Drill string suspension tower
US4341270A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 16, 1980 |
| Grant date | Jul 27, 1982 |
| Priority date | — |
| Expiry date | Jun 16, 2000 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B19/084
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Improved means for suspending a drill string using a pair of hydraulically actuated belts is disclosed. A derrick or tower is mounted to a base to overlie a standard rotary drill table. The drill string (comprising a number of drill pipes and a drill collar) and a drill bit are suspended within the hole being drilled by a hook. A hook support rides between a pair of vertical guide rails and supports the hook between the rails via a pair of belts which engage the hook support. The belts extend from the hook support, to the stationary pulleys at the top of the tower, and down to an alternating series of stationary and movable pulleys which define a variable length path along which the belts are guided. When it is desired to raise or lower the hook, and therefore the drill string therefrom, the hydraulically actuated, movable pulleys are either raised or lowered to change the length of the variable length path and consequently the length of belt along the path.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.