Available footprint on offshore platforms can be a significant challenge for Coiled Tubing (CT) operations. Many times a smaller CT unit is deployed for work that would be faster and operationally easier with CT of larger diameter. Often the platform’s crane capacity dictates the size of CT to be used, which in turn reduces the working envelope of the CT.
Some wells offshore India are completed horizontally and require intervention utilizing larger sizes of CT in order to gain horizontal reach and manipulate sliding sleeves. When CT is used for these operations, the weight of the CT reel itself is critical to the effectiveness of the overall operation and requires proper management. Traditional methods of managing / reducing CT reel weight involve spooling the CT string from a boat to the platform or joining CT sections by butt welding them together on the platform. Bringing the required length of CT onboard in two or more sections and joining them together utilizing the spoolable connector provides significant benefits over the traditional methods. The use of just one spoolable connector can reduce the maximum CT reel lifting weight by typically 30-40%, while increasing the CT size easily by one or two gauge sizes.
This paper describes the results of a feasibility study performed to address typical challenges and presents actual case histories in which a spoolable connector was used to connect two CT strings. Required equipment was built and mobilized so that two separate strings could be joined on the platform with the aid of a connecting jig. Several trips were safely performed without the need to change the spoolable connector. Specific benefits of the spoolable connector over the traditional methods are explained. Methods to monitor the usable life of the spoolable connector while tripping in and out of the well will also be discussed, as well as new developments currently underway.