U.S. patent application number 14/022169 was filed with the patent office on 2016-03-17 for apparatuses and methods for cooling sensor components in hot formations.
This patent application is currently assigned to 1669999 Alberta Ltd.. The applicant listed for this patent is 1669999 Alberta Ltd.. Invention is credited to Troy Martin.
Application Number | 20160076339 14/022169 |
Document ID | / |
Family ID | 55454253 |
Filed Date | 2016-03-17 |
United States Patent
Application |
20160076339 |
Kind Code |
A1 |
Martin; Troy |
March 17, 2016 |
APPARATUSES AND METHODS FOR COOLING SENSOR COMPONENTS IN HOT
FORMATIONS
Abstract
A downhole tool, comprising a housing; a sensor having
components within the housing, the sensor being for monitoring a
characteristic of a well; and one or more coolant supply lines
extending to the components. A method comprising: monitoring a
characteristic of a well using a sensor having components within a
housing; and supplying coolant through one or more supply lines to
the components. The methods and apparatuses may be used to drill
steam assisted gravity drainage (SAGD) wells.
Inventors: |
Martin; Troy; (Edmonton,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
1669999 Alberta Ltd. |
Edmonton |
|
CA |
|
|
Assignee: |
1669999 Alberta Ltd.
Edmonton
CA
|
Family ID: |
55454253 |
Appl. No.: |
14/022169 |
Filed: |
September 9, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61698416 |
Sep 7, 2012 |
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Current U.S.
Class: |
166/57 |
Current CPC
Class: |
E21B 47/017
20200501 |
International
Class: |
E21B 36/00 20060101
E21B036/00 |
Claims
1. A downhole tool comprising: a housing enclosing at least a part
of a sensor; one or more coolant supply lines extending to the
housing; one or more coolant return lines extending to the housing;
one or more first channels, formed in the housing and connected to
one of one or more coolant supply lines or one or more coolant
return lines, for bypassing coolant past the at least a part of the
sensor; and one or more second channels, formed in the housing and
connected between the one or more first channels and the other of
the one or more coolant supply lines and the one or more coolant
return lines in the housing, for conveying the coolant to pass over
the at least a part of the sensor; in which the one or more coolant
supply lines and the one or more coolant return lines are
positioned within coiled tubing.
2. A downhole tool, comprising: a housing having a coiled tubing
connector and defining a chamber terminating in an uphole direction
by a ported plate; a sensor having components within the chamber,
the sensor being for monitoring a characteristic of a well; and one
or more coolant supply lines connected to the chamber.
3. The downhole tool of claim 2 in which the one or more coolant
supply lines are connected to the ported plate.
4. The downhole tool of claim 2 further comprising one or more
coolant return lines connected to the ported plate.
5-9. (canceled)
10. A downhole tool comprising: a housing having a chamber defined
by a downhole ported plate and an uphole ported plate in the
housing; a sensor having components within the chamber; and one or
more coolant supply lines extending between a coolant supply,
located above ground in use, and one of the downhole ported plate
or the uphole ported plate.
11. The downhole tool of claim 10 further comprising one or more
coolant return lines extending between a coolant return located
above ground in use and the other of the downhole ported plate or
the uphole ported plate.
12-29. (canceled)
30. A position sensor comprising: a housing; a sensor having
components within the housing, the sensor being for monitoring in
use 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 to the components; and one or more coolant
return lines extending to the components.
31. The position sensor of claim 30 in which the components are
within a chamber defined by the housing and connected to receive
coolant from the one or more coolant supply lines through one or
more ports in a downhole portion of the chamber.
32. The position sensor of claim 31 in which the downhole portion
and an uphole portion of the chamber are each defined by a
respective ported plate mounted within the housing.
33. The position sensor of claim 32 in which the components are
mounted to one or both of the ported plate that defines the
downhole portion of the chamber and the ported plate that defines
the uphole portion of the chamber.
34. The position sensor of claim 30 in which the components are
located within coiled tubing in one of a pair of horizontal wells
used for heat assisted gravity drainage.
35. The position sensor of claim 34 in which the coiled tubing is
coil in coil tubing.
36. The position sensor of claim 30 in which the components
comprise a magnetometer.
37. The position sensor of claim 30 in which monitoring the
location of the second well comprises monitoring the location of a
drill string.
38-75. (canceled)
76. A downhole tool, comprising: a production pump; one or more
coolant supply lines extending to the production pump; and one or
more coolant return lines extending from the production pump.
77. The downhole tool of claim 1 further comprising a temperature
sensor connected to control fluid flow through the one or more
coolant supply lines based on a temperature sensed by the
temperature sensor.
78. The downhole tool of claim 77 in which the temperature sensor
comprises a thermostat valve.
79. (canceled)
Description
TECHNICAL FIELD
[0001] This document relates to systems and methods for cooling
position sensor components while drilling gravity drainage wells in
hot formations.
BACKGROUND
[0002] Wells used in heat assisted gravity drainage (HAGD)
operations must be carefully positioned relative to one another to
maximize production. For example, steam assisted gravity drainage
(SAGD) operations generally use pairs of parallel horizontal wells
(well pairs) aligned with 4-6 meters of vertical separation across
kilometers of well length.
[0003] Position sensors such as magnetometers are used during
drilling to ensure proper positioning of the second well relative
to the first well. Many replacement position sensors may be
required when drilling in a hot formation, such as a formation
previously heated by a steam assisted gravity drainage (SAGD)
operation, because the position sensors have a limited lifespan at
such temperatures. Water may be injected into the formation to cool
the formation and sensors to alleviate the number of replacement
sensors used to drill or to reduce the temperature of the sensors
until they are operating within their temperature
specifications.
[0004] Hot formations are also known to damage downhole wireline
sensors, increasing the cost of a logging operation and well
operation in general. In some cases, sensors may be partially
protected by a heat shield, but eventually a hot formation will
lead to sensor failure. Some sensors are cooled by filling the
wellbore with coolant. Other operations are carried out using a
plurality of sensors, such that once a sensor fails, a new sensor
is inserted and continues the operation until completion.
SUMMARY
[0005] A downhole tool, comprising a housing; a sensor having
components within the housing, the sensor being for monitoring a
characteristic of a well; and one or more coolant supply lines
extending to the components. One or more coolant return lines may
extend to the components.
[0006] A downhole tool is also disclosed comprising a housing
enclosing at least a part of a sensor; one or more coolant supply
lines extending to the housing; one or more coolant return lines
extending to the housing; one or more first channels, formed in the
housing and connected to one of one or more coolant supply lines or
one or more coolant return lines, for bypassing coolant past the at
least a part of the sensor; and one or more second channels, formed
in the housing and connected between the one or more first channels
and the other of the one or more coolant supply lines and the one
or more coolant return lines in the housing, for conveying the
coolant to pass over the at least a part of the sensor; in which
the one or more coolant supply lines and the one or more coolant
return lines are positioned within coiled tubing.
[0007] A downhole tool is also disclosed comprising a housing
having a coiled tubing connector and defining a chamber terminating
in an uphole direction by a ported plate; a sensor having
components within the chamber, the sensor being for monitoring a
characteristic of a well; and one or more coolant supply lines
connected to the chamber.
[0008] A downhole tool is also disclosed comprising a housing
having a coiled tubing connector, and a chamber defined by a
downhole ported plate and an uphole ported plate in the housing; a
sensor having components within the chamber, the sensor being for
monitoring a characteristic of a well; one or more coolant supply
lines extending between a coolant supply and one of the downhole
ported plate or the uphole ported plate; one or more coolant return
lines extending between a coolant return and the other of the
downhole ported plate or the uphole ported plate.
[0009] A downhole tool is also disclosed in a downhole environment
that has a higher temperature than a maximum operating temperature
of the downhole tool, the downhole tool comprising a housing having
a chamber defined by a downhole ported plate and an uphole ported
plate in the housing; a sensor having components within the
chamber, the sensor being for monitoring a characteristic of a
well; one or more coolant supply lines extending to one of the
downhole ported plate or the uphole ported plate; one or more
coolant return lines extending to the other of the downhole ported
plate or the uphole ported plate.
[0010] A downhole tool is also disclosed, comprising a housing
defining a chamber terminated in an uphole direction by a ported
plate; a sensor having components within the housing, the sensor
being for monitoring a characteristic of a well; coil in coil
tubing connected to the chamber and having one or more inner
coolant supply line coils and an outer coolant return annulus.
[0011] A downhole tool is also disclosed, comprising a housing
having a chamber defined by a downhole ported plate and an uphole
ported plate in the housing; a sensor having components within the
housing, the sensor being for monitoring a characteristic of a
well; coil in coil tubing having one or more inner coolant supply
line coils, connected to one of the downhole ported plate and the
uphole ported plate, and an outer coolant return annulus connected
to the other of the downhole ported plate and the uphole ported
plate.
[0012] A downhole tool is also disclosed comprising a housing
having a chamber defined by a downhole ported plate and an uphole
ported plate in the housing; a sensor having components within the
chamber, the sensor being for monitoring a characteristic of a
well; one or more coolant supply lines extending to one of the
downhole ported plate or the uphole ported plate; one or more
coolant return lines extending to the other of the downhole ported
plate or the uphole ported plate; in which the one or more coolant
supply lines and the one or more coolant return lines are
positioned within coiled tubing.
[0013] A downhole tool is also disclosed comprising a housing
having a chamber defined by a downhole ported plate and an uphole
ported plate in the housing; a sensor having components within the
chamber; and one or more coolant supply lines extending between a
coolant supply, located above ground in use, and one of the
downhole ported plate or the uphole ported plate.
[0014] A downhole tool is also disclosed comprising a housing; a
sensor having components within the housing, the sensor being for
monitoring a characteristic of a well; one or more coolant supply
lines to the components; and one or more coolant return lines to
the components; in which the one or more coolant supply lines and
the one or more coolant return lines comprise coil in coil tubing;
and a coolant loop connected to a downhole supply portion of at
least one of the one or more coolant supply lines and to a downhole
return portion of at least one of the one or more coolant return
lines, in which the coolant loop, downhole supply portion, and
downhole return portion are enclosed within the downhole tool.
[0015] A downhole tool is also disclosed comprising a housing
having a chamber defined by a downhole ported plate and an uphole
ported plate in the housing; a sensor having components within the
chamber, the sensor being for monitoring a characteristic of a
well; one or more coolant supply lines to one of the downhole
ported plate and the uphole ported plate; in which the one or more
coolant supply lines comprise coil in coil tubing.
[0016] A downhole tool is also disclosed comprising: a housing
having a chamber terminated in an uphole direction by a ported
plate; a sensor having components within the chamber, the sensor
being for monitoring a characteristic of a well; one or more
coolant supply lines to the chamber; in which the one or more
coolant supply lines comprise coil in coil tubing.
[0017] A downhole tool is also disclosed comprising a housing
having a chamber defined in part by a ported plate; a sensor having
components within the chamber, the sensor being for monitoring a
characteristic of a well; one or more coolant supply lines
extending to the chamber; one or more coolant return lines
extending to the chamber; in which the one or more coolant supply
lines and the one or more coolant return lines are positioned
within coiled tubing.
[0018] A downhole tool is also disclosed comprising a housing
defining a chamber terminated in an uphole direction by a ported
plate and having one or more chamber bypass channels; a sensor
having components within the chamber, the sensor being for
monitoring a characteristic of a well; one or more coolant supply
lines extending to one of the ported plate or the one or more
chamber bypass channels; one or more coolant return lines extending
to the other of the ported plate or the one or more chamber bypass
channels.
[0019] A downhole tool is also disclosed comprising a housing
defining a chamber terminated by a ported plate; a sensor having
components within the chamber, the sensor being for monitoring a
characteristic of a well; and one or more coolant supply lines
extending between a coolant supply, located above ground in use,
and the ported plate; in which the chamber has one or more ports to
an exterior of the downhole tool.
[0020] A downhole tool is also disclosed comprising a housing
enclosing at least a part of a sensor; one or more first channels,
formed in the housing and connected to one or more supply ports in
the housing, for bypassing coolant past the at least a part of the
sensor; and one or more second channels, formed in the housing and
connected between the one or more first channels and one or more
return ports in the housing, for conveying the coolant to pass over
the at least a part of the sensor.
[0021] A downhole tool is also disclosed, comprising a housing
defining a chamber that has a downhole portion and an uphole
portion; a sensor having components within the chamber, the sensor
being for monitoring a characteristic of a well; one or more
coolant supply lines extending between a coolant supply and one or
more ports in one of the downhole portion or the uphole portion of
the chamber; one or more coolant return lines extending between a
coolant return and one or more ports in the other of the uphole
portion or the downhole portion of the chamber.
[0022] A downhole tool, for example within a previously drilled
well, is also disclosed, the downhole tool comprising a housing; a
sensor having components within the housing; one or more coolant
supply lines extending between a coolant supply, located above
ground in use, and the components; one or more coolant return lines
extending between the components and a coolant return located above
ground in use; and in which the one or more coolant supply lines
and the one or more coolant return lines are positioned within
coiled tubing.
[0023] A downhole tool within a previously drilled well is also
disclosed, comprising a housing; a sensor having components within
the housing, the sensor being for monitoring a characteristic of a
well; one or more coolant supply lines extending to the components;
and one or more coolant return lines extending to the components;
in which the one or more coolant supply lines and the one or more
coolant return lines comprise coil in coil tubing.
[0024] A downhole tool is also disclosed, comprising a housing; a
sensor having components within the housing, the sensor being for
monitoring a characteristic of a well; one or more coolant supply
lines extending between a coolant supply and the components; one or
more coolant return lines extending between the components and a
coolant return; and coil in coil tubing, in which the one or more
coolant supply lines and the one or more coolant return lines are
positioned within the coiled tubing.
[0025] A downhole tool is also disclosed, comprising a housing; a
sensor having components within the housing, the sensor being for
monitoring a characteristic of a well; one or more coolant supply
lines extending between a coolant supply, located above ground in
use, and the components; one or more coolant return lines extending
between the components and a coolant return located above ground in
use; the one or more coolant supply lines and the one or more
coolant return lines each comprising coiled tubing; and a coolant
loop connected to a downhole supply portion of at least one of the
one or more coolant supply lines and to a downhole return portion
of at least one of the one or more coolant return lines, in which
the coolant loop, downhole supply portion, and downhole return
portion are enclosed within the downhole tool.
[0026] A downhole tool is also disclosed, comprising a housing; a
logging sensor having components within the housing, the sensor
being for monitoring a characteristic of a well, the logging sensor
being one or more of a bond log sensor, a resurveying logging
sensor, gamma ray logging sensor, a spontaneous potential logging
sensor, a resistivity logging sensor, a density logging sensor, a
sonic logging sensor, a caliper logging sensor, a video camera, and
a nuclear magnetic resonance logging sensor; one or more coolant
supply lines extending to the components; one or more coolant
return lines extending to the components; the one or more coolant
supply lines and the one or more coolant return lines each
comprising coiled tubing; and a coolant loop connected to a
downhole supply portion of at least one of the one or more coolant
supply lines and to a downhole return portion of at least one of
the one or more coolant return lines, in which the coolant loop,
downhole supply portion, and downhole return portion are enclosed
within the downhole tool.
[0027] A downhole tool is also disclosed, comprising a housing; a
sensor having components within the housing, the sensor being for
monitoring a characteristic of a well; one or more coolant supply
lines extending to the components; one or more coolant return lines
extending to the components; a coolant loop connected to a downhole
supply portion of at least one of the one or more coolant supply
lines and to a downhole return portion of at least one of the one
or more coolant return lines, in which the coolant loop, downhole
supply portion, and downhole return portion are enclosed within the
downhole tool; and one or more channels formed in the housing for
bypassing coolant past the components and conveying the coolant to
pass over the components.
[0028] A position sensor is also disclosed comprising a housing; a
sensor having components within the housing, the sensor being for
monitoring in use 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 to the components; and one or more
coolant return lines extending to the components.
[0029] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
housing; and supplying coolant through one or more supply lines
from a coolant supply to the components. The method may include
returning coolant through one or more return lines from the
components to a coolant return.
[0030] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber defined by an uphole ported plate and a downhole ported
plate in a housing; supplying coolant through one or more supply
lines to one of the uphole ported plate or downhole ported plate to
bypass the components and convey the coolant to pass over the
components; and returning coolant from the other of the uphole
ported plate or the downhole ported plate to one or more return
lines.
[0031] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber bounded in an uphole direction by a ported plate; supplying
coolant through one or more supply lines to the chamber to bypass
the components and convey the coolant to pass over the components;
and returning coolant from the chamber to one or more return
lines.
[0032] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber bounded in an uphole direction by a ported plate; supplying
coolant through coiled tubing to the chamber; and returning coolant
from the chamber to one or more coolant return lines.
[0033] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber defined by an uphole ported plate and a downhole ported
plate in a housing; supplying coolant through one or more supply
lines to one of the uphole ported plate or the downhole ported
plate; and returning coolant from the other of the uphole ported
plate and the downhole ported plate to one or more return lines; in
which the well has a higher temperature than a maximum operating
temperature of the sensor.
[0034] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber defined by an uphole ported plate and a downhole ported
plate in a housing; supplying coolant through one or more coolant
supply lines to one of the uphole ported plate and the downhole
ported plate; and returning coolant from the other of the uphole
ported plate and the downhole ported plate to one or more coolant
return lines; in which the one or more coolant supply lines and one
more coolant return lines comprise coiled tubing.
[0035] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber bounded in an uphole direction by a ported plate; supplying
coolant through one or more inner coils of coil in coil tubing to
the chamber; and returning coolant from the chamber to an outer
annulus of the coil in coil tubing.
[0036] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber defined by an uphole ported plate and a downhole ported
plate in a housing; supplying coolant through one or more inner
coils of coil in coil tubing to one of the uphole ported plate and
the downhole ported plate; and returning coolant from the other of
the uphole ported plate and the downhole ported plate to an outer
annulus of the coil in coil tubing.
[0037] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
housing; supplying coolant through one or more supply lines
positioned within coiled tubing to the chamber to bypass the
components and convey the coolant to pass over the components; and
returning coolant from the chamber to one or more return lines
positioned within the coiled tubing.
[0038] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber defined by an uphole ported plate and a downhole ported
plate in a housing; supplying coolant through one or more coolant
supply lines from a coolant supply located above ground to one of
the uphole ported plate and the downhole ported plate; and
returning coolant through one or more coolant return lines from the
other of the uphole ported plate and the downhole ported plate to a
coolant return located above ground.
[0039] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
housing; supplying coolant through one or more coolant supply
lines, positioned within coiled tubing, from a coolant supply
located above ground to the components; and returning coolant
through one or more coolant return lines, positioned within the
coiled tubing, from the components to a coolant return located
above ground.
[0040] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
housing; supplying coolant through one or more coolant supply
lines, positioned within coil in coil tubing, from a coolant supply
to the components; and returning coolant through one or more
coolant return lines, positioned within the coil in coil tubing,
from the components to a coolant return.
[0041] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber defined by an uphole ported plate and a downhole ported
plate in a housing; supplying coolant through one or more coolant
supply lines from a coolant supply to one of the uphole ported
plate and the downhole ported plate; and returning coolant through
one or more coolant return lines from the other of the uphole
ported plate and the downhole ported plate to a coolant return; in
which the one or more coolant supply lines and the one or more
coolant return lines comprise coil in coil tubing.
[0042] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber defined by an uphole ported plate and a downhole ported
plate in a housing; supplying coolant through one or more coolant
supply lines, positioned within coiled tubing, to one of the uphole
ported plate and the downhole ported plate; and returning coolant
through one or more coolant return lines, positioned within coiled
tubing, from the other of the uphole ported plate and the downhole
ported plate.
[0043] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber bounded in an uphole direction by a ported plate; supplying
coolant through one or more coolant supply lines to the chamber;
and returning coolant through one or more coolant return lines from
the chamber; in which the one or more coolant supply lines and the
one or more coolant return lines comprise coil in coil tubing.
[0044] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber bounded in an uphole direction by a ported plate; supplying
coolant through one or more coolant supply lines, positioned within
coiled tubing, to the chamber; and returning coolant through one or
more coolant return lines, positioned within coiled tubing, from
the chamber.
[0045] A method is also disclosed comprising monitoring a
characteristic of a well used for heat assisted gravity drainage
using a sensor having components within a housing; and supplying
coolant through one or more supply lines from a coolant supply to
the components; and returning coolant through one or more return
lines from the components to a coolant return.
[0046] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
housing connected to a tubing string; and switching between a first
mode and a second mode; in which the first mode comprises supplying
coolant to the components through one or more supply lines to the
components, and returning coolant through one or more return lines
from the components; in which in the second mode coolant is
supplied to the components through the one or more supply lines and
the one or more return lines and returned up the tubing string.
[0047] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
housing; and supplying coolant through one or more supply lines
from a coolant supply to bypass the components; supplying the
coolant to pass over the components; and returning coolant through
one or more return lines from the components to a coolant
return.
[0048] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
coolant loop within a downhole tool; and supplying coolant to the
coolant loop through a downhole supply portion of one or more
supply lines; and returning coolant from the coolant loop through a
downhole return portion of one or more return lines; in which the
coolant loop, downhole supply portion, and downhole return portion
are enclosed within the downhole tool; in which the one or more
coolant supply lines and the one or more coolant return lines
comprise coil in coil tubing.
[0049] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
coolant loop within a downhole tool; and supplying coolant through
one or more supply lines from a coolant supply to bypass the
components and convey the coolant to pass over the components; and
returning coolant from the coolant loop through a downhole return
portion of one or more return lines; in which the coolant loop,
downhole supply portion, and downhole return portion are enclosed
within the downhole tool.
[0050] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
coolant loop within a downhole tool; and supplying coolant from a
coolant supply located above ground to the coolant loop through a
downhole supply portion of one or more supply lines; and returning
coolant from the coolant loop through a downhole return portion of
one or more return lines to a coolant return located above ground;
in which the coolant loop, downhole supply portion, and downhole
return portion are enclosed within the downhole tool; in which the
one or more coolant supply lines and the one or more coolant return
lines comprise coiled tubing.
[0051] A method is also disclosed comprising monitoring a
characteristic of a previously drilled well using a sensor having
components within a housing; and supplying coolant through one or
more supply lines to the components; and returning coolant through
one or more return lines from the components; in which the one or
more coolant supply lines and the one or more coolant return lines
comprise coil in coil tubing.
[0052] A method 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
signals from the position sensor; 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.
[0053] A method is also 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
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.
[0054] A position sensor is also disclosed comprising a housing,
for example made of one or both of ferrous or non ferrous material;
a sensor having components within the housing, the sensor being for
monitoring the location of a second well while 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.
[0055] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
chamber bounded by a ported plate; supplying coolant through one or
more coolant supply lines to the chamber; and discharging coolant
through one or more ports in the chamber to an exterior of the
downhole tool.
[0056] A method is also disclosed comprising monitoring a
characteristic of a well using a sensor having components within a
housing; supplying coolant through one or more coolant supply lines
to the housing from a coolant supply located above ground; and
discharging coolant through one or more ports in the housing for
return up the wellbore.
[0057] A downhole tool is also disclosed comprising a housing; a
sensor having components within the housing, the sensor being for
monitoring a characteristic of a well; and one or more coolant
supply lines extending between a coolant supply, located above
ground in use, and the chamber; in which the one or more coolant
supply lines comprise coiled tubing connected to the housing.
[0058] A downhole tool and method of use is also disclosed
comprising a housing enclosing at least a part of a tool component;
one or more coolant return lines at least a portion of which is
extended to the housing; and one or more coolant supply lines
including at least a first portion and a second portion, the first
portion being extended to the housing, the second portion being
extended, at a point uphole of the housing, to the one or more
coolant return lines.
[0059] A downhole tool and method of use is also disclosed,
comprising a tool component such as a production pump; one or more
coolant supply lines extending to the production pump; and one or
more coolant return lines extending from the production pump. All
embodiments in this disclosure that include sensors may be adapted
to incorporate a tool component in place or in addition to the
sensor.
[0060] In various embodiments, there may be included any one or
more of the following features: The one or more coolant supply
lines extend to a coolant supply. One or more coolant return lines
extend to the components. The one or more coolant return lines
extend to a coolant return. The chamber terminates or is bound in
an uphole direction by a ported plate. The one or more coolant
supply lines extend between a coolant supply and one of the
downhole ported plate or the uphole ported plate. The one or more
coolant return lines extend between a coolant return and the other
of the downhole ported plate or the uphole ported plate. The
chamber has one or more ports to an exterior of the downhole tool.
The housing has a coiled tubing connector. The chamber has one or
more chamber bypass channels. The well has a higher temperature
than the maximum operating temperature of the downhole tool. The
components of the position sensor are contained within coiled
tubing. The coiled tubing is coil in coil tubing. The one or more
supply lines are defined by one or more inner coils of the coil in
coil tubing, and the one or more return lines are defined by one or
more inner coils of the coil in coil tubing. The one or more supply
lines are defined by one or more inner coils of the coil in coil
tubing, and the one or more return lines are defined by an outer
annulus of the coil in coil tubing. The first well and the second
well are a parallel well pair. The first well and the second well
are an intersecting well pair. Drilling the second well further
comprises advancing the components towards a toe end of the first
well. The first well and the second well are horizontal wells. The
position sensor comprises a magnetometer. The components comprise
the magnetometer. Carrying out a heat assisted gravity drainage
operation, such as a SAGD operation, using the first well and the
second well. The components are within a chamber defined by the
housing and connected to receive coolant from the one or more
coolant supply lines through one or more ports in a downhole end of
the chamber. The downhole end and an uphole end of the chamber are
each defined by a respective ported plate mounted within the
housing. The components are mounted to one or both of the ported
plate that defines the downhole end of the chamber and the ported
plate that defines the uphole end of the chamber. The components
are located within coiled tubing, for example fixed to the end of
the coiled tubing, in one of a pair of horizontal wells used for
heat assisted gravity drainage. The one or more coolant supply
lines and the one or more coolant return lines comprise coiled
tubing. The coiled tubing comprises coil in coil tubing. The one or
more coolant supply lines comprise one or more inner coils of the
coil in coil tubing. The one or more coolant return lines comprise
an outer annulus of the coil in coil tubing. The one or more
coolant return lines comprise one or more inner coils of the coil
in coil tubing. The one or more coolant supply lines are positioned
within the coiled tubing. The one or more coolant return lines are
positioned within the coiled tubing. A coolant loop is connected to
a downhole supply portion of at least one of the one or more
coolant supply lines and to a downhole return portion of at least
one of the one or more coolant return lines, in which the coolant
loop, downhole supply portion, and downhole return portion are
enclosed within the downhole tool. The coolant supply is located
above ground in use. The coolant return is located above ground in
use. The components are within a chamber in the housing, the
chamber having a downhole portion and an uphole portion. The one or
more coolant supply lines are connected to supply fluid through one
or more ports in the downhole portion of the chamber. The one or
more coolant return lines are connected to return fluid through one
or more ports in the uphole portion of the chamber. The downhole
portion and the uphole portion of the chamber are each defined by
respective ported plates mounted within the housing. The components
are mounted to one or both of the ported plate that defines the
downhole portion of the chamber and the ported plate that defines
the uphole portion of the chamber. The housing is in one of a pair
of horizontal wells used for heat assisted gravity drainage. The
sensor is a position sensor. The position sensor is for monitoring
the location of a second well during drilling of the second well
while the housing is in a first well. The downhole tool is
positioned within a previously drilled well. The sensor is a
logging sensor. The logging sensor comprises one or more of a bond
log sensor, a resurveying logging sensor, gamma ray logging sensor,
a spontaneous potential logging sensor, a resistivity logging
sensor, a density logging sensor, a sonic logging sensor, a caliper
logging sensor, a video camera, and a nuclear magnetic resonance
logging sensor. Channels are formed in the housing for bypassing
coolant past the components and conveying the coolant to pass over
the components; and a coiled tubing connector is in the housing,
the coiled tubing connector having ports communicating with the
channels to provide coolant supply and coolant return. The channels
comprise: one or more first channels, formed in the housing and
connected to one or more supply ports in the housing, for bypassing
coolant past the at least a part of the sensor; and one or more
second channels, formed in the housing and connected between the
one or more first channels and one or more return ports in the
housing, for conveying the coolant to pass over the at least a part
of the sensor. The housing comprises a coiled tubing connector
having ports communicating with the one or more first channels and
the one or more second channels to provide coolant supply and
coolant return. The downhole portion and the uphole portion of the
chamber are each defined by a respective ported plate mounted
within the housing. The components are within a chamber defined by
the housing and connected to receive coolant from the one or more
coolant supply lines through one or more ports in a downhole
portion of the chamber. The downhole portion and an uphole portion
of the chamber are each defined by a respective ported plate
mounted within the housing. The components are mounted to one or
both of the ported plate that defines the downhole portion of the
chamber and the ported plate that defines the uphole portion of the
chamber. Monitoring the location of the second well comprises
monitoring the location of a drill string. Switching between: a
first mode where coolant is supplied through the one or more supply
lines and returned through the one or more return lines; and a
second mode where coolant is supplied through the one or more
supply lines and the one or more return lines and returned up the
coiled tubing. The coolant is returned up the annulus of the coiled
tubing in the second mode. The housing is part of a downhole tool,
and further comprising a coolant loop connected to a downhole
supply portion of at least one of the one or more coolant supply
lines and to a downhole return portion of at least one of the one
or more coolant return lines, in which the coolant loop, downhole
supply portion, and downhole return portion are enclosed within the
downhole tool. Drilling a second well, in which monitoring further
comprises monitoring the location of the second well during
drilling of the second well while the housing is in a first well.
The components are positioned within a previously drilled well.
Monitoring further comprises logging. Supplying comprises bypassing
coolant past the components and conveying the coolant to pass over
the components. Coolant bypasses the components before being
conveyed to pass over the components. The one or more supply lines
are defined by one or more inner coils of the coil in coil tubing,
and the one or more return lines are defined by one or more inner
coils of the coil in coil tubing. The one or more supply lines are
defined by one or more inner coils of the coil in coil tubing, and
the one or more return lines are defined by an outer annulus of the
coil in coil tubing. A temperature sensor is connected to control
fluid flow through the one or more coolant supply lines based on a
temperature sensed by the temperature sensor. The temperature
sensor comprises a thermostat valve. The temperature sensor is at
least partially within the housing. The thermostat valve is
connected to open between the housing and the well bore at sensed
temperatures above a predetermined temperature.
[0061] These and other aspects of the device and method are set out
in the claims, which are incorporated here by reference.
BRIEF DESCRIPTION OF THE FIGURES
[0062] Embodiments will now be described with reference to the
figures, which are not to scale, in which like reference characters
denote like elements, by way of example, and in which:
[0063] FIG. 1 is a side elevation view, partially in section, of a
coil in coil tubing rig being used to supply and return coolant to
a position sensor in a production well while an injector well is
being drilled.
[0064] FIG. 2 is a side elevation view, partially in section, of a
position sensor contained in a housing with a sensor chamber, and
with arrows illustrating coolant fluid movement through the
housing.
[0065] FIG. 3 is a side elevation section view of a position sensor
that has two coolant supply lines.
[0066] FIG. 4 is a section view taken along the 4-4 section lines
from FIG. 3.
[0067] FIG. 5 is a side elevation section view of a position sensor
that has one coolant supply line.
[0068] FIGS. 6 and 7 are side elevation views illustrating uphole
and downhole port assemblies, respectively, for use with the
position sensors of FIGS. 8 and 9.
[0069] FIG. 8 is a side elevation section view of another
embodiment of a position sensor that has a single coolant supply
line.
[0070] FIG. 9 is a side elevation section view of another
embodiment of a position sensor that has a plurality of coolant
supply lines.
[0071] FIG. 10 is a section view taken along the 10-10 section
lines from FIGS. 6 and 7.
[0072] FIG. 11 is a section view taken along the 11-11 section
lines from FIGS. 6 and 7.
[0073] FIG. 12 is an exploded view of the embodiment of FIG. 3 with
the supply and return lines removed for clarity.
[0074] FIGS. 13-18 are section views taken along the 13-13, 14-14,
15-15, 16-16, 17-17, and 18-18 section lines, respectively, shown
in FIG. 12.
[0075] FIG. 19 is a perspective view of an exemplary valve and line
arrangement for switching modes as described below.
[0076] FIGS. 20A-C are a side perspective view, partially in
section (FIG. 20A), a section view taken along the 20B-20B section
lines of FIG. 20A (FIG. 20B), and a top plan view, partially in
section (FIG. 20C), of an embodiment of the apparatus housing a
sonic tool.
[0077] FIG. 21 is a side elevation view of an embodiment of a
downhole caliper tool.
[0078] FIG. 22 is a side elevation view of an embodiment of a
downhole resistivity tool.
[0079] FIG. 23 is a side elevation view, partially in section, of a
downhole video camera tool.
[0080] FIG. 24 is a side elevation view, partially in section, of a
downhole tool that supplies a portion of the coolant to the housing
and a portion to the return lines.
DETAILED DESCRIPTION
[0081] Immaterial modifications may be made to the embodiments
described here without departing from what is covered by the
claims.
[0082] Steam-assisted gravity drainage (SAGD) is a
hydrocarbon-producing process that is used to extract viscous
hydrocarbons from hydrocarbon-producing reservoirs located under
the ground surface. Conventional methods of hydrocarbon extraction,
such as mining and/or drilling are generally ineffective or
inefficient at extracting viscous hydrocarbons such as bitumen,
crude oil, or heavy oil, and thus SAGD and other heat-assisted
gravity drainage (HAGD) methods are used to add heat to the
hydrocarbons to lower their viscosity to a point where they may be
collected in a well for production. Examples of the type of
hydrocarbon-producing reservoirs that contain these viscous
hydrocarbons include oil sands located primarily in Canada and
Venezuela.
[0083] The injection and production wells may be horizontally
drilled wells that extend distances of several kilometers from
heel-to-toe. Steam is injected into the reservoir along at least a
portion of the length of the injection well, permeating the
formation and forming a steam chamber throughout the reservoir
around the injection well. In some cases other suitable species may
be injected other than or in addition to steam, including heated
solvent in the case of vapor extraction (VAPEX) or air in the case
of toe heel air injection (THAI). Viscous hydrocarbons contained
within the steam chamber are heated and reduce in viscosity enough
to drain by gravity into the production well, where they are pumped
to the surface. This process allows viscous hydrocarbons contained
within large, relatively horizontal reservoirs under the ground
surface to be effectively extracted.
[0084] FIG. 1 illustrates a horizontal well pair used for steam
assisted gravity drainage (SAGD) operations. In some cases the
methods disclosed herein may be carried out intersecting wells. The
well pair comprises a production well 10 and an injection well 12
above the production well 10. There are no requirements as to which
of wells 10 and 12 should be drilled first, but in the example
shown the lower production well 10 is drilled first. In some cases
the wells 10 and 12 may be drilled simultaneously although one of
the wells may be concurrently drilled ahead of the other.
[0085] SAGD wells may be shallow, and a slant rig (not shown) may
be employed to drill the wells a few hundred meters deep. With a
slant rig, the drill pipe enters the ground at an angle of about
45.degree. angle, so that the well can build quickly to 90.degree.,
i.e. horizontal. After being drilled in the desired zone, the first
well 14, in this case production well 10, may be cased, for example
with slotted or perforated liner (not shown) for stability. In
other cases, SAGD wells may be drilled from a vertical well.
[0086] Once the user is ready to drill the second well 16, in this
case injection well 12, a wireless or wireline tool such as
position sensor 18 described below may be deployed inside the
tubing of first well 14. Such a tool is used because the relative
distance between the injector and production wells may affect
potential recovery. The wells should be located sufficiently near
to one another such that heavy oil heated at the injector well may
drain into the production well. If the wells are located too near
to one another, steam or air from the injector well may shunt into
the production well, and if the wells are located too far from one
another, the heated heavy oil may not extend to the production
well.
[0087] The wireline tool determines the location of second well 16
relative to first well 14. This information is then used to steer
the second well 16 parallel or within sufficient proximity to first
well 14. The bottom hole assembly 20 in second well 16 may include
a steering mechanism (not shown), such as a steerable motor with
bent sub or a rotary steerable system, for steering a drill bit 22.
Position sensor 18 may use measurement while drilling technology
such as magnetic ranging or nuclear ranging. There are several
magnetic ranging techniques that may be used, including active and
passive ranging.
[0088] Active techniques generally involve the production of a
magnetic field in the first well 14 or second well 16, followed by
detection in the other of wells 14 or 16 by a sensor such as a
magnetometer. For example, the tool 18 may contain a solenoid (not
shown) that produces a magnetic field, with known strength and
field pattern, that is then detected by a sensor (not shown) in the
second well 16. The tubing and slotted casing may affect the
magnetic field but these effects can be removed by calibrating the
solenoid inside the same size tubing and casing on the surface. The
magnitude of the measured magnetic field indicates the separation
of the two wells 10, 12 and the direction of the magnetic field
indicates their relative positions. In another example, the second
well 16 generates the magnetic field using one or more permanent
magnets mounted in a near-bit sub (not shown), or on the mud motor
(not shown) in some cases. The permanent magnets rotate with the
drill bit 22 thus producing an oscillating magnetic field that is
detected by a magnetometer in the position sensor 18 as the drill
bit 22 passes by the position sensor 18. The distance between the
wells 14, 16 is deduced from the variation in the magnetic field
with measured depth of the drill bit. In yet another example of an
active technique, a wire (not shown) is used in first well 14 to
carry a current to the toe 24 of first well 14 where the wire is
grounded to the casing 26. Most of the current returns to the
surface through the casing 26 but a small amount of current leaks
into the formation 28 at each foot along its length. The leakage
current varies from foot to foot depending on the properties of the
casing, the cement, and the formation resistivity. The net current
produces an azimuthal magnetic field around the wellbore that can
be measured with a magnetometer in the second well 16. Other
sensors and sensing techniques may be used.
[0089] Passive ranging techniques are generally less effective than
active techniques. For example, permanent magnets may be installed
inside the steel casing and alternately magnetized N-S and S-N to
create a discernable magnetic field pattern. The magnetic field is
measurable within the second well 16 and the information employed
to steer drill bit 22. Afterwards, the permanent magnets may be
recovered from the cased well.
[0090] Once a SAGD field is up and running, the formation 28 may be
pumped with heat for a suitable amount of time, such as years.
Often a single formation 28 will be injected with heat from plural
well pairs, in order to heat the entire formation. However, a user
may desire for a variety of reasons to drill additional wells in
the formation 28 after heating. For example, a user may want to
re-drill an injection well to replace an existing injection well
that is not properly aligned with the corresponding production
well, or to replace an injection well that has been damaged. In
other cases, a user may desire to place an additional well pair at
a location in the formation 28 where the steam chamber has not
adequately penetrated. A user may also simply wish to provide a
denser matrix of well pairs in order to facilitate maximum draw
from the formation 28. In some cases a wedge well may be
drilled.
[0091] Components used in the position sensors described above are
generally electrical components and include microprocessors,
accelerometers, magnetomers, or transducers for example. A
limitation on the use of such components may be the high
temperatures that are often present and associated with a formation
28 made hot from the SAGD process. Downhole ambient temperatures
can approach those of saturated steam and many electrical
components that are commercially available cannot operate reliably
with such conditions.
[0092] As a result of the temperature limitations on these tools,
drilling wells in such hot formations 28 is made more difficult
than conventional drilling of these wells. For example, one
approach taken is to have in stock a plurality of replacement
position sensors that are used one at a time in the first well 14
until inevitable failure of the sensor. Upon failure, the old
sensor is withdrawn and a new sensor is inserted. This process is
continued until the second well 16 is drilled. This approach is
expensive because it requires the purchase of a plurality of
replacement sensors, as well as the additional labor and tool
rental time required to change out and calibrate each new sensor.
This approach may not be possible in wells that are above a certain
temperature.
[0093] Another approach is to cool off the formation 28 in the
vicinity of the first well 14. This approach involves the injection
into first well 14 of coolant such as water. Again, this approach
is also expensive for various reasons. Firstly, it requires large
amounts of water, due to the large volume of formation 28 that must
be cooled, and due to other factors such as non uniform dispersal
into the formation resulting in lingering hot spots that can only
be cooled by continual pumping of coolant. Most or all of the
injected water must then be recovered and removed from produced
bitumen once operations begin again. Secondly, the injected water
cools the formation, meaning that SAGD operations cannot be
immediately resumed after the well 16 is drilled because the
formation 28 temperature must be raised again by additional and
costly steam injection. In addition, the heat plants supplying
steam to the formation 28 must be shut down months in advance in
order to assist this method. It generally takes months after
drilling to get the temperature back up to sufficient levels.
Thirdly, this approach imparts a temperature shock on the casing of
the first well sufficient to strain and sometimes damage the
casing, which may be difficult or impossible to repair.
[0094] Referring to FIG. 1, a method of drilling a second well 16
in a formation 28 that contains a first well 14 and has been heated
by a heat assisted gravity drainage operation is illustrated. In
the example shown the second well 16 is the upper injector well 12,
but this orientation may be reversed and the second well 16 may be
the production well 10. The location of the second well 16 is
monitored using a position sensor 18 having components 30 in the
first well 14. The location of the second well 16 may be indirectly
monitored by monitoring the position of the drill bit 22 or the
drill string.
[0095] The second well 16 is drilled using the drill bit 22 and
signals from the position sensor 18. Such signals may be used in
various ways in order to aid in the steering of drill bit 22. In
one example, the signals are routed to a controller (not shown)
that is set to automatically steer drill bit 22 in order to achieve
a predetermined distance and alignment with the first well 14. In
another example, the signals are sent wirelessly or by wire to a
console (not shown) where a user interprets the signals or data
from the signals in order to manually guide steering of the drill
bit 12.
[0096] Referring to FIGS. 1 and 2, the components 30 are cooled by
supplying coolant through one or more supply lines 32 from a ground
surface 36 to the components 30 and returning coolant through one
or more return lines 34, such as a coil annulus, from the
components to the ground surface 36. FIG. 2 illustrates an
exemplary position sensor 18 in greater detail than shown in FIG.
1. Position sensor 18 has a housing 54, components 30 of a sensor
56, one or more coolant supply lines 32 and one or more coolant
return lines 34. Components 30 are located within housing 54 (FIG.
1), the sensor 56 being for monitoring the location of a drill bit
22 (FIG. 1) during drilling of second well 16 while the housing or
flask 54 is in first well 14.
[0097] The components 30 contained within housing 54 may include a
magnetometer as sensor 56. Other components 30 may be used, such as
accelerometers, e-magnets, transducers, wired or wireless
transmitters and receivers, and other suitable electronic
components. In some cases components 30 may include a magnetic
field generator (not shown) instead of a magnetometer. In this
case, the position sensor 18 may incorporate other components, such
as a magnetometer, that are to be located during drilling in the
second well 16. In general when components are mounted in the
second well 16, such components may be sufficiently cooled by
drilling fluid and may not require a coolant system such as the one
used in first well 14 described herein.
[0098] Referring to FIG. 2, the components 30 may be housed within
a chamber 58 defined by the housing 54. Chamber 58 may be connected
to receive coolant from the one or more coolant supply lines 32
through one or more ports 60 in a downhole portion, such as
downhole end 62 of the chamber 58. The components 30 may be
immersed in coolant in use. The downhole portion and an uphole
portion, such as uphole end 64 of the chamber 58 may be each
defined by ported plates 66 and 68, respectively, mounted within
the housing 54. As shown, the components 30 may be mounted to one
or both downhole ported plate 66 and uphole ported plate 68.
Housing 54 may be designed to allow the one or more supply lines 32
to bypass components 30 in a downhole direction 72, so that coolant
from the one or more supply lines 32 may then reverse direction and
wash over components 30 in an uphole direction 74. Thus, the
portion of components 30 that are situated furthest downhole
receive the coolest of coolant supply fluid. This direction of flow
may be reversed. The lines 32 and 34 may be oriented as shown to
ensure that fluid is circulated through the chamber 58 in one
direction only, in this case from downhole end 62 to uphole end 64.
Such a circulation loop reduces the possibility of stagnant coolant
being retained and overheated in chamber 58 as may occur if fluid
were directly supplied to and removed from chamber 58 from the same
ported plate. The supply lines 32 may supply coolant to chamber 58
by passing through one or more ports 60 of ported plate 66 into a
secondary chamber 76 downhole of the chamber 58, and then reversing
direction and entering the chamber 58 by passing through one or
more ports 60 in the same ported plate 66 as shown. In other
embodiments, ported plate 66 is a manifold that combines plural
supply lines 32 and directly supplies fluid to chamber 58. A
wireline 70 may be used to communicate signals between components
30 and ground surface 36 (FIG. 1).
[0099] Coiled tubing may be used with the methods and apparatuses
disclosed herein. For example, the one or more supply lines and the
one or more return lines may comprise coiled tubing as shown. The
example in FIG. 1 illustrates a coiled tubing rig 38 used to
contain and position the components 30 of the position sensor 18
within coiled tubing 40, in this case coil in coil tubing. Coiled
tubing has an advantage of allowing the position sensor 18 to be
precisely repositioned in an inclined well such as a directional or
horizontal well without requiring additional components. Coiled
tubing also allows the coolant to be enclosed within the downhole
tool. For example, the injection rate of coiled tubing 40 at rig 38
may be controlled to advance the components 30 towards a toe end 24
of the first well 14 at the desired rate and temperature without
dumping unwanted fluid in the well bore. By contrast, conventional
wireline sensors may require additional components such as tractors
or hydraulic tubing to reposition the sensors in a directional or
horizontal well.
[0100] As shown in FIG. 1, coil in coil tubing 40 may be used to
contain the components 30 of position sensor 18. The one or more
supply lines 32 may comprise, for example be defined directly or
indirectly by, one or more inner coils 42 of the coil in coil
tubing. The one or more return lines 34 may comprise, for example,
be defined at least in part by, an outer annulus 44 of the coil in
coil tubing. One or more coolant return lines 34 may comprise, for
example, be defined at least in part by, one or more inner coils 42
(FIG. 5) of the coil in coil tubing. In some cases, one or both of
lines 32 and 34 are positioned within coiled tubing 40, for example
if lines 32 or 34 are tubulars positioned within the coiled tubing
40. Such tubulars may be made of the same or different material as
the coiled tubing. Pumping return coolant up the annulus provides a
shielding effect to coolant being supplied through the supply lines
32, because the return coolant insulates the supply coolant from
heat from the formation 28. This effect will be realized to some
extent with the use of a return line 34 in general. In the example
shown, a pump 46 may be used to pump coolant from a coolant supply
such as a reservoir 48, down supply line 32 to components 30, up
return line 34, and into a coolant return such as a reservoir 52 at
ground surface 36. A pump (not shown) may also be used on the
return line 34. In some embodiments, the one or more supply lines
32 are defined by one or more inner coils of the coil in coil
tubing, and the one or more return lines 34 are defined by one or
more inner coils of the coil in coil tubing. Reservoirs 48 and 52
may be independent, linked, or may be the same reservoir in some
cases. A cooling system (not shown) may be used to cool reservoir
fluid. In some cases the heated coolant may be used to heat a
device or structure such as a building above ground. Coolant may be
recycled by these or other methods. Although coil in coil tubing is
illustrated by concentric coil in coil tubing, other coil in coil
tubing may be used, such as coil in coil tubing with plural inner
tubes.
[0101] Referring to FIGS. 3-5 embodiments of a position sensor 18
are illustrated that have a single supply line 32 (FIG. 5) or
plural supply lines 32 (FIG. 3). Supply and return lines 32 and 34,
respectively, may run along the entire length of the coiled tubing.
Other numbers of lines 32 or 34 may be used. In both FIGS. 3 and 5,
each supply line 32 passes through a series of ported plates 78 en
route to secondary chamber 76 at the end of the sensor 18. Each
line 32 may be secured within a port 60 in the ported plates 78 by
a suitable mechanism such as one or more set screws 80. Gaskets
(not shown) such as O-rings may be used to seal the space between
each plate 78 and each line 32. In the multi supply example of
FIGS. 3 and 4, two supply lines 32 provide coolant to chamber 76,
which then supplies coolant to sensor chamber 58 through two open
ports 61 in the two most downhole plates 79. Coolant is then
returned from chamber 58 up the annulus 44 and around supply lines
32 within coiled tubing 40. In the single supply example of FIG. 5,
supply line 32 supplies coolant to chamber 76 through the most
downhole plate 81 shown, which then supplies coolant to chamber 58
through ports 63 in the two most downhole plate 81 and 83. Coolant
leaves chamber 58 through return line 34, which connects to chamber
58 through another port 65 in the plate 85 that defines the uphole
end 81 of chamber 58 as shown. Plate 87 is the most uphole plate in
the system shown.
[0102] FIGS. 6-11 show various parts that make up the chamber 58 in
another embodiment of a position sensor 18 housing 54. FIGS. 6 and
7 illustrate the uphole and downhole ported plate assemblies 82,
84, respectively. The uphole manifold 82 may have a pin 90 and the
downhole assembly 84 may have a box 92 for mounting the components
30 (not shown) within chamber 58 (not shown) when the tool is
assembled. Pin 90 and box 92 may be part of a tubular 91 provided
for housing one or more wirelines 70 (shown in FIG. 2) for
operating sensors 18 or 19. FIGS. 10 and 11 illustrate the two
types of ported plates 86 and 88 used in both assemblies 82, 84.
FIGS. 8 and 9 illustrate the assemblies 82 and 84 connected to give
a single supply embodiment (FIG. 8) and a plural supply embodiment
(FIG. 9).
[0103] A test was carried out using a housing 54 at the end of two
1900 meters of coiled one way coolant line within a steam truck.
Thus, there was no return line washing over the coil as would be
present in the examples shown in the drawings. The removal of the
return line represents a worst case scenario, i.e. if the return
line 34 failed in a real life application of using the tool. Steam
was injected into the apparatus until all the components reached a
temperature above 240.degree. C. The temperature was held at
240.degree. C. for two hours before coolant was pumped into both
coils at a combined flow rate of 19 liters/minute (0.019 cubic
meters/min) and 1145 psi. The temperature of the tool dropped below
the target temperature of 120.degree. C. Note that the flow rate
can be brought up substantially by adding additional coolant. In a
downhole environment the returning fluid would add an additional
barrier insulating the injection fluid from the formation
temperature. This test illustrated that the sensors could be
adequately cooled using a fraction of the amount of water used
previously to cool down the formation, even if the coolant did not
return to the surface.
[0104] A well pair may originate from two separate mother wells, or
from a single multilateral mother well to reduce environmental
impact. A magnetometer may be a three axis magnetometer, which
allows the direction of the second well 16 to the casing to be
deduced from the three orthogonal components of the magnetic field.
A heat shield (not shown) may be provided when a gyro tool is used.
Although described above for use in drilling horizontal SAGD well
pairs, the methods and apparatuses can be used for other HAGD
methods that require precise positioning of one well next to
another, for example cross SAGD (X-SAGD), THAI, and VAPEX methods.
More than one sensor or component may be carried within the housing
54. The housing 54 may be threaded or otherwise modified so as to
allow the coupling of additional lengths of housing 54 that have a
similar thread or coupling modification, to increase or decrease
the length of chamber 58. The housing 54 may be threaded or
otherwise modified so as to allow coupling with a coiled tubing
drill string, drill pipe or well bore tractor. The number of supply
and return lines do not need to be equal, and include one, two, or
a plurality of lines. The coolant does not need to directly contact
the components 30, but may indirectly cool the components 30 by
passing sufficiently adjacent the components 30. Suitable coolants
may be used, including water, nitrogen, propane, hydrocarbons, and
other suitable fluids, including gases or liquids. The plates 66
and 68 may centralize the components 30 within chamber 58. The
temperature in the chamber 58 may be monitored directly or
indirectly and a coolant characteristic such as flow or coolant
temperature adjusted in order to maintain the chamber 58 within a
predetermined range of temperatures. The actual sensor may be
located in the second well, while other related components are
located within the first well. One, two, or a plurality of ports
may be provided in each ported plate. Each part of tool 94 may be
provided in two or more pieces such as plural sleeves connected
together.
[0105] Referring to FIGS. 1 and 2, further examples of the general
concept of the methods and apparatuses disclosed herein will now be
described. The general concept is not limited to position sensors
or drilling, and may be used in a variety of applications.
[0106] For example, a downhole tool 94 is shown in FIG. 2 as having
a housing 54, and a sensor 19, such as a position sensor 18 (FIG.
2). Sensor 19 may have components 30 at least partially within the
housing 54, for example within chamber 58. The sensor 19 may be
provided for monitoring a characteristic of a well 26 (FIG. 1).
Tool 94 may also have one or more coolant supply lines 32. Tool 94
may have one or more coolant return lines 34. Lines 32 may extend
between a coolant supply 48 (FIG. 1) and the components 30, and
lines 34 may extend between the components 30 and a coolant return
52 (FIG. 1).
[0107] A coolant loop 97 is shown connected to a downhole supply
portion 98 of at least one of the one or more coolant supply lines
32 and to a downhole return portion 99 of at least one of the one
or more coolant return lines 34 (FIG. 2). The coolant loop 97,
downhole supply portion 98, and downhole return portion 99 may be
enclosed within the downhole tool 94.
[0108] The downhole tool 94 may be positioned within a previously
drilled well, such as well 26, an existing well, a cased well, a
completed well, a production well, an injection well (FIG. 1), and
other suitable wells. The tubing string connected to housing 54 may
not terminate in a drill bit (not shown) in some cases. The sensor
19 (FIG. 2) may be a logging sensor, such as one or more of a bond
log sensor, a resurveying logging sensor, gamma ray logging sensor,
a spontaneous potential logging sensor, a resistivity logging
sensor, a density logging sensor, a sonic logging sensor, a caliper
logging sensor, and a nuclear magnetic resonance logging sensor.
Some sensors may be one or both of positioned partly outside of
chamber 58 (FIGS. 21 and 22, discussed further below), or in fluid
contact with the exterior wellbore, for example in the case of a
sonic logging sensor (FIG. 20A, discussed further below).
[0109] Channels, such as one or more first channels 100 and one or
more second channels 102, may be formed in the housing 54 for
bypassing coolant past the components 30 and conveying the coolant
to pass over the components 30 (FIG. 2). A coiled tubing connector
104 may be present in the housing 54, the coiled tubing connector
104 having ports 60 communicating with the channels 100 and 102 to
provide coolant supply and coolant return. Channels 100 may bypass,
and channels 102 may convey coolant, in which the channels 100 are
connected to the one or more supply lines 32 and channels 102 are
connected between channels 100 and the one or more return lines 34.
Channels 100 and 102 may house parts of lines 32 and 34,
respectively, and may include one or more of ports 60, 61, 63, 65.
In other cases coolant may pass over the sensor 19 first, then
bypass the sensor 19 on the way uphole. Coolant may be supplied
directly over components 30, or indirectly if passed adjacent
components 30 or over a component casing (not shown) for protecting
components 30 from contact with the coolant.
[0110] A characteristic of a well 26 may be monitored using sensor
19 (FIG. 1). Coolant may be supplied through one or more supply
lines 32, and returned through one or more return lines 34.
[0111] Referring to FIG. 5, the method may involve switching
between a first mode and a second mode. In the first mode coolant
is supplied through the one or more supply lines 32 and returned
through the one or more return lines 34 as described above. In the
second mode, coolant is supplied through the one or more supply
lines 32 and the one or more return lines 34 and returned up the
coiled tubing 40, for example up the coiled tubing annulus 44.
Modes may be switched by reconfiguring the tool, for example while
the tool is within or out of the well 26. In an example of
reconfiguration while the tool 94 is in the well 26, plates 78 may
have ports (not shown) that are open to the coiled tubing annulus
44, so that in the first mode some coolant pools in annulus 44,
while the bulk of coolant is returned up return line 34. Annulus 44
may be plugged at a suitable point, for example at a point above
ground, so that coolant preferentially flows up return lines 34.
However, if more coolant is needed to be supplied to the tool 94,
annulus 44 is unplugged and connected to a coolant return 52, and
return line 34 connected to supply coolant. Thus, the flux of
coolant to tool 94 may be increased. Other suitable techniques for
switching modes may be used.
[0112] Referring to FIG. 19, another example of switching modes is
illustrated. When in the first mode, coolant is supplied via supply
line 32 and returned via return line 34 through check valve 77 in
the uphole portion or end 64 of chamber 58. A check valve (not
shown) may be provided on ports 65 in plate 85 so that a pressure
in the chamber 58 lower than a coiled tubing annulus pressure, for
example when line 34 is sucking coolant uphole, will not lead to
appreciable coolant transfer through ports 65 into annulus 44. At
least a portion of annulus 44 may be pressurized to an extent
sufficient to prevent or reduce undesired filling with coolant
while in the first mode. To switch into the second mode, the
coolant flow through return line 34 is reversed for example above
ground, and coolant supplied through return line 34 across check
valve 75 through port 63 in the same fashion as provided by supply
line 32, with coolant then passing through ports 61 in plate 83
into chamber 58. Check valve 77 now prevents re-entry of coolant in
chamber 58 into return line 34, and coolant is returned up annulus
44 (or an additional return line (not shown) as provided. In some
of the embodiments disclosed herein the supply of coolant may be
through the annulus 44. The supply of coolant may also be into the
uphole portion 64 of chamber 58.
[0113] Referring to FIG. 12, an exploded view of the embodiment of
FIG. 3 is illustrated, with supply and return lines 32 and 34
omitted for clarity. FIGS. 13-18 illustrate cross-sections taken at
the marked points along the tool 94 of FIG. 12. Lines 103 drawn
perpendicular to the outer profile 106 of tool 94 in FIGS. 14-15,
and 17-18 illustrate exemplary axial placement points of threaded
holes 105. A transition component 108 is provided with a coiled
tubing connector 104 on one end and a seat 110 on the other end for
mounting plate 87 of uphole ported plate assembly 82 within seat
110. Ported plate assemblies 82 and 84 may have an inner tubular 91
for one or more wirelines (not shown). One or more sleeves 112, in
this case spacer sleeves 112A and 112B are provided for seating and
housing ported plate assemblies 82 and 84, respectively. Sleeves
112 may be added or subtracted as is required to ensure that
chamber 58 (FIG. 2) has the required length to house the applicable
sensor 19. A further sleeve 114 may be provided to seat the
downhole end 115 of ported plate assembly 84, and a bull nose cap
116 added to define secondary chamber 76. Components may be secured
together using screws, welding, and other suitable methods, and may
incorporate gaskets such as rubber or brass gaskets to ensure a
fluid tight seal. In some cases rubber should not be used, in
addition to other types of material that may melt in the downhole
environment.
[0114] The tool 94 may be used in downhole environments hotter than
ambient temperature, for example above a range of safe operating
temperatures of the sensor 19. Materials other than steel or metal
may be used to construct part or all of the apparatuses described
herein. For example, the sleeves 112 may be constructed of material
that allows the enclosed sensor 19 to operate properly.
[0115] Referring to FIGS. 20A-C, an embodiment of tool 94 is
illustrated with sensor 19 at least partially in fluid contact with
the exterior wellbore 120, for example in the case of a sonic
logging sensor 19A. Sensor 19 is housed at least partially within
tube 91, which has a hole 122 that allows sensor 19 to communicate
with wellbore 120 via a passage 124 defined by a radial sheath 126
extended to housing 54 (FIG. 20A). Thus, the housing may have a
port (passage 124) that allows coolant to at least partially
discharge into the wellbore. Sheath 126 may extend from an annular
saddle 127 surrounding tube 91. Sensor 19 may be cooled one or both
of indirectly by coolant passing through chamber 58 (FIG. 20A), or
directly via one or more supply lines 32A passing through tube 91
and into contact with sensor 19 (FIG. 20B). Coolant from line 32A
may exit tool 94 via window passage 124 into wellbore 120 (FIG.
20A), or may return up the tool 94 via one or more return lines
(not shown). A cover (not shown) may seal sensor 19 from wellbore
120, for example if the cover is transparent to signals transmitted
or received by sensor 19 for further example if the housing 54 is
not transparent to such signals.
[0116] Referring to FIGS. 21 and 22 and as mentioned above,
components of sensor 19 may be positioned at least partially
outside chamber 58, for example at least partially outside of
housing 54. For example, at least part of sensor 19 may include one
or more high temperature resistant components such as a caliper 130
(FIG. 21), or an antenna 134 (FIG. 22) such as a transmitter or
receiver antenna in a resistivity tool 136, that may be mounted for
example to housing 54.
[0117] Referring to FIG. 23, a video camera 138 may be also be
mounted on the tool 94, for example in or on the downhole end 140
of the tool, for further example set up to view laterally and/or
forwardly, and cooled by the cooling fluid either separately or
together with other sensors. The video camera may be located within
the chamber 58 or preferably within the secondary chamber 76, with
an opening 141 in the housing 54, or within the bull nose cap 116,
that may be provided with a transparent cover or lens 142. The
video camera may be placed to receive light from the opening either
directly or via a light guide 144 such as an optical fiber or
mirrors. The cover or lens is provided to allow the video camera to
transmit light to the wellbore or receive light from the wellbore,
but prevent fluids escaping from the cooling chamber. In other
embodiments, the opening 141 may not be covered so as to allow at
least a portion of the coolant to discharge through the opening
141. The camera may extend at least partially outside of the
opening 141, for example if at least part of camera 138 is located
in a transparent sheath (not shown) extending from opening 141. The
video camera may be provided with cables or other two way
communication means connecting the camera to surface for
instantaneous viewing and control and/or may have recording
capability. In all embodiments disclosed herein, various
communication means may be used such as wireless, fluid pulse and
sonic.
[0118] In some cases, the method and system may include one or more
temperature sensors, for example, provided within or part of sensor
56. The temperature sensor may be connected to control fluid flow
through the one or more coolant supply lines based on a temperature
sensed by the temperature sensor. For example, the temperature
sensor may be connected to send temperature signals to a controller
that in response sends signals to increase or decrease coolant flow
depending on the sensed temperature within the housing. The
temperature sensor may be in the form of a thermostat valve. A
thermostat or thermostat valve may open or throttle, automatically
or remotely, when the temperature at, in, or near the housing
reaches a predetermined temperature. The thermostatically
controlled valve may allow fluid to flow out the end of the tool
into the well, for example if the thermostat valve is located on
window passage 124. The one or more temperature sensors may monitor
temperature outside the housing as well, for example in real time.
This provides data to control the down hole temperature. If the
temperature starts to rise beyond a target temperature, the pump
rate and surface cooling rates may be increased, if the down hole
is below the target temperature the pump rate may be decreased.
This system also ensures the customer is getting value for their
investment and may be used to evaluate any down hole failures to
the tools the system is cooling.
[0119] In some embodiments, the downhole tool 94 may comprise a
production pump, for example instead of or in addition to the
sensor 56. One or more coolant supply and return lines 32 and 34
may extend to and from, respectively, the production pump. The pump
may be positioned at least partially within housing 54. The
production pump may be an electric submersible pump. The system may
be used throughout the life of a well to cool the production pump.
The housing or flask may cover all or a portion of the pump and the
cooling lines and the surface equipment may be permanently
installed. One surface installation (pumps, coolant reservoir,
cooling tower or heat exchangers) may feed coolant to multiple
pumps in multiple wells. The temperature monitoring system may
include surface display and recording instruments, down hole thermo
couples and a conductor or telemetry system used to communicate
between the down hole thermocouples and the surface equipment.
[0120] Referring to FIG. 24, another embodiment of a downhole tool
94 and method of use is illustrated. A downhole tool 94 includes a
housing 54 enclosing at least a part of a tool component, for
example sensor 56. Tool 94 also includes one or more coolant return
lines 34, in this case an annulus of the tool 94. At least a
portion of lines 34 extend to the housing 54, in order to receive
return coolant from housing 54 for example from housing return line
164. Tool 94 also includes one or more coolant supply lines 32.
Lines 32 include at least a first portion 160 and a second portion
162. The first portion 160, for example the remainder of the one
supply line shown downhole of point 163, is extended to the housing
54 to supply coolant to the housing. The second portion 162 is
extended, at a point 163 uphole of the housing 54, to the one or
more coolant return lines 34. Thus, a portion of coolant can be
supplied to the housing 54, while a portion can be diverted back up
the hole without passing through housing 54. The capacity of
coolant that can be supplied to the housing 54 (first portion) may
be limited by various factors such as the dimensions of the
interior of the housing, and the size of ports to the housing. As
the coolant travels downhole it may be heated by the formation. To
reduce the temperature increase of the first portion of fluid, the
second portion of coolant is sent downhole with the first portion
for example along direction lines 166 to absorb formation heat and
thermally shield the first portion. In the example shown, the use
of ports 162 allows a % of coolant, for example 90% to pass along
lines 170 through ports 162 back up the hole while only 5% enters
the housing 54 along direction line 168. The flux of fluid entering
the housing 54 is dictated by the number and size of ports 162 in
the example shown. In other cases the first portion and second
portion may be carried in respective fluid lines. One or more of
the ports 162 may be controlled for example selectively opened or
closed on the fly to adjust the proportion of total coolant flow
that is passing through ports 162.
[0121] In the claims, the word "comprising" is used in its
inclusive sense and does not exclude other elements being present.
The indefinite articles "a" and "an" before a claim feature do not
exclude more than one of the feature being present. Each one of the
individual features described here may be used in one or more
embodiments and is not, by virtue only of being described here, to
be construed as essential to all embodiments as defined by the
claims.
* * * * *