Type MPB-I

A pressure-relieved expansion joint is capable of absorbing axial and lateral motion, at the same time neutralizing the forces due to pressure. This is done by incorporating an additional bellows into the unit. This works in the opposite direction to the primary bellows and provides a force that ensures that no compressive forces arise at the ends.  

The Type MPB-I (in-line pressure balanced) is installed in a straight pipe system where there is no change in direction.

Pressure-relieved expansion joints are placed in similar piping systems as lateral and axial expansion joints with the great advantage that they do not transmit forces due to pressure on turbines or other sensitive equipment. The only force to be taken into account is the adjustment force to move the bellows.  

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