Flow Meters

About Flow Meters and Flow Meter Distributors Including: Air Flow Meters, Coriolis Flow Meters, Electromagnetic Flowmeters, Flow Indicators, Flow Switches, Flowmeters, Peak Flow Meters, Rotometers, Ultrasonic Flow Meters, Water Flow Meters, Fuel Flow Meters & Vortex Flow Meters.

Flow meters are used to measure the flow of air, fluids and gas. Some of the most popular flow meters are: peak flow meters, water flow meters, fuel flow meters, air flow meters, ultrasonic flow meters and flow monitor services. Many flow meters measure the volume of the material while other flow meters measure the speed, and still other flow meters measure the mass of the materials. For the most part, flowmeters are used to infer mass flow through calculations that flow meters and flow monitor instruments make after taking various flow measurements, such as absolute pressure, differential pressure, viscosity and temperature. Most flow meters are made of three parts: the primary device, transducer and transmitter. These three flow meters parts are usually combined so that the flow meter is one complete instrument. Flow switches, however, typically have a fourth component that serves as a switching unit to control flow. Flow indicators, which are observation windows in industrial processing lines, aid in measuring flow by visual indicators.

Flow meter distributors manufacture various instruments for different measurements of flow. Thermal mass flow meters take measurements with two sensors that work together. A temperature sensor reference and an active heated sensor take measurements by calculating how much heat loss occurs in the flowing liquid, and thus these flow meters can determine the flow rate based on this amount. Another type of flow meter is the Coriolis flow meter, which operates on the basis of the Coriolis Effect. In the Coriolis Effect, an excitation force is applied to the flow meter tube, causing the fluid or gas to rotate because the acceleration is acting in opposite directions on both sides of the applied force. A flow meter measurement can then be taken. Other kinds of flow meters operate using sound: These are called ultrasonic flow meters, and include several types, like Doppler Effect flow meters and time-of-flight flow meters. Another type of flow meter is an electromagnetic flowmeter, which is a type of volumetric flow meter that functions based on Faraday's law of electromagnetic induction. Also, there are rotometers, which utilize a rotating float that moves vertically through a tapered tube.

Flow meters are useful in a variety of fields. Medically, flow meters are used to measure a patient's air intake. These types of flow meters are called peak flow meters and are particularly beneficial for asthma patients. In plumbing, water flow meters are used to measure the amount of fluid running through a tube for efficiency purposes. In general, flow meters are used in many industrial purposes for flow measurements to help companies determine profit gain or loss. Other industries that benefit from the use of flow meters, peak flow meters, fuel flow meters, water flow meters and flow monitor services include automotive, petroleum and gas, utility services, HVAC, food processing and raw materials.

Each type of flow meter has specific guidelines that must be followed for proper use. For example, when using gas flow meters, the flow meters must remain full of gas. Liquid in gas flow meters can affect the flow meter's accuracy. Similarly, in order for liquid flow meters to work properly, they must remain full of liquid. Gas in liquid flow meters can affect the accuracy of flow meters' readings. Generally, contaminants of any kind will cause an inaccurate reading of flow meters, so flow meter distributors advise that flow meters and flow monitor instruments must be treated with care and cleaned regularly.

Smart-Trak Mass Flow Meters	Innova-Vortex Mass Flow Meters
Flow Meters and Flow Meter Distributors Images Provided by Sierra Instruments

Flow Meters and Flow Meter Distributors Image Provided by Kobold Instruments, Inc.

Flow Meter Types

• Air flow meters are used to measure the flow of air.
• Coriolis flow meters are used to measure the force of acceleration resulting from a moving object towards or away from the center of rotation.
  
• Differential pressure flow meters are used to measure the flow of fluids and gases in a pipe by introducing constriction that causes the pressure to drop. The pipe must be clean to result in accurate measurements.
• Fuel flow meters are ultrasonic, turbine or positive displacement flow meters which measure fuel usage rate and remaining fuel quantities in transportation devices and stationary pumps.
• Insertion flow meters measure flow at one position in a pipe, and then, based on the measurement, they estimate the flow rate for the entire pipe.
  
• Electromagnetic flowmeters measure by creating a magnetic field that is channeled into the liquid and causes a voltage signal to be sensed that is proportional to the flow of liquid.
• Flow switches are used to monitor fluid or gas flow while it is passing through its valve body, then to send an electrical control sign if the flow rate is too high or too low. 
• Flowmeters are used to measure the flow of air, fluids and gases.
• Mass flow meters are used to measure gas flow and are one of the more popular flow meters. This meter is relatively unaffected by changes in temperature or pressure in the tube or pipe.
  
• Open channel flow meters are used to measure the flow of liquids when they are open to the atmosphere.
  
• Peak flow meters are used by patients with asthma or other lung disorders to measure the amount of air patients take into their lungs. These flow meters allow physicians to determine the severity of the illness.
  
• Positive displacement flow meters trap liquid to measure its flow by rotating parts that move between seals and the meter body.
  
• Rotometers have a rotating float that moves vertically through a tapered tube.
• Sight flow indicators allow the operator to view the liquid as it is moving. Some models come equipped with lights to enhance the visibility of the fluids.
  
• Target flow meters measure the amount of force that is exerted on a target in a particular liquid or gas. This should not be used to measure high viscosity liquids because the target can be damaged.
  
• Thermal flow meters are meters that use thermal properties of fluids to measure the flow. The meter is heated and as the liquid flows by, it can tell the flow rate by the amount of heat lost.
  
• Turbine flow meters consist of a rotor that measures the fluid when it passes through the blades. The blade speed is translated into the speed of the fluid
  
• Ultrasonic flow meters use sound to determine flow rate. Both Doppler Effect meters and time-of-flight meters are different kinds of this type.
  
• Variable area flow meters measure by letting the flow stream change the opening in the meter with a movement of an internal part.
  
• Vortex flow meters calculate flow rate by measuring the differential pressure of vortices created downstream from a partial obstruction, or "bluff body"; they are highly resistant to vibration and are often used in harsh environments.
• Water flow meters are flow meters designed for measuring flow rates of water in various channels, tubes, partially filled pipes, streams, and rivers.

Flow Meter Terms

Absolute Pressure - Atmospheric pressure plus gage pressure in flow meters.

Accumulator - Area where fluid is under pressure and stored as a source of power within flow meters.

Bluff body - An obstruction, often wedge-shaped, placed in the middle of a gaseous or liquid flow designed to create a downstream vortex in vortex flow meters as a means of measuring flow rate.

Control Point - The temperature flowmeter instruments need to maintain to perform designated functions of flow meters.

Coriolis Force - The force that occurs when a mass has a velocity moving outward in a rotating plane of flow meters.

Counter Weight - A mass that is added to a particular substance to create a more balanced and stable apparatus for flow meters.

Current - The flow rate of electricity within flow meters.

Density - A substance's mass per unit of volume in flow meters.

Flow - The travel of materials in response to a force, such as pressure within flow meters.

Flow Nozzle - A constriction made of a contoured plate that forms a hole in flow meters for the flow stream so a flowmeter measurement can be taken.

Flow Rate - The velocity of flow in flow meters.

Head-Loss - The loss of pressure in flow meters or a flowmeter system that is measured with a length parameter (such as amount).

Hot-Tap - Allows for flow meters to be inserted or removed without causing a complete system shutdown.

Integrator/Totalizer - A flow meters device that measures the total flow of fluids.

Manometer - Measures fluid pressure. This is a U-shaped flowmeter tube containing liquid which adjusts with the pressure in the flowmeter tube.

Mass Flow Rate - The volumetric flow rate of a liquid or gas times its density, expressed as pounds per hour or kilograms per minute in flow meters.

Potential Energy - The potential of energy when a liquid is in a position or height above a flowmeter place to which it can potentially flow.

Transducer - The part of flow meters that sense fluid as it passes through the flowmeter device.

Transmitter - The part of flow meters that produce the usable flowmeter information from the transducer of flow meters.

Weldolet - A connection for a metal pipe that is used to aid as a fitting for insertion-type sensors or flow meters.