Floating Roof Double Deck

Floating roof atmospheric storage tanks.

Floating roof double deck.

Over the years jm dixon associates has undertaken the design of many floating roofs both double and single deck for world renowned clients such as philips 66 exxon mobil and ineos. Different roof configurations were shown in figure 100 1. A stiffer floating roof pontoon or double deck would suffer much less than a frying pan type. You can use 2x material laid flat or 4x material also as sleepers.

The outer ring of the compartments is the main liquid tight buoyancy for the roof. You can do a floating deck and is really your only option. The two preferred configurations for external floating roofs are the double deck and the low single deck with 30 minimum pontoon area. It consists of an open topped cylindrical steel shell equipped with a roof that floats on the surface of the stored liquid.

Sketches are provided in the article depicting the pan type pontoon and double deck arrangement for external floating roof tanks. The sketches shown illustrate the above single deck and double deck floating roof with the critical components for these structures. In my humble opinion the double deck arrangement would be a more robust design but may cost extra and a detailed techno economic evaluation would be needed to arrive at the optimum option. Double deck pontoon roofs which are designed with concentric annular pontoons with radial bulkheads in each pontoon section.

In the same sealing condition compared with external floating roof tank internal floating roof tank can further reduce the volatilization loss as a result of that compared with double deck floating roof on external floating roof tank shaded by fixed roof and the gas phase layer between fixed roof and internal floating plate have a more significant effect on heat insulation. Double deck roof is much heavier than single deck one hence it is more rigid. Double deck roof figure 1 7 consists of upper and lower steel membranes separated by a series of circumferential bulkhead which is subdivided by radial bulkhead. External floating roof tank double deck type an external floating roof tank is a storage tank commonly used to store large quantities of petroleum products such as crude oil or condensate.

The low single deck is the more efficient of the two for 30 to 170 foot diameter tanks.