UNITED KINGDOM:

Coiled-tubing drilling tower improves safety, flexibility

A new, skiddable, coiled-tubing drilling (CTD) tower may set operational standards when it enters service for Phillips Petroleum Company Norway (PPCoN). Most CT towers are designed for specific platforms but, according to Alasdair Buchanan, region manager, Europe and Africa, of BJ Services, "The new CTD tower is so flexible it will operate on virtually any platform, handle extraordinarily large equipment, perform limited pipe handling of jointed tubulars, and can be used in standard well servicing work."

Skiddable coiled- tubing drilling tower offers flexibility and versatility.

This CTD tower allows fully free-standing, self-supporting operation in a safe working environment while using the injector at a considerable height. Even when drilling while fully overbalanced, having a lubricator long enough to accommodate the drilling tools offers greater operational maneuverability and improved well control. The CTD tower design incorporates two separate skidding systems: one for the main structure and one for the injector. The injector can also be turned on a swivel plate up to 60° in either direction. Incorporating multiple skidding functions permits the CTD tower to be rigged up wherever convenient.

When used with the new swivel system for the reel, it is possible to set equipment down once and perform service work on multiple wells, eliminating costly rig-up/down procedures, the risk of injury associated with these procedures, and freeing up cranes for other jobs on the platform. Incorporating a winch and traveling tong system further reduces pipe handling of jointed tubulars. The systems can also be used for stack, riser rig-up and tool deployment, further reducing need for cranes following initial set-up.

The dedicated CTD spread, which uses state-of-the-art remotely operated NORSOK V16 pump units, features a pressurized A60-rated control cabin, complete solids control unit, free-standing tower system, two HR 5100 injectors, sound-proofed 5,000-psi operating pressure power pack, and 75-metric ton capacity swivel base for the reel.

BJ Services built the CTD tower for PPCoN in Stavanger, Norway, and tested it on an Ekofisk platform. PPCoN plans to drill two wells in the Ekofisk field to further evaluate CTD technology, with the possibility of using it in the Eldfisk and Tor fields also.