Sand casting is the most popular and widely used method of creating expendable molds. With 60% of them being made this way. The following advantages separate it from other manufacturing processes from a production perspective:
These advantages make it a favorable process choice for manufacturers. However, there are several types of defects that are often associated with the problems such as shrinkage, porosity, pinholes, and improper filling.
These defects may lead to poor mechanical properties for the casted parts. What many do not understand is that these defects are not inherent to sand casting, but are the result of poor pattern designs, subpar workmanship or lack of quality control. These defects are typically caused by poor gate design systems which are implemented in patterns.
To produce high-quality casted products, the mold should be filled with molten metal as quickly as possible, but without increasing metal temperature, head pressure, or causing turbulence in the metal flow. These conditions can be achieved through proper gating patterns, including the pouring basin, sprue, sprue base well, runner, runner extension, gate, and riser.
In some cases, internal surfaces will be created separately instead of being included in the pattern.), the metal is poured into a mold via the pouring cup, passes down the sprue (i.e. the vertical part of the system), and then passes through the runners (i.e. horizontal portions of the gate system). Vents allow gases and air displaced by construction to escape. In the mold cavity, the gates are the multiple places where metal is introduced by the runners.
Vents allow gases and air displaced by construction to escape. After cooling, the mold is broken open, and the casted part will be removed. Castings are shaken out to remove sand.
The optimum design may affect both mold filling and head pressure but will have a huge impact on the product quality. Improper gate patterns can lead to turbulence in the molten metal, which causes the formation of oxide films, air entrapment, and sand inclusion defects.
A precise and well-designed system is essential to good quality and outstanding performance of the sand casting process with consistently uncompromised mechanical properties.
Depending on the design, novel gating configurations such as the top bottom and side gating may also be used. In the right circumstances, these configurations are very effective in preventing defects, but it should be noted that they are highly dependent on the part geometry and size.
Furthermore, scientific research has found that the use of different gating configurations may produce substrates with varying microstructures, which gives slightly different mechanical properties (including tensile strength and hardness) across the final product. So, it is fair to say the choice of choosing a proper configuration and design is absolutely critical to producing consistently high-quality casted products.
Combined with our excellent metal casting craftsmanship, rigorous quality control protocols and professional project management, we have full confidence in delivering top-tier products for any project.
Omnidex works collaboratively with clients to optimise the best-suited pattern and molding method for each custom casting project. Request a Quote to get more information on how our casting service can match your project requirements.
mechanical properties
Omnidex is a World-Class Manufacturing and Engineering company that produces high quality, porosity-free casting products which are trusted by companies across different industries. Throughout the whole process, from product development to delivery, we strive to provide you with unwavering support. Providing you with unmatched diverse capabilities and experience, we help you overcome any obstacle.
Contact our Customer Service and let us know how we can help to catapult your next project to success.
If you are looking for metal casting services, our brochure is a great way to discover what Omnidex has to offer. You can download HERE or EXPLORE HERE to learn more.
Copyright © 2022 Omnidex Group. All rights reserved.
If you are looking for metal casting services, our brochure is a great way to discover what Omnidex has to offer. You can download HERE or EXPLORE HERE to learn more.
Copyright © 2024 Omnidex Group. All rights reserved.
