Untied Expansion Joint Designs
Untied Expansion Joints
Most Common Types:
Axial Expansion Joints
Double Expansion Joint
Internally Guided Expansion joint
Untied Universal Expansion Joints
Pressure Balanced Expansion Joint
Features :
Single or dual bellows with installation fittings only
Commonly used for low pressure service
Simple design= less expensive
All degrees of freedom(axial, lateral, angular)
Incur pressure thrust onto pipe
Anchors affected by bellows spring rate and pressure thrust=higher force
Basic Expansion Joint Designs
Untied=Pressure Thrust
Single (axial)
Expansion Joint
Axial ,lateral & angular movements
Universal(untied)
Expansion Joint
Large axial , lateral & (angular)movements
