Bolt tensioners are devices designed to apply a specific tension to a bolt. The device may be either removed once the actual nut is threaded into place, or left in place, in the case of a hydraulic nut.
The metric system does away with all of the different units of volume used in the English system, and instead, uses only one unit to measure volume. That unit is called the liter. Materials Needed: Meter stick or metric ruler; stiff cardboard such as poster board; scissors or hobby knife; tape.
Conventionally, a spirometer is a device used to measure timed expired and inspired volumes, and from these we can calculate how effectively and how quickly the lungs can be emptied and filled. 1  The measurements that are usually made are as follows: