For exiting standard steel casing below the production tubing or other restrictions, and delivering a 3- to 15-ft rathole, the Trackmaster TT thru-tubing whipstock system offers a cost-effective alternative to pulling completion tubing from existing wells prior to sidetracking. The tool is designed to pass through the tubing ID; once below the tubing string, it can be hydraulically anchored inside the liner to enable window milling operations. Its unique geometry compensates for the relative size difference between the whipstock and casing diameters. This nonretrievable thru-tubing system includes a debris barrier and a multicycle bypass valve to facilitate fluid flow that is sufficient to operate MWD tools.
Running in with the whipstock, orienting and setting it, milling the window, and drilling the rathole can all be accomplished in a single trip. Alternatively, the milling assembly can be run in separately. Coiled tubing or jointed pipe can be used to deploy the whipstock.
The hydraulically actuated expandable anchor spans multiple casing sizes and weights. It uses an antirotational, high-axial-load slip design, which provides maximum centralization and stability.
A hydraulically actuated hinge section kicks the bottom of the whipstock ramp against the casing wall. This section spans the ID of the casing, locking the ramp in place and preventing movement during the milling operation. In addition, it helps to keep the mill on the ramp, forcing the mill to engage the casing.
The profile of the ramp section compensates for its tilted position across the casing. The EZ Glyde multiangle whipstock ramp ensures continuous mill contact with the casing wall during the milling operation.
Two different mills are available with the Trackmaster TT thru-tubing system for consistent, fast, and reliable performance: