Hydrostatic Test Verification

A Hydrostatic Test Plan should contain the following information at a very minimum:

1. Approved Pressure Test Plan
2. Drawings of the system being tested
3. Location/layout of the test setup and test boundaries
4. Identification of all blank/blind flange locations if applicable
5. Drawing showing the exclusion zone with the location of “CAUTION” signage, barricades, or other controls for safety
6. Detail of the test setup - identify the pressure ratings of all components and pressure relief valves settings
7. H₂O pH and salinity measurements
8. Pressure gauges calibration sheets
9. Pressure gauges certification labels (current & up to date)
10. Detailed test procedure

Sigma verifies the completed and approved Hydrostatic Test Plan. Inspectors witness the following checks during the Hydrostatic Test:

1. Check Hydrostatic Test requirements
2. Check any liquid requirements such as H₂O pH or salinity
3. Check gauges and chart reader calibration and range in conjunction with the current hydrostatic test
4. Monitor gauges and chart reader while the vessel is brought up to pressure for current test requirements
5. Check the vessel for any leakage
6. Check all couplings, nozzles, and welds for any leakage
7. Review chart reader and gauges after prescribed test elapsed time
8. Ensure pressure did not drop from beginning test pressure
9. Denote any relevant ambient temperature deviations
10. Check vessel being relieved of all test pressure
11. Document and report any leaks and/or anomalies

Sigma provides Hydrostatic Test verification as part of the company’s core competency in Third-Party Verification (Vendor Surveillance) and QA/QC review/oversight.