Universal Expansion bellows

About Universal Expansion bellows

A Universal Tied Expansion Joint also called Universal Tied Bellows is designed to absorb large amounts of lateral transverse movement and some axial movement It consists of two bellows elements connected by a center spool with tie rods to restrain internal pressure thrust

What a Universal Tied Expansion Joint Contains

Component Description

Two Bellows Elements Corrugated metal eg stainless steel one on each side of the joint to allow flexibility in multiple directions

Center Spool PipeSpacer A straight pipe connecting the two bellows often customized in length based on lateral movement requirements

Tie Rods Tie Bars Usually 4 rods running parallel to the pipe axis fixed between the ends to restrain pressure thrust while allowing lateral deflection

End Connections Weld ends or flanges for installation into the piping system

Gusset Plates Lugs Welded plates on ends to mount the tie rods

Optional Internal Sleeves Protect bellows from media flow and reduce turbulence

Optional Flow Liners Improve flow characteristics and reduce erosioncorrosion inside the joint

Key Functional Characteristics

Feature Description

Movement Types Primarily lateral limited axial depending on tie rod design and flexibility No angular unless specially designed

Pressure Thrust Restraint Fully restrained by tie rods minimizing the need for strong anchors

Flexibility Range Greater lateral movement capability compared to singlebellows designs

Durability Ideal for long pipe runs and thermal expansion in multiple directions

Applications

Long pipe runs eg pipelines utility tunnels

Steam gas or chemical lines with significant lateral deflection

Systems with thermal expansion across offsets or loops

Piping where space constraints make axial expansion joints impractical

Design Notes

Tie Rod Orientation Parallel to axis restrains pressure thrust but allows lateral movement

Anchor Requirements Less demanding than untied joints but guides and intermediate anchors are still needed

Bellows Material Often stainless steel 304316 Inconel or Hastelloy depending on temperature and media