Part II: Types of Offshore Platforms

Ladies, here we meet again for Part II. Ok last time I already explained about the introduction of the offshore structures and now we move to the main contents, types of offshore structures. Either fixed or float, as simple as that. Ah, layman terms. Fixed platforms is a platforms that its substructure attached / piled to the seabed while floats platforms does not. However, floating systems normally moored i.e chained or anchored.

Fixed Platforms

Steel Jacket Platform

Semangkok-A Platform

In Malaysia, especially in Peninsular Malaysia (PM) blocks, water depth is range to 50-70 metres (shallow waters). Hence, it is economically feasible to built a steel jacketed platforms. But the application of the jacket platform usually up to 300 metres. Topside of jacket platform are normally built either integrated (alltogether) or modular type (section per section e.g Living Quarters + Power Generation + Booster Compression + bla bla bla). For middle school level of understanding, JACKET PLATFORM = TOPSIDE + JACKET.

Compliant Tower

Compliant Tower Design

Petronius - Compliant Tower Platform

Obviously, the compliant tower platform are designed for water depth more than jacket platform which are normally up to 600 metres. The difference with jacket is that it has more narrowed frame support structure by a piled foundation. Compliant towers are designed to sustain significant lateral deflections and forces. Kids, read this out loud. COMPLIANT TOWER = TOPSIDE + FLEXIBLE TOWER.

Concrete Gravity Structure

Hibernia Platform

Practically, this type of structures are being used in the harsh environments such as North Sea and Scandinavian. Also known as Gravity Base Structure (GBS) platform, it is design to withstand the loads (environment + iceberg) and also for the storage of its base support. Normally GBS is applicable for water depths up to 300 metres. When completed, a GBS is towed to its intended location and sunk. Again kiddos, GBS = TOPSIDE + CONCRETE BASE.

Part I: Types of Offshore Platforms

Hola dudes, feelin' good? Yeah, buckle up ladies cause today I will babbling about types of offshore platforms available in the upstream sector. Ahh before that, should I become a lecturer? First of all, I would like to differentiate between oil rigs and platforms as this will help for a better understanding.

Oil rig is a mobile offshore unit that floats and may placed for temporary works or jobs. It can be categorised as MODU (Mobile Offshore Drilling Unit) or MOPU (Mobile Offshore Production Unit). MODU is basically used for drilling works before the production and processing parts comes in. It can be known as semisubmersible drilling rig, barge rig, drillship etc. For MOPU, it serves on the marginal field, which is not economically viable to put an offshore platforms. Hence, these rigs practically contracted on leasing basis.

MOPU - SBM

Semisubmersible Drilling Rig - Transocean's Nautilus