A condenser shell may be fitted with an expansion joint if the:

Condenser tubes that are expanded into the tube sheets create a fixed connection between the tube and the sheet, which can introduce stress due to thermal expansion and contraction. When the condenser operates, temperature variations cause the tubes and the tube sheets to expand and contract at different rates. This misalignment can lead to mechanical strain and potential damage.

Fitting an expansion joint to the condenser shell allows for some flexibility in this system. An expansion joint accommodates the movement caused by thermal expansion, helping to prevent stress on the tubing and the tube sheets. This is particularly important when the tubes are rigidly fixed at the tube sheets, as they lack the flexibility needed to accommodate differences in thermal expansion.

While other factors such as the type of construction or the shape of the tubes might influence the design considerations of a condenser, the critical aspect in this context is the expansion of the tubes into the sheet. An expansion joint serves to mitigate the stresses resulting from this connection, ensuring greater integrity and longevity of the condenser.