Pressure Test

BlueTherm Pressure Test Guidelines

BlueTherm pipes undergo expansion when subjected to pressure, influenced by their material properties and the thermal expansion coefficient, which can cause a pressure change of 0.5 to 1 bar due to temperature variations between the pipe and the test medium. It is crucial to maintain a constant temperature of the test medium throughout the test, as specified in DIN 1988 TRWI standards. The pressure test should be conducted at 1.5 times the operating pressure.

To conduct the test:

1. Preparation:

   • Use cold water to slowly fill the pipe system and ensure it is completely bled using calibrated instruments capable of detecting pressure changes of 0.1 bar where possible. It is essential to measure pressure at the lowest point of the system.

2. Post-Welding Considerations:

   • Allow a minimum of two hours after the last welding operation before conducting the pressure test to ensure proper joint integrity.

3. Testing Procedure:

   • The pressure test consists of two stages:

     • First Stage: Apply a test pressure equal to the permissible working pressure plus 5 bar. This pressure should be applied twice within 30 minutes, with a 10-minute interval between applications. Monitor the pressure drop during each application. If the pressure drops by more than 0.6 bar within 30 minutes, at a rate of 0.1 bar per minute, this indicates a leakage.

     • Second Stage: Immediately after the first stage, maintain the test pressure for a minimum of 2 hours without interruption. Monitor the pressure drop during this period. If the pressure drops by more than 0.2 bar and there are signs of leakage in the pipework, corrective measures must be taken, and the test should be repeated.

These procedures ensure the integrity and reliability of BlueTherm piping systems under operational conditions, confirming their suitability for various applications.