A Variable Area Flow Meter (Rotameter) is a reliable and cost-effective instrument used for measuring the flow rate of liquids, gases, and steam in various industrial processes. It operates on the principle of a float moving freely within a tapered tube, where the position of the float indicates the flow rate. As the flow increases, the float rises, creating a larger flow area and maintaining a constant pressure differential across the float.
Known for its simple design, high accuracy, and ease of installation, Variable Area Flow Meters are widely used in chemical processing, pharmaceuticals, water treatment, food & beverage, oil & gas, and other industrial applications. They provide direct flow indication without requiring an external power source, making them an efficient solution for continuous flow monitoring.
Available in metal tube and glass tube designs, these flow meters can be customized for various flow ranges, pressures, temperatures, and process media to meet specific application requirements.
Applications of Variable Area Flow Meter
- Chemical and Petrochemical Industries
- Pharmaceutical Manufacturing
- Water and Wastewater Treatment Plants
- Food & Beverage Processing
- Oil & Gas Industries
- Power Generation Plants
- HVAC Systems
- Process and Utility Lines
Features of Variable Area Flow Meter
- Direct and easy-to-read flow indication
- Suitable for liquids, gases, and steam
- No external power supply required
- Low pressure drop across the meter
- High measurement accuracy and repeatability
- Rugged construction for industrial environments
- Available with local indication and transmitter output
- Wide range of materials and connection options
Available Options
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Glass Tube Rotameters
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Metal Tube Variable Area Flow Meters
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Magnetic Coupled Indicator Models
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Flow Switch Integration
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Transmitter with 4–20 mA Output
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Explosion-Proof Versions
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PTFE-Lined Construction for Corrosive Media
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Customized Flow Ranges and Scales
Specifications
| Parameter | Details |
|---|---|
| Product Name | Variable Area Flow Meter (Rotameter) |
| Measuring Principle | Variable Area / Float Type |
| Size Range | 15 NB to 150 NB (½" to 6") |
| Measuring Media | Liquids, Gases, Steam |
| Tube Material | Borosilicate Glass / Stainless Steel |
| Body Material | SS 304, SS 316, SS 316L, Carbon Steel, PP, PVC |
| Float Material | SS 316, PTFE, Hastelloy, Titanium |
| Connection Type | Flanged, Threaded, Tri-Clamp, Screwed |
| Accuracy | ±1.0% to ±2.0% of Full Scale |
| Repeatability | ±0.5% of Reading |
| Operating Pressure | Up to 40 Bar (Model Dependent) |
| Operating Temperature | Up to 250°C (Model Dependent) |
| Scale Type | Direct Reading / Customized Scale |
| Output Signal (Optional) | 4–20 mA, HART, Pulse Output |
| Protection Class | IP65 / IP67 (for transmitter models) |
| Mounting Position | Vertical Installation |
| Compliance | ISO, ASME, DIN Standards |
Benefits
Variable Area Flow Meters offer a dependable solution for accurate flow measurement and process monitoring. Their simple operating principle, low maintenance requirements, and ability to function without external power make them ideal for a wide range of industrial applications. With excellent visibility, durability, and versatility, these flow meters help improve process efficiency, quality control, and operational reliability.