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A Million Pounds In Action
If you’re curious what lifting a million pounds of steel looks like, here’s your chance to see – and hear – it.
NIST’s Million Pounds-Force Deadweight Machine creates extremely large forces, which NIST staff use to calibrate customers’ force sensors. This video shows NIST staff performing an actual calibration with the machine.
A three-story stack of stainless steel disks hangs from the customer’s sensor. At first, the stack of weights sits on the floor. But as the machine slowly rises, it lifts the weights one by one, in a chain. Each time a weight is lifted, the force sensor gets another 50,000 pounds’ worth of steel pulling down on it.
This process is extremely slow and delicate – so slow that the motion is almost imperceptible if you watch it in real time. When the recording is sped up, however, you may notice a ripple of movement as the weight stack rises and falls.