From casing window to new hole — the tools, the sequence, and why a matched system makes the difference between a routine operation and a gamble.
A poorly made window means stuck mills and junk left in hole, wrong window geometry, poor re-entry, and days of extra rig time. A reliable whipstock system converts a planned sidetrack into a routine operation: one clean window, correct geometry, and a casing exit the mill string finds on the first pass.
Correct geometry for re-entry, cut to the designed length and profile.
The mill string stays on the whipstock face — no walking, no extra trips.
Less rig time and fewer round trips on the most expensive asset on the pad.
Every Heverda whipstock system is supplied and quality-controlled as a complete package — not a random assortment of parts.
| Component | Function |
|---|---|
| Whipstock Body | Precision-machined deflection ramp that guides the mill string out of the casing wall. Face profile engineered for a clean, stable window over the full exit interval. |
| Anchor / Connector | Locates and locks the whipstock at the planned depth and transmits deflection loads to the casing. |
| Flex Mill | First-stage window opener — the flexible body follows the whipstock face to begin the exit through casing and cement. |
| Mechanical Lead Mill | Follows the flex mill to cut the full window length to designed geometry; available with lead-mill inserts for cutting performance and gauge maintenance. |
| Die Collar | Sets and verifies the anchor at depth, confirming tool position before milling begins. |
| Accessories | Hinge pins, lead-mill inserts and installation hardware — supplied with each system for a complete, ready-to-run package. |
The whipstock and anchor are run to the planned depth on the setting tool.
The die collar confirms the anchor is set and the tool is positioned correctly.
The flex mill follows the whipstock face and opens the initial exit through casing and cement.
The mechanical lead mill cuts the full window to the designed length and geometry.
The die collar confirms the anchor is set and the tool is positioned correctly.The window is dressed and debris circulated out for a clean re-entry profile.
| The drilling BHA passes through the window to drill the new hole. |
Every step is defined before the job: whipstock face angle, window length, and mill selection are engineered per well — not copied from a catalog.
| Parameter | Specification |
|---|---|
| Applicable casing sizes | 4-1/2" to 13-3/8" (custom sizes on request) |
| Connection threads | Per API Spec 7-2 / ISO 10424-2 (e.g. 2-7/8 PAC); other connections on request |
| Body material | 42CrMo (GB/T 3077) or AISI 4140, per agreed BOM |
| Tensile strength (heat treated) | ≥ 110 ksi (≥ 758 MPa), verified by mechanical testing report |
| Design basis | API 7-2 / ISO 10424-2; API 7-1 / API 7G workover practices where applicable |
Standard range is 4-1/2″ to 13-3/8″ casing; other sizes are engineered on request. Every system is configured to the customer’s casing program and planned trajectory.
Yes. Whipstock face angle, window length, and mill selection are defined per well, then dimensionally verified against the approved drawing before shipment.
A complete English technical file — mill test certificate, heat treatment and mechanical properties reports, chemical composition, dimensional inspection, NDT, and FAT report.
Wondering what a sidetrack could save on your next candidate well? Run our Sidetrack ROI Calculator.
Send us your casing size, planned window depth, and trajectory — we’ll respond with a recommended system configuration and quotation.
