Drydocks World and Maritime World, a leading provider of maritime and offshore services to the shipping, oil, gas and energy sectors, has won the ‘Innovative solution’ Award at the distribution of ‘International Business Excellence Awards’ ceremony,  for constructing subsea oil storage tank Solan.

The firm began working on the subsea oil storage tank in 2013 and delivered the project last year, said a statement.

Solan accommodates more than 400,000 barrels of oil under the sea. The idea behind the construction of this huge tank was to reduce the extended pipelines under the sea to transfer oil, and therefore reducing the negative impact on the environment to a large extent, with the oil transferred directly from the tank to the oil tanker.

In co-operation with the client Premier Oil, Drydocks World constructed the largest and deepest subsea oil storage tank comprised of a 45m x 45m x 25m structural tank weighing approximately 10,150 tonnes in eight mega blocks, connected with pile sleeves and mud mats.

The Solan tank was floated over onto a heavy lift transportation vessel and was successfully installed in a water depth of 130m.

The tank now resides under the sea in the Scottish Shetland Islands. The company’s achievements on this project included lifting a 7,170 tonne structure, skidding the facility from the General Assembly Area to the dry docking area for load out and installing a 895 tonne block on the tank using the shipyard’s floating crane.

The subsea oil storage facility was built to extremely exacting standards.  Each and every weld joint was recorded and documented with details of the welder, weld method and date.

Complete welding totalling 120,000 meters, NDT tested and recorded. Of this over 60,000 metres of joints were ultrasonically scanned, ensuring the highest possible quality standards in welding.

The facility has four quadrants with watertight bulk heads and eight pile sleeves with mud mats.

The weight of piping installed as part of the facility was 171 tonnes which comprised ballast, displacement, oil inlet and outlet piping systems. A number of piping materials were used including super duplex and carbon steel.  

Other systems installed as integral parts of the facility include the Temporary Level Monitoring (TLMS), Permanent Level Measurement (PMS) and Corrosion Protection  Monitoring (CPMS) systems.With the implementation of the ‘Zero Harm’ initiative and high standards in HSE, the project was successful in achieving 2.5 million LTI free man hours.  - TradeArabia News Service