Abu Dhabi National Oil Company (ADNOC) has steadily advanced toward the use of a casing running tool (CRT) vs. conventional casing running methods to improve efficiency and safety. This advancement focused mainly on 9 ⅝ in to 20 in diameter casing and utilized internal grip tools. Recently they have searched for an external-grip CRT system that would allow them to effectively run the smaller diameter liners of both ferrous and chrome (Cr) materials, especially in the extended reach drilling (ERD) wells with maximum reservoir contact (MRC).
For 20 years CRT companies manufactured tools with gripping dies that could efficiently run ferrous material liners. Development of gripping mechanisms which can effectively run corrosion resistant alloy (CRA) materials has been met with varying success. Some of the challenges are to manufacture gripping dies from non-ferrous materials that will not contaminate the CRA liner and develop a gripping pattern that does not mark the CRA liner more than is accepted by API 5CRA industry standards, but maintain effective gripping force. In addition to hoisting and making up the string with no slippage it needs to perform fluid circulation at 3,000 psi. Until recently the liners were typically run in a conventional method using power-tongs.
One of the tools chosen for the trial runs was a well-proven, external-grip mechanical CRT designed specifically for smaller diameter casing and liners. It has a 500-ton hoist capacity and a 5,000 psi circulation rating and was packaged with a combination float and cushion tool and a wireless torque turn sub. Dies had been designed to meet the non-contamination and acceptable marking criteria previously mentioned and would be compatible with liners possessing as much as 25% Cr. The dies had been extensively lab-tested, including heavy pull tests and torque application tests, but had not previously been used in field applications.
The ERD-MRC well chosen for this trial was planned to have a record length of 6 ⅝ in, 24 ppf, 13% Cr liner with a wedge thread premium connection. In addition to not contaminating the liner, ADNOC expected an average running speed in joints per hour equivalent to the conventional casing running methods and a reduction in time during circulations.
The result of the trial was 589 connections (25,035 ft liner length) successfully run with an average running speed matching their expectations. The liner displayed very minimal marks and there were no issues when hoisting or torqueing the connections. In addition, there were no rejected connections during the run.
This publication will review the preparation for the run, actual run details, photos of the die marks, torque graphs and conclusions expressed by the operator with recommendations for changes moving forward.