This method includes applying appropriate sealing material to the joints to ensure water-tightness and prevent water infiltration into the building structure. Followings are the six steps that need to be followed in a wet sealant joint installing system.

  • Choosing an hourglass-shaped sealant is essential, and the width should be twice the depth of the gap.
  • The backer rod diameter is generally 25% larger than the central joint, which needs to be filled.
  • Joint sizes are typically designed to be four times greater than the expected movement.  
  • The sealant is not made of caulk, and it should never be tooled with a finger. Choosing the right tool is always a priority.
  • Then, preparation for sublayers is necessary.
  • Applying wet sealants under average temperature is recommended. This is due to the expanding and contracting characteristic of the joints.

Dry Gasket Joint used in Aluminum Composite Panels

There is another installing method for ACP materials instead of wet sealant joints, including dry gasket joints. This method is durable and can reduce the amount of strain and dirt on the panel’s surface. The process will be completed by doing the following 11 steps.

  • Inspecting the gasket to ensure the absence of defects and checking if it has clean cuts with no rips or tears is essential.
  • The gasket should be placed between the panels with precision.
  • Avoiding applying to release joint compounds on the surface of the gasket is needed.
  • It is familiar to insert 2-3 bolts through connecting panels to reduce the damages and pinches.
  • Load bearings need to be coated with lubricants considering many factors such as particle types, sizes, and temperature.
  • Consulting with the gasket manufacturers is vital in defining the torque values that need to be applied to the nuts.
  • The most efficient way to tighten nuts is by utilizing a cross-bolt pattern and multiple tightening rounds during the ACP installation procedure.
  • The nuts need to be tightened by hand but generally with 20 percent lower torque than the recommended amount.
  • Each nut will be torqued 30 percent of the predefined torque amount.
  • The last step needs to be repeated by applying 40% torque until 100% of the maximum torque is approached.
  • Finally, involving at least one final maximum torque to all nuts is needed to place all nuts in a uniform torque.

How Long Will Aluminum Sidings Last?

Aluminum Sidings

Aluminum Sidings are products, which are designed specifically for protecting the construction from external factors. They can take the loads and damaging issues away, whether caused by wind or due to the sun and rain exposure. Depending on the construction’s location and other vital factors, aluminum siding can be the right choice for facades cladding materials. Just like many industrial products, aluminum sidings come with many advantages. The material is considered soft, and the thickness can make a tremendous difference. It is varied from the cheapest one, developed in 0.4 inches in thickness, to the most expensive materials with the 53-gauge characteristic. One of these products’ most essential factors is that they are produced in both horizontal and vertical formats, allowing the designer to create unique aesthetic exteriors and have limitless freedom in breathing life into their ideas. Aluminum sidings are also very popular for their insulation properties. They can save a considerable amount of heating and cooling energy cost over their long life span. Additionally, this type of siding is very lightweight and has an easy installation and fabrication procedure. Thus, the labor cost is lower in projects that are created from aluminum materials.

Aluminum sidings are the perfect choice for people who choose to live in coastal communities with lots of humidity, moisture, or even salt spray in the air. Other sidings such as wood can absorb the water and cause different types of issues for the homeowners, and they have a smaller life span than aluminum. This type of siding is entirely recyclable and insect-proof. However, they are many challenges when choosing a siding for any commercial or residential building. The most common challenge is deciding whether spending lots of money on the material that requires heavy maintenance or buying an inexpensive material that will need to be repaired over time is logical. The other factor, which is essential when choosing the best siding for the construction, is the products’ life span.

Aluminum Siding’s Life Span

As told, aluminum siding is a recyclable and long-lasting material and requires minimal maintenance. Its lifetime can exceed 30 years, and in some cases, it can provide 50 years of perfect service for architectural applications. It will work without any problems for up to 15 years. However, after that, it can start to show its age by flaking off and getting chalky. It contains a glaze of paint that is generally baked onto the material and creates a robust coating system. This coat is not eternal, but the good thing about the finish is that it can be repainted after proper preparations. The down part of the painted aluminum sidings is that they can be dented or scratched, making them not ideal for high traffic areas. The surface can become pitted and damaged. However, some of the imperfections can be repaired easily. In the case of replacement, it can be challenging to match the new product’s colour with the sidings that already exist. This is due to the presence of the shaded colors in old products. This issue can be solved by removing the less visible siding piece and put a new product in its place.

Factors that Will Affect the Lifetime of the Aluminum Sidings

Many factors will affect the life span of the aluminum sidings. Knowing them can help the homeowner improve the siding’s long-lasting characteristic, which is used in the building’s structure. The followings are the critical factors to know that will change the lifetime of the aluminum siding.

Thickness of Aluminum Sidings

Comparing siding panels by their thickness can help choose the approvable material for the building. This property of the product is also known as gauge or grade, and it can be the key to determining how long the aluminum siding will continue doing its job. The most common thickness is about 40mm, and the thickest one is 50mm. Low-grade sidings will crack and sag in a decade, and it will fade much sooner. On the other hand, heavy-gauge sidings are considered more durable and fade-resistant. Thicker products are better looking and often come with more extended warranties.

Aluminum Siding Maintenance

Due to the aluminum siding’s duty to protect the building from rain, wind, heat, cold, dust, etc., its life span depends on upkeep. It is correct that aluminum material does not require complicated cleaning and maintaining process. However, taking care of the material once in a few years can increase the product’s lifetime. They can be easily washed. It is essential to check them annually for cracks, moisture infiltration, and damages as they can speed up the deterioration and lead to costly repairing procedures.  

Other

One of the benefits of aluminum sidings is their flexibility. They can take winds with a high amount of force that would deform any metal siding yet never show a mark. They can also contract and expand with temperature changes, and they are installed with different supplies that provide an accurate gap between the sidings for ensuing the movement. However, extreme temperature changes may cause aluminum sidings to become more brittle or warp over time. Some high-speed winds that carry stones or hailstones can break the old products. Thus, selecting a product with a warranty of 150 mph winds is recommended for all types of buildings.

Is Aluminum Siding Good for a House?

Aluminum Siding

Aluminum siding is one of the most common forms of sidings and is generally used as an exterior cladding material. Modern aluminum siding is made from aluminum coil stock, which is coated with chemical substances to protect the base metal and then painted for protection increment and aesthetic purposes. These products need to be baked for durability and this often involves adding glaze for creating unique textures.

A Brief History of Aluminum Siding Manufacturing

Aluminum siding creation goes back to the 1920s and one of the earliest architectural purposes of this material was to develop ornamental spandrel panels for huge commercial buildings. As time went on, architects start to utilize these sidings for residential structures. By the 1940s, these cladding materials quickly became very popular due to the advantages and benefits they provided. They dominated almost all of the cladding materials in use at the time. The first housing project which took place in 1947 and the aluminum siding was its cladding product, was a Pennsylvania subdivision.

Aluminum siding remained very trendy and popular until 1970 when the energy crisis occurred. At that time, producing this type of cladding required a great deal of energy and a huge amount of raw materials. These factors affected the usage of aluminum siding in a negative way. However, along with technology growth, the manufacturing system of this type of siding has also improved. Thus, it gained its position among the other practical exterior sidings over time.

Why Choosing Aluminum as a Siding Material

Aluminum is one of the most common materials on our planet and it is considered to have easier extraction procedures in comparison to other metal elements. Aluminum is an insect-proof, dent-resistant material, in addition, it is not flammable thus it can be a secure substance for the building construction process. Metal panels that are created with modern technologies often do not require frequent maintenance and an irregular simple washing process is all they need.

Aluminum metal is a soft element, which means the thickness of the produced siding can make an extreme difference for the cladding. The standard thickness gauge for this type of siding is 44 and the best products, which are more expensive than the regular ones, are developed in the gauge of 53. However, they are cheaper products available in the market that have 0.4 inches or 40-gauge thicknesses.

They are different paint finishes for aluminum sidings that are applied in a variety of colors at the factory. Customers can order the type of long-lasting finishes equivalent to their taste and needs. Most of these colors offer 15 to 25 years of service without fading or chalking. The product can last more than 50 years if it is maintained properly and kept clean with the minimum amount of impact. Aluminum can be molded and stamped with other common patterns such as wood grain. Many architects and designers often create exterior designs that are a combination of aluminum siding and other materials such as stone, glass, and masonry to provide a unique and aesthetic appearance.

It is essential to have in mind that there are other modern metal cladding systems that are way better than aluminum siding which are called ACM panels or aluminum composite materials.

Advantages of Aluminum Sidings for Houses

There are many factors to consider when it comes to choosing the best type of siding for renovation or new construction projects. The most common factors include durability, price, standards, sound insulation, maintenance, etc. Depending on the location of the facility, aluminum can bring many advantages to it. Followings are some of the most important advantages of Aluminum sidings that can be beneficial for company owners or homeowners.

Durability

One of the most important factors for designing any product for a facility is its durability. A durable aluminum siding can last for more than 40 years. Most of these products are manufactured from coil stock materials, which are generally created from old recycled products. Aluminum sidings are coated with chemicals to increase their corrosion-resistant characteristics. The final color is baked on the top layer while having different textures that customers choose. These products do not crack with age and are considered sturdy.

Design Flexibility

Unlike other siding materials, aluminum comes with a number of different textures and patterns such as wood patterns, which allows architects to develop unique looks for the buildings. Many people think that sidings only come in horizontal planks. However, aluminum sidings are available in both vertical and horizontal panels. This also increases the flexibility of the design for different purposes.

Cost-Effective

Sidings that are made from aluminum are considered the cheapest products available for exterior cladding. It is generally 80% cheaper than other types of sidings. The installation process is also very simple, thus, it will help the homeowner on saving money on the cost of labor.

Low Maintenance

The only cleaning procedure the aluminum siding needs is simple water rinsing once a year. This is done to make sure there is no debris stuck in windowsills or seams. Repainting the product is only needed when it becomes faded.

Insulation and Energy Efficiency

Aluminum sidings are considered energy-saving claddings for heat and are also perfect for sound insulation purposes. Products that are created in heavier gauges will work better in comparison to thin ones.

Recyclability and Environmentally Friendly

This type of siding is a GREEN product, which means it is 100% recyclable thus it will never need to go to landfills.

Water Proof and Corrosion Resistant

Aluminum is a perfect material for those who want to build their homes in coastal areas with high humidity levels. The product does not absorb humidity and it is expected not to rust. Even if there is a small amount of humidity in the product, it will dry out in the heat.

Insect-Proof

Aluminum does not contain any natural and organic material in its structure. This specification makes the product immune to rot and insects. This ability has made this type of siding the most popular choice in areas with a high level of termite presence.

Fire-Resistant

This type of siding has the ability of not being melted or burnt and due to its non-flammable ability, it is preferable for areas that have frequent brush fires.

How to Make Aluminum Composite Panel?

Aluminum Composite Panel

Aluminum Composite Panels, which are also called ACP materials or ACM panels, are popular construction products that are widely used in modern building architecture. These panels are not just a reverberation for interior or exterior designers and architects but also are beneficial for the environment. They are considered new sustainable materials known as sandwich sheets and brought new fields to the architecture. This means the composite panels do not just increase the durability of modern buildings but also contribute making the whole world sustainable and cleaner. Thus, using them has been expanded in the last few years to cover up energy efficiency and low price possibilities. Additionally, they are specially created for the ventilated facades rehabilitation and renovation.

Obtaining Aluminum from Nature

Aluminum is one of the most common elements found in the mother earth’s crust. However, the pure material that is used for developing different industrial products such as ACP does not occur naturally. Thus, there is a standard process defined for obtaining the usable material. This process is broken down into three main stages, which are extracting bauxite, turning them into alumina, and then producing pure material using electrolytic reduction. Bauxite, which is found naturally on the surface of the ground, contain aluminum in their structure and is made up of aluminum oxide mixed with other elements and minerals. Experts extract this material by using open-pit mines. For turning the material into alumina, a common process, which is called Bayer, is utilized. The produced alumina has an unlimited shelf life.

However, it should be stored under precise conditions due to its property of absorbing moisture. After this process, for creating the pure material, another component is required for creating the best environment for electrolysis, which is called Cryolite. In modern manufacturing systems, it is made by mixing up aluminum hydroxide, soda, and hydrofluoric acid. The last stage of producing pure aluminum is the electrolytic reduction, which requires an area for smelting the material. This area consists of many large rectangular constructions, which have a length that exceeds one kilometer. Inside these buildings, there are hundreds of pots or cells arranged in rows, which are connected to power sources through massive cables. In each of these cells, pure aluminum is being developed from alumina. The material is extracted from the cell by using a special vacuuming bucket for two to four times per day. A hole needs to be created in the cryolite and then the liquid aluminum is sucked into the bucket through a pipe connection. After obtaining the pure metal, manufacturers start producing ACM panels and aluminum composite materials.

Production of Aluminum Composite Panels (ACM Panels)

ACM panels or Aluminum composite panels can be produced in different methods and ways. The production procedure can be divided into two methods of cold composite and thermal composite. These two can additionally be classified with continuous and intermittent methods. ACM panels are generally manufactured by joining thin aluminum skins to both sides of a lightweight core, which is typically thermoplastic.

The production process of aluminum composite panels starts with cleaning the coil material. This material, during its creation, due to the needs of the process, is coated with anti-oxides and lubricants, thus a speck of considerable dirt and dust will be attached to the material during transportation. This can affect its adhesion thus precise cleaning is required. After coil cleaning and chemical treatments, a dense protective film starts to form on the surface of the material. This coat can improve the oxidation resistance of the panels and will increase the lifetime of the paint finish.

The produced aluminum composite panels of exterior composite sheets are coated with two layers of primer and paint. The top layer of the cladding materials is an extreme weather-resistant fluorocarbon, which has, resin substance and called polyvinylidene fluoride. This coat keeps the surface of the product protected due to its ideal UV resistance and environmental pollution characteristics. In addition, the surface can have beautiful marble color and pattern, which makes it perfect for creating modern architectural designs. The fluorocarbon substances are usually applied to the coils by roll process and then baked at lofty temperatures for drying. The last layer of coating is a varnish surface and this creates a total thickness of 30 micrometers. Each of these layers must be baked and dried at 200 degrees of Celsius for almost 60 seconds. After the drying process, the heating oven must be cooled by an air cooler. The interior wall paint is generally made of polyester, epoxy resin, or acrylic. It is important to have precision during installation and transportation for preventing any further damages on the product such as surface scratches.

The protective film, which is a self-adhesive material, needs to be removed from aluminum composite panels after the installation procedure. Then, the aluminum coil, which is coated with fluorocarbon resin, can be compounded with the core material. This material is also a three-layered substance that contains adhesive on both sides and PE plastic in the middle section. In the case of Alpolic materials, the core portion can be either a proprietary mineral-filled, fire-resistant, or polyethylene material. In both cases, the standard layers will be produced in 0.5mm thickness. Some Heavy-duty skins that have 0.8 thicknesses are also available on the market. The completed ACM panels and ACP material are available in 3mm, 4mm, and 6mm thickness that the last one is the most used thickness for the building industry. However, there are some custom sizes available for special demands.