The present definition in the VIM, although being more exact, appears to lack a number of the clarity of the definition that is older, and thus the older option has been given for reference. The comparison in a Flow Meter Calibration is against a standard. The standard consists of the system of pumps, conduits, fluids, instrumentation, amount computations, benchmark measurement and operators. These combined supply a measure of the amount of fluid covering the apparatus or flow meter being calibrated.
The dimension of fluid flow is vibrant, and the states of use affect somehow all measurement devices. It’ll be impossible to really have a standard which completely replicates the conditions under which the meter will probably be utilized in practice. Flow devices are influenced by temperature, viscosity, flow profile, flow pulsations and rate changes. Not only that, they are influenced by the outside surroundings, pressure, vibration and temperature, etc. Distinct devices are influenced in various manners.
That recognized by the standard and since a calibration is a comparison between the measurements made by the apparatus under evaluation, the resultant relationship is going to be for the states that are given; so a further evaluation of the relevance of the last application should be carried out. Choosing the standard is a compromise to the best reproduces the states of use while providing an appropriate reference standard measurement. The standard must also be harmonious with features and the operation of the meter to be analyzed as well as the outcome required.
The extent to which the states of use affect a flow measurement device is commonly a function of the flow rate. Hence it is significant that calibration happens across a reach of flow rates to create this relationship.
Flow meter Recalibration Choices
End users who need to get their flow meters recalibrated have several options of where to send their meter:
- The flow meter maker;
- A cellular telephone service that does onsite calibrations.
- There are several highly reputable and well known Flow Meter Calibration facilities all over the world.
Likely the top such facility in America is Colorado Engineering and Experiment Station Inc. (CEESI), found in Nunn, Colorado and Garner, Iowa. Flow Dynamics, obtained by Badger Meter in 2010, runs a primary standard calibration facility in Scottsdale, Arizona.
VSL is the principal metrology lab for much of Europe besides doing flow calibrations. Its doors opened in March 2000 and specialize in the calibration of the high pressure gas flow meters.
Flow studies have identified more than 50 independent flow calibration facilities situated in distinct areas all over the world. With the global flow meter marketplace each year, growing, demand and the need for recalibration services might be anticipated to grow. Whenever a flow meter is sold, the odds are quite high that it will need to be recalibrated at some stage in the following three to seven years. Moreover, there’s an extremely large installed base of flow meters in the field that has to be recalibrated.