Well abandonment and slot recovery
US11840900B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 2020 |
| Grant date | Dec 12, 2023 |
| Priority date | — |
| Expiry date | Sep 19, 2040 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B31/20
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A vibratory casing recovery bottom hole assembly and a method of recovering casing in a wellbore. The vibratory casing recovery bottom hole assembly includes a casing spear, a flow modifier and a dynamic amplification tool. The flow modifier produces cyclic variations in fluid pressure through the assembly at a first frequency and the bottom hole assembly is configured to have a natural or resonant frequency when vibrated to be near or at the first frequency. The dynamic amplification tool induces vibration in the bottom hole assembly while ensuring the dynamic amplification factor of the system is greater than one so as to transmit maximum vibration to the casing at the casing spear. Embodiments of dynamic amplification tools are described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.