NRG Global Instruments

Metal Variable Area Type Flow Meter are designed to measure flow rate of liquids and gases under

critical conditions. It consists of a tapered metal tube, an indicating assembly and float. A magnet

encapsulated in float couples with rotating magnets are connected to an indicating pointer. Henceforth,

the movement of the float is accurately indicated in terms of flowrate.

They are intended for application where high pressure, temperature or corrosive conditions preclude

the use of conventional glass tube. These are all Metal Variable Area Type Flow meter design to measure

flow rate of Liquids & Gases under critical conditions. It consists of a tapered metal tube, an indicating

assembly and a float. A magnet encapsulates in float couples with rotating magnets connected to an

indicating pointer, thus the movement of the float, is accurately indicated in terms of flow rate.

 

2. Working Principle

When fluid or gas flows through a taper tube containing a float, a pressure difference of P1 and P2 is

created between upper and lower side of the float. The float moves upwards by a force obtained by

multiplying the pressure differential by the maximum cross-sectional area of the float.

Based on Bemoulli's theorem, the principle mentioned above can be theoretically expressed as

follows. Due to taper tube, as the float moves upwards, the fluid passing area increases as a result of which the

differential pressure decreases. Upward movement of float stops when the dead load is dynamically balanced by the differential pressure. Tapering of metering tube is so designed that the vertical movement of the float becomes linearly proportional to the rate of flow and the scale is provided to read the position of the float, thus

giving birth to flow rate indication.

 

3. Specifications

Accuracy : ± 2% of FSD

Rangeability : 10:1

Repeatability : ± 0.5%

Temperature Rating : -200 to 250°C

Pressure Rating : 40 Bar

Flow Direction : Bottom to Top

Connections : Flanged, TC End and Screwed

Enclosure : IP 65 Weatherproof

 4. Design features

1. Simplified piping and reduced space requirements

2. Permanent magnetic link between metering float and motion position transmitter

3. Precision swaged metering tube

4. Guide cartridges easily removable for cleaning

5. Provide with Electrical transmitter, flow indicator or alarm

6. Available F/F Height in 350, 450, 500 mm

7. Available Flange size 15 NB to 150 NB & Flow 200 LPH to 50,000 LPH

Additional Information:

• Delivery Time: week
• Packaging Details: corugated box

NRG GLOBAL INSTRUMENTS Make Metal tube Rotameters are variable area flowmeters for measuring volumetric flow rates of liquids and Gases. The construction includes a tapered stainless-steel tube. A float with a magnet embedded in it, moves inside a tapered tube. The float is magnetically coupled with an indicating pointer assembly.

Additional Information:

• Production Capacity: 100
• Delivery Time: week
• Packaging Details: export worthy packing