US3673864A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods and apparatus for detecting the entry of formation gases into a well bore
Assignee: Schlumberger Technology Corp
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Filing: 1970-12-14
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Granted: 1972-07-04
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Expires: 1990-12-14
Abstract
Abstract As a preferred mode for practicing the invention disclosed herein, drilling mud in a borehole is fluidly communicated with an enclosed testing chamber by means of a gas-pervious liquid barrier which is at a reduced pressure so that, should there be higher-pressure formation gases dissolved or entrained in the drilling mud, the gases will be drawn through the barrier into the testing chamber. In this manner, by monitoring either the pressure or temperature within the testing chamber, the presence or absence of formation gases in the drilling mud can be ascertained; and, if desired, these measurements can be employed to at least estimate the percentage of gases in the mud sample. In the representative embodiment of the apparatus of the present invention disclosed herein, a tool arranged for coupling into a drill string is provided with a mud-sampling passage which is fluidly coupled to an enclosed testing chamber by a liquid barrier formed of a gas-pervious material. One or more measuring devices, such as pressure and temperature monitors, are arranged in the testing chamber for detecting the admission of gas into the chamber.
Inventors
- 👤 Walter E Cubberly Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:08
CPC Classifications
E; E21; E21B; E21B49/00; E21B49/08; E21B21/00; E21B21/06; E21B21/063; E21B21/067; E21B21/08; E21B47/00; E21B47/06; E21B49/005
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
146 words
A method for determining whether pressured formation gases are present in the drilling mud in a borehole which is being excavated by a drill bit and comprising the steps of: positioning an enclosed testing chamber which is at a pressure less than that of formation gases which may be present in said drilling mud at a selected depth in said borehole adjacent to said drill bit; communicating said drilling mud with said testing chamber by means of a gas-pervious liquid barrier for separating formation gases from said drilling mud and drawing such separated formation gases into said testing chamber; and monitoring a condition in said testing chamber that is indicative of the entrance of said separated formation gases into said testing chamber for providing a signal at the earth''s surface which is characteristic of the presence or absence of said formation gases in said drilling mud.
Claim 2
Independent Claim
146 words
A method for determining whether pressured formation gases are present in the drilling mud in a borehole which is being excavated by a drill bit and comprising the steps of: positioning an enclosed testing chamber which is at a pressure less than that of formation gases which may be present in said drilling mud at a selected depth in said borehole adjacent to said drill bit; communicating said drilling mud with said testing chamber by means of a gas-pervious liquid barrier for separating formation gases from said drilling mud and drawing such separated formation gases into said testing chamber; and monitoring a condition in said testing chamber that is indicative of the entrance of said separated formation gases into said testing chamber for providing a signal at the earth''s surface which is characteristic of the presence or absence of said formation gases in said drilling mud.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein said monitored condition is the pressure of gases in said testing chamber.
Claim 4
Dependent Claim
18 words
The method of claim 1 wherein said monitored condition is the temperature of gases in said testing chamber.
Claim 5
Independent Claim
190 words
A method for determining whether pressured formation gases are present in the drilling mud in a borehole which is being excavated by a drilL bit coupled to a drill string and comprising the steps of: coupling an enclosed testing chamber which is at a reduced pressure to said drill string for positioning said testing chamber at a selected depth in said borehole as said drill bit is excavating said borehole; communicating said drilling mud with said testing chamber by means of a gas-pervious liquid barrier for separating a sample of formation gases from said drilling mud and drawing said gas sample into said testing chamber; monitoring at least one condition in said testing chamber that is characteristic of the entrance of said gas sample into said testing chamber for producing a first signal indicative of the presence or absence of a gas sample in said testing chamber; and, in response to said first signal, producing a second signal that is detectable at the surface of the earth for providing surface indications which are characteristic of the presence or absence of formation gases in said drilling mud at said selected depth.
Claim 6
Independent Claim
190 words
A method for determining whether pressured formation gases are present in the drilling mud in a borehole which is being excavated by a drilL bit coupled to a drill string and comprising the steps of: coupling an enclosed testing chamber which is at a reduced pressure to said drill string for positioning said testing chamber at a selected depth in said borehole as said drill bit is excavating said borehole; communicating said drilling mud with said testing chamber by means of a gas-pervious liquid barrier for separating a sample of formation gases from said drilling mud and drawing said gas sample into said testing chamber; monitoring at least one condition in said testing chamber that is characteristic of the entrance of said gas sample into said testing chamber for producing a first signal indicative of the presence or absence of a gas sample in said testing chamber; and, in response to said first signal, producing a second signal that is detectable at the surface of the earth for providing surface indications which are characteristic of the presence or absence of formation gases in said drilling mud at said selected depth.
Claim 7
Dependent Claim
23 words
The method of claim 4 wherein said monitored condition varies in accordance with the quantity of said gas sample entering said testing chamber.
Claim 8
Dependent Claim
20 words
The method of claim 4 wherein said monitored condition is the pressure of said gas sample in said testing chamber.
Claim 9
Dependent Claim
20 words
The method of claim 4 wherein said monitored condition is the temperature of said gas sample in said testing chamber.
Claim 10
Dependent Claim
150 words
The method of claim 4 further including the steps of: once said second signal is produced, discharging said gas sample from said testing chamber for returning said testing chamber to a reduced pressure less than that of pressured formation gases in said drilling mud at said selected depth; recommunicating said drilling mud with said testing chamber by means of said liquid barrier for separating a second sample of formation gases from said drilling mud and drawing said second gas sample into said testing chamber; remonitoring said one condition for producing a third signal indicative of the presence or absence of a gas sample in said testing chamber; and, in response to said third signal, producing a fourth signal that is detectable at the surface of the earth for providing surface indications which are characteristic of the presence or absence of formation gases in said drilling mud at said selected depth.
Claim 11
Independent Claim
210 words
A method for determining whether pressured formation gases are present in the drilling mud in a borehole which is being excavated by a drill bit coupled to a drill string and comprising the steps of: coupling an enclosed testing chamber and an enclosed receiving chamber which are respectively at a reduced pressure to said drill string for positioning said chambers at a selected depth in said borehole as said drill bit is excavating said borehole; communicating said drilling mud with said testing chamber by means of a gas-pervious liquid barrier for separating a sample of formation gases from said drilling mud and drawing said gas sample into said testing chamber; monitoring the pressure in said testing chamber for producing a first signal indicative of whether a gas sample entered said testing chamber; producing a second signal in response to said first signal for providing an indication at the surface which is characteristic of the presence or absence of formation gases in said drilling mud at said selected depth; and, upon receiving said second signal indicating that formation gases are present in said drilling mud at said selected depth, communicating said testing chamber with said receiving chamber to lower the pressure in said testing chamber for introduction of another gas sample.
Claim 12
Independent Claim
210 words
A method for determining whether pressured formation gases are present in the drilling mud in a borehole which is being excavated by a drill bit coupled to a drill string and comprising the steps of: coupling an enclosed testing chamber and an enclosed receiving chamber which are respectively at a reduced pressure to said drill string for positioning said chambers at a selected depth in said borehole as said drill bit is excavating said borehole; communicating said drilling mud with said testing chamber by means of a gas-pervious liquid barrier for separating a sample of formation gases from said drilling mud and drawing said gas sample into said testing chamber; monitoring the pressure in said testing chamber for producing a first signal indicative of whether a gas sample entered said testing chamber; producing a second signal in response to said first signal for providing an indication at the surface which is characteristic of the presence or absence of formation gases in said drilling mud at said selected depth; and, upon receiving said second signal indicating that formation gases are present in said drilling mud at said selected depth, communicating said testing chamber with said receiving chamber to lower the pressure in said testing chamber for introduction of another gas sample.
Claim 13
Dependent Claim
62 words
The method of claim 9 further including the steps of: monitoring the pressure in said receiving chamber for producing a third signal indicative of whether said gas sample entered said receiving chamber; and producing a fourth signal in response to said third signal for providing an indication at the surface which is characteristic of whether said gas sample entered said receiving chamber.
Claim 14
Dependent Claim
69 words
The Method of claim 9 further including the steps of: monitoring the temperature in said testing chamber for producing a third signal indicative of whether a gas sample entered said testing chamber; and producing a fourth signal in response to said third signal for providing an indication at the surface which is characteristic of the presence or absence of formation gases in said drilling mud at said selected depth.
Claim 15
Dependent Claim
53 words
The method of claim 11 wherein said signals are obtained before and after a gas sample has entered said testing chamber and further including the step of: correlating said second and fourth signals in accordance with the General Gas Law for determining the gas content of said drilling mud at said selected depth.
Claim 16
Dependent Claim
166 words
Apparatus for determining whether pressured formation gases are present in the drilling mud in a borehole which is being excavated and comprising: a drill string having a drill bit coupled thereto; means on said drill string defining an enclosed testing chamber which is adapted to initially be at a reduced pressure; a mud passage between said testing chamber and the exterior thereof; means defining a gas-pervious liquid barrier between said mud passage and said testing chamber and adapted for passing only formation gases in drilling mud within said mud passage into said testing chamber; condition-monitoring means in said testing chamber adapted to provide first signals indicative of the passage of a formation gas sample through said gas-pervious liquid barrier into said testing chamber; and signaling means on said drill string and operable in response to said first signals for producing second signals at the surface of the earth which are indicative of the presence or absence of formation gases in drilling mud within said mud passage.
Claim 17
Dependent Claim
166 words
Apparatus for determining whether pressured formation gases are present in the drilling mud in a borehole which is being excavated and comprising: a drill string having a drill bit coupled thereto; means on said drill string defining an enclosed testing chamber which is adapted to initially be at a reduced pressure; a mud passage between said testing chamber and the exterior thereof; means defining a gas-pervious liquid barrier between said mud passage and said testing chamber and adapted for passing only formation gases in drilling mud within said mud passage into said testing chamber; condition-monitoring means in said testing chamber adapted to provide first signals indicative of the passage of a formation gas sample through said gas-pervious liquid barrier into said testing chamber; and signaling means on said drill string and operable in response to said first signals for producing second signals at the surface of the earth which are indicative of the presence or absence of formation gases in drilling mud within said mud passage.
Claim 18
Dependent Claim
29 words
The apparatus of claim 13 wherein said condition-monitoring means include a pressure transducer adapted for providing said first signals which are representative of the pressure in said testing chamber.
Claim 19
Dependent Claim
29 words
The apparatus of claim 13 wherein said condition-monitoring means include a temperature transducer adapted for providing said first signals which are representative of the temperature in said testing chamber.
Claim 20
Dependent Claim
35 words
The apparatus of claim 13 wherein said gas-pervious liquid barrier is comprised of a member of a gas-pervious, liquid-impermeable material sealingly arranged in said mud passage and separating said mud passage from said testing chamber.
Claim 21
Dependent Claim
16 words
The apparatus of claim 16 wherein said barrier member is substantially formed of an elastomeric material.
Claim 22
Dependent Claim
95 words
The apparatus of claim 13 wherein said signaling means include: means on said drill string adapted for momentarily interrupting the flow of drilling mud through said drill string to produce pressure variations which are transmitted therethrough to the surface; means on said drill string coupling said flow-interrupting means and said condition-monitoring means and adapted for actuating said flow-interrupting means in response to said first signals to produce said second signals; and means at the surface responsive to the arrival of said second signals at the surface for providing characteristic indications representative of said first signals.
Claim 23
Dependent Claim
68 words
The apparatus of claim 13 further including: means on said drill string defining an enclosed receiving chamber which is adapted to initially be at a reduced pressure; passage means communicating said testing chamber with said receiving chamber; and valve means in said passage means normally blocking communication between said chambers and adapted to be opened for discharging a gas sample in said testing chamber into said receiving chamber.
Claim 24
Dependent Claim
43 words
The apparatus of claim 19 wherein said valve means include actuating means adapted for opening said valve means only in response to an increase of gas pressure in said testing chamber to a predetermined level above the gas pressure in said receiving chamber.
Claim 25
Dependent Claim
77 words
The apparatus of claim 19 further including: second condition-monitoring meaNs in said receiving chamber adapted to provide third signals indicative of the discharge of a formation gas sample from said testing chamber into said receiving chamber; and means coupling said second condition monitoring means to said signaling means for producing fourth signals at the surface of the earth which are indicative of the discharge of a formation gas sample from said testing chamber into said receiving chamber.
Claim 26
Dependent Claim
155 words
Apparatus adapted for determining whether pressured formation gases are present in the drilling mud in a borehole which is being excavated and comprising: a body adapted for coupling in a drill string and including a passage therethrough for conducting drilling mud from such a drill string to a drill bit coupled thereto below said body; an enclosed testing chamber arranged in said body and adapted to initially be at a reduced pressure; a mud passage in said body communicating said testing chamber with the exterior of said body; a gas-pervious liquid-impermeable barrier sealingly fitted to said body and adapted for blocking the flow of drilling mud into said testing chamber and passing formation gases into said testing chamber when such gases are at a higher pressure than that of said testing chamber; and a condition-monitoring transducer in said testing chamber and adapted for producing electrical signals representative of a selected condition in said testing chamber.
Claim 27
Dependent Claim
155 words
Apparatus adapted for determining whether pressured formation gases are present in the drilling mud in a borehole which is being excavated and comprising: a body adapted for coupling in a drill string and including a passage therethrough for conducting drilling mud from such a drill string to a drill bit coupled thereto below said body; an enclosed testing chamber arranged in said body and adapted to initially be at a reduced pressure; a mud passage in said body communicating said testing chamber with the exterior of said body; a gas-pervious liquid-impermeable barrier sealingly fitted to said body and adapted for blocking the flow of drilling mud into said testing chamber and passing formation gases into said testing chamber when such gases are at a higher pressure than that of said testing chamber; and a condition-monitoring transducer in said testing chamber and adapted for producing electrical signals representative of a selected condition in said testing chamber.
Claim 28
Dependent Claim
24 words
The apparatus of claim 22 wherein said transducer is adapted for producing electrical signals representative of the pressure of gases in said testing chamber.
Claim 29
Dependent Claim
24 words
The apparatus of claim 22 wherein said transducer is adapted for producing electrical signals representative of the temperature of gases in said testing chamber.
Claim 30
Dependent Claim
73 words
The apparatus of claim 22 further including: an enclosed receiving chamber arranged in said body and adapted to initially be at a reduced pressure; a gas passage in said body communicating said testing chamber with said receiving chamber; and valve means in said body normally closing said gas passage and adapted for opening only when the gas pressure in said testing chamber is at a level greater than that in said receiving chamber.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-04 | 1976-01-03 | 1976-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-04 | 1980-01-03 | 1980-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-04 | 1984-01-03 | 1984-07-04 | $7700.00 | Window Closed / Lapsed |