How are jack-up rigs transported?
How are jack-up rigs transported?
While some are capable of self-propulsion and do not need an outside source for movement, most jackups are transported via tug boats or submersible barges. While towing is easily performed, barges are the transportation of choice when the jackup needs to be moved quickly or over a longer distance.
Do jack-up rigs have anchors?
Jackup rigs are so named because they are self-elevating with three, four, six and even eight movable legs that can be extended (“jacked”) above or below the hull. This anchors the rig and holds the hull well above the waves.
What is a jackup drilling rig?
1. n. [Drilling] A self-contained combination drilling rig and floating barge, fitted with long support legs that can be raised or lowered independently of each other. The jackup, as it is known informally, is towed onto location with its legs up and the barge section floating on the water.
How do jack-up barges work?
HOW DOES A JACK-UP LIFT BARGE WORK? A jack-up lift barge, much like a traditional rig, has long support legs that can be raised or lowered. The barge self-propels with its legs up and its hull floating on the water, and once on location, the legs are jacked down onto the seafloor.
How are drilling rigs moved?
If it is a wet tow where the rig is moved by tugs, around 3-4 knots for a jack up and 5 knots for a floater. On a dry transportation when they are loaded onto a ship they can travel around 14 knots.
What is the purpose of a jack up boat?
Liftboats are commonly used to perform maintenance on oil and gas well platforms. The liftboat usually moves on location on a side of the platform where no obstructions or pipelines are observed, lowers its legs and jacks up out of the water.
How is an oil platform anchored?
They are generally anchored by combinations of chain, wire rope or polyester rope, or both, during drilling and/or production operations, though they can also be kept in place by the use of dynamic positioning. Semi-submersibles can be used in water depths from 60 to 6,000 metres (200 to 20,000 ft).
What is jack-up preloading?
Preloading operation is to apply loads on the legs of the jack-up to a pre-determined load level to ensure that the soil resistance is sufficient for the foundation to resist the maximum design loads (includes environmental loads) for operational in that location.
How much does it cost to move a drilling rig?
Moving a regular rig can take days and cost up to $1 million. The allure of such savings is hard for shale producers to pass up.
How to elevate a jack-up Hull?
However, one of the well-known methods of elevating the jack-up hull is Rack and Pinion. This system uses multiple Hydraulic or Electric Motors and gearboxes to distribute the torque between all legs to lift the whole platform smoothly and simultaneously.
What are JackJack-up barges?
Jack-up Barges, Self-elevating Platforms, Lift boats & Spud pontoons are a type of mobile unit that consists of a rectangular hull fitted with usually three to four, round or square legs, capable of raising its hull over the surface of the sea.
How many motors does it take to jack up a boat?
The jacking speed is not adjustable during the operation unless two-speed motors are chosen. A typical jacking system for a four-leg liftboat uses 72, 120, and even up to 144 motors working in combination to share the load to elevate or lower the hull against gravity.
What is a jack-up rig?
A jack-up rig is a type of offshore mobile platform that consists of a buoyant hull fitted with some movable legs, capable of raising its hull over the surface of the sea. The buoyant hull enables transportation of the unit and all attached machinery to the desired location.
