Metallic Expansion Joints

About Metallic Expansion Joints

Metallic Expansion Joints are flexible connectors designed to absorb thermal expansion contraction vibration and misalignment in piping systems or ductwork They use metal bellows as the primary flexible element and are widely used in highpressure and hightemperature applications like power plants refineries chemical plants and HVAC systems

What Are Metallic Expansion Joints Made Of

A typical metallic expansion joint contains

Metallic Bellows Element

Made of stainless steel or other alloys eg Inconel Monel Hastelloy for corrosion and temperature resistance

Corrugated design provides flexibility for axial lateral and angular movements

End Connections

Weld Ends or Flanges for integration into the pipeline or equipment

Optional Internal Components

Inner Sleeve Flow Liner Protects bellows from erosion turbulence and highvelocity media

Outer Cover Shroud Provides mechanical protection and shields against environmental damage

Optional Restraints Hardware

Tie Rods Control pressure thrust and limit movement

Hinges or Gimbals Enable angular movements while absorbing pressure thrust

Limit Rods Prevent overextension or compression

Functions of Metallic Expansion Joints

Absorb thermal expansion and contraction of piping

Isolate vibration and noise from rotating machinery

Compensate for minor misalignment

Reduce load on anchors and equipment

Types of Metallic Expansion Joints

Single Axial Expansion Joint Absorbs axial movement only

Universal Expansion Joint Two bellows connected by a spool for large lateral movement

Hinged Expansion Joint Absorbs angular rotation in a single plane

Gimbal Expansion Joint Handles angular rotation in multiple planes

Pressure Balanced Expansion Joint Compensates for axiallateral movement while neutralizing pressure thrust

Advantages

High strength and durability under pressure and temperature extremes

Suitable for steam gas oil and chemical pipelines

Longer service life compared to rubber or fabric joints