Pressure pulse generator for measurement-while-drilling systems which produces high signal strength and exhibits high resistance to jamming
US6219301A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 20, 1998 |
| Grant date | Apr 17, 2001 |
| Priority date | — |
| Expiry date | Oct 20, 2018 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/18
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A system is disclosed for generating and transmitting data signals to the surface of the earth while drilling a borehole, the system operating by generating pressure pulses in the drilling fluid filling the drill string. The system is designed to maximize signal strength while minimizing the probability of jamming by drilling fluid particulates. The system uses a rotary valve modulator consisting of a stator with flow orifices through which drilling fluid flows, and a rotor which rotates with respect to the stator thereby opening and restricting flow through the orifices and thereby generating pressure pulses. The flow orifices with the stator in a "closed" position are configured to reduce jamming, and to simultaneously minimize flow area in order to maximize signal strength. This is accomplished by imparting a shear to the fluid flow through the modulator, and minimizing the aspect ratio and maximizing the minimum principal dimension of the closed flow area. A preferred embodiment and three alternate embodiments of the modulator are disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.