Patent · US Expired

Wellhead retrieving tool

US6056049A · kind A · utility

11Cited by
13References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 1, 1998
Grant dateMay 2, 2000
Priority date
Expiry dateApr 1, 2018

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B33/035
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A wellhead retrieval tool is disclosed which is adaptable to a variety of configurations of wellheads. The tool comprises a spear through which a rotary cutter can operate. The tool can be adjustably supported off the top of the wellhead so that the grappling mechanism can be located at the proper distance for a grip on an inward upset or restriction within the wellhead. The clutching mechanism is located outside of the wellhead so as not to contaminate it with cuttings returned with the circulating fluid. The seal bore in the wellhead is protected by the tool to avoid damage. The dogs which engage the internal inward upset or restriction further have wickers or serrations on them to enhance the grip and to resist applied torque.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.