Proper installation and maintenance of metal expansion joints is critical to ensuring long-term performance and avoiding premature failure. At US Bellows, we follow EJMA standards across every stage, from pre-installation inspection and correct lifting procedures to post-installation checks and periodic in-service monitoring. Every metal bellows expansion joint must be installed with the piping system fitted to the joint, never forced into position, as overstressing during installation directly reduces service life. Shipping devices must be removed after installation, and chloride-based cleaning agents must be avoided to protect bellows integrity. This guide covers everything engineers and maintenance teams need to correctly install and maintain pipe expansion bellows and expansion joint metal assemblies.
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Pipe Expansion Joints: Do’s and Don’ts: From the “Standards of the Expansion Joint Manufacturers Association, Inc”
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Do’s
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Don’ts
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Inspect for damage during shipment, i.e., dents, broken hardware, watermarks on the carton, etc.
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Store in a clean dry area where it will not be exposed to heavy traffic or damaging environment.
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Use only designated lifting lugs.
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Make the piping systems fit the expansion joint. By stretching, compressing, or offsetting the joint to fit the piping, the joint may be overstressed when the system is in service.
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It is good practice to leave one flange loose until the expansion joint has been fitted into position. Make necessary adjustment of loose flange before welding.
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Install joint with an arrow pointing in the direction of flow.
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Install single Van stone liners, pointing in the direction of flow. Be sure to install a gasket between the mating flange and liner.
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With telescoping Van stone liners, install the smallest I.D. liner pointing in the direction of flow.
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Remove all shipping devices after the installation is complete and before any pressure test of the fully installed system.
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Remove any foreign material that may have become lodged between the convolutions.
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Refer to EJMA Standards for proper guide spacing and anchor recommendations.
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Do not drop or strike carton.
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Do not remove shipping bars until installation is complete.
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Do not remove any moisture-absorbing desiccant bags or protective coatings until ready for installation.
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Do not use hanger lugs as lifting lugs without the approval of the manufacturer.
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Do not use chains or any lifting device directly on the bellows or bellows cover.
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Do not allow weld splatter to hit unprotected bellows. Protect with wet chloride-free insulation.
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Do not use cleaning agents that contain chlorides.
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Do not use steel wool or wire brushes on bellows.
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Do not force-rotate one end of an expansion joint for alignment of bolt holes. Ordinary bellows are not capable of absorbing torque.
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Do not hydrostatic pressure test or evacuate the system before installation of all guides and anchors. Pipe hangers are not adequate guides.
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Do not exceed a pressure test 1-½ times the rated working pressure of the expansion joint.
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Do not use shipping bars to retain thrust if tested prior to installation.
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Pipe hangers are not adequate guides.
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Refer to EJMA Standard for proper guide spacing and anchor recommendations.
NOTE: The manufacturer’s warranty may be void if improper installation procedures have been used.
