CA2271647A1 - Machine operating according to the moineau principle, especially a drill motor for deep drilling - Google Patents
Machine operating according to the moineau principle, especially a drill motor for deep drilling Download PDFInfo
- Publication number
- CA2271647A1 CA2271647A1 CA 2271647 CA2271647A CA2271647A1 CA 2271647 A1 CA2271647 A1 CA 2271647A1 CA 2271647 CA2271647 CA 2271647 CA 2271647 A CA2271647 A CA 2271647A CA 2271647 A1 CA2271647 A1 CA 2271647A1
- Authority
- CA
- Canada
- Prior art keywords
- outer metal
- metal member
- moineau
- portions
- helical
- 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.)
- Abandoned
Links
- 238000005553 drilling Methods 0.000 title description 4
- 229920001971 elastomer Polymers 0.000 claims abstract description 18
- 239000000806 elastomer Substances 0.000 claims abstract description 16
- 239000002184 metal Substances 0.000 claims abstract description 16
- 239000007788 liquid Substances 0.000 description 5
- 229910000831 Steel Inorganic materials 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 2
- 230000004323 axial length Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000011796 hollow space material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B4/00—Drives for drilling, used in the borehole
- E21B4/02—Fluid rotary type drives
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C2/00—Rotary-piston machines or pumps
- F04C2/08—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
- F04C2/10—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member
- F04C2/107—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member with helical teeth
- F04C2/1071—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member with helical teeth the inner and outer member having a different number of threads and one of the two being made of elastic materials, e.g. Moineau type
- F04C2/1073—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member with helical teeth the inner and outer member having a different number of threads and one of the two being made of elastic materials, e.g. Moineau type where one member is stationary while the other member rotates and orbits
- F04C2/1075—Construction of the stationary member
Landscapes
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Mechanical Engineering (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
- Flexible Shafts (AREA)
- Rotary Pumps (AREA)
Abstract
A Moineau machine has an outer metal member with an inner elastomer lining and a helical inner member. The outer metal member and the inner helical member are rotatable relative to one another. The outer metal member has a helical shape with an axial center axis. The outer metal member as well as the inner elastomer lining have a uniform wall thickness in the axial direction. The outer metal member has a wave-shaped radial cross-section such that between convex portions concave portions are positioned.
Description
Background of the Invention The present invention is based on a machine operating according to the Moineau principle, especially a drill motor for deep drilling, for example, in the field of oil production. It has an outer member with a helical inner member positioned therein, the outer member provided with an inner helical lining consisting of an elastomer for receiving the inner member. The outer member and the inner member are rotatable relative to one another.
The Moineau principle is realized such that the lining of the outer member, in comparison to the core-like inner member, comprises one more helical by extending projection. The Moineau principle is accordingly fulfilled when the elastomer lining has five helically extending projections while the inner member has four helically extending projections.
In known drill motors the outer member in the area of the actual machine is comprised of a cylindrical steel tube having an elastomer lining which is provided with a helical receiving chamber for the inner member. Accordingly, based on the multiple helical design, when viewed in the circumferential direction of the steel tube, the wall thickness of the elastomer lining varies greatly and thus results in differing loads acting on the elastomer. Furthermore, it is desirable in the context of drill motors to be able to use the annular space external to the outer member) i.e., between the motor and the borehole wall, for example) for the purpose of returning the pressure liquid for driving the drill motor and to make this space as large as possible so as to provide a large throughput cross-section.
It is therefore an object of the present invention to fulfill the aforementioned requirements to the greatest possible degree and to provide a special design of the outer member in order to produce favorable cross-sections forthe lining and a transverse extension for the outer member that is as small as possible.
Summary of the Invention As a solution to this object, it is inventively suggested to provide the outer metal member and its elastomer lining such that over their axial extension they each have a respectively substantially identical (unchanging) wall thickness and that, furthermore, the outer metal member, in cross-section, in the circumferential direction has a wave-shape with alternating convex portions and concave portions.
The uniform wall thickness of the elastomer lining provides for a minimal material expenditure and an improved loading of the elastomer. Furthermore, the concave recesses at the exterior of the outer member provide additional space for returning, for example, the pressure liquid for driving the motor. Also, due to the inventive design special advantages result with respect to the stability and also the adaptability of the outer metal member to the longitudinal extension of the borehole when the machine is to be used in boreholes with great longitudinal extension.
Brief Description of the Drawings Further details of the invention will be explained in the following with the aid of the accompanying drawings in which:
Fig. 1 shows a vertical part-sectional view of the drill motor for lowering into a deep borehole, for example, for oil production (down-hole motor);
and Fig. 2 shows a section along the line II-II of Fig. 1.
Description of Preferred Embodiments The present invention will now described in detail with the aid of a specific embodiment utilizing Figs. 1 through 2.
The drill motor is comprised substantially of a stator 1 with end portions 2 providing connecting members and an elastomer lining 3 consisting especially of rubber or a similar material which is adhered (attached) preferably to the inner wall of the mantle 4 of the stator 1.
The active portion of the stator 1 positioned between the end portions 2 can extend over many meters, while the end portions 2 have a relatively short length that is sufficient for attaching connectors, for example, by threading. For example, the upper end portion 2 is used for attaching drilling linkages, while the lower end portion 2 provides the transition to the driven tool, for example, the drill bit and its bearing.
The hollow space 5 enclosed by the elastomer lining 3 receives the rotor 6 which extends in the upward direction with a free end. At the lower end, a coupling member 7 with inner thread is provided to which a jointed shaft etc. can be connected which compensates the eccentric displacement a and provides connection to the tool. For driving the motor, pressure liquid is introduced from above into the upper end portion 2. It rotates the rotor 6 and thus also the tool. It exits the motor in the downward direction and is then guided upwardly between the outer surface of the stator 1 and the inner wall 8 of the borehole. Above ground, further treatment of the pressure liquid is performed.
The mantle 4 of the stator 1 is produced together with the end portions 2 of a cylindrical steel tube having an axial center axis.
Accordingly, the mantle 4 has over its axial length as well as in the circumferential direction (see Fig. 2) substantially the same wall thickness. This is also true for the elastomer lining 3. The active (bearing) thickness of the rubber is thus practically constant.
It is important in this context that the mantle 4 for a five-fold helical design (five helically extending projections) has five circumferentially distributed convex portions or of bulges (projections) 9 between which concave portions 10 are positioned which, on the exterior of the mantle 4, provide helically extending recesses 11 and thus effect an enlargement of the throughput cross-section between the mantle 4 and the inner wall 8 of the borehole. See Fig. 2 showing a radial cross-section.
The rotor 6 has a four-fold helical design (four helically extending projections) and has substantially a cross shape in cross section with four radial projections 12 that are greatly rounded and have steep flanks in order to match the helical design of the mantle 4, i.e., in order to be able to run along the inner surface of the mantle 4.
It is understood that the invention is not limited with respect to the number of helically extending projections. Preferably, stators provided with a four-fold to six-fold helical design are employed.
The smooth tube that is used for producing the stator is deformed only over a portion of its length to form the helical design.
The desired cylindrical end portions 2 are thus portions of the same manufacturing blank for the stator of the machine. The tube designed as disclosed above is then provided with the elastomer lining 3.
The invention is essentially also useful for a pumping operation whereby the rotor movement then conveys a liquid or mud (thick or muddy medium such as drilling mud). Furthermore, it is also within the realm of the present invention to operate the shown machine in reverse, i.e.) the rotor 6 shown in the drawing operates as a stator and the stator 1 in the drawing operates as a rotor.
Preferably, the invention should be applied to down-hole motors because in this field the greatest advantages can be achieved.
Fig. 2 shows that the wave-shape, respectively) the curvature of the convex portions, respectively, the amplitude (radial length) and the wave-length (angular distance) of the convex portions 9, on the one hand, and the concave portions 10, on the other hand are practically identical to one another (relative to a common central circle). The circumferential extension or contour of the portions 9, 10 thus substantially match one another and also match with regard to their radial length.
The specification incorporates by reference the disclosure of German priority document 198 21 867.2 of 15 May 1998.
The present invention is, of course, in no way restricted to the specific disclosure of the specification and drawings, but also encompasses any modifications within the scope of the appended claims.
The Moineau principle is realized such that the lining of the outer member, in comparison to the core-like inner member, comprises one more helical by extending projection. The Moineau principle is accordingly fulfilled when the elastomer lining has five helically extending projections while the inner member has four helically extending projections.
In known drill motors the outer member in the area of the actual machine is comprised of a cylindrical steel tube having an elastomer lining which is provided with a helical receiving chamber for the inner member. Accordingly, based on the multiple helical design, when viewed in the circumferential direction of the steel tube, the wall thickness of the elastomer lining varies greatly and thus results in differing loads acting on the elastomer. Furthermore, it is desirable in the context of drill motors to be able to use the annular space external to the outer member) i.e., between the motor and the borehole wall, for example) for the purpose of returning the pressure liquid for driving the drill motor and to make this space as large as possible so as to provide a large throughput cross-section.
It is therefore an object of the present invention to fulfill the aforementioned requirements to the greatest possible degree and to provide a special design of the outer member in order to produce favorable cross-sections forthe lining and a transverse extension for the outer member that is as small as possible.
Summary of the Invention As a solution to this object, it is inventively suggested to provide the outer metal member and its elastomer lining such that over their axial extension they each have a respectively substantially identical (unchanging) wall thickness and that, furthermore, the outer metal member, in cross-section, in the circumferential direction has a wave-shape with alternating convex portions and concave portions.
The uniform wall thickness of the elastomer lining provides for a minimal material expenditure and an improved loading of the elastomer. Furthermore, the concave recesses at the exterior of the outer member provide additional space for returning, for example, the pressure liquid for driving the motor. Also, due to the inventive design special advantages result with respect to the stability and also the adaptability of the outer metal member to the longitudinal extension of the borehole when the machine is to be used in boreholes with great longitudinal extension.
Brief Description of the Drawings Further details of the invention will be explained in the following with the aid of the accompanying drawings in which:
Fig. 1 shows a vertical part-sectional view of the drill motor for lowering into a deep borehole, for example, for oil production (down-hole motor);
and Fig. 2 shows a section along the line II-II of Fig. 1.
Description of Preferred Embodiments The present invention will now described in detail with the aid of a specific embodiment utilizing Figs. 1 through 2.
The drill motor is comprised substantially of a stator 1 with end portions 2 providing connecting members and an elastomer lining 3 consisting especially of rubber or a similar material which is adhered (attached) preferably to the inner wall of the mantle 4 of the stator 1.
The active portion of the stator 1 positioned between the end portions 2 can extend over many meters, while the end portions 2 have a relatively short length that is sufficient for attaching connectors, for example, by threading. For example, the upper end portion 2 is used for attaching drilling linkages, while the lower end portion 2 provides the transition to the driven tool, for example, the drill bit and its bearing.
The hollow space 5 enclosed by the elastomer lining 3 receives the rotor 6 which extends in the upward direction with a free end. At the lower end, a coupling member 7 with inner thread is provided to which a jointed shaft etc. can be connected which compensates the eccentric displacement a and provides connection to the tool. For driving the motor, pressure liquid is introduced from above into the upper end portion 2. It rotates the rotor 6 and thus also the tool. It exits the motor in the downward direction and is then guided upwardly between the outer surface of the stator 1 and the inner wall 8 of the borehole. Above ground, further treatment of the pressure liquid is performed.
The mantle 4 of the stator 1 is produced together with the end portions 2 of a cylindrical steel tube having an axial center axis.
Accordingly, the mantle 4 has over its axial length as well as in the circumferential direction (see Fig. 2) substantially the same wall thickness. This is also true for the elastomer lining 3. The active (bearing) thickness of the rubber is thus practically constant.
It is important in this context that the mantle 4 for a five-fold helical design (five helically extending projections) has five circumferentially distributed convex portions or of bulges (projections) 9 between which concave portions 10 are positioned which, on the exterior of the mantle 4, provide helically extending recesses 11 and thus effect an enlargement of the throughput cross-section between the mantle 4 and the inner wall 8 of the borehole. See Fig. 2 showing a radial cross-section.
The rotor 6 has a four-fold helical design (four helically extending projections) and has substantially a cross shape in cross section with four radial projections 12 that are greatly rounded and have steep flanks in order to match the helical design of the mantle 4, i.e., in order to be able to run along the inner surface of the mantle 4.
It is understood that the invention is not limited with respect to the number of helically extending projections. Preferably, stators provided with a four-fold to six-fold helical design are employed.
The smooth tube that is used for producing the stator is deformed only over a portion of its length to form the helical design.
The desired cylindrical end portions 2 are thus portions of the same manufacturing blank for the stator of the machine. The tube designed as disclosed above is then provided with the elastomer lining 3.
The invention is essentially also useful for a pumping operation whereby the rotor movement then conveys a liquid or mud (thick or muddy medium such as drilling mud). Furthermore, it is also within the realm of the present invention to operate the shown machine in reverse, i.e.) the rotor 6 shown in the drawing operates as a stator and the stator 1 in the drawing operates as a rotor.
Preferably, the invention should be applied to down-hole motors because in this field the greatest advantages can be achieved.
Fig. 2 shows that the wave-shape, respectively) the curvature of the convex portions, respectively, the amplitude (radial length) and the wave-length (angular distance) of the convex portions 9, on the one hand, and the concave portions 10, on the other hand are practically identical to one another (relative to a common central circle). The circumferential extension or contour of the portions 9, 10 thus substantially match one another and also match with regard to their radial length.
The specification incorporates by reference the disclosure of German priority document 198 21 867.2 of 15 May 1998.
The present invention is, of course, in no way restricted to the specific disclosure of the specification and drawings, but also encompasses any modifications within the scope of the appended claims.
Claims (5)
1. A Moineau machine comprising:
an outer metal member (4) having an inner elastomer lining (3);
a helical inner member (6);
said outer metal member (4) and said inner helical member (6) rotatable relative to one another;
said outer metal member (4) having a helical shape with an axial center axis;
said outer metal member (4) having a uniform wall thickness in a direction of said axial center axis;
said inner elastomer lining (3) having a uniform wall thickness in a direction of said axial center axis;
said outer metal member (4) having a wave-shaped radial cross-section such that between convex portions (9) concave portions (10) are positioned.
an outer metal member (4) having an inner elastomer lining (3);
a helical inner member (6);
said outer metal member (4) and said inner helical member (6) rotatable relative to one another;
said outer metal member (4) having a helical shape with an axial center axis;
said outer metal member (4) having a uniform wall thickness in a direction of said axial center axis;
said inner elastomer lining (3) having a uniform wall thickness in a direction of said axial center axis;
said outer metal member (4) having a wave-shaped radial cross-section such that between convex portions (9) concave portions (10) are positioned.
2. A Moineau machine according to claim 1, wherein said convex portions (9) and said concave portions (10) extend over identical angular distances and have a maximum height spaced at identical radial spacing from a central circle extending through said wave-shaped cross-section.
3. A Moineau machine according to claim 1, wherein said wave-shaped cross-section of said outer metal member (4) has two to seven of said convex portions (9) and wherein said inner helical member (6) has radial projections (12) having a greater curvature than said convex portions (9) with steeper flanks than said convex portions (9).
4. A Moineau machine according to claim 1, wherein said outer metal member (4) has axial portions (2) that are cylindrical.
5. A Moineau machine according to claim 4, wherein said axial portions are end portions (2) of said outer metal member (4).
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19821867.2 | 1998-05-15 | ||
| DE1998121867 DE19821867A1 (en) | 1998-05-15 | 1998-05-15 | Downhole deep drilling motor based on eccentric mono-pump principle |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2271647A1 true CA2271647A1 (en) | 1999-11-15 |
Family
ID=7867909
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2271647 Abandoned CA2271647A1 (en) | 1998-05-15 | 1999-05-14 | Machine operating according to the moineau principle, especially a drill motor for deep drilling |
Country Status (4)
| Country | Link |
|---|---|
| CA (1) | CA2271647A1 (en) |
| DE (1) | DE19821867A1 (en) |
| FR (1) | FR2778700B1 (en) |
| GB (1) | GB2339598B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9416780B2 (en) | 2007-01-24 | 2016-08-16 | Halliburton Energy Services, Inc. | Electroformed stator tube for a progressing cavity apparatus |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6604921B1 (en) * | 2002-01-24 | 2003-08-12 | Schlumberger Technology Corporation | Optimized liner thickness for positive displacement drilling motors |
| RU2228444C1 (en) * | 2003-03-25 | 2004-05-10 | Общество с ограниченной ответственностью фирма "Радиус-Сервис" | Screw hydraulic machine gerotor mechanism |
| US7686100B2 (en) | 2006-08-02 | 2010-03-30 | Schlumberger Technology Corporation | Technique and apparatus for drilling and completing a well in one half trip |
| JP2017506308A (en) | 2014-02-18 | 2017-03-02 | バート ローターズ ユーケー リミテッドＶｅｒｔ Ｒｏｔｏｒｓ Ｕｋ Ｌｉｍｉｔｅｄ | Positive displacement rotary machine |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL6815412A (en) * | 1967-11-02 | 1969-05-06 | ||
| GB2059481B (en) * | 1979-09-21 | 1983-03-16 | Shell Int Research | Hydraulically powered drilling sub for deepwell drilling |
| DE4006339C2 (en) * | 1990-03-01 | 1994-08-04 | Gd Anker Gmbh & Co Kg | Stator for an eccentric screw pump |
| GB2244517B (en) * | 1990-05-31 | 1994-05-04 | Mono Pumps Ltd | Helical gear pump and stator |
| US5171138A (en) * | 1990-12-20 | 1992-12-15 | Drilex Systems, Inc. | Composite stator construction for downhole drilling motors |
| HU207569B (en) * | 1990-12-20 | 1993-04-28 | Drilex Syst Inc | Hydraulis engine |
| DE4134853C1 (en) * | 1991-05-22 | 1992-11-12 | Netzsch-Mohnopumpen Gmbh, 8264 Waldkraiburg, De | |
| US5221197A (en) * | 1991-08-08 | 1993-06-22 | Kochnev Anatoly M | Working member of a helical downhole motor for drilling wells |
| US5759019A (en) * | 1994-02-14 | 1998-06-02 | Steven M. Wood | Progressive cavity pumps using composite materials |
-
1998
- 1998-05-15 DE DE1998121867 patent/DE19821867A1/en not_active Withdrawn
-
1999
- 1999-04-30 FR FR9905510A patent/FR2778700B1/en not_active Expired - Fee Related
- 1999-05-07 GB GB9910602A patent/GB2339598B/en not_active Expired - Fee Related
- 1999-05-14 CA CA 2271647 patent/CA2271647A1/en not_active Abandoned
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9416780B2 (en) | 2007-01-24 | 2016-08-16 | Halliburton Energy Services, Inc. | Electroformed stator tube for a progressing cavity apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2778700A1 (en) | 1999-11-19 |
| DE19821867A1 (en) | 1999-11-18 |
| GB2339598B (en) | 2002-11-13 |
| GB9910602D0 (en) | 1999-07-07 |
| FR2778700B1 (en) | 2002-01-18 |
| GB2339598A (en) | 2000-02-02 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Dead |