William Stewart

Follow

Person

New Pitsligo, GB

People

Patents Grantslast 30 patents

Information Patent Grant
Drill string stabilizer
- Patent number 4,844,179
- Issue date Jul 4, 1989
- Drilex UK Limited
- John Forrest
- E21 - EARTH DRILLING MINING
Information Patent Grant
Directional drilling of a drill string
- Patent number 4,807,708
- Issue date Feb 28, 1989
- Drilex UK Limited and Eastman Christensen Company
- John Forrest
- E21 - EARTH DRILLING MINING
Information Patent Grant
Drop ball sub-assembly for a down-hole device
- Patent number 4,796,704
- Issue date Jan 10, 1989
- Drilex UK Limited
- John Forrest
- E21 - EARTH DRILLING MINING
Information Patent Grant
Drilling using downhole drilling tools
- Patent number 4,775,017
- Issue date Oct 4, 1988
- Drilex UK Limited
- John Forrest
- E21 - EARTH DRILLING MINING