Ziebel, a leader in composite rod well intervention, recently completed its 100th Z-Rod® distributed fiber optic sensing job. The Z-Rod system consists of a 6500 m carbon fiber composite rod with embedded fiber optic lines that make it possible to deploy both distributed temperature and distributed acoustic sensing along the complete wellbore. With a diameter of only 15 mm, the rod is injected into the well from coil tubing-like surface equipment and can travel up to 1,800 m along the horizontal section of a well. Unlike traditional logging tools that can only survey a few inches of the well at a time, sensing provides a complete wellbore profile that is captured several times per second.
The Z-Rod’s small diameter results in significantly reduced choking effects versus traditional coil tubing, enabling the Z-Rod to determine which perforated zones along the length of the wellbore are actually contributing to production. This information allows unconventional field operators to optimize their completion strategies.
The 100th job was performed for ConocoPhillips in the United States to determine the flow profile of zones within a fracked unconventional well. The 100 jobs were carried out using both land and offshore units in Norway, Denmark, Oman, Abu Dhabi, and the United States. Applications ranged from the evaluation of flow in unconventional wells to well integrity diagnosis, monitoring water injection schemes, gas lift optimization, and understanding inter-well communication and interference.