| 摘要 |
A method is disclosed of drilling a second well in a formation that contains a first well and has been heated by a heat assisted gravity drainage operation, the method comprising: monitoring the location of the second well using a position sensor having components in the first well; drilling the second well using the drill bit and signals from the position sensor; and cooling the components by supplying coolant through one or more supply lines from a ground surface to the components and returning coolant through one or more return lines from the components to the ground surface; in which one of the first well and the second well is a heat injection well and the other of the first well and the second well is a production well. A position sensor is also disclosed comprising: a housing; a sensor having components within the housing, the sensor being for monitoring the location of a second well during drilling of the second well while the housing is in a first well; one or more coolant supply lines extending between a coolant supply and the components; and one or more coolant return lines extending between the components and a coolant return. |
