Tension Leg Platform (TLP) Technology
The main principal of the TLP is to assure that the vertical
forces acting on the platform are in balance, i.e. fixed
and variable platform loads plus tendon tension are equal
to its displacement. The VCG should be close to the platforms
geometrical center. Positive displacement is obtained by
locking the platforms draft below the fixed and variable
payload displacement draft. This will result in an upward
force applied to the tendons, thereby keeping them in constant
a consequence the vertical platform motions (heave) is almost
eliminated, except for motions resulting from tendon elasticity
and vertical motion as result of environmental introduced
lateral platform motions. The tendons do allow a lateral
motion of the platform as a result of wind, wave and current.
This motion is similar to an inverted pendulum except for
the fact that the displacement variation by pulling the hull
down is giving a restoring force to the lateral movement.
The tendon tension is set within predefined values, or window
of operation. If the variable load of the platform exceeds
these values by adding risers or drilling loads etc., the
tendon pretension is adjusted by re-ballasting of the platform. Consequently
the hull is compartmented into void, machinery and ballast
spaces. The TLP has a control system monitoring ballast and
VCG. Seawater is used for ballast adjustment.
As an evolution of the Classic TLP design, the ETLP® (Extended Tension Leg Platform) design
has been developed. FloaTEC, LLC now exclusively owns the rights
to the ETLP® technology. Some of the drivers behind this design
- Wider tendon base for greater pitch stiffness (stability)
- Smaller spacing of deck supports for more efficient structure
- Lower rotational inertia for hull and deck for lower
pitch natural period
- A large moonpool can accommodate conventional top tension
- De-coupling of tendon porch separation distance from
the topsides deck design produces maximum design flexibility.
The ETLP® technology
has been successfully designed, fabricated, and installed
at the Kizomba A, Kizomba B Located offshore Angola and Magnolia
locations in the Gulf of Mexico.
TLP Heave Motion RAO’s;
BLUE OCEAN™ Project
FloaTEC, LLC has completed a significant front end engineering design (FEED) effort for our full drilling/production ETLP® hull configuration, called BLUE OCEAN™ Project. This "Off the shelf" design offers many benefits for an Operator looking to accelerate time to first production.
Copyright © FloaTEC, LLC 2010