How Does Sand Casting Work?


Sand casting is a process that has been used all over the world for hundreds of years. However, not everyone is aware of exactly how sand casting works. 

This article takes a brief look at how this method works and what it’s used for.

What Exactly Is Sand Casting? 

Sand casting is a method that is used as an alternative to diecasting. This process involves workers pouring molten metal into a cavity. The cavity in question has been molded with sand. Sand castings are usually very tough and able to help people create elaborate and large products. 

How Sand Casting Works 

Sand such as silica sand or green sand is pressed into 2 matching plates. The sand is pressed tightly into these plates to make sure that a pattern is effectively created. 

Once the sand has been poured into the molds it is left to harden. As soon as the sand is hard enough it is ready to be used. The match plate or castings are sealed so that they can be used to create a product. 

The next stage involves pouring molten (melted) metal into the casting. The metal is then cooled and the product is then removed from the mold. Occasionally coatings and paints are added to the product so it can be used as required. 

The Sand Casting Process 

Let’s take a look at the sand casting process:

1. Producing the required pattern – A reusable pattern is used to ensure that the finished product has the same pattern and is the same size as the mold. 

2. Delivering the molten metal – The flow of the molten metal is managed using pathways, helping to create an accurate design. 

3. Creating the mold – The mold is now created at a very high temperature. The sand is strong enough to take the weight of the molten metal that is poured in. The mold is made in 2 halves and joined together at a later stage.

4. Adding the molten metal – The metal is added to the mold, filling the cavity completely. The risers that feed the metal into the mold become solid and are the last thing to cool. This allows for the molten metal to flow smoothly into the mold. 

5. The shakeout – At this stage, the sand is removed using a shakeout process. The sand can then be reused another time. 

6. The next steps – The next steps in the sand casting process are the final ones. They involve the runners and everything else being removed from the casting. The finished product may then be varnished and/or painted. On some occasions, the cast may even be heat treated. This helps to improve the product’s stability.

As you can see, the sand casting process involves a lot of different steps. While it may seem like a lot of work, sand casting is one of the most reliable methods to use. It helps to produce high quality materials for many industries that are strong and perform well.