A foundry is an industrial factory which creates metal castings from various molds. Metals are first heated to a specific temperature in a furnace to form molten metals into a solid mass. The most commonly used metals processed are iron and aluminum. After these metals are cooled, they are then given an injection of molten tin-zinc alloy and pushed through a casting machine which is shaped by a die. This process generates high-quality metal casting parts for machinery, automobiles, and even electronic devices.
Divided into two main categories
A foundry can be broadly divided into two main categories based on the way in which the metal is processed – either by compressing the molten metal into a mold in a process known as casting, or by direct heating the metal with a furnace. Cast metal and sheet metal are usually foundry products. Casts can be made by hand or by machine. In the case of sheet metal, two or more pieces of the same size are placed in a crucible, which is a container filled with tungsten.
Manufacturing metal castings was by hand
In the past, the most popular way of manufacturing metal castings was by hand. A worker would manually mix a furnace ash into molten metal and push it through a mold to create a metal part. After the material cooled, the mold is removed, and the piece is ready for use. Today, with advanced machines, the procedure is more mechanized. Instead of manually mixing the ash into the mold, the furnace burns the ash into the metal to form a particular thickness. A metal press is used to press the pieces into the mold material.
Casts are often used to make roofing tiles, pipes, stairway steps, car parts, and decorative objects. A foundry can vary from traditional furnace casting foundries to wireline casting foundries, with regard to the basic layout of the foundry processes. Most of the time foundry operations are carried out at low temperature and high speed.
Abrasive flow or sand casting
Another type of foundry process is called abrasive flow or sand casting. This process generates a lot of heat and the molten metal is allowed to cool at very high velocities. After the metallic particles cool, they are reshaped into various shapes and sizes, depending on the need. Some of these materials are used in jet engine designs.
When it comes to the variety of metals that can be called through this method, you will be surprised to know that there are so many options. One example of this is steel, which can be casted into bars, tubes, sheets, fins, blades, landing gears, etc. Copper is another popular metal that is commonly produced in this way. There are other metals like brass and bronze that can be foundry heated to extreme temperatures, but you can’t use these metals in ordinary furnaces as they don’t have the melting temperatures needed to produce castings in those metals.