As the number of deepwater installations increase, so will thenumber of coiled-tubing (CT) operations that are needed tosupport these deepwater fields. This need will growsignificantly as rigs on spar platforms and tension legplatforms (TLP) are eventually demobilized for work on newinstallations, leaving CT as the most economical option forperforming future well maintenance on these platforms.The need to operate without a rig is a critical factor in thesuccess of future coiled-tubing work in the deepwaterenvironment. Rigless operation is complicated by the fact thateach platform type has its own unique heave-compensationissues that must be addressed for an effective CT operation totake place.An additional challenge to deepwater CT operations hasbeen the assembly and installation of tension lift frames orheave-compensated jacking frames. This equipment istypically cumbersome and time-consuming to install and hasmany safety-related risks associated with the installation ofcoiled-tubing components.A new coiled-tubing heave-compensation system has beencreated to address issues associated with rigging up andoperating coiled tubing on deepwater installations. Thissystem was designed with particular focus on operationalsafety and efficiency to meet the complete range of floatingplatform coiled-tubing deployment scenarios. There are threeprimary modes of operation. As a stand-alone system, it canoperate as a heave-compensated jacking frame; with a rig, itcan operate as a standard tension lift frame or as a selfcompensatingtension lift frame. The adaptive heavecompensationsystem uses automated process control tomaintain wellhead loads within the American PetroleumInstitute-specified allowable stress limits. A specially designedproprietary titanium flex joint incorporated in the system reduces the effect of lateral loads and bending momentstransmitted to the wellhead.The total heave-compensation package is composed ofthree skids (injector tension frame, blowout preventer (BOP)tension frame, and hydraulic power unit). The injector,gooseneck, and all well control equipment come preassembledwithin the injector and BOP tension frames. This improves theoverall efficiency of the rig-up and eliminates most safetyissues associated with the rig-up/rig-down process. The heavecompensationsystem not only improves the efficiency of therig-up process but also makes tool changeouts more efficient.The initial field test data and the associated job casehistory establish the benefit that this new heave-compensationsystem has brought to the deepwater market.
展开▼
