Joshua Bigwood & Son Limited

High Efficiency Precision Forging Machine

The Bigwood High Efficiency Precision Forging Machine was designed to produce an endless variety of close tolerance forgings that were extremely accurate, so accurate in fact that machining was not necessary. The machine was much more versatile than the usual Upsetting type of forging machine, due to the exceptionally large die space and gathering capacity. The dies were easily accessible to reduce the time necessary for changing and setting up the tools. The machine was equally at home on a mass production line or when only a few forgings of one size were required.

The long hanging heading slide moved on narrow guides to ensure a straight line movement and accurate registration of the dies. The die slide was operated from a single cam on the crankshaft and via a double toggle joint mechanism to provide an extremely powerful and precise gripping action over the whole length of the dies.

An automatic stock gauge between the dies and heading tools could be adjusted by hand to enable the operator to gauge exactly the amount of material that was required for a given forging.

Several safety devices were fitted including a brake at the end of the camshaft which held the crank securely in its neutral position. The balanced flywheel was of the safety-slip type which safeguarded the machine in case of overload. A safety trip was fitted to the operating gear and a safety device was fitted to the die slide closing mechanism.

The long hanging head slide prevented any misalignment of the heading tools.

Capacity up to 2 inches diameter
9 inch stroke
55 strokes per minute
6.25 inch gather
3.75 inch die opening
Flywheel rotated at 220r.p.m.
Flywheel diameter - 3ft. 4in.
Power - 18h.p. 

The company also produced a range of machinery for the forging industry, including power hammers, plain and automatic drop stamps, bulldozers, forging rolls, and hot saw and burring machines.

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