floating roof structure

An internal floating roof is a floating cover that floats on the surface of an oil tank and moves up and down with the level of the oil. Using an internal floating roof to cover the liquid surface is the most economical and simple method for reducing evaporative losses of the product. Statistical evidence shows that tanks equipped with internal floating roofs can reduce oil and gas losses by over 95% compared to tanks with arch roofs. 1 Buoy-type floating pad: The buoy-type floating pad is mainly composed of a top plate, buoys, buoy supports, pillars, and peripheral seals ； In use, the floating disc floats on the liquid surface thanks to the buoyancy of the float; inevitably, the lower half of the float sinks below the liquid surface while the upper half remains above it, thereby creating a stable gas-liquid phase equilibrium space between the liquid surface and the deck plate. Float-type floating pads feature low weight, simple construction, easy installation, and convenient maintenance. However, due to the presence of a gas phase space, they are slightly inferior to box-type floating pads in terms of sealing performance, structural strength, and resistance to oil and gas impacts. 2 Fully submerged floating pad: The fully submerged floating pad is mainly composed of a main beam, floating boxes or honeycomb boxes, supports, and peripheral seals ； The floating platform is formed by assembling multiple floating boxes or honeycomb boxes to create a large, mesh-like, hollow floating box. In use, the lower part of this floating platform is submerged in the liquid surface, with the entire structure floating on the surface; this separates the gas phase above from the liquid phase below. A gas space may only exist in the gaps between the components, serving to cover and seal the liquid. The box-type internal floating disk features energy efficiency and environmental friendliness, simple construction, and good structural stability. It boasts high overall structural strength and a compact design, giving it excellent seismic resistance. Compared to other types of floating disks, it offers comprehensive technical improvements that minimize the presence of oil and gas pockets. However, considering its overall structure, it has certain limitations in terms of operational stability and ease of maintenance; moreover, it requires a large amount of consumables which increases costs, resulting in an overall cost that is 1.5 to 3 times higher under the same conditions. Box-type floating pads are considered only for special media (such as toxic ones).