GB2275342A - Apparatus and method for measuring the sticking tendency of drilling mud. - Google Patents
Apparatus and method for measuring the sticking tendency of drilling mud. Download PDFInfo
- Publication number
- GB2275342A GB2275342A GB9303321A GB9303321A GB2275342A GB 2275342 A GB2275342 A GB 2275342A GB 9303321 A GB9303321 A GB 9303321A GB 9303321 A GB9303321 A GB 9303321A GB 2275342 A GB2275342 A GB 2275342A
- Authority
- GB
- United Kingdom
- Prior art keywords
- mud
- sensing body
- porous surface
- spherical
- measuring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000005553 drilling Methods 0.000 title claims abstract description 17
- 238000000034 method Methods 0.000 title claims description 12
- 239000000706 filtrate Substances 0.000 claims description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract description 8
- 238000005259 measurement Methods 0.000 abstract description 5
- 229910052757 nitrogen Inorganic materials 0.000 abstract description 4
- 230000015572 biosynthetic process Effects 0.000 description 12
- 238000005755 formation reaction Methods 0.000 description 12
- 239000012530 fluid Substances 0.000 description 7
- 239000007787 solid Substances 0.000 description 7
- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 5
- 235000010948 carboxy methyl cellulose Nutrition 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- 239000007789 gas Substances 0.000 description 3
- TZCXTZWJZNENPQ-UHFFFAOYSA-L barium sulfate Chemical compound [Ba+2].[O-]S([O-])(=O)=O TZCXTZWJZNENPQ-UHFFFAOYSA-L 0.000 description 2
- 239000010428 baryte Substances 0.000 description 2
- 229910052601 baryte Inorganic materials 0.000 description 2
- 239000000440 bentonite Substances 0.000 description 2
- 229910000278 bentonite Inorganic materials 0.000 description 2
- SVPXDRXYRYOSEX-UHFFFAOYSA-N bentoquatam Chemical compound O.O=[Si]=O.O=[Al]O[Al]=O SVPXDRXYRYOSEX-UHFFFAOYSA-N 0.000 description 2
- 239000012065 filter cake Substances 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 239000001768 carboxy methyl cellulose Substances 0.000 description 1
- 239000008112 carboxymethyl-cellulose Substances 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000839 emulsion Substances 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 230000004941 influx Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 208000024891 symptom Diseases 0.000 description 1
- 210000001550 testis Anatomy 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N11/00—Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties
- G01N11/10—Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties by moving a body within the material
- G01N11/14—Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties by moving a body within the material by using rotary bodies, e.g. vane
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/26—Oils; Viscous liquids; Paints; Inks
- G01N33/28—Oils, i.e. hydrocarbon liquids
- G01N33/2823—Raw oil, drilling fluid or polyphasic mixtures
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/24—Earth materials
- G01N33/241—Earth materials for hydrocarbon content
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Immunology (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Physics & Mathematics (AREA)
- Pathology (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Food Science & Technology (AREA)
- Medicinal Chemistry (AREA)
- Sampling And Sample Adjustment (AREA)
Abstract
A device for measuring the sticking tendency of drilling mud M comprising: a container 10 for the mud; a porous surface 16, 18 in the container and contacted on one side by the mud; a sensing body a spherical or part-spherical surface 30 within the container and adiacent the porous surface; means 32 for rotating the sensing body; means in the drive 32 for measuring resistance to rotation of the sensing body; and means for forcing the mud through the porous surface so as to build a mud cake thereon and around the sensing body, characterised in that the spherical or part-spherical surface 30 has a radius of curvature of less than about 4 inches. This arrangement allows repeated measurements on a single sample of mud. The forcing means is a supply of pressurised nitrogen which enters the cell 10 via a line 38. <IMAGE>
Description
APPARATUS AND METHOD FOR MEASURING THE STICKING
TENDENCY OF DRILLING MUD
The present invention relates to an apparatus by which the sticking tendency of a drilling mud can be measured and a method of measuring such tendencies.
In the drilling of boreholes such as oil or gas wells, a drilling fluid (hereinafter referred to as "drilling mud") is circulated through the well during drilling in order to, inter alia, remove drilled cuttings, balance the pressure of formation fluids to prevent influxes and maintain the stability of the borehole. In order to provide the required density and viscosity, the mud can include certain solids such as barite and bentonite as well as solids derived from the drilling action. When drilling oil and gas wells, it is quite common to encounter subterranean formations which are porous. If the hydrostatic pressure of the drilling fluid is greater than the pressure of fluids in such formations, mud will penetrate the formation.Generally the pore size of such formations is sufficient to admit the liquid components and very fine solids but to filter out the other solids such as barite or bentonite. These filtered solids form on the borehole wall as a filter cake known as "mud cake". Mud cake can be useful as it acts as a barrier to prevent fluid loss from the drilling mud to the formation. However if the mud cake becomes too thick, problems can occur.
The particular problem to which the present invention relates is that of differential sticking. Differential sticking occurs when a drill pipe, casing or logging tool becomes embedded in a mud cake and insufficient torque or overpull is available to free the pipe from the mud cake. Such sticking does not occur when the pipe is moving as the contact surface between the pipe and the mud cake are lubricated sufficiently such that the hookload or torque do not show the symptoms of sticking.
However, when movement is ceased the sticking effect becomes apparent over a relatively short period of time, often in the time required to add or remove a stand of pipe when running-in or tripping.
Differential sticking is particularly prevalent when drilling through porous formations while there is loss of fluid (filtrates) from the drilling mud to the formation and the presence of a significant mud cake. It is believed that most of the differential sticking is due to the interaction between the drill pipe, bottom hole assembly, tool, etc and the densest part of the mud cake which is close to the formation. Since it is essentially the nature of the mud which determines the fluid loss and mud cake growth from a given formation, it is proposed to determine the tendency of a mud to produce a situation likely to cause differential sticking when encountering porous formations.
It has been proposed to determine the sticking tendency of drilling mud using a device which comprises a cell having a filter at one end thereof, a sample of mud being placed in the cell and filtered so a to grow a mud cake to contact a plate adjacent the filter. Once the cake has grown up to the plate surface, the torque required to rotate the plate is measured to be used as a measure of the sticking tendency of the mud. The surface of the plate facing the filter is either flat or partspherical having a radius of curvature of about 12-" (equivalent to a 25" sphere).
The inventors have now found that it is desirable to be able to make a series of measurements of torque over time to obtain an accurate indication of the sticking tendency of the mud but that this is not possible with the previous design.
It is an object of the present invention to provide an apparatus and method which can be used to determine the sticking tendency of a mud which can be used to make repeated measurements on a single mud sample.
In accordance with a first aspect of the present invention, there is provided a device for measuring the sticking tendency of drilling mud comprising: a container for the mud; a porous surface in the container and contacted on one side by the mud; a sensing body comprising a spherical or part-spherical surface within the container and adjacent the porous surface; means for rotating the sensing body; means for measuring resistance to rotation of the sensing body; and means for forcing the mud filtrate through the porous surface so as to build a mud cake thereon and around the sensing body, characterised in that the spherical or part-spherical surface of the sensing body has a radius of curvature not more than about 4".
In accordance with a second aspect of the invention, there is provided a method for measuring the sticking tendency of a drilling mud comprising: providing a sensing body comprising a spherical or part-spherical surface adjacent a porous surface; surrounding the sensing body with the mud; forcing the mud filtrate through the porous surface so as to form a mud cake thereon around the sensing body; rotating the sensing body; and measuring the resistance to rotation of the body, characterised in that the resistance to rotation is measured at different times for a single sample of mud.
It is preferred that the sensing body comprises a ball which is conveniently rotated about an axis normal to the porous surface. In such a case the torque required to rotate the ball can be measured to obtain an indication of the resistance to movement. Preferably the ball has a diameter of less than 2", more preferably in the region of 1.5".
The porous surface typically comprises a drained filter such as the filter in a fluid loss filter process. The mud can be urged through the porous surface by gas pressure in which case the container is typically pressurised with nitrogen.
The present invention will now be described by way of example, with reference to the accompanying drawings which show one embodiment of a device according to a first aspect of the invention.
Referring now to the drawings, the device comprises an API-specified HPHT half-area filter press modified to embody the present invention. The press comprises a cell 10 having removable end portions 12, 14. The bottom end portion 12 is provided with a filter grid 18 and filter paper 16 which face the interior of the cell 10. A drain 20 is provided through the end portion 12 such that any filtrate passing through the paper 16 can be collected. The upper end portion 14 is provided with a bore 22 through which a shaft 24 passes by means of a low friction seal 26, 28. The portion of the shaft 24 projecting into the cell 10 has a stainless steel ball 30 mounted at the lower end thereof. The portion of the shaft 24 outside the cell 10 is connected to a drive unit 32 which incorporates a torque sensor (not shown), the unit 32 being supported above the cell 10 by means of a frame 34.The upper end portion 14 is also provided with a bore 36 which connected the interior of the cell 10 to a supply of pressurised nitrogen via a pipe 38.
In use, the bottom end portion 12 of the cell 10 is assembled with a clean filter paper 16. The cell is filled with a mud M to be testes The ball 30 is lowered into the mud M so as to rest on the filter paper 18 and the upper end portion 14 is sealed onto the cell 10. The mud M is pressurised with nitrogen from the pipe 38 to obtain a pressure differential to simulate the pressure differential between mud and pore fluid in the formation. As the filter cake grows, the torque required to initiate rotation of the ball 30 is measured by the torque sensor.
It can be shown that the torque Mo required to initiate rotation of the ball can be related to the time t for which the differential pressure has been applied according to the expression M0 = tt and the porosity of the mud to cause sticking s obtained by
s has been found to be strongly influenced by solids loading of the mud.
The results obtained with a device as shown in the drawing having a 12" diameter ball, a 200 PSI differential pressure and a 20% by volume solids loading are summarised in the table below:
Mud Stickance s Fluid loss /mNm min-3/4 1 /mL (30 min)-l WBM WBM 25 8 WBM+CMC WBM+CMC 10 3.2 WBM+MSF WBM+MSF 6.3 2.7 WBM+CMC+MSF 2.5 1.4 OBM 50/50 oil/water 1 3.5 0.5 In the table:
WBM = Water base mud
OBM = Oil base mud; invert emulsion
CMC = Carboxymethyl cellulose
MSF = Mixed surfactant fluid
The lower the value of s the lower the risk of differential sticking is assumed to
be.
Since the device described above is based on API fluid loss test, the API fluid
loss value can be easily derived from fluid loss measurements made during the
sticking test. Thus the test could be performed as frequently as fluid loss tests with
minimal extra effort A typical procedure might be as follows:
1 Collect mud sample
2 Assemble stickingffluid loss cell
3 Equilibrate to temperature and pressure as required
4 Apply differential pressure
5 Wait 30 minutes
6 Measure torque required to initiate rotation of ball
7 Record filtrate volume and convert to API fluid loss allowing for differences in
geometry and differential pressure.
If required, the torque measurement can be made continuously over the 30 minute period.
Claims (12)
1 A device for measuring the sticking tendency of drilling mud comprising: a
container for the mud; a porous surface in the container and contacted on one
side by the mud; a sensing body a spherical or part-spherical surface within the
container and adjacent the porous surface; means for rotating the sensing body;
means for measuring resistance to rotation of the sensing body; and means for
forcing the mud through the porous surface so as to build a mud cake thereon
and around the sensing body, characterised in that the spherical or part-spherical
surface has a radius of curvature of less than about 4 inches.
2 A device as claimed in claimed 1, wherein the spherical or part-spherical surface
has a radius of curvature of less than about 2 inches.
3 A device as claimed in claim 1 or 2, wherein the sensing body comprises a ball.
4 A device as claimed in claim 3, wherein the ball is rotated about an axis normal
to the porous surface.
5 A device as claimed in claim 4, wherein the torque required to rotate the ball is
measured to obtain an indication of the resistance to movement.
6 A device as claimed in any preceding claim, wherein the porous surface
comprises a filter.
7 A device as claimed in any preceding claim, wherein the mud filtrate is urged
through the porous surface by gas pressure.
8 A method for measuring the sticking tendency of a drill mud comprising:
providing a sensing body comprising a spherical or part-spherical surface
adjacent a porous surface; surrounding the sensing body with the mud; forcing
the mud filtrate through the porous surface so as to form a mud cake thereon
around the sensing body; rotating the sensing body; and measuring the
resistance to rotation of the body, characterised in that the resistance to rotation
is measured at different times for a single sample of mud.
9 A method as claimed in claim 8, wherein the sensing body comprises a ball.
10 A method as claimed in claim 9, wherein moving the sensing body comprises
rotating the ball about an axis normal to the porous surface.
11 A method as claimed in claim 10, wherein the torque required to rotate the ball
is measured to obtain an indication of the resistance to movement.
12 A method as claimed in claims 8 - 11, wherein the mud filtrate is urged through
the porous surface by gas pressure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9303321A GB2275342B (en) | 1993-02-19 | 1993-02-19 | Apparatus and method for measuring the sticking tendency of drilling mud |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9303321A GB2275342B (en) | 1993-02-19 | 1993-02-19 | Apparatus and method for measuring the sticking tendency of drilling mud |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB9303321D0 GB9303321D0 (en) | 1993-04-07 |
| GB2275342A true GB2275342A (en) | 1994-08-24 |
| GB2275342B GB2275342B (en) | 1996-08-21 |
Family
ID=10730676
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9303321A Expired - Fee Related GB2275342B (en) | 1993-02-19 | 1993-02-19 | Apparatus and method for measuring the sticking tendency of drilling mud |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2275342B (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2303711A (en) * | 1994-03-29 | 1997-02-26 | Elf Aquitaine | A device for evaluation of the lubricant characteristics of a drilling mud |
| FR2758185A1 (en) * | 1997-01-09 | 1998-07-10 | Schlumberger Cie Dowell | DEVICE AND METHOD FOR MEASURING CHARACTERISTICS OF A PETROLEUM FLUID OR THE LIKE |
| GB2310045B (en) * | 1994-11-21 | 1998-11-04 | Reologica Instr Ab | Rheological measuring device |
| FR2785991A1 (en) * | 1998-11-12 | 2000-05-19 | Schlumberger Cie Dowell | DEVICE AND METHOD FOR MEASURING CHARACTERISTICS OF AN OIL FLUID OR THE LIKE |
| GB2448746A (en) * | 2007-04-26 | 2008-10-29 | Mi Llc | Rheological Measurement Of Filtercake |
| US9109411B2 (en) | 2011-06-20 | 2015-08-18 | Schlumberger Technology Corporation | Pressure pulse driven friction reduction |
| US9222316B2 (en) | 2012-12-20 | 2015-12-29 | Schlumberger Technology Corporation | Extended reach well system |
| US9470055B2 (en) | 2012-12-20 | 2016-10-18 | Schlumberger Technology Corporation | System and method for providing oscillation downhole |
| US9702192B2 (en) | 2012-01-20 | 2017-07-11 | Schlumberger Technology Corporation | Method and apparatus of distributed systems for extending reach in oilfield applications |
| US10113422B2 (en) | 2015-03-10 | 2018-10-30 | Saudi Arabian Oil Company | Determining spotting fluid properties |
| CN109541175A (en) * | 2018-11-20 | 2019-03-29 | 中国地质大学（北京） | A kind of simulation down-hole drilling fluids recycle the device and method to form mud cake |
| US11352545B2 (en) | 2020-08-12 | 2022-06-07 | Saudi Arabian Oil Company | Lost circulation material for reservoir section |
-
1993
- 1993-02-19 GB GB9303321A patent/GB2275342B/en not_active Expired - Fee Related
Cited By (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2303711A (en) * | 1994-03-29 | 1997-02-26 | Elf Aquitaine | A device for evaluation of the lubricant characteristics of a drilling mud |
| GB2303711B (en) * | 1994-03-29 | 1998-06-24 | Elf Aquitaine | Device for evaluation of the lubricating characteristics of a drilling mud |
| GB2310045B (en) * | 1994-11-21 | 1998-11-04 | Reologica Instr Ab | Rheological measuring device |
| US5874665A (en) * | 1994-11-21 | 1999-02-23 | Reologica Instruments Ab | Rheological measuring device |
| FR2758185A1 (en) * | 1997-01-09 | 1998-07-10 | Schlumberger Cie Dowell | DEVICE AND METHOD FOR MEASURING CHARACTERISTICS OF A PETROLEUM FLUID OR THE LIKE |
| WO1998030885A1 (en) * | 1997-01-09 | 1998-07-16 | Sofitech N.V. | Tricyclic indolene substituted oxazolidinones |
| FR2785991A1 (en) * | 1998-11-12 | 2000-05-19 | Schlumberger Cie Dowell | DEVICE AND METHOD FOR MEASURING CHARACTERISTICS OF AN OIL FLUID OR THE LIKE |
| WO2000029845A1 (en) * | 1998-11-12 | 2000-05-25 | Sofitech N.V. | Apparatus and method for measuring the characteristics of an oilfield fluid or the like |
| US6508105B1 (en) * | 1998-11-12 | 2003-01-21 | Schlumberger Technology Corporation | Apparatus and method for measuring the characteristics of an oilfield fluid or the like |
| WO2008132425A1 (en) * | 2007-04-26 | 2008-11-06 | M-I L.L.C. | Rheological measurement of filtercake |
| GB2448746A (en) * | 2007-04-26 | 2008-10-29 | Mi Llc | Rheological Measurement Of Filtercake |
| GB2448746B (en) * | 2007-04-26 | 2012-04-25 | Mi Llc | Rheological measurement of filtercake |
| US8215155B2 (en) | 2007-04-26 | 2012-07-10 | M-I L.L.C. | Rheological measurement of filtercake |
| US9109411B2 (en) | 2011-06-20 | 2015-08-18 | Schlumberger Technology Corporation | Pressure pulse driven friction reduction |
| US9702192B2 (en) | 2012-01-20 | 2017-07-11 | Schlumberger Technology Corporation | Method and apparatus of distributed systems for extending reach in oilfield applications |
| US9470055B2 (en) | 2012-12-20 | 2016-10-18 | Schlumberger Technology Corporation | System and method for providing oscillation downhole |
| US9222316B2 (en) | 2012-12-20 | 2015-12-29 | Schlumberger Technology Corporation | Extended reach well system |
| US10968713B2 (en) | 2012-12-20 | 2021-04-06 | Schlumberger Technology Corporation | System and method for providing oscillation downhole |
| US10113422B2 (en) | 2015-03-10 | 2018-10-30 | Saudi Arabian Oil Company | Determining spotting fluid properties |
| US10472958B2 (en) | 2015-03-10 | 2019-11-12 | Saudi Arabian Oil Company | Determining spotting fluid properties |
| CN109541175A (en) * | 2018-11-20 | 2019-03-29 | 中国地质大学（北京） | A kind of simulation down-hole drilling fluids recycle the device and method to form mud cake |
| US11352545B2 (en) | 2020-08-12 | 2022-06-07 | Saudi Arabian Oil Company | Lost circulation material for reservoir section |
| US11739249B2 (en) | 2020-08-12 | 2023-08-29 | Saudi Arabian Oil Company | Lost circulation material for reservoir section |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9303321D0 (en) | 1993-04-07 |
| GB2275342B (en) | 1996-08-21 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20060219 |