DOWESTON has compiled and written definitions for several industry terms. This list is intended to be a glossary to help you better understand elements of our i

DOWESTON has compiled and written definitions for several industry terms. This list is intended to be a glossary to help you better understand elements of our industry. Process instrumentation is used in a very wide variety of applications, wherever measurements are required for media that flow or are stored in containers or tanks. Many of these terms will help you understand the techniques used in such measurements.

Accuracy Insertion Meter Thermal Mass Flow Meter
Backpressure K-Factor Thermal Mass Flow Switch
Calorimetric Flow Meter Laminar Flow Turbulent Flow
Thermal Flow Switch Level Switch Turbine Flow Meter
Cavitation Level Transmitters Ultrasonic Flow Meters
Density Mass Flow Meter Universal Process Display
EMI/RFI Effects Open Channel Flow Meters Variable Area Flow Meters
Flow Meter Positive Displacement Flow Meter Velocity Flow Meter
Flow switch Process display Volume flow meter
Fluid Purge Flow Meter Wireless Monitoring
Full Bore Meter Reynolds Number Wireless Monitoring System
head tammy / rotometer
accuracy
The accuracy of the flow meter is the maximum positive and negative deviation between the indicated value of the meter and the true value of the flow rate or the total value of the flow. It is the interval between the actual value of the measured quantity and the stated probability. Accuracy can also be called uncertainty. Accuracy includes combined errors due to linearity, hysteria, and repeatability. Accuracy can be expressed as a percentage of span or full scale, as a percentage of rate, or as a percentage of cap or cap. It is important to understand the difference between the stated values.

back pressure
Back Pressure - Refers to pressure, not the desired flow of gas in a given pipe diameter. Any condition in which the pressure in the system is greater than the supply pressure. Back pressure is caused by blockages in the pipe, pipe orientation or orientation, pipe surface and pipe type, and tight bends. The term back pressure is misleading when pressure is maintained and causes flow in the same direction due to air resistance, friction between molecules, but reduces flow due to resistance. Backpressure is often confused with pressure drop. Back pressure assists the release of vapor in the liquid and is a function of the liquid piping system head. This condition is often called cavalry.

flow meter

Flow meters measure continuous flow by detecting thermal changes in the medium as it flows through the sensor. For reference, thermal flow meters are commonly used in air conditioning, dust collection, energy saving systems, potable/non-potable water, sulfuric acid, and ventilation monitoring.


Flow Switch
A flow switch that measures flow by detecting a thermal change in the medium as it flows through the sensor. Heat flow switches are used in chemical feed systems, cold water feeds, combustion cooling systems, damping regulators, for pump protection and ventilation.


Cavitation
If liquid enters the flowmeter at a pressure close to the vapor pressure, the pressure drop in the flowmeter will cause the liquid to gas. If, as the pressure recovers, the gas pressure rises above the vapor pressure again, the bubbles can burst, causing cavitation. Plating and vaccination can damage many piping systems and many types of flow meters.


Spend
The properties of a liquid are expressed as weight or mass per unit volume. Liquid density is generally a function of temperature. Gas and vapor densities vary with temperature and pressure. For example, water has a density of 62.34 pounds per cubic foot at 60o F. Density is 60.13 pounds per cubic foot at 200o

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EMI/RFI effects
EMI/RFI Effects - Electromagnetic Interference (EMI), also known as Radio Frequency Interference (RFI), occurs when a radio in the radio frequency spectrum is disturbed by external interference, either through electrostatic coupling or conduction, affecting circuits. Electromagnetic emissions can cause adverse reactions or degradation in the performance of electrical equipment. Commonly produced by welders, motor starters, VF drives, radios, causing analog instrument signal surges. Shielding and line filters can reduce these effects.


meter
Process instruments that measure the continuous flow of media through pipes or other vessels. The medium to be measured is usually gas, liquid or mud. There are many technologies available for flow measurement, some of which include thermal, mass, positive displacement, turbine, ultrasonic, and variable area/volume measurement. When there are particulates in the media, extreme high temperatures, high pressures, or in low flow applications, certain factors must be considered when selecting a flowmeter for the application.


Quantity switch
A process tool that measures the flow of a medium at a set point as it passes through a pipe or other vessel. The medium to be measured is usually gas, liquid or mud. There are many technologies used for flow switches, some of which include thermal, ultrasonic, and variable area/volume. When the media has particulate matter, extreme high temperature, high pressure, or is in a low flow application, certain factors must be considered when selecting the right flow switch for the application.


medium
Liquids are generally classified as liquids, gases or vapors. Liquids are practically incompressible and occupy a certain volume. Gases and vapors are compressible, filling any volume at a known or given pressure.


hole meter
Any flow meter that typically uses an entire flow team for flow measurement. Full bore gauges can include threaded or flanged process connections and typically have the same process connection size as a given pipe size.


Each flow meter uses energy to the system in the form of pressure or head. In addition to the meter, all fittings, valves and even straight pipe will affect the head to some extent. The flow meter introduces the system with as few heads as possible. Energy lost through friction causes resistance to flow, known as head


Inflow meter
Any flow meter that is inserted into a piping system, typically through a pipe insertion port or an isolation valve fabricated into a process piping system. An insertion flow meter is generally classified as any device that infers the overall flow rate based on a single measurement of fluid velocity at strategic locations within a pipe. A typical insertion gauge consists of a sensing element, a support structure attachment mount and a pressure seal. Used in measurements only, the accuracy of the meter is based on the assumption that there is a known relationship between the measured velocity and the average fluid or gas velocity.


factor
K Factor - The K factor of a flow meter is the ratio of the meter output in a pulse to the corresponding total amount of fluid passing through the meter during the measurement period. The change in K-factor can be presented as a function of Reynolds number or flow rate. Flow meter manufacturers can generate K-factor versus Reynolds number curves when the meter is calibrated on a fluid of convenience (usually water or air). The K-factor may vary with thermal effects on the instrument body or between piping schedules.

flow
La Minar Flow - A flow condition when a fluid flows in parallel layers with no breaks between layers. Laminar flow is the ideal flow condition for gas flow, when all the air molecules are moving together forward along the pipe. Efficient airflow systems should have a Reynolds number less than 2300.


don't switch
A process instrument that measures the point level of media in barrels, vessels, flues, tanks, wells, or other vessels. The medium to be measured is usually liquid, slurry or solid. Three common technologies for level switching include guided wave radar, non-contact ultrasonic and vibration. When the media has a low dielectric constant, is extremely hot, or is in the region of foam or steam, the proper level switching technology must be selected for accurate measurement and durability.


Do not launch
A process instrument for measuring the level of a continuum in a barrel, vessel, flue, tank, well, or other vessel. The medium to be measured is usually liquid, slurry or solid. Two common technologies for horizontal transmitters include non-contact ultrasonic and guided wave radar. When the media has a low dielectric constant, extreme heat, or is in the area of ​​foam or vapor, it is essential to select the proper horizontal transmitter technology for accurate measurement and durability.


flow meter
A flow meter that uses the Coriolis principle to measure, i.e. the mass of medium that passes through the meter in one unit of time. Mass flow meters typically have a higher cost and are very accurate compared to other meter technologies. Typical applications for mass flow meters include gases, industrial coatings, methanol/catalyst streams, and oils.


open channel flowmeter
A flow meter that measures the level of flow through a channel of known dimensions. Through the use of flues or flues, flow levels can be plugged into mathematical formulas to determine flow rates. Because of the way open channel flow meters measure flow rate, the meter itself consists of a level transmitter along with a process monitor that is able to convert from level to flow rate depending on other factors involved. Typical applications for open channel flow meters include sewage flow, gravity-fed sewer lines, stormwater monitoring, and clarifier flow. Waste and wastewater is a major industry for this type of flow meter.


Displacement flowmeter
A flow meter that measures the displacement of a gear or spur as media passes through the meter. This type of measurement uses the volumetric principle of measurement by counting gears or spurs as they move a known volume of media. These gauges maintain consistent accuracy despite changing viscosity conditions and are frequently installed in brake fluid, fuel, glue, grease, oil, polymer and Skydrol applications.


process display
Process tools that monitor and display process conditions. A process display can display its measurements by digital readout, scale, or other means. A process display with data input usually includes a means of outputting data, such as an analog loop output. Process displays come in a variety of configurations and it is important to choose a display that has all the features required by the application.
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chemical flow meter
A flow meter that measures flow to determine flow velocity. Volumetric flow meters are also commonly referred to as variable area flow meters, cyclic meters, and rotometers. A purge flow meter is a flow meter that meets the classic definition of a rotary meter, designed for low flow rates. The flow is through a gauge lift ball or other indicator which can be read directly on the scale inside the gauge. If the media contains particulate matter, it needs to be filtered. Typical purge flowmeter applications include measuring low flow liquids and gases including oxygen, nitrogen, air, helium, water, and deionized water.


Nods number
A dimensionless quantity for predicting flow patterns in liquid and gas flow systems. The Reynolds number is used to predict the transition from Laminar flow to turbulent conditions.
Turbulent and laminar flows can also be calculated, use the following formula to determine what is called
Reynolds number: re = vd/μ
Where:

And then there's the Reynolds number.
\ is the air density.
v is the average velocity.
d is the diameter of the pipe.
μ is the dynamic viscosity.


tammy / rotometer
See volume flow meter.


Mass flowmeter
Flow meters measure continuous flow by detecting thermal changes in the medium as it flows through the sensor. For reference, thermal mass flow meters are commonly used in air conditioning, dust collection, energy saving systems, potable/non-potable water, sulfuric acid, and ventilation monitoring.


mass flow switch
A flow switch that measures flow by detecting a thermal change in the medium as it flows through the sensor. Thermal mass flow switches are used in chemical feed systems, chiller feed water, combustion cooling systems, damping regulators, for pump protection and ventilation.


flow
A condition in which fluid flow undergoes irregular fluctuations in channels or layers. The velocity or velocity of a flow that moves in irregular magnitude and direction. Turbulent flow is the least efficient flow condition because air molecules spend so much energy bouncing off the pipe walls, forward, backward and sideways, that they expend so much energy moving away from the pipe.


Rotary Flow Meter
A flow meter that measures vane displacement as media passes through the meter. This type of measurement is based on velocity. In contrast to positive displacement meters (which count the gears or spurs to determine how much the media is moving), turbine meters measure flow rate based on the speed of the media through the meter. Turbine gauges are commonly used in abrasive and corrosive liquids because of their accuracy and mechanical integrity. Typical applications include chemical processing, coal bed methane applications, hydraulic applications, pesticide manufacturing, land reclamation and secondary oil recovery.


Sonic flowmeter
The flow meter calculates the flow rate of the medium as it is sent between the meter sensors via ultrasonic waves. Ultrasonic flow meters will average the transit time of the beam, or use the Doppler effect to measure frequency changes to determine flow velocity. An ultrasonic flow meter is non-invasive, which means it is installed outside the pipe. Since no entry is required, installing the meter requires no interruption of the process. Typical ultrasonic flowmeter applications are aerated liquids, dredging, plastics, pulp, sludge, slurries and sewage.


Show with process
Process displays for various monitoring process applications are available as standard factory configuration. Common process displays typically include communication interfaces such as RS-485 and/or Ethernet as well as outputs for controlling relays. "Universal" means that the device has more functionality built in than the standard process monitor.


Variable Area Flow Meter
See volume flow meter.


Degree flow meter
A flow meter, which measures the velocity or velocity of a given fluid or mass, usually in terms of fluid-interrupted volumetric flow rate through which the fluid opens.


Positive flow meter
A flow meter that measures flow to determine flow velocity. Volumetric flow meters are also commonly referred to as variable area flow meters, cyclic meters, and rotometers. In FLO-CORP's line we call our line of MEMFlo™ flow meters our volume line. MEMFlo flow meters use the volumetric principle of measurement to determine flow rate and offer greater capabilities than classic volume/variable area flow meters.
Our MEMFlo™ Plume Gauge line is extremely robust, available in all metals for high temperature and pressure, and capable of handling suspension in media
solid. Classic volume/variable area flow meters cannot handle particulate matter and require filtration of the media before it enters the flow meter. In addition, other meters use the principle of volume measurement, including positive displacement flow meters and gauges. Positive displacement meters count the gears or spurs to determine the known volume of media passing through the meter: Even though these meters use design volume measurements, the name refers to the way the media displaces the gears or spurs to determine the flow rate. Water flow meters typically rely on positive displacement (volume) or turbine (velocity) measurements.


line monitoring
Monitoring done without the use of wires between when data is reported by the device and when it is received by the interface. For example, cellular wireless devices report data wirelessly to cell towers. Then, view the reported process data through the web interface. In this example, wires might be used to connect a process measurement device to a cellular transmitter in the field, and the wires are used to move the data once it reaches the cell tower. Regardless, the process involves wireless monitoring, as field devices can report data at some stage in the process without using hardwired connections.
Wireless monitoring can use a variety of transmission methods, including bluetooth, wifi, cellular, satellite
Wait. Consider another example, a level launcher mounted on a tank truck. When pickups and/or deliveries are made, level transmitters periodically measure the tanker's level. At set intervals and/or trigger points, wireless monitoring devices report via cellular or satellite data. These data are then available through a web interface. Data is reported via wireless monitoring as long as the tank is in the battery coverage area or has unimpeded communication with the satellite. Once the data is reported, it can be viewed by logging into the web interface or the software interface. Additional functionality is also available through the interface, including wireless configuration reporting of the device, setting email/text alerts, GPS location (if the device is GPS capable), and other information.


line monitoring system
A device (or devices) that uses wireless communication to report process data measured by process instruments (flow meters, level transmitters, etc.). Serves as a part of the system to provide processing data, configuration functions and other functions through software or web interface. Wireless surveillance systems are a type of machine-to-machine (M2M) functionality. See Wireless Monitoring.