Consumer demand for high-quality products is increasing all the time. So, what is the company’s strategy for meeting these consumer expectations? Of course, there are many factors that influence quality improvement when producing a quality metal casting product, one of which is the design of castings.
The initial process in metal casting that affects the final product is casting design. The pouring channel system’s calculation, the casting channel’s addition and layout, and the addition of an effective channel are all performed during the casting design process.
Why is casting design so important in the metal casting process?
Here are some of the advantages of casting design:
1. Reduce Turbulence
The turbulent flow will cause mechanical effects and excessive heat on the mold. As a result, gases will be trapped, resulting in gas hole defects and inclusions in the casting product.
2. Mold and core erosion prevention
High flow velocity or flow direction hitting the mold or core will cause erosion and casting defects.
3. The best thermal gradient
A thermal gradient is a temperature change that varies with direction and speed. The channel system is designed to provide an orderly sequence of heat, beginning with the thinnest object, then the thicker part, and finally the enhancer, with the enhancer expected to be where the liquid last freezes. Hotspots on objects will be prevented by successive thermal gradients.
4. Maximum yield
A metal liquid that fills the pouring and enhancing channels is an unavoidable cost in metal casting. Later, these pouring channels and enhancers can only be re-melted, and if sold, they have a lower price.
The following advantages can be concluded from the benefits listed above:
“Casting design can help to reduce casting defects and production costs.”
The adder calculation and the channel system are two critical aspects of metal casting. Both are critical in controlling the rate of metal liquid entering the mold cavity, as well as the process of solidification or freezing liquids to produce defect-free casting products.
The enhancer and channel systems operate on the following principles:
- The duct system must be capable of draining and distributing the liquid evenly and calmly within the mold cavity.
- The pouring time is calculated so that when the pouring process is completed, the solidification of a new liquid begins.
- The adder is a component of the metal pouring system that requires the longest solidification time.
System of Enhancement
The enhancer system is made up of the following components:
- Parts of cast products that require fluid intake during the solidification process;
- Neck enhancer, that is, the part of the enhancer that connects the cast product to the enhancer;
- An enhancer (riser) is a component of the casting design system that is used to supply cast objects while they are still liquid. The adder is critical in balancing the volume of fluid to avoid shrinkage defects. To provide a supply until the cast object freezes, the adder must freeze at the same time or later than the cast object.
The side and upper enhancers serve the same purpose: they supply cast objects. The only distinction is the position. The shape of the cast object determines the adder’s position.
System of Pour Channels
The pouring conduit system is a channel system that allows molten metal to enter the mold and flow into the cavity. After that, the metal liquid freezes to form the desired casting. A simple pour channel system for molding is divided into three parts: the descending channel, the dividing channel, and the inlet. Here’s how it works:
- The Descending Channel (sprue) directs the metal liquid that is poured into the dividing channel. To facilitate the pouring process, a pouring basin is constructed at the top of this channel.
- The dividing channel (runner) distributes metal liquids as they approach the mold cavity parts designated as entry points. This channel can serve as both an entry point and a slag/dirt trap at the same time.
- An inlet (in-gate) is a channel that is placed on parts of the mold cavity in such a way that the inflow of metal liquid into the mold cavity is calm, homogeneous, and evenly distributed in volume and temperature.
The descending channel supplies the liquid metal channeled through the dividing channel, which is how the pour channel works. The liquid is then distributed throughout the mold until it reaches the product cavity via the inlet.