According to EN 13480-5:2017, the hydrostatic test is the final integrity check for a piping system before commissioning. The standard requires that the test pressure be at least 1.43 times the design pressure for carbon steel, with a hold time sufficient for visual inspection of all joints.
During planning, the test pack must isolate all flanged connections, valve seats, and instruments not rated for the test pressure. Temporary blinds or blank flanges are inserted at boundary points. A calibrated pressure gauge with a range not exceeding 2x the test pressure must be installed at the highest point of the system.
Key acceptance criteria include:
• No visible leakage at any weld, flange, or threaded connection.
• No permanent deformation of pipe or components after pressure relief.
• Pressure drop not exceeding 2% of test pressure during the hold period, corrected for temperature.
The test record should document the test pressure, hold time, ambient temperature, and any repairs performed. A successful hydrotest validates both the weld quality and the design assumptions.
How do you handle test pack boundary isolation on your projects?
Source: EN 13480-5, 2017