Milling method for liners extending into deviated wellbores
US5649595A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 1995 |
| Grant date | Jul 22, 1997 |
| Priority date | — |
| Expiry date | Jul 11, 2015 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B41/0042
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An apparatus and method of milling a liner extending from a deviated wellbore into a main wellbore is disclosed. The liner is inserted through a window and cemented in place with the cement extending back into the main wellbore. Mechanisms are provided on the liner to keep it away from the main wellbore casing wall to facilitate the proper operation of the washover tool. A top end taper is provided to help the washover tool reorient over the tubular liner if milling requires more than one trip into the well. A diverter is insertable prior to installation of the liner to assist in getting the liner to extend through a window. Upon milling through the liner, the washover tool straddles the diverter and latches into it to facilitate not only the removal of the diverter but also the entrapment of any debris created by the milling operation. Suitable sealing is provided with the diverter to keep the cement away from the latching mechanism during the cementing operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.