In certain onshore Pakistan wells, coiled tubing intervention has been used in plug-and-perf operations. Although the plug-and-perf technique is well described in the literature, the existing studies mainly cover fracturing and reservoir productivity aspects. This paper highlights coiled tubing operational techniques that are integral and vital to the success of coiled tubing plug-and-perf multistage fracturing.
The application of coiled tubing plug-and-perf techniques to horizontal, high-temperature wells onshore Pakistan involved specific designs and new processes for the preparation, execution, and evaluation of the coiled tubing interventions. Planning and design considerations included the selection of the bottomhole assembly (BHA) in general and, in particular, the choice of logging head and upgrading the logging head operating envelope. During execution, efficiency was improved by reducing the number of coiled tubing runs with the use of addressable switches.
The plug-and-perf sequence with coiled tubing was repeated successfully in multiple wells. The combination of the addressable switches used as part of the BHA to enable setting the bridge plug and perforating multiple sets of perforations separately in a single run was shown to be very successful. The use of the plug-and-perf with coiled tubing technique improved overall project economics by reducing operating time to half for each zone. These successes validate the advantage of deploying coiled tubing for multistage fracturing operations. Multiple operators have realized the value of this technique compared to other techniques commonly used in such operations.