Abstract
- Variable area flowmeters (rotameters) measure fluid flow using a float balanced by buoyancy, drag, and gravity. Accuracy is affected by installation, float material density, and design.
- Flow is read by aligning the eye parallel to the float's reading point.
- LORRIC's dual-pointer design enhances visibility and precision, allowing for easy flow range definition and control within specific limits.
1. Operating Principle Behind Rotameter (variable area flowmeters)
- The flow rate is measured by the changing cross-sectional area of the pipe from bottom to top, using the balance achieved between the buoyancy of the float, the pull and thrust of the liquid, and gravity. This principle allows for the accurate determination of flow rates within the system.
- The variable area flow meters should be installed vertically.
- Because of buoyancy, the force of the liquid and the float material should be considered.
- The machining quality and float design will affect balance position.
- There is an accuracy difference between the variable area flow meter with and without the guide rod. The model with a guide rod is more accurate because the guide rod makes the float always stay in the axis of the flow meter. In contrast, the float without the guide rod will shift off-axis which could impact flow rate accuracy. Therefore, the accuracy in-part is dependent on the guide rod.
- Low price, no brand flow meters or product knock-offs have crooked guide rod problems because of bad design and machining. It results in inaccurate flow rates.
- The body of LORRIC variable area flow meters are made by injection molding with polymer which features high accuracy and low tolerance. In stark contrast to glass material.
- Each of LORRIC’s variable area flow meters is made through delicate machining with careful adjustments to detail. Our variable area flow meter is also customizable for certain specs depending on clients needs.
- If there is no obvious damage to the flow meter, any abnormality, such as drastic shifting of the float or unstable flow rates could be caused by piping issues.
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2. THREE advantages of variable area flow meter
- It is easier to read the flow rate by eye visualization.
- You can observe the status of the fluid through the transparent tube.
- It is an easy and quick way to receive flow rate data.
3. How to Read Flow Rate through the Float
Refer to the diagram above for types of floats and the following are reading methods:
- When reading the flow rate, ensure your eyes are level with the reading point.
- Use the correct reading position for the flow meter float (rotor) you ordered, with the horizontal black line in the diagram indicating the correct flow rate reading point for various types of flow meter floats (rotors).
- For a summary of reading methods, see the article on key points for reading flow meter floats (rotors).
4. Patent Dual-Pointer Design for Easy Flow Range Definition
LORRIC develops products with a user-centric approach, improving traditional methods of defining flow ranges with adhesive labels. The dual pointer design allows users to easily set flow ranges or fixed flow rates with a simple finger tap, ensuring clear visibility and reducing the risk of damage. Additionally, LORRIC's variable area flowmeters feature laser-engraved scales that are precisely tested and calibrated for each individual meter, ensuring accurate measurements specific to each device.
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LORRIC rotameters (area flowmeters)