Creusot steam hammer
The Creusot steam hammer is a giant
The Creusot hammer is no longer operational, and is a tourist attraction in the town of Le Creusot, where it was built. With few remaining rivals, the hammer today is once again the largest of its kind in the world.
The Creusot steam hammer was named a
Origins
In 1836,
The Creusot steam hammer was completed in 1877, and with its ability to deliver a blow of up to 100 tons, eclipsed the previous record set by the German firm Krupp, whose steam hammer "Fritz", with its 50-ton blow, had held the title as the world's most powerful steam hammer since 1861. In celebration of this technological achievement, a full-scale wooden replica of the Creusot hammer was built and displayed at the Paris Universal Exposition of 1878.
Description
The hammer is composed of four distinct parts — the foundation including the
The anvil weighed a massive 750 tons, and in order to support the weight and the hammer blows, the machine's foundations were built of solid masonry resting on bedrock 11 meters below the soil. A one-metre thick bed of oak timber topped the masonry foundation and provided the immediate floor for the giant anvil.
The four legs are hollow cast and rectangular in cross-section. They were originally bolted to plates embedded in the masonry. The legs are 10.25 meters high and connected to one another at the top in a rigid A-frame design by a 30-ton "table", that in its working life both guided the hammerhead and distributed the shock of its blows. One leg supports the operator's platform from which the machine was controlled.
The steam cylinder itself is 6 meters high and has an inside diameter of 1.9 meters. Steam pressure averaging 5 kg/cm2 or 71 psi drove the cylinder upwards through two balanced single-acting slide valves, after which the force of gravity would allow the hammer to fall and deliver a blow.
The piston had a maximum travel of 5 meters and the piston rod was 35 centimeters in diameter. The hammerhead or tup was interchangeable, with a number of differently shaped dies which may account for the hammer's reported variable force of between 75 and 100 tons. The actual energy delivered may have been in the order of 3.3 million
Four separate
For a comparison of scale, the world's largest modern hydraulic forging presses can apply force of about 80,000 tons.
Demonstrations
In its heyday, the hammer would sometimes give public demonstrations of its accuracy. It could be used to cork a bottle, crack a nut without damaging the contents, or tap a watch glass without breaking it. With such demonstrations, steam hammers for a time became symbols of industrial precision.
Redundancy
Steam hammers were eventually made redundant with the introduction of
Tourist attraction
In 1969 the Creusot hammer was dismantled and reassembled in Le Creusot town square. Unfunctional, it serves as a tourist attraction and a reminder of a bygone era of technological achievement.
Footnotes
References
- ^ "Creusot Steam Hammer (1876)" (PDF). Landmarks. American Society of Mechanical Engineers. Retrieved 2019-06-20.
- ^ ASME. Archived from the original(PDF) on 2008-10-31. Retrieved 2009-01-18.
- The Largest Hammer in the World — The New York Times, January 13, 1878.