An expansion Joint is used to absorb the expansion or contraction of piping due to temperature changes in the ambient air or fluid, movement of piping cause by uneven settlement of ground, earthquakes and wind pressure. To eliminate vibration and noise cause by the equipment such as pumps, turbines and blowers etc.
A bellows is a flexible seal, which is the coiled portion of an expansion joint. It is designed to flex when thermal movements occur in the piping system. The number of convolutions depends upon the amount of the force that must be used to accomplish this deflection. The convoluted element must be strong enough circumferentially to withstand the line pressure of the system, yet responsive enough longitudinally to flex. The longitudinal load must then absorb by some other type of devices, such as anchors, tie rods, hinges, or gimbal structures.
