Difference Between Casting and Foundry: when we are talking about metal manufacturing, two terms frequently occur together: foundry and casting. Individuals engaged in the working environment in engineering, manufacturing, metal fabrication, or supply chain procurement should understand the distinction between them. One of the most ancient and important processes of manufacturing in human history is metal casting. It enables the raw metal to be converted into well-formed, hard-wearing industrial and commercial products that are very accurate. However, the word casting is commonly used meekly, yet there is a difference between casting as an action and casting foundry as the establishment where the casting process would be undertaken. These two go hand in hand but are essentially different.

Casting is the pouring of molten metal into a mould with the design of making it into a particular shape, whether they are a gear, a fitting of a pipe, or a complex piece of an engine. It is one phase in the manufacturing assembly. On the contrary, a foundry is the location where this process takes place, and many others related to it, such as melting, mould preparation, finishing, and quality checks to take place in a coherent, scalable way. Knowledge of the difference between the casting and foundry activities is of utmost importance in terms of production planning, cost estimates, or supplier selection.

In this article, the author defines a foundry, its main stages, and how it differs from the general concept of casting.

What is Foundry?

A foundry is a metal casting site. It is where that molten metal is poured into moulds to create complex parts and shapes, in an industrial facility or workshop. Some of the industries that heavily rely on foundries are the automotive industry, aerospace industry, construction industry, agricultural industry, as well as the energy industry.

Foundry Process Overview

A normal operation of a foundry involves the following steps:

1. Pattern Making: Developing a copy of the last section.
2. Mould Preparation: Casting in the mould cavity, that is, sand or metal.
3. Metal Melting: Molten heating of metal.
4. Pouring: Pouring molten metal into the mould.
5. Cooling and solidification: leaving the metal to cool down and harden.
6. Cleaning and Shakeout: Scraping of the mould and cleaning.
7. Processing, Shipping, and Inspection: Grinding, machining, and quality check.

A foundry is a very technical sort of environment that combines cutting-edge engineering with metallurgical science. They consist of small workshops to huge industrial plants capable of making thousands of castings a day.

Types of Foundries

Foundry. There are several varieties of foundries specializing in different types of casting:

• Ferrous Foundries:  Sculpture with iron and steel.
• Non-Ferrous Foundries: Concentrate on aluminum, bronze, and other alloys.
• Jobbing Foundries: Make productions in small quantities or customer-specific parts.
• Production Foundries: Produce a large quantity of components.

The Metals That Are Usually Used in Foundries

Depending on the application, foundries work with a lot of varieties of metals to work with. The most widespread ones are:

• Cast Iron: Also renowned to be easily castable and to create vibration damping.
  Cast Steel:  It provides more strength and toughness.
• Aluminiumlegeringen:  Corrosion-free and lightweight.
• Bronze and Brass:  They are commonly applied to ornamental or abrasion-resistant parts.
• Magnesiumlegeringen: Lightweight and not as widely used because of the risk of flammability.

The various metals have different behaviours in the molten state, and therefore, the foundries need to consider particular handling, melting temperature, and mould materials.

Important Processes of a Foundry

A foundry process comprises various fundamental processes, all of which are requisite to the quality and precision of the end casting:

1. Pattern Making  

A pattern is a copy of the last object being cast. It is employed to make the mould cavity. The patterns may be wooden, plastic, metal, or even of wax, depending upon the casting technique.

2. Moulding  

This means that a negative impression of the pattern would be made on moulding material, i.e., sand or ceramic. Two types of them exist: 

Green sand molding: Green sand moulding uses sands with little to no binder, and is a process used in making an ASTM A588 box or ASTM A370 box (pictured), a high-strength cast iron produced by casting into moulds implanted with cast steel axle boxes, which in turn are set in sand.  

3. Fusion and Pouring  

Furnaces that they use to melt the metals include induction furnaces, electric arc furnaces, or cupola furnaces. After being molten, the metal is either poured into the mould with the help of gravity, pressure, or vacuum.

4. Cooling-down and Solidification  

The metal then solidifies into the shape of a mould after pouring. The allocation of grain structure and mechanical properties, and surface finish is due to the cooling rates.

5. Cleaning and Shakeout  

The mould is disassembled (in case of disposable ones), and the solidified bit is taken out. Sandblasting, grinding, or treating with chemicals are the processes of cleaning casting.

6. Checking and Polishing  

The last processes involve dimensional process, non-destructive tests, heat treatment and machining. Any faults, such as porosity or contraction, are pointed out and rectified.

What is casting?

The actual process of forming a metal object through pouring molten metal into an object is known as gieten. It is the process or method, not the place, in which it is performed. Castings may be done in a foundry, or they may also be done in non-foundry shops or production lines.

Simply put:

• The place is a foundry. The process is called casting.
• Several types of casting may be classified in general.

Types of Casting Methods 

Casting can be performed in a couple of ways. These include:

1. Zandgieten

It is one of the most ancient and multi-purpose techniques. Metal components of shapes and sizes can be made by a sand mold.

2. Die Casting

Refers to the actions of forcing molten metal into high-pressure reusable steel moulds. Typical of high-volume aluminum, zinc, and magnesium alloys.

3. Investment Casting ( Lost Wax )

Has great accuracy and is applied in the aerospace and medical industries. Wax patterns are ceramic-coated, and the wax melted away, leaving a cavity.

4. Permanent Mold Casting

Fills cavities through the use of gravity or low pressure, and the use of reusable metal cavities. It is more dimensionally accurate than sand casting.

5. Centrifugal Casting

Centrifugal force is used to cast the parts, shaping molten metal through the spinning mold. Suitable when dealing with cylindrical components, such as pipes or bearings.

What is the difference between a foundry and casting?

Table 1: Difference between a foundry and casting

The Reason why people mix up Foundry and Casting?

The inseparable association between the two words, foundry and casting, sometimes comes as a result of how the words are used by informal language and their description in the advertisement. The terms casting factory or casting plant are easy to substitute for one another, especially if one means a foundry.

In addition, given that the major process that occurs in a foundry is casting, the two words become highly synonymous. Nevertheless, to people working in the sector, the separation is useful in defining roles, responsibilities, and procedures.

Utilization of Foundry and Casting in Real Life

Casting is one of the basic manufacturing processes that support various industries. Foundries are an enervating part of the heavy industry and also the light industry. Some of the main areas that depend on cast components are as follows:

1. Auto-industrie

The cast parts are extensively put in usage in the engines, transmission systems, chassis, and suspension parts. Typical ones are:

• Motorblokken
• Cilinderkoppen
• Brake drums
• Gearboxes

This space is occupied by aluminum and iron castings, which are strong, inexpensive, and well-machined.

2. Aerospace

Aerospace requires lightweight as well as high-strength parts. Investment casting and other precision casting processes are used.

• Turbine blades
• Jet aeroplane parts
• Structural brackets

In this case, systems of dimensional tolerance and fatigue resistance are also considered, as well as the mechanical strength.

3. Infrastructure and construction

The purposes of using cast iron and steel in the construction include:

• Water pipes
• Drainage systems
• Support structures
• Manhole covers

This makes them long-lasting, and they are suitable for the infrastructure project because they survive in a hard environment.

4. Power and Energy

In thermal, hydro, or wind-powered power plants, castings can be found in:

• Turbine housings
• Klephuizen
• Pump casings

It is based on the casting process that a large, complex shape that can withstand high levels of pressure and temperature can be made.

5. Agricultural Equipment

Because of their strength and wear resistance, heavy cast iron or ductile parts are used in tractors, plows, and harvesters. The parts that are made in foundries to aid this sector are:

• Gear housings
• Axle components
• Counterweights

The merits of Foundries and Casting Processes

The casting procedure contains several strong advantages that render it perfect for a wide array of manufacturing projects:

Ontwerpflexibiliteit

Manufacturers use casting to achieve large surface areas and complex geometries, internal cavities, and other complex shapes that are tricky or costly to manufacture using machining or welding.

Large Variety of Materials

Casting can be used with ferrous and non-ferrous metals as well as exotic alloys. The foundries have the option of tailoring the materials to suit the performance demands, such as heat resistance, wear resistance, and corrosion resistance.

Kostenefficiëntie

Casting is more cost-effective as compared to other methods of manufacturing, especially at large levels of production. When the mold is produced, further manufacturing is quick and affordable.

Minimal Waste

In the majority of contemporary foundries, effective recycling is introduced. Scrap metals can be melted and reprocessed, making raw materials cheaper and minimizing the damage done to the environment.

Scalability

Foundries have the flexibility of going from small production to mass production with relatively little change to the process, making foundries a prime choice in prototyping full-scale productions.

Limits and Negatives

Indeed, as versatile as casting is, it does not go without its set of limitations. Knowledge of the disadvantages is central in the selection of a suitable manufacturing process.

Dimensionale nauwkeurigheid

Some shrinkage and warping can be expected depending on the method of casting as used. Tight tolerances usually involve a subsequent process such as machining.

Afwerking oppervlak

Cast surfaces are frequently necessitated to undergo secondary processing such as grinding or polishing, particularly when sand-casting.

Largest startup tooling cost

Molds and patterns may be very costly and time-consuming in processes such as die casting and investment casting.

Defecten

Porosity, shrinkage, hot tears, or inclusions could arise and compromise the integrity of the resulting product unless these issues are tackled effectively in the manufacturing process.

Selection between Casting and Other Manufacturing Processes 

The selection of casting as opposed to forging, machining, or fabrication is dependent upon many factors:

Table 2: Selection between Casting and Other Manufacturing Processes 

Nevertheless, in uses where very high mechanical strength, precision, or surface finish are required, casting may need to be replaced by forging or CNC machining.

Modern Trends and Automation in Foundry

Modern foundries, like any other industry, are fast developing with advancements in technology. Among the main trends, there is:

Smart Foundries (IoT 4.0)

Quality control and productivity in foundries are being transformed by the implementation of IoT sensors, real-time data capture, and predictive maintenance.

Patterns and molds using 3D Printing

Additive manufacturing has become a method of producing patterns directly and now even casting molds, currently shortening the lead time and prototyping expenditures.

Duurzaamheid

Foundries are becoming cleaner in production through things such as electric melting furnaces and better dust/particle emissions control.

Simulation Software

Using sophisticated casting simulation software, engineers can see metal flow, solidification, and possible defects well before they go to manufacturing to create less waste and enhance quality.

The Future of the Foundries in Global Manufacturing

Although more sophisticated processes for the fabrication of parts have overtaken the made foundries the foundries are still vital. They can create powerful, big and complicated parts of metals at a large scale that makes them remain relevant in industries. They are becoming smarter and more sustainable through digitalization inventions, manufacturing sustainably, and using artificial intelligence in process control.

Also, the increasing popularity of electric vehicles, wind energy installations, and the enhancement of the aerospace domain further contribute to the increasing demand for high-performance castings.

Overview: Some of the Main Disparities between Foundry and Casting

Table 3: In a  recap of the main differences:

In short:

Casting takes place in a foundry. Casting is the process in a foundry.

Laatste gedachten

The distinction between foundry and casting is not just semantic; it is essential to engineers, purchasers, and manufacturing companies. The foundries are large-scale production facilities where the casting process is carried out professionally, safely, and consistently. When it comes to sourcing parts, supplier evaluation, and improving manufacturing processes, the benefits of understanding the specific functions of each of these terms can result in an increased level of success and even better quality of a product.

Frequently asked questions 

1. Does casting and foundry mean the same?

No. The process is casting, and the place where casting is carried out is a foundry.

2. Is it possible to cast without the use of a foundry?

Casting of any sort, even in modern manufacturing times, can never be in an open field, as the equipment and safety requirements require this to be in a foundry.

3. Is it more complicated to cast or operate a foundry?

Foundry is even more complicated since it processes the entire lifecycle of product design and completion, including quality management.

4. Is there any foundry that does not just cast?

Yes. Surface finishing, machining, and heat treatment are also widely available in many foundries.

5. Should a metal part be called a cast or a foundry part?

The process can be denoted by use of the cast part, whereas foundry-made is an alternative when it is important to denote origin or manufacturing quality.