Precision Investment Casting – The Perfectionist Of All Casting

Vince Lombardi once said, “Perfection is not attainable, but if we chase perfection, we can catch excellence.” And this quote sits right with the ever evolving manufacturing practices. Precision investment casting is one such process that dates back to 1000 BCE in Mesopotamia for art statues. They used the lost wax process back then using bees wax. The term invested basically meant to be surrounded or to be clothed and hence the name- investment casting. Since then the processes have only advanced to arrive at better production practices to attain quality finished products. 

The goal in precision investment casting is to create patterns using wax, which mimicked the parts made from metal to be used in manufacturing, bring them together, layer them with several coats of liquid ceramic, and spray them with sand of the metals. Further ahead, by melting the wax an empty mould is obtained which is used to create metal parts. Considering the finishing levels of the end products, precision investment casting products are widely used across various industrial sectors namely- oil & gas, military & firearms, aerospace, agriculture, food & dairy, and also fluid power.

To have a better understanding of a precision investment casting component, let us recognize its major properties:

• Components that are of complex shapes and tricky features can be cast into one piece using precision investment casting
• Any part that needs shallow depth feature and thin walls can be cast with ease in the precision investment casting process
• The dimensional exactness and tight tolerance is achievable with ease 
• Precision investment casting products have an excellent surface finish. They don’t need a specified post production finishing process
• The raw materials that can be used in manufacturing precision investment casting are endless. Materials used most often are aluminium alloy, cast iron, and non-ferrous alloys. Alloys that require high temperature to be moulded prefer this process of casting over others 
• Precision investment casting products have no parting lines and hence the finished product does not have any flash
• Draft on walls are not required but if a master die is used to make wax patterns then draft on the face would help the pattern making process easier
• Generally, the precision investment casting process is so perfect that the end products do not require additional machining 
• Exceptional dimensional accuracy can be attained by blending very smooth cast surfaces. These competencies are particularly striking when creating products from the high-melting temperature, difficult-to-machine metals that cannot be cast with plaster- or metal mould processes.
• The best part about precision investment casting is that wax that is used can be reused. 

Standard manufacturing practice of a precision investment casting goes through the following steps to get the finest results:

• The first step is creating the pattern using the injection moulding technique
• The next step is to mount wax patterns and create a tree. A wax tree can have many precision investment casting parts depending on their size
• The third step is creating the mould shell is created by dipping the wax shell in slurry sand like stucco and silica. After the shell has dried, the process is repeated to achieve the desired thickness. The inside of the mould is kept hollow and layered with fireproof material
• The coated shell is now left to dry, for the metal to harden and for the wax to melt. Generally, the wax is collected to be reused
• Testing is the next logical step. Water is poured in through feeders to check for cracks if any. And if cracks are found, they are patched up
• The shells are reheated to get rid of leftover moisture and then molten metal is poured into shells while they are hot
• After the process is complete the casting is removed by the blasting method
• The final step in the precision investment casting is to finish the surface of the product by smoothening it 

Rajkot, a city in the state of Gujarat is a hub of hardware manufacturing in India. Rajkot is the perfect geographical location for precision investment casting production considering its ease of access to international airports and a seaport. Also, due to the easily availability of the skilled labour in Gujarat, precision investment casting is a business of choice for many. One such quality manufacturer is Sumangal Castings Pvt. Ltd, part of a conglomerate – Sumangal Group manufactures of precision investment casting products. It is significant to mention here that they are one of the pioneers of precision investment casting in India. As a leading precision investment casting company, Sumangal Castings Pvt Ltd is also an exporter of precision investment casting parts. And hence makes them the best option to consider for your precision investment casting needs.