Variable Area Flowmeters
A variable area flowmeter, also known as a rotameter, is a type of flow measurement device, used for measuring the flow rates of different fluids, such as liquids, gases, vapor, and so on, in industrial settings. The volumetric flow of a fluid can easily be measured using these flow meters. It consists of a vertical tapered tube with a float inside that moves vertically in response to the fluid flow. They are often utilized in processes such as water treatment, chemical dosing, HVAC systems, and laboratory experiments.
At Cannon Water Technology, we offer various types of variable area flowmeters from reputed manufacturers like Blue White. The flow meters listed here are specially designed to serve challenging industrial environments and measure the flow rates of fluids with different consistencies and textures, including semi-solids, liquids, particulate fluids, slurries, and so on.
Our competitive prices, world-class customer service, ready-to-ship inventory, and quick turnaround times make us a trusted source for all your flow measurement needs!
How Does a Variable Area Flow Meter Work?
These flow meters feature a conical tube with a float inside it. The fluid flows through the tapered tube and forces the float to position itself such that sufficient area is left for the fluid to pass. This float will rise high when the flow increases. When used to measure the flow rate of liquids, the float rises due to the liquid’s buoyancy and its velocity head. When used for measuring gas flow, this buoyancy can be neglected, and float raises in response to the velocity head. The float of the flow meter moves proportionately to the flow rate of the fluid and the annular area between the tube wall and the float. There comes the point when the upward force of the flowing fluid and gravitational force exerted by the float’s weight downwards equalize. The float will remain constant in this position and won’t move up or down. The flow meter assumes a distinct position with every continuous flow rate. The position of the float will change according to gravity. The flow meters feature in-line floats, but they may also feature pistons or vane. The flow meters must be oriented and mounted vertically to the device for appropriate results. The changed position of the float indicates the flow rate of the fluid under consideration.
What are the Components of Variable Area Flowmeters?
Variable area flow meters consist of several key components that work together to measure and indicate the flow rate of fluids. The main components of a variable area flowmeter are:
- Tapered Tube: The flowmeter features a transparent or translucent tapered tube through which the fluid flows. The tube has a larger diameter at the bottom and a smaller diameter at the top, creating a pressure differential.
- Float: Inside the tapered tube, there is a float or piston that moves vertically in response to the fluid flow. The float is typically cone-shaped or spherical and is buoyant in the fluid.
- Guided Rod: A guided rod or guide wire is attached to the float and helps maintain its vertical alignment within the tube, preventing it from tilting or getting stuck.
- Scale: Alongside the tapered tube, there is a graduated scale that provides a visual indication of the flow rate. The scale is marked in units such as liters per minute (L/min) or cubic feet per hour (CFH), corresponding to the flow rate.
- Float Position Indicator: Some variable area flowmeters have a float position indicator, such as a magnetic or mechanical pointer, that moves in tandem with the float inside the tube. This provides an additional visual indication of the float position and the corresponding flow rate.
- Inlet and Outlet Connections: The flowmeter has inlet and outlet connections where the fluid enters and exits the device. These connections are usually designed to match the plumbing or piping system being used.
- Mounting Options: Variable area flowmeters may come with various mounting options, such as panel mount, wall mount, or pipe mount, to suit different installation requirements.
Beneficial Features of Variable Area Flowmeters
Our flow meters are popular due to their following beneficial features:
- Many variable area flow meter models feature a linear scale that has an extended measurement range and low-pressure drop.
- These flow meters are made up of high-quality material that makes them ideal for direct sunlight applications.
- We offer a wide range of variable area flowmeters for different types of fluids, including corrosive liquid flow measurement.
- Made of Hastelloy and sturdy materials, our flow meters are proven to assure several years of performance before they are taken out of service.
Applications of Variable Area Flowmeters
Variable area flow meters are used:
- For liquid and gas measurement
- As process analyzers
- For chemical injection
- For measuring high-pressure flow on offshore oil platforms
- For purging liquid or gas metering
We regularly supply these variable area flowmeters to our clients across the following industries
- Chemical and Petrochemical
- Food and Beverages
- Water and Waste Water Management
At Cannon Water, we make sure that we offer you the best and most high-quality products for all your water treatment needs. Quality is our topmost priority, and hence we source our products from trusted manufacturers. These products are carefully chosen and included in our list after much consideration.
Our experts watch industry trends and are aware of the changing customer needs, which makes us offer only the best and most in-demand devices through our website. These flow meters are often combined with other flow meters and water treatment devices for the best results in many process industries. If you have any questions regarding our variable area flowmeters, please feel free to contact us. Our customer support team will be happy to assist you.
- What is variable area flow meter?
The Variable area flowmeter is an instrument for measuring the flow of liquids and gases in pipelines.
- What is the advantage of variable area meter?
Variable area flowmeters offer several advantages like simple and visual flow indication, wide flow range, compatibility with different fluids, minimal pressure drop, reliability and low maintenance that make them suitable for certain applications.
- How to Select a Variable Area Flow Meter?
Selecting a variable area flowmeter involves considering several factors such as fluid and its properties, flow range, desired accuracy, assess environmental conditions, installation requirements to ensure the appropriate choice for your application.
- What is the accuracy of a variable flow meter?
The typical accuracy of a variable area flow meter is within the range of ±2% to ±5% of the full scale. This means that the measured flow rate can deviate by up to ±2% to ±5% from the actual flow rate.
- What is the range of variable area flow meter?
Variable area flow meters are available in various sizes, ranging from small meters suitable for low flow rates to larger meters capable of handling higher flow rates. The range of flow rates covered by variable area flow meters can span from a few milliliters per minute (mL/min) to several hundred liters per minute (L/min).