How to Properly Install and Maintain Metal Expansion Joints?

This article is a brief installation and maintenance guide for metal expansion joints. To better install and maintain the pipe expansion joints, users must obey to certain rules. Please check following tips about something you should and shouldn’t do regarding to pipe expansion joints.

Something you are not supposed to do on pipe expansion joint:

Do not remove any moisture-absorbing desiccant bags or protective coatings until ready for installation.

Do not use hanger lugs as lifting lugs without approval of metal expansion joints manufacturer.

Do not allow weld splatter to hit unprotected metal expansion joints. Protect with wet chloride-free insulation.

Do not drop or strike carton.

Do not exceed a pressure test 1-½ times the rated working pressure of the metal expansion joint.

Do not remove shipping bars until finish installation.

Do not use cleaning agents that contain chlorides.

Do not force-rotate one end of an pipe expansion joint for alignment of boltholes. Ordinary bellows are not capable of absorbing torque.

Do not use chains or any lifting device directly on the bellows or bellows cover.

Do not use shipping bars to retain thrust if tested prior to installation.

Do not hydrostatic pressure test or evacuate the system before installation of all guides and anchors. Pipe hangers are not adequate guides.

Do not use steel wool or wire brushes on pipe expansion joints.

Bellows Pipe Expansion Joints

Something you are supposed to do on pipe expansion joint:

Install single Van stone liners, pointing in the direction of flow. Be sure to install a gasket between the mating flange and liner.

Store the metal expansion joints in a clean dry area where it will not be exposed to heavy traffic or damaging environment.

Use only designated lifting lugs.

It is good practice to leave one flange loose until the pipe expansion joint has been fitted into position. Make necessary adjustment of loose flange before welding.

Remove any foreign material that may have become lodged between the convolutions.

Install the metal expansion joint with arrow pointing in the direction of flow.

With telescoping Van stone liners, install the smallest I.D. liner pointing in the direction of flow.

Make the piping systems fit the pipe expansion joint. By stretching, compressing, or offsetting the metal expansion joint to fit the piping, the joint may be over stressed when the system is in service.

Remove all shipping devices after the installation is complete and before any pressure test of the fully installed system.

Inspect for damage during shipment, i.e., dents, broken hardware, water marks on carton, etc.