How to Select the Right Expansion Joint for Your System

Expansion joints are vital to the integrity and efficiency of industrial piping systems.

Expansion joints are important parts of piping systems. They help protect critical infrastructure. They do this by allowing movement and reducing vibration in the pipes.

However, their effectiveness hinges on proper selection and installation. A failure in an expansion joint can lead to operational downtime, environmental hazards, and significant repair costs.

Expansion joints are flexible connectors in piping systems. They allow movement from thermal expansion, pressure changes, and mechanical forces. By allowing this movement, they prevent structural damage and can mitigate vibration.

This article shares important tips to help you choose the right expansion joint. This will ensure it works well and lasts a long time. We will focus on the most common types of joints: metal, rubber, and fabric. Each type has its own advantages and disadvantages.

Four Steps to Select the Right Expansion Joint

Step One: Gather the Right Information About Your Application

The most important step is to gather as much information about your application as you can.

This will be key to understanding what kind of expansion joint will work best.

Just remember the acronym STAMP:

• S: Size (Pipe Size)
• T: Temperature
• A: Application (Type of plant, media, corrosiveness, velocity, vibration)
• M: Movement & Overall Length of expansion joint
• P: Pressure

Step Two: Match Your Application Specs to the Right Type of Expansion Joint

Using the STAMP information you gathered from step one, you can match your application’s needs to the expansion joint best equipped to support it. Learning the advantages and disadvantages of each type of expansion joint will help you understand the limitations of each.

STAMP Category	Expansion Joint Material
	Metal	Rubber	Fabric
Size
Temperature	Cryogenic – High (1200+ F)	Low (up to 300 F)	High (1200+ F)
Application Type
Movement / Flexibility	Good	Better	Best
Pressure	FV up to 1000+ psi	Low to medium (Vacuum up to 300 psi)	Low (+/- 5 psi)
Other Expansion Joint Characteristics to Consider
Leak Tight?	✅	✅
Cost	$$-$$$$	$-$$	$-$$
Life of Expansion Joint	Best Some metal expansion joints can last 20+ yrs	Good Generally Rubber expansion joints have a shorter life than metal and may need replaced every couple of years	Good Fabric expansion joints will need replaced every couple of years but the metal frame can last a long time.
Maintenance	Minimal	Frequent (wear & tear)	Frequent (wear & tear)
Engineering Design & Standards	EJMA, ASME Codes (B31.3, B31.1, Section 8), EN	FSA	FSA

Step Three: Selecting the Bellows Configuration

The main job of an expansion joint is to absorb movement and vibration. Different types of expansion joints can also hold back the pressure thrust of the pipeline.

The movement, function of the expansion joint, and pipe layout will help narrow down the choices of the right expansion joint for your application.

At this stage you can also specify Dimensions and End Fittings (i.e, Flanges, weld-ends, threaded ends.)

Step Four: Engage the Experts

After reading this guide you may find that you are in a “gray area” where one or more types of expansion joints can be used. That’s where our expansion joint engineers can help.

Our skilled engineers can check your application’s details. They will conduct a pipe stress analysis, meet with you virtually, and make sure that the right expansion joint solution is selected to fit your piping system.

We have been designing and manufacturing engineered pipe expansion joints since the 1960s. We have been a proud member of the Expansion Joint Manufacturers’ Association (EJMA) since 2002, serving on both technical and management committees.

Conclusion

Choosing the right metal expansion joint is not just a technical need, it’s also a smart investment in the system’s safety and lifespan.

By following best practices, adhering to industry standards, and engaging with our engineers at US Bellows, we can work together to select the best expansion joint for your system’s needs. 

Doing this can prevent costly downtime, protect personnel, and extend the life of your infrastructure. Expansion joints may seem like small components, but their role in maintaining operational continuity is crucial and cannot be overstated.