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Tank piping

There are two types of foundation settlements, immediate or elastic settlement that will occur immediately after imposing loads and consolidation settlement that will occur over time. When you design your piping, immediate and consolidation settlement must be obtained from a structural engineer and taken into consideration. Last pipe spool will be installed after the tank hydro test when immediate settlement occur. Pipe support should be placed at maximum allowable distance to provide better pipe flexibility. In the case that pipe slippers are used, set the elevation of the pipe support at the maximum settlement point (or slightly more) bellow the initial elevation of the tank nozzle and use the shims. If you use steel pipe support, ship loose top plate and adjust support height in the field. Consolidation settlements that will occur over time will impose stress on the piping system and must be taken into consideration in the stress analysis. Please see the figure below.
1-tank-piping
In the mining industry, normally, we set a elevation of pump nozzle equal to elevation of a tank nozzle. If this is the case, make the pipe flexible by having at least one 90 degree elbow. Please see the figure below.
2-tank-pipe-flexibility
In the case of petrochemical piping, pipes are installed on slippers and typical tank piping arrangement is show on the figure below.
3-tank-farm-piping
Note that thank wall will be deformed under the hydrostatic pressure. When connecting piping is rigidly supported close to the tank nozzle, it will prevent the nozzle from rotating, causing a possible overstress at the nozzle-shell area. Please see the figure below.
4-tank-nozzle