Shut-in tools and method

A method of efficient drawdown and buildup testing of a completed producing well, said well having therein a production tubing string through which well fluids are produced from a subsurface formation intersected by said well, said method comprising:

• (a) providing in said production tubing string an automatically controlled shut-in tool for controlling flow of well fluid up through said production tubing string, said shut-in tool having an open position and a closed position;
• said providing step including:
• (a) (1) running said shut-in tool down into said production tubing string;
• and
• (a) (2) setting said shut-in tool in place at a downhole location within said production tubing string and sealing said shut-in tool against an inner bore of said production tubing string at said downhole location so that fluid flow up through said production tubing string past said downhole location must flow through said shut-in tool;
• (b) shutting in said well by closing said shut-in tool;
• (c) monitoring a downhole parameter;
• (d) sensing when said downhole parameter has achieved a criteria;
• (e) generating a command signal in response to said sensing of step (d);
• and
• (f) automatically opening said shut-in tool in response to said command signal.

A method of efficient drawdown and buildup testing of a completed producing well, said well having therein a production tubing string through which well fluids are produced from a subsurface formation intersected by said well, said method comprising:

• (a) providing in said production tubing string an automatically controlled shut-in tool for controlling flow of well fluid up through said production tubing string, said shut-in tool having an open position and a closed position:
• (b) shutting in said well by closing said shut-in tool;
• (c) monitoring a downhole parameter;
• (d) sensing when said downhole parameter has achieved a criteria;
• (e) generating a command signal in response to said sensing of step (d);
• (f) automatically opening said shut-in tool in response to said command signal;
• (g) recording said downhole parameter in a memory contained in said automatically controlled shut-in tool;
• (h) retrieving said shut-in tool from said production tubing string;
• and
• (i) recovering recorded data on said downhole parameter from said memory of said shut-in tool.

A method of efficient drawdown and buildup testing of a completed producing well, said well having therein a production tubing string through which well fluids are produced from a subsurface formation intersected by said well, said method comprising:

• (a) providing in said production tubing string an automatically controlled shut-in tool for controlling flow of well fluid up through said production tubing string, said shut-in tool having an open position and a closed position:
• (b) shutting in said well by closing said shut-in tool;
• (c) monitoring a downhole parameter;
• (d) sensing when said downhole parameter has achieved a criteria;
• (e) generating a command signal in response to said sensing of step (d);
• (f) automatically opening said shut-in tool in response to said command signal;
• wherein steps (b) through (f) are at least a part of a first drawdown and buildup test of said well;
• and
• said method further comprises:
• after said first drawdown and buildup test, placing said well back in production while leaving said shut-in tool in place in said production tubing string;
• and
• subsequently repeating steps (b) through (f) to perform a second drawdown and buildup test with said shut-in tool, and thereby eliminating repeated trips of said shut-in tool into and out of said well.

A test string for conducting automatically controlled drawdown and buildup tests and for sampling well fluid, comprising:

• a shut-in tool, capable of repeatedly opening and closing, for controlling a flow of well fluid from said well;
• a sampling tool for trapping a sample of well fluid;
• monitoring means for monitoring a downhole parameter and generating input signals representative of said downhole parameter;
• and
• controller means for controlling said shut-in tool to run a drawdown and buildup test, and for automatically operating said sampling tool to trap said sample of well fluid at a predetermined stage of said drawdown and buildup test, said controller means including:
• processor means, having programmed criteria stored therein, for receiving said input signals and for generating shut-in command signals and a sampling command signal when said input signals meet corresponding portion of said programmed criteria;
• shut-in tool control means for moving said shut-in tool between open and closed positions thereof in response to said shut-in command signals;
• and
• sampling tool control means for operating said sampling tool to trap said sample of well fluid therein in response to said sampling command signal.

A test string for conducting automatically controlled drawdown and buildup tests and for sampling well fluid, comprising:

• a shut-in tool, capable of repeatedly opening and closing, for controlling a flow of well fluid from said well;
• a sampling tool for trapping a sample of well fluid;
• monitoring means for monitoring a downhole parameter and generating input signals representative of said downhole parameter;
• and
• controller means for controlling said shut-in tool to run a drawdown and buildup test, and for automatically operating said sampling tool to trap said sample of well fluid at a predetermined stage of said drawdown and buildup test, said controller means including:
• means for generating a shut-in command signal when a value of a current said input signal is within a first predetermined range of a value of a prior said input signal;
• means for generating a sampling command signal when a value of a current said input signal is within a second predetermined range of a value of a prior said input signal;
• shut-in tool control means for moving said shut-in tool between open and closed positions thereof in response to said shut-in command signal;
• and
• sampling tool control means for operating said sampling tool to trap said sample of well fluid therein in response to said sampling command signal.

A test string for conducting automatically controlled drawdown and buildup tests and for sampling well fluid, comprising:

• a shut-in tool, capable of repeatedly opening and closing, for controlling a flow of well fluid from said well;
• a sampling tool for trapping a sample of well fluid;
• monitoring means for monitoring a downhole parameter and generating input signals representative of said downhole parameter;
• and
• controller means for controlling said shut-in tool to run a drawdown and buildup test, and for automatically operating said sampling tool to trap said sample of well fluid at a predetermined stage of said drawdown and buildup test, said controller means including:
• means for generating a shut-in command signal when a value of a current said input signal is within a predetermined range of a value of a prior said input signal;
• means for generating a sampling command signal during a time period when a value of a current said input signal is within said predetermined range of a value of a prior said input signal;
• shut-in tool control means for moving said shut-in tool between open and closed positions thereof in response to said shut-in command signal;
• and
• sampling tool control means for operating said sampling tool to trap said sample of well fluid therein in response to said sampling command signal.

A test string for conducting automatically controlled drawdown and buildup tests and for sampling well fluid, said test string being adapted for testing of a completed producing well, said well having a production tubing string therein, comprising:

• a shut-in tool, capable of repeatedly opening and closing, for controlling a flow of well fluid from said well;
• a sampling tool for trapping a sample of well fluid;
• monitoring means for monitoring a downhole parameter and generating input signals representative of said downhole parameter;
• controller means for controlling said shut-in tool to run a drawdown and buildup test, and for automatically operating said sampling tool to trap said sample of well fluid at a predetermined stage of said drawdown and buildup test;
• and
• setting means for setting said shut-in tool in place at a downhole location within said production tubing string and sealing against an inner bore of said production tubing string at said downhole location so that well fluid flow up through said production tubing string must flow through said shut-in tool.

A method of automatically controlled sampling of well fluid from a well during drawdown and buildup testing, comprising:

• (a) shutting in and then opening said well to perform a drawdown and buildup test on said well;
• (b) monitoring a downhole parameter during said drawdown and buildup test;
• and
• (c) trapping a well fluid sample automatically in response to said monitored downhole parameter.

A method of efficient drawdown and buildup testing of a well having therein a tubing string through which well fluids flow from a subsurface formation intersected by said well, said method comprising:

• (a) providing in said tubing string an automatically controlled shut-in tool for controlling flow of well fluid up through said tubing string, said shut-in tool having an open position and a closed position;
• (b) shutting in said well by closing said shut-in tool;
• (c) monitoring a downhole parameter;
• (d) sensing when said downhole parameter has reached a stabilized level at which there is no further significant change in said parameter;
• (e) generating a command signal in response to said sensing of step (d);
• (f) automatically opening said shut-in tool in response to said command signal;
• (g) recording said downhole parameter in a memory contained in said automatically controlled shut-in tool;
• (h) retrieving said shut-in tool from said well;
• and
• (i) recovering recorded data on said downhole parameter from said memory of said shut-in tool.