Sierra instruments are known for being robust and reliable, but is important to remember that even the most robust instruments, especially flow meters, can fall out of calibration and drift. Drifting of Sierra instruments can occur for many reasons, but flow meters are especially prone to drifting caused by their environmental surroundings. Corrosion and dirt are known to be the number one cause of flow meter calibration drift. Because it is not possible to control the environment in which you place a flow meter, it is of utter importance to ensure you are calibrating your flow meter regularly and properly. Proper calibration is needed to ensure accuracy and reliability.
To assist you in best practices for Sierra flow meter calibration, we have listed five best practices below.
MEETING CALIBRATION REQUIREMENTS
One best practice during Sierra flow meter calibration is to confirm that the standard you are using is accurate and meets all calibration requirements. A general rule of thumb to go by is that your standard should be 4x more definite the unit under test (UUT).
TRACEABILITY TO A RECOGNIZED STANDARD
During Sierra flow meter calibration, it is always important to establish traceability to the standard you chose to use for calibrations. By establishing traceability, you will be able to create an unbroken chain of documentation that shows exactly how the Sierra flow meter calibration compares to accurate standards. Traceability also validates flow meter accuracy and reliability after calibration.
Another best practice to keep in mind during Sierra flow meter calibration is that the rate of flow between the UUT and the standard must always be in a steady state. What this means is that the required standard flow rate and the UTT should be compared in real time during calibration to ensure that the system flow rate does not vary with time.
During Sierra flow meter calibration, it is vital to make sure that all media measured by the standard is also being measured concurrently by the flow meter. Specifically, it’s important to verify that there are not any leaks or substantial temperature changes that could affect the calibration of the Sierra instrument.
One of the easiest and most important best practices to follow during Sierra flow meter calibration is assuring you are performing calibrations under the correct conditions. This means that calibrations should be performed under conditions that are typical of a flow meters operation and the factors such as, viscosity, density and heat content of the media are being taken into consideration. Calibration should match closely with the flow meters actual application