Pressure Gauge Calibration: What Every Plant Engineer Should Know
Pressure gauges drift more often than plant engineers expect. Here is what calibration actually checks, common causes of drift, and how to read a certificate.
Pressure gauges look simple, but they are among the most frequently mis-calibrated instruments we see in the field, often because of how they are handled rather than a fault in the gauge itself.
What Calibration Actually Checks
A pressure gauge calibration compares the gauge’s reading against a traceable reference standard across several points spanning its range, typically including zero, mid-scale and near full-scale, recording both as-found and as-left values.
Common Causes of Drift
- Pressure spikes or water hammer in the line
- Vibration from nearby pumps or compressors
- Corrosive or high-temperature process media affecting the internal mechanism
- Physical shock during installation or maintenance
Reading the Certificate
A proper certificate shows readings at multiple points, not just one, along with the stated uncertainty and a clear pass or fail against your required tolerance. If a certificate only shows a single point or no uncertainty figure, it is not giving you the full picture of the gauge’s actual accuracy across its range.
A Practical Tip
Gauges on safety-critical lines (boilers, pressure vessels, relief systems) deserve tighter intervals than general process gauges. If a gauge repeatedly comes back out of tolerance, replacing it is usually cheaper than continuing to certify and monitor a failing unit.
Our pressure and vacuum calibration covers gauges up to 1000 bar, transmitters, transducers and safety valves. See the full parameter list and ranges for details.
Need this done in your plant? ION Engineering is an ISO/IEC 17025:2017 accredited calibration laboratory serving industry across Bangladesh. Request a quotation or call +88 01713 588601.