The Capabilities of Expansion Joints

Expansion joints play a crucial role in ensuring the safety and reliability of piping systems. Performance expansion joints offer excellent spring rates and movements, high-quality designs, and materials that are rigorously tested to provide peace of mind for end users. These joints are versatile, reducing inventory and simplifying decisions about which joint to use. They are rated for full vacuum on the suction side and pressure ratings on the discharge side of a pump. Validation testing ensures these are among the safest and most reliable expansion joints available.

Why Validation Testing Is Critical

There are three key areas where functional testing is essential for validating an expansion joint’s design for specific end uses: thermal movement, vibration isolation, and equipment settling.

  • Thermal Movements
    Pipes expand and contract with temperature changes, stressing anchors and the pipe wall. Expansion joints designed to handle thermal movement can mitigate this stress, protecting piping, pumps, and nozzle loads.
  • Isolating Pumps & Vibration
    Expansion joints can isolate equipment or structures from pipeline vibrations. During normal operations, equipment produces vibrations that can stress piping. Installing expansion joints can dampen these vibrations, preventing damage to critical equipment.
  • Settling in Old Plants
    In older facilities, alignment between equipment is often imperfect due to constant maintenance. Expansion joints can compensate for pipe movements and settling (compression, elongation, and lateral misalignment) without costly rework.

What Is Your Expansion Joint Capable Of?

End users should consider the capabilities of their expansion joints regarding safety, service life, and uptime. Performance ratings are assigned based on rigorous testing to meet Fluid Sealing Association standards. Validation testing of pressure/vacuum, movement, spring rates, and material compatibility ensures a long-lasting expansion joint that won’t fail at critical times, posing safety hazards.

Designing a best-in-class expansion joint requires a robust test and validation methodology. Theoretical designs and calculations establish expansion joint ratings, but destructive and nondestructive tests validate these ratings. Fluid Sealing Association standard tests include hydrostatic and vacuum testing, cycle life testing, and ASTM testing.

Durability Testing

Testing expansion joints under extreme conditions provides insights into their service life. This includes subjecting the joint to maximum pressure and temperature ratings and cycling between maximum compression and elongation. This simulates wear and tear over the joint’s cycle life.

Destructive Blow Out Testing

Pressurizing the expansion joint until failure or blowout establishes a safety factor and simulates a pressure surge, testing the joint’s limits.

Why Is This Important?

Safety is the top priority for manufacturers and end users. Engineers, procurement specialists, pipeline designers, and facility maintenance teams rely on accurate performance ratings. Many expansion joints handle caustic chemicals at high temperatures, posing immediate threats if they fail. Validation testing ensures the joint will operate safely within its ratings, providing excellent service life and keeping employees safe while avoiding costly downtime.

Doing More With Fewer Employees

Expansion joints are often overlooked in piping systems until a failure occurs. With maintenance and engineering teams stretched thin, end users need reliable parts. Proven validation testing reduces the burden on operations teams by ensuring the parts will perform as specified.

The End Goal

To make informed purchasing decisions, buyers, engineers, and maintenance teams need a comprehensive understanding of their expansion joints. Knowing the testing and ratings allows users to ask the right questions and trust the data sheet matches the product’s performance. The goal is to provide a best-in-class expansion joint backed by real-world validation testing, ensuring it is one of the safest and most reliable options on the market.

Ask yourself: What is your expansion joint capable of?

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