Ron Sanders briefly describes the definition of a liftboat and the evolution of the liftboat industry. February 3, 2012.
What is a Liftboat?
- Written by: Larilla Templeton and Elijah Echeveste
- Published: May 6, 2012 at 6PM
- Last updated: May 6, 2012 at 6PM
A liftboat, not to be confused with a conventional jack up drilling rig, is defined as a self-elevating, self-propelled vessel equipped with at least one crane and with open deck space that can be used for multiple purposes.
Liftboats are the trucks of the offshore fleet. They carry any kind of equipment necessary to do whatever the job requires.
Liftboat jobs include wireline, crane operations, pipe-laying, diver support platforms, work over and offshore coiled tubing operations, temporary housing for construction and service crews, wind turbine installation and servicing, and so on. The list of uses will be limited only by the vision of the operators and demands of the market. Worldwide, the fleet consists of some 175 vessels of various sizes and capabilities.
Liftboats are classed by leg length that, with allowances for penetration, air gap and leg reserve, translates as water-depth capability. Some of the smaller boats, dating back from the earliest days of the industry (1950s), were designed to operate in water depths of only 1½ feet. At the other extreme, Levingston’s liftboats can work as deep as 216 feet (66 meters).
Crane capacity and deck loads vary as much as water-depth ratings. For example, EBI’s Frank Sembra, a 62' class liftboat, has one eleven-ton crane and carries up to 30 tons on deck. Montco’s 335' class liftboat, the Robert, can accommodate one and one half million pounds of deck load capacity, with three offshore pedestal cranes with capacities of 27, 66, and 550 US tons.
For specifications on liftboats, check the database within this site. Most liftboats are built on barge hulls for maximum deck load. One or two directly coupled diesel engines provide propulsion. Legs are tubular and operated by a simple hydraulic system. But this is changing. Some of the newer vessels employ truss legs (lattice legs) and thrusters for enhanced maneuverability. New, high-speed jacking systems include instrumentation to monitor the loading on each pinion, jacking speed and overall system function.
The liftboat industry has seen a tremendous change from within the liftboat fleet themselves. They are now getting increasingly larger with more to offer. Liftboats are starting to surface around the world as the new, multipurpose, self-elevating, self-mobilizing, cost efficient workhorses of the sea.