Nutating Disc Liquid Flow Meters

Description

Nutating Disc Liquid Flow Meters are devices used to measure the flow rate of a liquid. They operate by utilizing a disc that moves within a chamber, allowing for the precise measurement of the volume of liquid passing through the meter.

Working Principle

The working principle of a nutating disc flow meter involves the movement of a disc within a measuring chamber. As liquid flows through the meter, it causes the disc to nutate, or wobble, on its axis. This motion is transmitted via a drive magnet to a follower magnet, which is connected to a register gear train. The gear train converts the disc's nutations into volume totalization units, which can be displayed for local readout or provided as an output for remote monitoring . This design is particularly useful because it allows for accurate measurement of liquid flow without requiring external power sources .

Applications

Nutating disc flow meters are commonly used in hydronic heating and cooling systems to monitor water usage and check for leaks . They are also suitable for measuring non-abrasive fluids, including high-viscosity liquids such as heating oils, lubrication oils, polymer additives, and ink .

Advantages over other Liquid Flow Meters

One of the main advantages of nutating disc flow meters is their ability to handle high-viscosity fluids with high accuracy, up to +/- 0.1 percent of full scale, and a rangeability of 70:1 or better . They do not require power, making them suitable for applications where power availability is a concern .

Limitations

Nutating disc flow meters cannot handle solids, entrapped air in liquids, or entrained liquids in gases . Additionally, they require specific inlet and outlet sections and a minimum Reynolds number for accurate operation .

Considerations

When considering nutating disc flow meters, it is important to evaluate initial costs, operating expenses, and maintenance requirements. These meters are generally durable and provide accurate measurements, but they may require regular maintenance to ensure optimal performance. Replacement and maintenance costs should be factored into the overall cost of ownership.