Casing Exit Interventions

Client demand for fast, less expensive, and safer methods to re-enter and work over wells has dictated significant growth in thru-tubing technology. Conventional drilling operations are expensive and time-consuming. The combination of technology advancements and experience has resulted in decreased costly downtime and improved drilling reach. Thru-tubing drilling technology, which includes coiled-tubing (CT) drilling and thru-tubing rotary drilling (TTRD), enables operators to access reserves that might otherwise be cost-prohibitive. These drilling solutions provide a total system for re-entering and sidetracking wells.

These systems fall into two categories: those for monobore casing exit operations and those for thru-tubing casing exit operations. Both provide optimal return for the challenge.

The monobore casing exit begins in a section of tubing and exits either a single string of tubing or multiple strings of tubing and casing. This type of operation requires the ability to orient and set a whipstock in a single-size ID casing. Thru-tubing exit operations are differentiated by the equipment requirements. The tools used must pass through large restrictions in a wellbore such as tubing strings, exit, and then set inside the larger casing string below.

Viewed for some time as a developmental technology, CT-deployed wellbore departure solutions have emerged as an innovative and reliable approach to address the first step in CT drilling and thru-tubing rotary drilling applications.

The following are common arguments for choosing casing exits over conventional workovers.

• Increased exposure to production zones
• Decreased expenditure for deep wells
• Adaptability and consistent operation in extreme environments and specifi c job requirements
• Rigless operation using e-line and CT workover units

Monobore and thru-tubing operations provide cost-effective and time-saving solutions to reach a lateral producing zone. Weatherford continues to meet these specialized thru-tubing operational challenges head on by providing a complete family of monobore and through-restriction casing exit systems.