Forging Processes Guide

Forging refers to the forming and manipulation of metal through the use of directed compressive forces.

We primarily specialise in hot upset forging by using numerous on-site forging processes detailed below. Offering superior strength through compressed material grain flow, forged components are used in many industries worldwide.

Please contact us today for more information, our technical department can advise the best forging process suitable for your components.

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The Upset Forging Process

Upset Forging is accomplished by holding pre-heated material between grooved dies, commonly known as ‘grip dies’. Pressure is then applied to the end of the bar in the direction of its axis.

The Heading Tool upsets the end of the bar by displacing the heated metal within a cavity. It’s not uncommon to have several upsetting operations on one die set, gradually forming the bar to its required shape.

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The Drop Forging Process

The Drop Forging Process also referred to as Closed Die Forging, is a process that manipulates a heated metal bar, pre-form shape, or billet within the wall cavity of two dies.

This process is also referred to as impression die forging.

The impression for the forging can be in either die or divided between a top and bottom die, as shown in our illustration.

During this process, the material grain structure becomes compressed and aligned to the required component shape. This greatly improves strength and resilience.

Components manufactured using the drop forging process are stronger than their equivalent machined from solid or cast parts.

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The Horizontal Counterblow Process

Counterblow forging machines operate on the basis that two bodies of equal mass are accelerated towards each other at the same speed. When they collide the reaction forces are equal and opposite to each other concentrating the complete absorption of energy within the bodies themselves. When forging stock is placed between the bodies, it is deformed by the impact energy created by the blow.

The impact energy is pre-set and is regulated by precise timing controls to provide consistent energy levels for metal deformation. Savings are made because only the required amount of energy is used for the size and complexity of the product being manufactured.

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The Open Die Forging Process

Open Die Forging is one of the oldest forms of manufacturing, using traditional blacksmith methods to manipulate and refine grain flow.

The billet is heated above the recrystallization temperature, ranging from 1000°C to 1300°C for steel, and gradually shaped by skilful hammering or pressing of the workpiece to create the desired shape.

This process elongates and compresses the grain flow as shown in our illustration, improving the mechanical properties to add strength and resilience.

Open die forgings are commonly selected where conventional forging processes are not suitable, such as limitations due to size and complexity, and are typically machine finished to the final desired shape.  In some scenarios, the material grain flow is still broken and exposed during the machining process but the final component still benefits from grain flow compression.

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The Swaging Process

The Swaging process typically involves working solid or tubular material in the cold or heated form to reduce the diameter, produce a taper, add a point, or other desired shape.

With rotary-based swaging machines, two or four split swaging dies are used to hammer a round workpiece into a smaller diameter, as shown in our illustration. This process is usually called rotary swaging or radial forging and can operate up to 2,000 motions a minute.

We also have in-house forming methods that can be adapted to perform a swaging process where conventional processes are not suitable.  For example, reducing solid flats to form a round bar section at one end.

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Hammer Forging

Forging hammers operate using a vertical ram. When it moves in a downwards stroke it exerts a striking force, against a stationary component of the anvil, near the base of the hammer. This is the most common production process for Closed Die Forging, using repeated blows to obtain a filled cavity. The impression for the forging can be in either die or divided between a top and bottom die, shown in the diagram above.

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Press Forging

Forging presses incorporate a vertical ram which exerts a controlled squeezing action on the workpiece in contrast with repeated blows of a hammer forging.

In general, presses can produce all types of forgings produced on hammers, with the advantage of forging alloys with moderate ductility that would commonly shatter under the blows of a hammer.