Dec 2016

Know more about lost wax investment castings

Lost wax investment castings are known to be one of the oldest known processes for metalworking. In this historical process bee wax was used to form a pattern and then various components and products were created.


However, there are innovations being introduced by casting foundries like advanced refractory materials, hi-tech waxes, and other such advancement that is made possible with the help of computers and design possibilities.


Now you can prepare your casting solution with lost wax investment casting. It is also known as silica casting and de-waxing casting process. Through the casting process, you need to ensure proper measurement and customization of the products and in this regards you can use the lost-wax investment casting.


With this casting process, you can furnish the finest surface with lower machineries and you can prepare super quality casting materials as per the industry norms.


Features of investment casting:


  • Proper design


Similar to every other casting designing is the first thing that takes place. It is a drawing for a new process or an existing prototype that can be used for similar projects. This is an intricate process as every other detail depends upon the right design and proper specifications. With the investment casting process, you can ensure the proper design of the products such as various shapes, designs and size of the products accordingly.


  • Making of the mold


Once the design is complete the lost wax investment castings foundries focus on mold making. An injection mold is produced with the help of a drawing, a prototype or a new computerized design. It is a wax pattern injection and it is then machined by using the computer assisted designing and then manufactured. This is the best fusion of innovative technology and ancient science.


  • The wax pattern assembly


In this assembly various wax pattern injections molds are assembled on a tree or a spruce in order to form a full part. This forms a dispensable pattern to be followed in the next process. Through these lost wax investment casting, you can minimize your production investment and you can create the products as per the company requirement only. The manufacturing company shall provide the specification of the mold and you just need to follow the guidelines to produce the casting products accordingly.


What are the processes of lost wax investment casting?

Primary slurry or a ceramic shell is applied to the spruce or tree. This process helps to coat the wax assembly with a very fine ceramic liquid. When the slurry is still wet it is covered in sand and then allowed to dry for a while before some more slurry and sand is applied to the same.


  • Removal of wax


In the next process the ceramic shells are prepared for the wax assembly to be removed from the inside. An autoclave is used to do this and here the ceramic shells are put on a tray and the wax inside the mold is melted with the stem from autoclave.


  • Burnout with high temperature


Once the wax is melted the ceramic molds need to be cured and for that the ceramic shells are subjected to high temperature burnout. Once this process is done they are then carefully prepared for casting and pre heating process. Afterwards you can use the shape for preparing or accommodating the products accordingly.


  • Melting and casting of metal


In this step of the lost wax investment casting process line furnaces are used to melt high quality alloys. In order to get the best quality of casting this step is highly critical and precision is needed to get the best results. In this process, alloying and degassing are performed in order to make sure that the properties of melted metals are optimal for pouring. Once everything is made sure then the metal is casted in the ceramic mold.


  • Cooling off


Once it is cooled the metal casting then takes shape of what the wax pattern looked like. After the process of lost wax investment casting is cooled the ceramic shells are then taken out with the help of high pressure water jets. This leaves the complete metal casting for the foundries.


  • Final touches


A saw is then used to cut off any unwanted gates and is further given final touched with the help of grinding. Then to give it the perfect shape de-burring, machining and hand tooling is used to give a perfect shape to the casting.


How has advancement in technology helped?


The advancements in processes, wax, pattern making, melting equipment and things like these have resulted in complex process that can help to hold even extremely dimensional properties. The modern lost wax investment castings can measure even a thousand of an inch dimension and this result in getting precision results at the end. This helps to make components that can be directly used after receiving from the manufacturers.


Application of investment castings


In our modern times the application of lost wax investment castings has increased tremendously. These are used to create precision components in the field of aerospace, material handling, transportation, food processing, pump and valve, and complex areas like these. These fields need precision castings and so they need nothing but the best to fulfill their needs.


Original art and the sculptures also need the help of lost wax investment castings in order to create a metal version of this artwork. Even when the medical components and implements are needed in human bodies the lost wax investment castings are used in order to get precise results. Apart from that, for industrial manufacturing units such as preparing molding products, shaping the products as per the requirement and manufacturing the raw materials as per the desired shape and investment casting is needed.


With every passing year we are seeing improvements in the process and the cost needed for investment castings. The equipments needed to produce these are also improved on a regular basis in order to produce castings on high or low volumes according to the client’s specific requirements pertaining to their field of operation.