For offshore operations, the 'footprint' for a coiled tubing operation is generally larger than a wire line spread, which can limit the number of installations where coiled tubing can be performed and make the operation more costly. A coiled tubing operation is normally performed through the drilling derrick on the oil platform, which is used to support the surface equipment, although on platforms with no drilling facilities a self-supporting tower can be used instead. For coiled tubing operations on sub-sea wells a Mobile Offshore Drilling Unit (MODU) e.g. semi-submersible, Drillship etc. has to be utilized to support all the surface equipment and personnel, whereas wire line can be carried out from a smaller and cheaper intervention vessel. Onshore, they can be run using smaller service rigs, and for light operations a mobile self-contained coiled tubing rig can be used.
The tool string at the bottom of the coil is often called the bottom hole assembly (BHA). It can range from something as simple as a jetting nozzle, for jobs involving pumping chemicals or cement through the coil, to a larger string of logging tools, depending on the operations.
Coil tubing has also been used as a cheaper version of work-over operations. It is used to perform open hole drilling and milling operations. It can also be used to fracture the reservoir, a process where fluid is pressurized to thousands of psi on a specific point in a well to break the rock apart and allow the flow of product. Coil tubing can perform almost any operation for oil well operations if used correctly.
A Coil Tubing Unit (CTU) is a self-contained multi-use machine that can do almost anything that a conventional service rig does - with the exception of tripping jointed pipe. There are generally two types in shallow service - Arch and Picker. One uses a vertical elevator with a horse head on top, and an injector hanging by winch line off it. The Picker units have a picker, and a horse head bolted directly to the injector.
These type of coil tubing units have a semi-permanent drum mounted amidships (They are generally tandem drive Class 3 trucks, 40 feet (12 m) long or so)
The tool string at the bottom of the coil is often called the bottom hole assembly (BHA). It can range from something as simple as a jetting nozzle, for jobs involving pumping chemicals or cement through the coil, to a larger string of logging tools, depending on the operations.
Coil tubing has also been used as a cheaper version of work-over operations. It is used to perform open hole drilling and milling operations. It can also be used to fracture the reservoir, a process where fluid is pressurized to thousands of psi on a specific point in a well to break the rock apart and allow the flow of product. Coil tubing can perform almost any operation for oil well operations if used correctly.
A Coil Tubing Unit (CTU) is a self-contained multi-use machine that can do almost anything that a conventional service rig does - with the exception of tripping jointed pipe. There are generally two types in shallow service - Arch and Picker. One uses a vertical elevator with a horse head on top, and an injector hanging by winch line off it. The Picker units have a picker, and a horse head bolted directly to the injector.
These type of coil tubing units have a semi-permanent drum mounted amidships (They are generally tandem drive Class 3 trucks, 40 feet (12 m) long or so)
