The Effects of Fluid Hammer Tools and Lubricants on Plug Milling Efficiencies - A Comparative Study

Abstract

AbstractLong-reach horizontal wells with "Plug and Perf" completions are commonly used to achieve economic production in today’s unconventional reservoirs. After the multistage fracture stimulation operations are completed, coiled tubing (CT) is often used to remove the plugs. However as the lateral reach of wells increase, plug removal using CT becomes less efficient as weight on bit (WOB) decreases. Over the last few years, various fluid hammer tools have been introduced to the industry and have improved plug milling times significantly.This paper will review the results and operational improvements observed from milling operations using both fluid hammer tools and/or lubricants. Data from shale formations across the U.S. (Eagle Ford, Bakken, Haynesville, Barnett and the Marcellus) is included. Analysis from the use of three types of hammer tools and/or lubricants will compare results to those of base case operations completed without fluid hammer tools or lubricants.The paper will detail improvements in milling efficiencies, number of stalls, and stuck pipe incidents. Results will focus on when to run hammer tools and when to introduce pipe lubricant to achieve optimum efficiencies.Many operators rely on word of mouth to design and perform extended-reach CT milling jobs. This can result in poorly executed, ‘non-engineered’ plug milling operations. This paper will provide data to assist operators in improving their completion efficiencies