Why Use Expansion Joints? Axial Travel - “Maximum Travel” (±) may be called longitudinal movement or axial compression and extension. It is based on installation with no misalignment or angular deflection. How many Convolutions do I Need? 2 Convolutions - for minor movement between components Available 1" - 12" Least movement 1/4"- 1/2" Least Misalignment 1/8" - 1/4" Highest Pressure Ratings Full Vacuum Rated Misalignment - “Maximum Misalignment” may also be referred to as lateral offset or deflection. It is based on installation with no axial travel or angular deflection. 3 Convolutions- for moderate movement or misalignment Available 1" - 8" Moderate Movement 1/2"- 1-1/8" Moderate Misalignment 1/4" - 9/16" Moderate Pressure Ratings Full Vacuum Rated Angular Deflection - “Maximum Angular Deflection” may be called angular rotation. It is based on installation with no axial travel or lateral offset. 5 Convolutions - compensates for the most deflection, misalignment and axial travel Available 1" - 6" Highest Movement 1/2"- 1-1/4" Highest Misalignment 1/2" - 5/8" Lowest Pressure Ratings Not Vacuum Rated Vibration - In addition to noise, vibration transmitted through piping can cause leaks, premature equipment wear, and cracked welds. Expansion joints drastically reduce vibration transmission, thereby solving many of these issues.