Patent · US Expired

Method and a drilling rig for drilling a bore well

US4850439A · kind A · utility

71Cited by
7References
26Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 7, 1987
Grant dateJul 25, 1989
Priority date
Expiry dateJul 7, 2007

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B19/20
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

Drilling equipment, especially for offshore use, comprises a drill floor or platform (11) with a derrick (10) extending upwards therefrom. A first hoist (12) connected to the upper part of the derrick is used for passing a length of a tubular body (19), such as a drill string or a well casing, through a drilling opening (18) defined in and extending through the drill floor. The tubular length is connected to or disconnected from the drill string or well casing during the drilling operation, and such tubular lengths are strored in a storage area (31, 32) of the drill floor. The tubular lengths may be transported from the storage area to the first hoist (12) and vice versa by means of first transporting means (22). The drill floor or platform (11) also defines a preparation opening (21) extending therethrough at a location spaced from the drilling opening and from the storage area, and a second hoist or a preparation hoist (20) is connected to the upper part of the derrick above the preparation opening. Two or more tubular sections may then be assembled to tubular lengths at the preparation opening by means of the preparation hoist while the drilling operation is going on at the dril…

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