Precision casting, sometimes referred to as precision investment casting, is a technique used as an alternative to forging and sand casting. Zehan Casting is one of the leading precision casting providers in China. In this write-up, we look into the ins and outs of precision casting .
What is precision casting?
Precision casting, otherwise known as investment casting, is used to make ferrous and nonferrous metal casting. It is generally a lost wax casting technique.
A breakdown of the process
Below is a breakdown of the process of precision casting;
- The first step of the process is the creation of the mold design. Before the mold design is created, the engineer has to create a drawing with the design first. From there, the drawing is applied in making the mold design. Once the mold design is complete, the rest of the process can continue. Note that the mold design significantly affects the outcome of the process. Therefore, if there are any issues with the mold design, there will be severe implications on the final product design.
- The second step, equally as important, is the injection of the wax into the mold. Here, a machine is used to inject the wax into the mold. Injection molding is applied in this step. Through injection molding, the desired wax design is produced. The designs produced on this step are known as patterns.
- Here, the patterns created in the step mentioned above are used to a central wax stick. This wax stick is known as a sprue. This step of the process is known as the assembly tree. The same name is used for the outcome or the product of the process.
- The shell is constructed by dipping the assembly tree in a liquid ceramic slurry. It is then immersed into a bed featuring fine sand. Here, up to six layers can be applied. As each latter is produced, the shell dries in the process.
- The next step is dewaxing, which is done by introducing heat. The heat melts out the wax from the shell. Afterward, the shell is filled with molten or liquid metal through gravity pouring. The molten metal is then allowed to cool as the solid casting is produced. After the metal has completely cooled and solidified, it is broken off using vibration. A knock-out machine can also be applied.
- Finally, the parts are cut from the central spruce. This is done by utilizing a high-speed friction saw. Afterward, the cutting off, the pouring part of the casting, is ground keenly.
After the entire process is complete, the metal casting is inspected. The role of inspection is to ensure that the final product is similar to the drawing. The quality is also checked to ensure all the requirements are met. If there are any issues with the final parts, they are repaired and inspected again. Doing this ensures that all the products or parts are in top-notch shape before the process is declared complete and successful. Doing this helps minimize the chances of defects in the parts created.