How to Read Glass Tube Flow Meters
- 1). Connect the glass tube flow meter to a source of fluid flow (e.g., a garden hose).
- 2). Turn on the fluid flow source, and watch the float rise within the tube. Once the float has stabilized, record the value from the measurement scale. If you have a direct reading tube, the value you record is simply the fluid flow rate, in units specified by the measurement scale (e.g., liters per second).
- 3). If you have a reference scale tube, the measurement scale is in arbitrary units on a linear scale. In this case, calculate fluid flow rate using a reference scale flow correlation table, which is usually supplied by the manufacturer of the glass tube flow meter.
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