There is no unique way of classifying
tanks based upon a single criterion such as shape or roof type.
However, the nature of the pressure due to the substance stored in
the tank determines the shape of the tank to be used.
o Cone-roof tanks (usually supported by an
o Dome-roof tanks (usually self-supported
o Flat-roof tanks
o Spherical tanks
• Roof supports
o Rafters and girders
o External floating roof
o Internal floating roof
• Bottom plate
Spherical tank typically used to store gas. External
stairs are used to access the top of the tank.
tank with a dome roof (Bacardi, Cataņo, Puerto Rico).
dome roof in Stolhaven, Louisiana.
Tank with conical roof, Yabucoa, Puerto Rico. This
tank has a reinforcing ring stiffener.
This tank with a conical roof has rafters and girders
to support the roof. Further, there is a central column.
Aerial view of a tank with a floating roof,
Chalmette, Louisiana. The dike is full of liquid due to flooding
after Hurricane Katrina, 2005. The tank has a ring stiffener which
is also used for walking around the tank.
external floating roof in a large tank (CAPECO, Cataņo, Puerto
Rico). The stairs slide as the floating roof elevates due to
increasing fluid inside the tank.
roof may have a complex mechanism to avoid gases accumulating on top
of the fluid by means of a pontoon resting on the fluid. There are
various models of sealing rings to allow vertical displacements.