If you’ve ever wondered what goes into building everything around you, you’ll know that metal is the answer. You might even be able to guess which metal but what about the details of each of these metals? When it comes to the nitty-gritty of these metals and which kind of iron, steel or alloy goes into which product, most of the people are clueless.
About Foundries in India
Metal castings are produced in a foundry. Metals are melted into a liquid to cast them into different shapes and sizes. It is then poured into a mould and is removed from it once it starts to cool and solidify. The most common metals that are processed are aluminium and cast iron.
While we are well-versed with the role of iron in the industrial sector, what’s often confusing is the different types of iron and iron alloys – cast iron, ductile iron, and wrought iron to begin with. It all begins with a metallurgist listing down his requirements – mostly mechanical, and then an alloy is suggested. Followed by the above comes the choice of finalising a certain type of cast iron in the nearest casting foundry.
‘Cast iron, the term is used for the iron alloys cast in any foundry, and ‘ductile-iron is one such alloy. Let’s find out what types of iron are cast in a foundry?
White Cast Iron: Known for its hardness and abrasion resistance, this alloy cools quicker than other cast irons. It’s often used in bearings and other high-friction applications.
Ductile Cast Iron: An alloy of iron developed in 1948, ductile cast iron is a very important alloy for ferrous foundries. Being much less brittle than other cast irons makes this one of the most preferred alloys in cast iron manufacturing.
Malleable Cast Iron: This alloy is the predecessor of ductile iron, famously used and produced in any cast iron foundry. It is a white cast iron that is heat-treated for a very long period. It is used for small, thin castings under controlled heat conditions as it is a lot less brittle.
Gray Cast Iron: The standard form of “cast iron” is the great cast iron. It has a graphitic microstructure giving it an excellent vibration damping capacity and great machinability. Things that are made from grey cast iron. White and grey cast irons are extremely similar castings. What sets them apart is their colouring, which is only evident when it fractures.
Mechanical Properties Of Cast Iron
Based on the mechanical properties, the applications of each type of iron are decided. Different types of iron are suitable for different applications. Some of the important mechanical properties of cast iron include hardness, ductility, elasticity, malleability, tensile strength, and fatigue strength.
Cast iron is very beneficial for its ability to be moulded into different shapes. The affordable cost can also be added to the list of advantages. To make the cast iron usable in a wide variety of applications, it is often altered by changing the composition depending on the requirements of the casting foundry.
Casting Process Of Cast Iron Foundry
The process of casting is not as simple as it sounds. It includes many steps like making the patterns, melting the metal, pouring the molten metal, cooling it, removing it, cleaning all the parts, and then the final process of examination. The unadulterated cast iron alloy is brought to the cast iron foundry. Silica sand is used for making the moulds because of their capacity to withstand very high heat.
The iron is cast into different patterns in these moulds. Then, it is extracted and sanded to achieve a precise shape. Nowadays, a large number of castings are sent to milling centres for better finishing. A casting foundry may specialise in manufacturing only a special part like an automotive part or produce multiple parts. Some foundries specialise in making parts for the aerospace industries, and others make smaller-scale cast iron pieces.
Govind Steel Company Limited is a 55-year-old company that has continually grown to become one of the largest and leading foundries for Grey Iron Castings and Ductile Iron Castings in India, with an installed capacity of 24, 000 MT. If you have any questions about what we offer for customers or businesses, email us directly at email@example.com or simply visit our website www.govindsteel.com.
On the surface, the process of casting may come off as a simple task. It is just about pouring the liquid metal into a mould and set it. But over the years, the casting process has evolved into various types and intricate processes.
The first process of casting dates back to the 4th century in China. Since then, it has rolled into many innovations and development. In India, casting foundries flourished, providing the best iron products for commercial use.
A casting foundry follows the casting’s essential processes and decides its type based on the requirement and the scale of production. And we will discuss all of it here.
The Iron Casting Process
The iron casting process is carried out in a factory called cast iron foundry. The casting process is carried out in the following steps-
In the cast iron foundry, the primary metal or iron, internal scrap, external scrap, and alloying metal are melted in a furnace. The primary metal or virgin material is the one that is used to form an alloy. The furnace is heated above the melting point of the primary metal.
If the hydrogen concentration is higher in the mixture, it can increase the final product’s porosity. Higher porosity degrades the value of the product. Reducing the amount of hydrogen is called Degassing.
Generally, this is done by passing argon or nitrogen over the melt.
Moulding is usually done with a single-piece pattern or split pattern. The molten metal is poured into the moulds to get the desired shape of the final product. The patterns in the mould are made of wood, plastic, metal, or wax.
The construction of moulds depends on the type of molten metal, type of foundry, the casting size, the required quality of the final product.
4. Pouring And Degating
The molten iron is carefully poured into the mould by automatic machines or giant ladles. Once the metal solidifies, the runners, gates, risers, and heads are removed from the mould using cutting torches, bandsaw, and ceramic cutoff blades. This process is called degating.
The blasting process removes the unwanted debris that is still attached to the solidified material. Usually, this involves propelling tiny grinding balls over the material’s surface to remove unwanted debris like sand.
The tiny grinding balls are made up of glass beads, walnut shells, iron, aluminium oxides, steel, baking powder, etc.
Finally, the material is formed into the perfect dimensions by sanding or machining to even the rough edges. The product is now ready after clearing all the processes in the cast iron foundry.
Casting isn’t just of one type. Other types include sand casting, die casting, low-pressure casting, gravity die casting, centrifugal casting, vacuum die casting, continual casting lost foam casting, etc.
The casting foundry employs the type of casting according to the requirement of the final product. The processing time also varies according to the type of casting used.
We will assist you to know more about the cast iron foundry on http://www.govindsteel.com/.
Iron-carbon alloy tweaked by adding magnesium or cerium is what is commonly known as ductile cast iron. Ductile cast iron reacts with sulfur and oxygen while the iron is in the molten stage to create a more ductile alloy.
Cast iron is more of a brittle alloy as compared to ductile cast iron. Little addition of magnesium or cerium allows the ductile cast iron to have a stable alloy structure. The Resulting solidified castings have almost perfect nodules of graphite in it. Ductile cast iron is known for high resistance against impact and fatigue.
How Is The Ductile Cast Iron Made?
Similarly, like any cast iron, ductile cast iron gets its magic from being inside the furnace. The process revolves around incorporating more carbon into the molten iron. The iron in the molten state gets the magic potion of silicon, sulfur, manganese, and oxygen.
This oversimplification of the process might make it look easy but is not this simple in reality. The prime part of the process is adding carbon to iron as much as it can absorb. The composition mix gives the alloy the infamous spherical structure of graphite.
Ductile Iron Advantages
Ductile Iron Casting made out of ductile iron are significantly solid than regular grey iron or cast iron. Tensile strength of grey iron form stands between 20000-60000 psi. However, ductile cast iron can endure as much as double-cast iron’s highest psi strength.
Here are some more advantages –
- Ductile cast iron is a more potent form of cast iron. Unlike cast iron that can break easily, ductile cast iron can endure much more.
- Nodule formation in ductile cast iron promotes it to bend and not break, unlike the cast iron.
- Graphite structure of ductile cast iron works as a dry lubricant to have excellent wear resistance.
- Even after being harder to work with than cast iron, ductile cast iron dissipates and dampens vibration, sound, and heat.
Ductile Cast Iron Uses And Application
The ductile cast iron can offer strength, and enhanced wear resistance makes it fit for various uses. Here are some items made from ductile cast iron:
- Pipe and its fittings
- Disc-brake Calipers
- Gear Boxes
- Hydrostatic Barrels
- Idler’s Arms
- Large Machinery
- Military works
- Piano Harps
- Spindle support
- Suspension parts
- Truck Axles
- Valves for high pressure
- Wheel Hubs
- Power Transmission Yokes
Difference Between Regular Cast Iron And Ductile Cast Iron
Cast iron is easier and cheaper to cast, and strength is possible with heat treatment. Cast iron has a flakes structure of graphite. On the other hand, ductile cast iron offers higher strength and durability due to the graphite sphere structure.
Ductile iron has the upper hand at durability, given the spherical structure of graphite. Cast iron or grey iron is cheaper but lacks the wear resistance that improves the uses. The most popular type to be used for industrial purposes is the ductile form of cast iron. To know more about the best ductile iron casting manufacturers in India, you can follow http://www.govindsteel.com/.
Architecture has been continuously evolving for aeons. New and durable techniques have taken over the stereotyped styles. One of the techniques that are durable, efficient, and versatile is bar grating. An effective design of cross bars and bearing bars, bar grating is designed to withstand heavy loads with the least weight.
Metal grating manufacturers design bar gratings suited for trenches, stairs, decking, and flooring. In the following sections, we will study more about the types of metal bar grating and its noteworthy features.
Types Of Metal Bar Grating
The following types of metal gratings have one thing in common. They are perfect to lid the open sections in flooring, yet allowing light, air, heat, and sound to pass through it.
Aluminium Bar Grating
Versatility and durability define the aluminium bar grating. Moreover, it is lightweight, corrosion-resistant, and non-toxic. It can also be easily customised and recycled after use. There are many types of aluminium bar grating, like, riveted plank, flush top, rectangular box, and I-bar aluminium grating.
When bearing bars are intersected with the cross bars by deforming the metal, it is called swaging and is primarily used for aluminium bar grating. The intersection gives the bar gratings a long life to the structure.
Apart from swaging, another frequently used aluminium grating technique is press lock grating. Here the grating bars are arranged mechanically and locked by hydraulic pressing.
TiteWeld Bar Grating
If the spacing requirements are tight, then using the TiteWeld grating is a superior option. They provide maximum roll-ability. TiteWeld bar grating can be processed into circle cut-outs, toe plates, end bandings, stair treads, and radius cuts.
TiteWeld bar grating is perfect for applications involving bear bars arranged closely together. For high-heel traffic, the 7/16-inch on-centre bearing is considered safe.
Architectural Bar Grating
Among the many metal gratings, architectural bar grating is a suitable choice for sunshades, water fountains, railing infill panels, and sunshades constructions. It includes the usability of standard bar grating with an additional feature of aesthetic appearance.
It is typically used in ornamental grilles, building facades, walkways, sunshades, and fencings. In places like petroleum refineries, chemical processing plants, food processing plants, architectural bar grating is used in appealing industrial floorings and decks.
It is cost-effective, durable, and easy to install. It is frequently used in screening applications because of its permeability to air, liquid, heat, and light.
Picking the correct type of grating is essential for its applications as well as durability. Some good metal grating manufacturers like Govind Steel cater to such requirements to provide the best and durable metal bar gratings. To know more about their expertise, follow http://www.govindsteel.com/.
With the rise in metropolitans and smart cities, proper city planning remains the utmost concern. Significantly, the sewage management that runs below a city. Not just the cities, but the towns also need to have an impeccable sewage management system.
One of the essential parts of this sewage management system is the surface box covers. Surface box covers are installed on the surfaces or roads so that it easy to repair or inspect the subsurface utilities.
Let us through some light on the surface box covers, manufacturing process, materials, and quality checks.
Materials Used In Surface Box Covers
Surface box covers in India are usually made up of cast iron. Ductile cast iron is used for its enhanced strength and durability. Ductile cast iron contains manganese that helps to form nodules in the carbon present in the cast iron. Generally, this makes it more robust and malleable.
Gray cast iron is also used for surface box covers. It consists of the element iron and an alloy of silicon and carbon.
The other materials used to manufacture surface box covers are silica sand, clay, coal, and water.
Methods of Production
Surface box covers in India are manufactured in large foundries. The scrap steel that comes into the foundry is melted and alloyed to form an iron casting. The casting process usually consists of the following steps-
Aluminium patterns are designed for the top of the surface box covers. It is also carved out of wood, but considering the mass production in large factories, aluminium is considered the most viable option.
To form the surface box cover, scrap steel is melted in a furnace with a temperature of around 1500⁰C. Now the alloy metals are added to the moulting metal to increase its strength. Flux is also added to remove the impurities from the molten iron.
Sand moulds are created for the upper and lower part of the surface box. Green sand is used for the moulds. Both the moulds are tightly packed, and molten iron is poured through the vent. The vent also allows the gases to pass through the vent.
It takes about a day for a surface box to cool down completely. It cools down sufficiently in 60-90 minutes to be removed from the mould. It is then cleaned with a wire brush to present a complete look.
Quality Control For Surface Box Covers
Raw materials like scrap iron are not controlled. But the molten metal undergoes quality checks to analyse and confirm the appropriate quantities of alloys and flux. Strength and ductility are also measured using a tensiometer.
Also, the manufacturing process emits gases like carbon monoxide, sulfur dioxide, and hydrogen sulfide. The quality control team checks the permissible limits of these gases to avoid any health or safety hazards.
Next time you walk across a street and see a surface box cover, you know how it’s made and what purpose it serves.
The quality of surface box covers differs from manufacturer to manufacturer. If you wish to know more about the quality, manufacturing, and purchase of surface box covers, we recommend you to visit http://www.govindsteel.com/.
If your project lies around commercial and public spaces, choosing the correct type of drainage channel is essential to work for you. The wrong choice won’t only result in affecting the reputation of your company but also might put everyday people in dangerous situations. Before picking a specific type of drainage channel, you should consider a few factors like loading capacity, material, the purpose it will be used for, etc.
To help you out, here are different types of on-surface, drainage channels you can use for your project, majorly based on their loading ratings. Select the most appropriate type after which you can buy your product from a well-known heavy-duty drainage channel manufacturer in India for best results.
The drainage channels with B125 load ratings are the most suitable ones for domestic driveways. They can easily sustain the weight of family cars and vans. These channel gratings are made up of galvanised steel and are capable of withstanding light and average cars.
For Domestic Projects
For light-duty drainage works like in gardens, pedestrian areas, patios, etc., choose a drainage channel with an A15 loading rating. The material typically used in such type is polypropylene plastic or galvanised steel. Such channels are only suitable for the areas mentioned above as they can’t hold a heavier load.
For Car Parks
For car parks, a channel rated C250 is the best choice for you. If the area is way too commercial, you might as well go for one level up. Such a drainage channel is only suitable for light traffic and private use as it can’t bear a load of more than 25 tonnes.
For Major Roads And Highways
The major road needs a drainage channel that can take up to 30-40 tonnes of load. D400 is the best type of channel for such heavy traffic public areas. This type of channel can also be used for public car parks.
To stand the weight of a moving aircraft, you need the toughest and most heavy-duty drainage channel. F900 rated channels are the only suitable channel for this purpose. They come in ductile iron material with a concrete channel reinforced with fibre. They can withstand weight up to 90 tonnes and are extremely heavy-duty drainage channels.
To save assets and properties from damages inflicted by water, installing drainage channels is very necessary. With an ample of variables present in the market today, the process of choosing the right type could be cumbersome.
For more details, visit the website that provides you with the ideal material and help you out in the right direction. Contact only well-reputed heavy-duty drainage channel manufacturers in India for durable and quality products so that the results are satisfactory.
While working with iron, most people come across two kinds – ductile iron and cast iron. Cast iron has a chemical composition such that after solidification, a large part of its carbon is distributed through the casting as free or graphic carbon in the form of flakes. In case of ductile iron, it is a specially prepared iron treated in the molten condition with small doses of magnesium, cerium and other agents that will cause a large portion of the carbon to occur as spheroidal type of graphite form.
Ductile gratings are always considered the more superior form of iron, especially for construction work owing to its beneficial properties. Some of the advantages of using ductile gratings are:
High Compressive Strength: Compressive strength refers to the pressure that metal can take without changing its shape or form. Ductile iron has higher compressive strength, making ductile gratings ideal for the construction of manhole covers and other elements for the road.
Unbreakable & Durable: Considering that ductile iron is made with materials like magnesium, carbon, phosphorus, silicon and many more such elements, it adds to the strength of the iron, making it unbreakable The high strength also makes it more durable and gives it longer shelf life.
High Strength to Weight Ratio: Ductile iron has a high strength to weight ratio which makes it easier for manufacturers to manufacture lightweight castings, offering up to 50% savings on weight over grey iron castings and which leads to subsequent saving in the cost per piece.
Resistant to Corrosion: The mix of other elements into the iron for ductile gratings makes it resistant to corrosion which can occur in iron when it is exposed to air and water. Corrosion causes a great deal of damage and hence, it is advisable to use ductile iron, especially for manhole covers that are exposed to constant rain, sunlight, wind, etc.
Cost-effective & Less Maintenance: Compared to other metals, ductile iron is cost-effective and owing to its high strength and durability, it requires less maintenance. The chances of theft are also low due to its design, which is generally quite attractive.
For better performance and durability, it is essential to pick the right metal, especially in the construction and automobile industry. Ductile gratings can be a great choice for manufacturing in a cost-effective and safe manner. Govind Steel Company Ltd. is one of the leading and largest foundries in India with an installed capacity of 24,000 MT. Owned by the third generation of the family, Govind Steel has received a number of awards and continues to grow in Eastern India by producing quality grey iron castings and ductile iron castings. To know more, visit http://www.govindsteel.com.
The proper disposal of human waste has been solved by the sewage systems built across the various parts of our nation. And what keeps the sewage system separate from the actual city are the manhole covers. The history of the manhole covers is rather varied – what started as stone manholes covers are now made of cast iron.
How are Traditional Manhole Covers manufactured?
Most top manhole covers manufacturing is carried out cast iron foundries as the modern-day manholes are made out of cast iron. The process is fairly simple theoretically – the cast iron is melted and then poured, or cast, into a mold. In many cases, ductile cast iron is also preferred because of its greater strength and is generally found in and around airplane terminals. What adds more strength and durability to the manhole covers made of gray cast iron is the alloying element(s) – carbon and silicon. And in the case of ductile cast iron manhole covers, manganese is added to the molten iron that provides greater strength and malleability.
What are the Raw materials used besides Cast Iron?
Apart from iron, the other raw materials required in manhole cover manufacturing is green sand -which is sand bound together with clay. It is mainly used to produce the molds which are further used to store the molten iron. The sand mixture is about 90% silica sand, 4-10% clay, 2-10% organics and 2-5% water.
Design & shapes
All manhole covers are first structured in aluminum or wood as a model. This model serves as the key design and is used as a reference to make the mold and then the molten cast iron is poured. The intricate designs on the surface are often created by skilled artisans who personalize them. Coming to the shape of it, all manhole covers are round since it cannot go beyond its assigned diameter. Round manhole covers are convenient to move around as they can be rolled.
Assessment of the Quality
The key to controlling the quality of manhole covers is assessing the proper percentages of iron, carbon, and alloying metals. Once the casting is complete, the strength and ductility of the cast irons are tested to assure reliability. And lastly, the strength and ductility are determined by casting bar test specimens from the same metal used to cast the manhole covers.