As highlighted in Pumps & Systems’ article, “Hydrostatic Testing for Rubber Expansion Joints,” hydrostatic testing is an essential procedure for ensuring the integrity and safety of piping systems. Expansion joints, vital components that compensate for thermal movement and vibration, must undergo rigorous testing as outlined by industry standards.

What is Hydrostatic Testing?
Hydrostatic testing involves using pressurized water to verify a piping system’s strength and check for leaks. This critical step is performed before production startup or after scheduled maintenance to ensure system reliability. By testing at 150% of the system design pressure for at least 10 minutes, operators can identify and address potential vulnerabilities, avoiding costly downtime.

ASME Standards for Hydrostatic Testing:
The American Society of Mechanical Engineers (ASME) provides detailed guidelines for hydrostatic testing in its B31 codes:

• ASME B31.1 (Power Piping): Covers systems in power plants, requiring a minimum test pressure of 150% of design pressure. For unrestrained expansion joints, temporary restraints or isolation methods must be used to prevent damage.
• ASME B31.3 (Process Piping): Applies to industries like petrochemical, pharmaceutical, and textiles. Expansion joints in these systems require anchors and control rods capable of withstanding the hydrostatic test pressure.

Key Considerations for Expansion Joints:

1. Restrained vs. Unrestrained:
   • Restrained joints have control rods to contain pressure thrust forces during testing.
   • Unrestrained joints require external measures, like anchors or temporary restraints, to manage thrust forces.
2. Testing Alternatives:
   If running the test with the expansion joint is impractical, operators can either isolate the joint or test it separately under controlled conditions.
3. Safety and Durability:
   Ensuring the integrity of expansion joints during testing is critical to the overall performance of the piping system.

Click here to learn more about Meccom Industrial Products’ custom expansion joints.

Article with all rights reserved, courtesy of pumpsandsystems.com.