Floating roof tank is not a new technology or equipments and it had been widely used over the
world in many industries. Storage tanks are designed, fabricated and tested to code and standard.
There are a variety of codes and standards stating the similar common minimum requirements
and some additional requirements from company standards orspecifications.
Engineer or tank designer who do the preliminary and detail design are normally not familiar or
not exposed to the actual site condition. Their designs are basically based on the code and
standard requirements and basic theory from reference book. Some would only rely on the
commercial software for the basic design, they have limited knowledge on the actual tank
operation which limit themon cost effectiveness and even safety detail design, particularly on
the floating roof tank.
There is limited procedure and rules in design the floating roof. These had resulted lots of
floating roof failure in the industry. Hence industry, tank owner and also the tank designer or
engineer need to have a simple rules and formula to ensure the floating roof is adequately
designed and strongenough for the various loading during operation.
Beside of the procedures and rules, understanding of how the stresses behave in the tank material
is essential for a complete safe design.
Floating roof tanks are usually built in a gigantic size and this would involve various disciplines
such as civil, chemical, mechanical, fire safety, construction, inspection, commissioning and
2The work scope of each disciplines would have a direct effect on the tank design, one example is
the tank foundation which is designed by the civil staff. The foundations are to be designed to
withstand the load of the tank with its content. Improper design would result in foundation
sagging or excessive soil settlement which in turn induces extra stresses to bottom of tank and
tank shell.Hence it is essential for the engineers or tank designer to know how and what effects each interdiscipline’s
design would have on one’s tank that affected the tank integrity, and taking all these
consideration into his design.
1.2 Research Goal
1.2.1 Project Aims
The aim of this project is to develop basic rules and procedures, highlighting the concerns in
designing, construction and operationof a floating roof.
1.2.2 Project Objective
The main objective of this project is “HOW TO DESIGN A NEW FLOATING ROOF TANK”.
Taking an existing Oil Development Project with it’s readily available information as a base, to
design the tank, and identify the problematic and lesson learnt throughout the project.
1.3 Research Methodology
1.3.1 Literature Review
Literature review is conductedto study the basic design and requirement of the floating
roof storage tank in the storage tank design code (API 650 – Welded Steel Tanks for Oil
Further studies on the tank design were made from other reference book, company
standard specification and information from different disciplines.
1.3.2 Case Study
Case studies on the previous project for the lesson learnt will be carriedout.
1.3.3 Product Enquiries
Research and study the role and application of the tank fittings and accessories by
searching information and sending technical enquiries to the product supplier, attending
the technical presentation conducted by the product supplier will be carried out.
1.3.4 Design Approach
Upon completion of the literature review, design approach is then developed. The storagetank design consists of two major designs, that is (1) the shell design analysis and (2) the
floating roof design.
In the shell design analysis, shell stress design will be performed taking into
consideration of all the considerably loading including hydrostatic pressure, wind loading
and seismic loading.
In the roof design, it consists of two sections, that is (1) roof stress design...