Heading (metalworking)
Encyclopedia
Heading is a metalworking
Metalworking
Metalworking is the process of working with metals to create individual parts, assemblies, or large scale structures. The term covers a wide range of work from large ships and bridges to precise engine parts and delicate jewelry. It therefore includes a correspondingly wide range of skills,...

 process which incorporates the forging
Forging
Forging is a manufacturing process involving the shaping of metal using localized compressive forces. Forging is often classified according to the temperature at which it is performed: '"cold," "warm," or "hot" forging. Forged parts can range in weight from less than a kilogram to 580 metric tons...

, extruding and upsetting process. It is often performed in the cold state, resulting in cold working. This process produces a near net shape
Near net shape
Near net shape is an industrial manufacturing technique. The name implies that the initial production of the item is very close to the final shape, reducing the need for surface finishing...

 workpiece, which means the final product is almost finished.

An important consideration in heading is the tendency for the bar to buckle if its unsupported length to diameter ratio is too high. This ratio usually is limited to less than 3:1 but with appropriate dies, it can be higher.

Older machines are known as single-stroke headers, while newer machines are known as double-stroke headers, because they have two strokes; one stroke moves the workpiece into the machine and the second heads the workpiece.

Two-stroke header

A punch, fixed on a moving block, punches this wire into a die made of tungsten carbide
Tungsten carbide
Tungsten carbide is an inorganic chemical compound containing equal parts of tungsten and carbon atoms. Colloquially, tungsten carbide is often simply called carbide. In its most basic form, it is a fine gray powder, but it can be pressed and formed into shapes for use in industrial machinery,...

, encased by a protective steel covering or a die of any other suitable material to make a plug. Then a second punch presses this plug to form a blank. The shape of the head is formed according to the design of the second punch.
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