BREAKING CERAMIC DISKS IN HORIZONTAL COMPLETIONS – A NEW SOLUTION

Background

A client in the Middle East needed to break dual ceramic disks in an extended reach well at 18,600 ft MD. This particular well contained H2S and was located near a population center, so ceramic disks were used to provide a mechanical barrier during completion. Ceramic disks are typically removed using one of several methods: ruptured with pressure cycling, impacted and broken with slick line in low angle wells or milled with coiled tubing (CT) in high angle wells. CT performance and efficiency can suffer when attempting to break ceramic disks within long and highly deviated sections, as in this case.

Welltec® is well regarded in the region for tractor solutions in extreme wells and light, fast interventions. The client approached Welltec® for a solution to break the ceramic disks under a tight schedule.

OPERATION

Welltec® communicated with the ceramic disk manufacturer regarding potential solutions. Rather than milling the disks, the manufacturer recommended a solution using the Well Stroker® in which it would push a chisel into the disk to break it. A hard-tip chisel was designed specifically for this operation and quickly manufactured locally to meet the project’s time constraints.

Welltec® mobilized to the well, rigged up, and ran in hole with the Well Tractor® 318 and Well Stroker® with the newly produced chisel. At 7,074 ft, the Well Tractor® was started and conveyed the tool string over 11,000 ft through the lateral to the ceramic disks at 80° deviation. Upon reaching 18,600 ft MD, pick-up weight and correlations were made, and the disks were tagged. The Well Stroker® was engaged and stroked down with the hard-tip chisel, pushing against each of the two ceramic disks. The wellhead pressure dropped and the disks were presumed broken. The Well Stroker® stroked down multiple times to ensure that both disks were broken. The current remained flat, confirming the broken disks.

ACHIEVEMENTS

When called upon to do so, Welltec® developed an innovative tool to fit the available technology and perform the required task in less time and for less cost than traditional methods.

Welltec® and the service company managed to rig up, run in hole, tractor to 18,600 ft, break the ceramic disks, pull out of hole, and rig down all within the expected rig-up timeframe for CT. The speed and efficiency of this operation took less than 20 hours, reducing the typical time needed for the job as well as reducing the associated costs.

With the use of ceramic disks common in the region, the success of this job shows operators that Welltec® now provides an alternative to heavier and costlier traditional methods to break these barriers after wells are completed.

WELL TYPE:  OIL PRODUCER
MAX. TEMPERATURE:  220°F
BOTTOM-HOLE PRESSURE: 3000 psi
MAXIMUM DEVIATION 88°
TOTAL DISTANCE TRACTORED: 11,822 ft

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