Wednesday, November 18, 2009

Industrial Blacksmithing at the Library of Congress

The Library of Congress has the world’s largest collection of primary documents, including videos and films, to tell us about the past. Here is a link to a video filmed in 1904 at the Westinghouse factory.

They were creating a massive turbine and generator. I wonder if it was for the power house at Niagara Falls, N.Y.?

The men are doing an amazing job. They are in the process of turning an iron bar into a round ring with a circumference of 16 to 20 feet. The bar they are forging into a ring appears to be about 3 inches thick and about 12 inches deep. It must weigh several tons. In the first 2 minutes of the film they are hammering together a scarph where the two ends of the hot bar overlap. The 4 men with sledgehammers are making the initial weld using only muscle power. At the bottom right corner of the picture frame there should be a clock counting elapsed time. Watch at the 1:30 point when 3 men are striking with sledge hammers and a fourth man jumps in to hammer in time on the work.

At the 2:20 point a man, possibly the head blacksmith, jumps inside the hot ring to operate the chainfalls! The ring still has a section several feet long that is over 1600 degrees Fahrenheit. He guides the effort to push the ring back into the fire and then starts lowering the chainfalls. Watch again at the 2:55 point when he is hoisting the multi-ton ring out of the fire with the chainfalls. Watch his arms. He has a blacksmith’s build, with forearms bulging as large as his biceps. Then the men push and pull it on the chain falls to the next working station.

Then the ring goes to the steam hammer! At 3:15 it is being struck by the steam hammer. That machine uses a steam piston much like the one in a locomotive to raise and slam a 500lb. hammer head into the ring once each second. The steam hammer is being used to finish the weld and forge the ring down to an even thickness. That causes a bulge in the width of the ring. A man places a cutting tool called a hack under the hammer at 3:52 to cut off the excess metal and return the ring to the needed dimension.

What details are hidden in the larger film? There is a special type of anvil called a bridge anvil in the shot at 1:17. It probably weighs more than 300lbs. and is used for large industrial work like this. Finally the ring goes back to the anvil at 4:25 for finishing by hand held hammers and tools. At 4:46 they throw a thin plate of steel onto the weld and then hammer it into place. At 5:52 they are using sledges to strike a tool called a Flatter to smooth the outside edge of the ring.
What an amazing job. Surviving films like these provide a window onto daily life in another time.


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