Although regular flow meter calibration is necessary to ensure accuracy, some quality professionals struggle with when to calibrate a flow meter. Application, time in use, and maintenance schedules are a major factor in the performance a flow meter. The application includes whether the meter is measuring a gas or liquid, maximum flow rate, and the specified accuracy requirements. Time in use can indicate when a flow meter was initially installed and an estimate of operational hours. Following, or forgetting, preventative maintenance makes a large impact on flow meter accuracy and effectiveness.
Gradual and imperceptible changes occur in the meter due to environment, use, and other factors. Flow meters issues aren’t visible externally. To identify possible issues, the flow meter must be taken apart. This process will happen if issues are found during flow meter calibration testing.
Choosing Calibration Intervals
In general, the manufacturer recommendation is that new flow meters should have a six month calibration cycle. Flow meters that are used in unfamiliar applications are also recommended to have calibration after six months. As those calibrations are performed, you can analyze the results to adjust your schedule accordingly. Recommendations may differ by manufacturer. Check the flow meter manual, contact the manufacturer, or ask your ISO/IEC 17025 accredited calibration lab for help establishing calibration intervals. Flow meter calibration, repair, and maintenance should not interfere with work. To verify equipment reliability and keep operations running smoothly at the same time, consider the points below.
Flow Meter Calibration Tips
- Use an onsite calibration provider, especially if you have over 20 units
- Choose a calibration lab that can service all equipment
- Plan maintenance schedules, repairs, and calibration to include as many instruments as possible
- If your facility has annual shutdowns or slow periods, try to schedule calibration during that time
- Utilize pickup and delivery options if available