Practical Considerations in Production Environments
Accurate pressure calibration is essential for reliable process control, product quality and regulatory compliance. While the underlying measurement principles are well established, performing pressure calibration in practice—particularly in production environments—introduces a range of operational challenges.
This article outlines common challenges encountered during pressure calibration of gauges and transmitters in industrial and pharmaceutical settings, with focus on practical execution rather than calibration theory.
Calibration Outside the Laboratory
Pressure calibration has traditionally been performed in controlled laboratory environments, where temperature, setup and stabilisation conditions can be carefully managed.
In production environments, these conditions are rarely available. Instruments are often installed in locations that are difficult to access, exposed to process conditions and integrated into systems that cannot easily be taken out of operation. As a result, calibration frequently requires removal of instruments from the process and transport to a laboratory, introducing additional handling, logistics and downtime.
Time Consumption and Operational Impact
Pressure calibration is inherently time-consuming, particularly when multiple measurement points, ascending and descending sequences and repetitions are required.
In practice, the total time spent on calibration includes not only the measurement itself, but also preparation, transport, setup and reinstallation. For production facilities, this can result in extended downtime or postponed calibration activities, especially when calibration must be coordinated with maintenance windows or production schedules.
Stabilisation and Control of Pressure
Achieving stable pressure conditions is a critical requirement for reliable calibration results. Each pressure point must be approached carefully and allowed sufficient time to stabilise before measurements are recorded.
In real-world installations, stabilisation can be affected by factors such as system volume, leakage, temperature variations and the dynamic behaviour of the pressure source. Overshooting or undershooting setpoints can further increase stabilisation time and introduce variability between calibration runs.
Operator Dependency
Many aspects of pressure calibration depend on operator judgement and experience. This includes how pressure is applied, how long stabilisation is allowed and how calibration sequences are executed.
Variations in handling or timing can influence repeatability and increase measurement uncertainty, particularly when calibrations are performed by different technicians or across multiple sites. Ensuring consistent execution therefore places high demands on training, procedures and documentation.
Handling, Transport and Reinstallation
When pressure instruments are removed from the production line for calibration, additional risks are introduced. Handling and transport increase the likelihood of mechanical damage, contamination or changes to installation conditions.
After calibration, instruments must be reinstalled and verified in the process, adding further steps and increasing the overall effort required. These activities contribute to the total calibration workload and may affect confidence in the final measurement result.
Documentation and Compliance Requirements
Pressure calibration in regulated industries must be fully documented and traceable. Managing documentation across multiple calibration activities, locations and instruments can be challenging, particularly when calibration is performed outside standard laboratory environments.
Incomplete or inconsistent documentation increases the risk of audit findings and deviations, placing additional pressure on quality and validation teams.
Summary
Pressure calibration in production environments involves more than applying a reference pressure and recording results. Practical challenges related to time consumption, stabilisation, operator dependency, handling and documentation must be carefully managed to ensure reliable and repeatable calibration outcomes.
Understanding these challenges is essential when planning calibration activities and selecting appropriate calibration approaches for instruments installed in active production systems.
One commonly used reference method for pressure calibration is manual deadweight calibration. Read more about its principles and practical limitations.(Artikel om manual deadweight)
In production environments, alternative calibration approaches are often considered to address these challenges. Learn more about on-site pressure calibration approaches.(Insacal pressure)