Hosemaster
Metal Expansion Joints

Application:

Because expansion joints are designed to accommodate pressure and movements without the need for braid, they are capable of handling all three planes of movement: lateral, angular, and axial. Expansion joint movement and pressure bearing capabilities are determined by the number of convolutions, as well as material thickness, number of plies, and wall height specified by the product’s individual design. Multi-ply expansion joints are ideally suited for applications where vibration may be present. Additionally, multi-ply designs feature lower spring rates which reduces stress on piping components, and increases cycle life for a given installation.

Expansion Joint Types

Internal Liners

Comparison of Ratings, Features, and Available Options

EJ Styles	Relative Movement Capability			Relative Spring Forces			Pressure Thrust on Piping System	Available Features
	Axial	Angular	Lateral	Axial	Angular	Lateral		Internal Flow Liner Types	External Cover	Redundant Ply Design	End Connection Types
US Unrestrained Single	↔	↔	↓	↔	↔	↑	YES	SWTWFWSDTD	YES	YES	BBWEFFVFLJ
LS Limit Single	↔	↔	↓	↔	↔	↑	YES	SWTWFWSDTD	YES	YES	BBWEFFVFLJ
TS Tied Single	—	—	↓	—	—	↑	NO	SWTWFWSDTD	YES	YES	BBWEFFVFLJ
HS Hinged Single	—	↔	—	—	↔	—	NO	SWTWFWSDTD	YES	YES	WEFFVFLJ
SHS Slotted Hinged Single	↔	↔	—	↔	↔	—	YES	SWTWFWSDTD	YES	YES	WEFFVFLJ
GS Gimbaled Single	—	↔	—	—	↔	—	NO	SWTWFWSDTD	YES	YES	WEFFVFLJ
UU Unrestrained Universal	↔	↔	↑	↔	↔	↓	YES	SWTWFWSDTD	YES	YES	BBWEFFVFLJ
TU Tied Universal	—	—	↑	—	—	↓	NO	SWTWFWSDTD	YES	YES	WEFFVFLJ
PBS Pressure-Balanced, Elbow, Single	↔	—	↔	↔	↔	↑	NO	SWTWFWSDTD	YES	YES	WEFFVFLJ
PBU Pressure-Balanced, Elbow, Universal	↔	—	↑	↔	↔	↓	NO	SWTWFWSDTD	YES	YES	WEFFVFLJ
PBI Pressure-Balanced, In-Line	↔	—	—	↔	—	—	NO	SWTWFWSDTD	YES	YES	WEFFVFLJ
EPS Externally-Pressurized Single	↑	—	—	↔	—	—	YES	FW	INCL	YES	WEFFLJ
EPD Externally-Pressurized Dual	↑	—	—	↔	—	—	YES	FW	INCL	YES	WEFFLJ

Pre-Engineered Expansion Joint Types

Basic Bellows

A bellows can be supplied without end fittings for field installation. The skirt (straight portion at each end of the bellows) can be sized to fit a flange or pipe. Please specify skirt length and attachment type when ordering.

Unrestrained Single

Example of an unrestrained single expansion joint used in a proper piping system to absorb axial pipeline expansion.		Example of an unrestrained single expansion joint used in a proper piping system to absorb lateral deflection, as well as axial compression.

An unrestrained single expansion joint is best used when piping systems are equipped with proper guides and anchors to absorb axial, angular, and a small amount of lateral movement.

Limit Single

A limit single expansion joint is best used when main anchors and guides are in the pipeline. It allows for some axial movement as well as lateral movement; however, the hardware protects the expansion joint from exceeding its design movements.

Tied Single