Are Forgings Stronger than Castings and Weldments?
For centuries, metal manufacturing processes have been relied on by a number of industries. From transportation and power generation to valves and pipeline equipment, metal manufacturing processes like casting, forging, and welding have been utilized to provide businesses with the parts they need to get the job done. But with so many metal processes to choose from, you might be left wondering which method provides the greatest level of reliability, durability, and strength for your parts.
In today’s blog, we’ll compare these three popular metal processes and discuss how forging remains unmatched.
What are Castings?
Casting is a type of metal manufacturing process in which molten metal is poured into a mold, which contains a pattern that determines the shape of the final product. Parts made from this metal manufacturing process can be used in anything from metal parts for engines and other machinery to jewelry and decorative items.
The casting process begins by creating a mold of the desired object, which is typically made from sand or some other material that can withstand high temperatures. Once the mold is made, it’s filled with molten metal and given time to cool down and harden before being removed from the casting machine where it was created.
Metal castings, also commonly referred to as ferrous castings, can be made from different types of metals including steel alloys like stainless steel, aluminum alloys, copper alloys like brass, and nickel alloys like Monel.
Forgings vs. Castings
While forgings and castings are both metal products, they’re made in very different ways. Let’s take a look at some of the main differences between these two distinct metal processes:
- Forgings demonstrate higher strength. Unlike castings, forgings are able to undergo the effects of hot and cold working. Forging processes thus surpass castings in predictable strength properties, producing superior strength.
- Forgings are flexible. Forging processes like open-die, closed-die, and seamless ring rolling adapt to different production run lengths while allowing for shorter lead times. Special castings require more expensive materials and process controls, as well as take longer to produce.
- Forgings refine better. Casting metals fail to produce either directional strength or grain flow. Casting also fails to reduce or eliminate the formation of some metallurgical defects. Pre-working forge stock, on the other hand, results in grain flow that is oriented in the directions that require the most strength. Alloy segregations, dendritic formations, and other flaws common to metal castings are remedied in forging.
- Forgings are more reliable and less costly. Errors and defects in castings can come in a variety of shapes and sizes. Forged parts demonstrate a more dependable and cost-effective option as the heat treatment refines their grain pattern and provides them with exceptional resistance, elasticity, and high strength.
- Forgings provide a better heat treatment response. Alloy segregation is always a potential with castings. As a result, the melting and cooling operations must be closely monitored. This causes uneven heat treatment responses, which could impair the finished product’s straightness. With forgings, heat treatment is predictable and therefore, you can always count on forged parts to demonstrate superior dimensional stability.
What is Welding?
Welding is a metalworking process that joins two or more pieces of metal together by melting and flowing their edges to form a single, solid mass. Although the process can be done with a variety of tools, including electric arc welding (EAW) machines and gas torches, the most common method for joining metals is arc welding.
Arc welding utilizes electricity to melt the materials together. It works by passing an electrical current through two electrodes that are pressed against the metal being welded. The heat from this process melts both the electrode and the metal being welded, causing them to flow together seamlessly into one solid piece after cooling down again.
Welding is used in construction, manufacturing, and a variety of other industries to connect metal parts quickly and efficiently. It can be done using a variety of different metals and materials, including steel, aluminum, brass, copper, and titanium.
Forgings vs Weldments
- Forgings provide production and material savings. Forged parts are often more cost-effective in high-volume production runs as weldments prove more costly in higher volumes. Forging production also demonstrates lower labour costs, scrap and rework reductions, and reduced inspection costs when compared to welding.
- Forgings are stronger. Weldments are not usually free of porosity and any strength benefit gained from welding can be lost by poor welding or joining practices. The grain orientation achieved in forged parts, however, makes for increased strength and reliability.
- Forgings offer cost-effective designs/inspection. A multi-component welded assembly doesn’t compare to the cost-savings gained from a properly designed one-piece forging. Weldments require costly inspection procedures, especially for highly stressed components, whereas forgings do not.
- Forgings provide more consistent, better metallurgical properties. The selective heating and non-uniform cooling commonly occurring in welding can yield undesirable metallurgical properties like inconsistent grain structure. Forgings, in contrast, have no internal void that can cause unexpected failures under stress or impact.
- Forgings demonstrate simplified production. Welding requires a careful selection of joining materials, fastening types and sizes as well as close monitoring of tightening practices, all of which work to increase overall production costs. Forging simplifies production all while ensuring better quality and consistency.
CanForge – Clear Choice for Quality Robust Forgings
Forging is the clear winner when it comes to making durable, cost-effective products that are built to last. But don’t trust any forging company to get the job done. Choose CanForge. We’ve been producing high-quality, specialty forgings for the most demanding and sophisticated engineering applications for over 100 years. In this time we’ve built a reputation for quality, integrity, and innovation that you can depend on.
Our team has a wealth of experience in all areas of the industry, and we pride ourselves on our ability to deliver exactly what you need – the first time around. Contact us today to learn more about how we can provide the superior forgings you need – high quantities or low.