EXPANTION JOINTS

We can produce expansion joints complete of flanges and to be pipe ends. The different terminal are generally produced in carbon steel. On request, it is possible to use stainless steel. Standard flanges are bored according to UNI - ANSI rules, or special and in above mentioned materials.

To avoid direct contact between bellow and fluid a sleeve is welded on the internal side of the expansion joint. It allows to reduce thermal strains, to reduce loss of head, turbulences and erosion.  

To protect waves from foreign bodies or to facilitate the application of the insulation, bellow, can externally be wound by a plate, generally in carbon steel.

According to the use we can distinguish:

• tie rods as run limiting device

• tie rods for pre-setting to the mounting

• tie rods to support the thrust due to internal pressure.

When we have to plan a bellow subjected to high pressure it is necessary to use reinforcing rings made of carbon steel sheet. Besides uniformly distributing the compensator, they also act like run limiting devices.

To allow to the axial expansion joint to perfectly carry out its function, it is necessary to limit strengths (displacements and rotations) generated on pipeline, using fixed points. 
Usually fixed points are distinguished in:

• main fixed point PF

• intermediate fixed point PI

An appropriate positioning of fixed points and guides in a pipeline, can check the movement of the expansion joint.