Communicating commands to a well tool

Details Communicating commands to a well tool Communicating commands to a well tool

2000-11-14

2003-03-25

Bagnell, David (Department: 3673)

Wells

Processes

Operating valve, closure, or changeable restrictor in a well

C166S363000

Reexamination Certificate

active

06536529

ABSTRACT:

BACKGROUND
The invention generally relates to communicating commands to a well tool.
Referring to
FIG. 1
, for purposes of measuring characteristics (e.g., formation pressure) of a subterranean formation
31
, a tubular string
10
may be inserted into a wellbore which extends into the formation
31
. In order to test a particular region, or zone
33
, of the formation
31
, the string
10
may include a perforating gun
30
that is used to penetrate a well casing
12
and form fractures
29
in the formation
31
. To seal off the zone
33
from the surface of the well, the string
10
typically includes a packer
26
that forms a seal between the exterior of the string
10
and the internal surface of the well casing
12
. Below the packer
26
, a recorder
11
of the string
10
takes measurements of the formation
31
.
The tool
21
typically has valves to control the flow of fluid into and out of a central passageway of the string
10
. An in-line ball valve
22
is used to control the flow of well fluid from the formation
31
up through the central passageway of the test string
10
. Above the packer
26
, a circulation valve
20
is used to control fluid communication between an annulus
16
surrounding the string
10
and the central passageway of the string
10
.
The ball valve
22
and the circulation valve
20
can be controlled by commands (e.g., “open valve” or “close valve”) that are sent downhole. Each command is encoded into a predetermnined signature of pressure pulses
34
(
FIG. 2
) transmitted downhole to the tool
21
via hydrostatic fluid present in the annulus
16
. A sensor
25
of the tool
21
receives the pressure pulses
34
, and the command is extracted. Electronics and hydraulics of the string
10
then operate the valves
20
and
22
to execute the command.
For purposes of generating the pressure pulses
34
, a port
18
in the casing
12
extends to a manually operated pump (not shown). The pump is selectively turned on and off by an operator to encode the command into the pressure pulses
34
. A duration T
0
(e.g., 1 min.) of the pulse
34
, a pressure P
0
(e.g., 250 p.s.i.) of the pulse
34
, and the number of pulses
34
in succession form the signature that uniquely identifies the command.
FIG. 1
depicts a land-based well. However, similar pressure pulses may be used to communicate commands to a well tool that is disposed in a subsea well. For example, a subsea well may have a Blowout Preventor (BOP) that is located just above surface of the sea floor and is connected, at its lower end to a wellhead of the well and to the surface vessel by a pressure containing conduit known as a marine riser. The BOP stack forms a sealed entry point to the well as well as other devices, such as a tubing hanger (for example), a mechanism that, as its name implies, holds the top end of production tubing that extends down into the well bore. For purposes of installing the tubing hanger inside the well, a tool called a tubing hanger running tool (THRT) may be used, and this tool may be actuated via pressure pulses.
More specifically, the tubing hanger running tool may be tethered to a floating platform at the surface of the well. In this manner, a tubing called a landing string may be connected between the surface floating vessel/rig/platform and the THRT within a marine riser, onto which an umbilical containing hydraulic and electrical conduits may be clamped externally for the purpose of communication with the THRT. The long umbilical that is used to communicate commands to the tubing hanger running tool may be significantly expensive and may significantly increase the time needed to deploy and retrieve the tool.
Thus, there is a continuing need for an arrangement that addresses one or more of the problems that are stated above.
SUMMARY
In an embodiment of the invention, a system for use with a subsea well that includes a BOP includes a fluid line and a tool that is not connected to the fluid line. The fluid line is connected to the BOP to communicate a pressure encoding a command, and the tool is adapted to decode and respond to the command when the tool is inside the BOP.


REFERENCES:
patent: 4212355 (1980-07-01), Reardon
patent: 4896722 (1990-01-01), Upchurch
patent: 4915168 (1990-04-01), Upchurch
patent: 4953618 (1990-09-01), Hamid et al.
patent: 5044442 (1991-09-01), Nobileau
patent: 5515336 (1996-05-01), Chin et al.
patent: 5963138 (1999-10-01), Gruenhagen
patent: 5971077 (1999-10-01), Lilley
patent: 6182764 (2001-02-01), Vaynshteyn
patent: 6293344 (2001-09-01), Nixon et al.
patent: 6321846 (2001-11-01), Rytlewski
patent: 0 344 060 (1989-11-01), None
patent: 0 604 134 (1994-06-01), None

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