Flow Meters Products
Averaging Pitot Tubes
Pitot Tube Array
Custody Transfer
Mass
Circuit Balancing
Duct Air Flow
Open Channel
Oriface Plates
Thermal Dispersion
Turbine
Venturi
Ultrasonic - Gas / Liquid
Sanitary Mount
Air Velocity - Anemometers
Circuit Balancing
Custody Transfer
Duct Air Flow
Electronic Gas Mass Flow
Flow Meters
Magnetic Flowmeters
Magnetic Flowmeters
Mass
Mechanical Flow Switches
Open Channel
Orifice Plates
The most common and widely used differential pressure producers, suitable for a wide range of flow measurement applications in line sizes of 50 mm and above. Choose 'concentric square edged' for general application, 'conical entrance' or ’quarter circle' for low Reynolds number flows, and 'segmental' or 'eccentric' for flows containing light solids and slurries.
Based on proven technology orifice plates have no moving parts and are suitable for high temperature and pressure applications. Orifice plates are recommended for clean liquids, gases and low velocity steam flows.
Restriction orifice plates can be used as a simple pressure reducing device, or to limit flow rate in a pipeline. They are designed to slip between pipe flanges.
Flow Nozzles
For measurements where high temperatures and velocities are present, the flow nozzle may provide a better solution than an orifice plate. Its construction makes it substantially more rigid in these adverse conditions and flow coefficient data at high Reynolds numbers is better documented than for orifice plates. The inlet is contoured, and may be either radius entrance (ISA1932) or elliptical entrance (ASME long radius). The flow nozzle has about a 65% greater flow capacity than an orifice with the same diameter.
Venturi Tubes
There are two common types of Venturi tube - the Venturi nozzle, and the classical Venturi. Both feature a convergent inlet section and a divergent outlet section. The major advantage of the Venturi over orifice plates and flow nozzles is in the area of pressure recovery. Typically, unrecovered pressure is in the region of 10- 30% of measured DP as opposed to 40 • 90% for an orifice plate (depending on beta ratio). Although the cost of a Venturi can be comparatively high, where pumping costs are important the initial outlay can be justified.
Differential Pressure Gauges Assembly
Rototherm manufactures a range of high quality, cost effective and reliable differential pressure gauges designed to measure the difference in pressure between two points in a system and show it on a single dial gauge such as differential pressure across an orifice plate.
Flow Recorders
Utilising a high quality differential pressure unit, the Clearscan range of circular chart recorders includes options for measuring temperature and pressure as well as flow.