The Production Process of Investment Casting Foundry

Investment casting manufacturing is one of the most profitable manufacturing processes in this day and age. Investment casting foundry claims that the manufacturing of steel for several uses in almost all aspect of life is one of the oldest metal working processes in the world.

This manufacturing process has not changed at all for over a hundred years and the industry is still growing at a rapid pace.

This process of metal working dates back to five thousand years ago. It was used to produce bronze and copper for pots, vessels, weapons and tools, gold jewelry and statues for decoration and personal use. This process was created by ancient civilizations of Mesopotamia, Egypt along with the Han Dynasty of China and the Aztecs.

There were several processes involved in the investment casting, such as:

·         The lost wax casting was done with the use of bees wax for making a particular pattern while it was in liquid form.

·         The wax was allowed to harden over time, away from the sun to get the best shape for the final casting.

·         After the wax was hardened it was dipped in molten metal to have the final shape.

The earliest process recorded goes back to 1100 AD which speaks of a sculptor named Benvenuto Cellini molding a statue after the Greek Hero Perseus holding the head of Medusa.

Despite the process being old, it requires high tech advanced metal forming techniques that are bound to produce a higher quality and quality of steel and stainless steel parts. Investment casting is a one on one process that creates one wax per metal part.

Because it is flexible and ever changing there it can develop a lot of complexities that need to be solved in order for it to run smoothly. With the correct casting methods however a large amount of metal works can be produced in a short time.

In this day and age with technological evolution, we have managed to create superior machines that make the process of aluminum investment casting easier, reliable and really effective with features such as quality control equipment, computerized processes, waxes, and refractory materials.

Modern day steel casting is used for several benefits, such as the fast and reliable creation of metal parts and metal components that cannot be produced with the use of the normal manufacturing processes.

A good example of using this type of casting is the creation of planes that carry several passengers but need to be as lightweight as possible. These large stainless steel parts cannot be processed by regular methods and therefore investment casting is highly preferred for its precision and easy execution of the metal working process/

Apart from this, metal investment casting can be used to manufacture components such as sand casting, forgings and welded fabrication castings. Investment casting is popular because it is known to reduce the cost while improving the quality.

Investment casting foundry and other companies rely on investment casting techniques for creation of items such as turbine blades, airplane parts and even aerospace parts. It is clear that this casting technique is indispensable in the steel industry.

Need To Know About Pressure Relief Butterfly Valve Castings

Pressure relief butterfly valves are flow controlling devices which isolate or regulate the flow of any fluid. Its closing mechanism is a rotating disk, unlike the ball valve. With its expanding usage throughout different industries, butterfly valve castings are very high in demand, globally. So, let’s take a quick look at the basics of these valves to understand their relevance.

How does it operate?

The basic principle of operation is identical to that of a ball valve, which allows for a quick shut off of flow. But usually people are more biased towards the former because of their comparatively lower cost than the latter. In addition, butterfly valves are lighter in weight, hence requiring much less support. A butterfly valve’s basic functioning design is:

• A disc is placed at the centre of a pipe.

• A rod passes through that disc to an actuator placed outside of the valve.

• By rotating the actuator, the disc can be turned parallel or perpendicular to the flow.

• Unlike the ball valve, due to the constant presence of the disc within the flow, there is a pressure drop induced even when open.

The butterfly valve belongs to the group of quarter-turn valves. While operating, the valve completely opens or closes with the rotation of a quarter turn of the disc. The “butterfly” comprises nothing but a disc made of metal, which is placed on a rod. The disc is twisted at the time the when the valve remains closed and this ends up blocking out the passageway, whereas, when completely open, the disc on the valve gets a quarter turn rotation, to allow the fluid flow in an unhindered manner. The valve can be opened in a gradual increasing method, to enable throttle of the flow.

Different Kinds of Butterfly Valves

There are different kinds of butterfly valves available to suit different pressures and usages. The most common kinds are-

• Wafer-style butterfly valve: This type of butterfly valve has a designed to keep up a blockage against pressure gap that is bi-directional, to stop it from flowing back in systems that are meant to have unidirectional flow.

• Lug-style butterfly valve: In these types of valves, both ends of the body have threaded inclusions which enable installation of the valves into a system that has just two bolt sets, without any nuts. This setup allows either sides of the piping arrangement to be disconnected without affecting the other side.

• Rotary Valve: These kinds of valves comprise a variation of the basic butterfly valve where pockets are included in the butterfly as an alternative to being flat.

Usage of Butterfly Valves in Industries

• Butterfly valves are frequently used in the chemical, pharmaceutical as well as the food industry.

• These valves are also used by firefighters on their hoses to limit their pressure.

• These are also abundantly used on front and rear suction ports, tanks and water pumps.

• In case of specific valves, it is possible that the valve may perform additional functions; e.g.-cast iron butterfly valves not only act as a regulatory device but can actually stop and start the flow as desired.

Due to its low cost, high functioning and simplicity of installation, butterfly valves have been replacing ball valves in their several usages (like the petroleum industry). But it is important to make sure that the valves used in these industries are manufactured according to the CGMP (Current Good Manufacturing Practice) guidelines. In different industries, butterfly valve castings are preferred and appreciated alike, by virtue of their efficiency and simplistic design.

A Comparison Between Butterfly Valve and Ball Valve Castings

The butterfly valve and the ball valve are the two most commonly used valves in the industrial sector. The two have many similarities and dissimilarities. While they look very different from each other, both of them tend to perform very similar functions. This article about ball valve castings and more will bring to you a comparative study of the ball valves and butterfly valves.

The similarities:

·         Both of them are essentially made by combining a variety of different metals like stainless steel, brass and cast iron.

·         Both of them are very commonly used because of their high durability and shelf life.

·         Both of them are also economical, which makes them always be high on demand.

·         Both of them can be used at different temperatures for the regulation of flow of a variety of gases and liquids.

The differences:

·         The construction and look of the two valves are vastly different. The ball valve castings have balls with holes through them. The butterfly valves on the other hand have disks mounted on rotating shafts.

·         The working procedures of the two are also different. The ball valve opens, blocks or partially opens a hole in the ball to control and regulate the flow. The disk is what the butterfly valves use. The handle is used in the latter case to turn the disk by ninety degrees to either let the flow completely through or to completely block it.

·         The pressure drops involved with the two valves are different in nature. In the ball valves, there is hardly any difference in pressure and that is a huge advantage. The ball valve will turn no matter how much pressure is being exerted from the end of the supply unit. However, the same is not true for butterfly valves. In this case, with the interfering nature of the disk, there is always a drop in the pressure. This can go on to have serious problems later on.

·         In the sector of uses, both have their own advantages and disadvantages. Ball valves are better overall but more expensive. They are most commonly used for the flow of gas. This is because they have a better sealing mechanism with very low chances of leakage.

On the other hand, butterfly valves are economical and boast of low maintenance. They are used for public services like municipal water projects and sewage control. Even projects that involve redirecting or controlling the flow of streams or rivers, butterfly valves are the chosen options.

A careful inspection of both must be done before you choose to use one for your necessity. Understanding the structure and function of both is necessary to pick the perfect valve for the function you need it to perform. Ball valve castings as well as butterfly valves are available widely and easy to procure. You should feel free to contact a trusted manufacturer who can explain and choose the best suited valve for you. Do your research well before investing as it always better to be safe than sorry. 

What is the Lost Wax Investment Casting Process?

The lost wax investment casting process refers to a procedure where casting of a replica sculpture can be done from a sculpture that is original. Known by a variety of names such as investment casting, precision casting and “cire perdue” (French), the oldest artifacts made from the lost-wax casting process date back to 4500-3500 BC in Israel. Other than that, artifacts have also been found in other parts of the world. Although the procedure has been modified according to recent times, and varies according to foundries, the traditional methods are still preferred and the steps are standardized.

1.     What’s the process behind lost-wax casting?

The casts are made from a copy of the original model, which could be made clay that is oil or wax-based. The moulds have outer and inner moulds, into which molten wax is poured to create an even coating over the inner surface. The outer mould is made from plastic or fiberglass, while the inner mould is made out of polyurethane rubber, latex, and silicone. Moulds mostly consist of two pieces along with a shim containing keys, which are required to reconstruct the original sculpt. After the poured-in wax cools down and hardens, the mould attains the preferred thickness.

The wax model is then removed from the mould, which may be used for making multiple models. A heat-resistant mixture is then poured into the mould to blend out any defects, and the shell is secured with many layers of the plaster. Other molded pieces are now attached to the main body. The model is inverted and baked in a kiln, which dries out the plaster and the leftover wax runs out.

After removing remnant moisture, the shell is then packed with sand and molten metal is poured into it. After it has cooled down, the shell and the core are removed which reveals the original casting. The metal is now “chased” to blend out flaws, and the casting now looks identical to the original model. The final casting is filed down and finishing touches are added as needed.

2.     What are the other uses of lost-wax casting process?

The lost-wax casting process has been used by foundry-men and artists to make intricate sculptures, ornaments and automobiles for centuries. Apart from this, the process is also popular for making casting jewelry, brooches, buckles and other small parts needed in various industries. Lost-wax casting can also be seen in textile use, where the wax and textiles are replaced by metal when casting. Due to fabric reinforcement, the model is thinner which reduces the amount of metal used in the mould. 

3.     What are the advantages of the lost-wax casting process?

Despite modern ways of casting, foundry-men and artists still prefer the traditional methods of casting. Some of the advantages include –

a)  The lost-wax casting process can be used on any material that can melt burn and evaporate to leave behind a mould cavity.

b)   The duplicate model will reproduce even minute details of the original sculpture.

c)     Allows for unique shapes of casting that would be impossible in other methods.

Therefore, the lost wax investment casting process is a seasoned method for the reproduction of various objects. However, the procedure does have its disadvantages such as the initial cost, need for large machinery and the particularity of holes in the mould. Therefore, it is important to look for expertise, design, performance and cost to get the best quality at the best price. 

Submersible pumps – an iconic addition in the pump parts casting industry

It needn’t be stated that water forms is fundamental for our existence and without a doubt, the most essential amenity that we require to survive. For those of us loving in the cities and metropolitan or even the outskirts, we know the importance of a good and efficient pumping system. We are so used to having this very basic amenity just a lever away that we often take it for granted. The easy availability of modernized pumping systems for our homes and offices has made our day to day lives a whole lot easier.

Acquiring water stored underground and converting it into water that is fit for consumption may seem a simple process, one we hardly ponder over. Yet, it is one process that requires the state of the art technology and skills. At present, submersible pumps are the new in thing. As a matter of fact, submersible pump parts casting have revolutionized the pumping system across the globe. Let’s learn more about it.

What are submersible pumps all about?

A submersible pump also goes by the name of utility pump and that is how it is known worldwide. Also, submersible pumps are electrical devices which are airtight usually. These pumps are used to empty and drain the accumulated water in your offices and homes. The motor in the case of a submersible pump is sealed and attached to the body of the pump. The motor has been designed in such a manner that it is durable and able to withstand the pressure of the water pumping process everyday – both from outside and within the surface of the earth.

In the case of submersible pumps, there are a few major components which must be taken into account. They are – expulsion flow, pumping pressure, horsepower, discharge size and the maximum discharge. Like all other pumping systems, you will have to be cautious while maintaining the submersible pump in order to prevent any kind of leak or damage. Moreover, these pumps come in numerous shapes and sizes depending upon the nature of function they are supposed to perform. In most cases, pumps with half horsepower are more than enough, but if the water levels are lower, you would require pumps with higher horsepower.

Why should you go for submersible pumps?

Now the question might arise, why go for submersible pumps when the traditional pumping systems are working just fine? Here’s why:

·        

Submersible pumps are not dependent on outer air pressure. That makes it all the more       flexible and allows it to suck in more power.

Also, the pump comes with advanced mechanical seals which are highly efficient when it       comes to preventing any kind of a leak. Leaks are always dangerous in the case of any  electrical device, since it may lead to a short circuit.
 
They are relatively low maintenance and are ideal for heavy duty work.

If you haven’t already, it’s time you checked your pumping system and pump parts casting. Submersible pumps are definitely the future of pumping, and you should definitely give it a try. 

Pump impellers - Types and Workings

Centrifugal pumps are the most preferred hydraulic pumps used in the domestic or industrial world. They are used to induce flow or raise the pressure of the liquid, and are used in water, sewage, petroleum and petrochemical pumping. The center to the working of a centrifugal pump is the pump impeller casting. Pump impellers are made of iron, brass, bronze, aluminium or plastic and transfer energy from the motor that drives the pump to the fluid being pumped, which accelerates the fluid outward from the center of rotation. This article focuses on the working of an impeller, its types and workings.

Pump Impeller Casting

 1.  How does a pump impeller work?

Pump impellers are made of brass, bronze, aluminium or plastic and are shaped like small cylinders with an opening. The pump impeller works by the alternating entry and discharge of water into the “eye” of the impeller by centrifugal force. The low pressure created inside the inlet causes more water inflow. This increases the velocity as water flows at a high speed on the shaft. The water is then collected by the volute and converted into pressure by directing the flow discharge into a piping system.

The design of an impeller helps in increasing the flow rate power consumption of the pump stabilisers after reaching the limit point. The inlets accept the incoming fluid, while the vanes push the fluid in a radial direction, and a threaded bore accepts a driveshaft. The projecting “eye” of an impeller helps in a better swirl of the flow with a high negative pressure at the suction.

2.  Pump impeller types

Pump impellers come in specific designs, which depend on the number of points water can enter the impeller and the amount of webbing between the impeller blades.

a.  Single-suction pump – Single-suction pump impellers are designed to have a single opening for the water to enter. The design is suited for higher axial thrust imbalance due to the inflow of water from only one side.

b.  Double-suction impeller – Double-section impellers have a two-sided design for the entry of water. This is a more balanced design, as it balances the axial thrust loads on the impeller and transmits water to the driveshaft to the piping system. If suction is not done correctly, there is the risk of uneven flow on both sides of the impeller.

c.  Open impellers – An open impeller has a single blade or vane attached to a central hub. They have a weaker structure and need higher NPSHR values for proper functioning. They are much more sensitive than closed impellers, and constant erosion may hamper their efficiency. Open impellers are used in small-diameter and inexpensive pumps or in pumps that handle suspension solids.

d.  Semi-open impellers – A semi-open impeller has a circular plate attached to one side of the impeller, with a back for mechanical strength. They require lower NPSHR values than open impellers and are efficient in medium-diameter pumps and liquid with small suspended solids. A small clearance must be provided between the vane and the housing, otherwise, efficiency will be reduced due to overheating and re-circulation of wastewater.

e.  Closed impellers – Closed impellers have circular plates attached to both sides of the impeller, with a back and front wall. They also have wear-rings, which separate the inflow pressure within the pump. Also known as shrouded impellers, they are used in centrifugal pumps that handle clear liquids. They are also efficient in large pumps and suspended solids service, with high wear-and-tear resistance. They are designed to reduce axial load thrust and maintain efficiency.

When choosing the best pump impeller casting, one needs to check for quality material. The casting should corrosion-resistant, durable and sturdy. One should also check the number of blades, impeller dimensions, turbulent power number and flow number for the best performance.