CN103878547A - Method for machining screw type oil well pump stator - Google Patents
Method for machining screw type oil well pump stator Download PDFInfo
- Publication number
- CN103878547A CN103878547A CN201410084489.5A CN201410084489A CN103878547A CN 103878547 A CN103878547 A CN 103878547A CN 201410084489 A CN201410084489 A CN 201410084489A CN 103878547 A CN103878547 A CN 103878547A
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- Prior art keywords
- steel pipe
- mold
- screw type
- type oil
- stator
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
- B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
- B21D26/033—Deforming tubular bodies
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
- B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
- B21D26/033—Deforming tubular bodies
- B21D26/047—Mould construction
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/08—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Fluid Mechanics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Rotary Pumps (AREA)
- Details And Applications Of Rotary Liquid Pumps (AREA)
Abstract
The invention discloses a method for machining a screw type oil well pump stator. The method for machining the screw type oil well pump stator comprises the steps that S1, primary forming is conducted on a steel pipe through an outer die with the inner surface being a preset spiral curved surface till the outer wall of the steel pipe is closely attached to the inner surface of the outer die; S2, secondary forming is conducted on the steel pipe processed in the step S1 through an inner die with the outer surface being a preset spiral curved surface till the inner wall of the steel pipe is closely attached to the outer surface of the inner die; S3, quenching, annealing and hard chromium plating are conducted on the steel pipe processed in the step S2, and finally the screw type oil well pump stator is obtained. The stator obtained through the method does not need to be provided with a lining, and the defects that a rubber lining is prone to aging and low in operating temperature can be overcome; meanwhile, the screw type oil well pump stator obtained through the method has the advantage that the matching accuracy between stators / rotors is high.
Description
Technical field
The present invention relates to field mining equipment manufacture, be specifically related to a kind of processing method of screw type oil-well stator.
Background technology
Screw type oil-well (screw-pump) is invented by Frenchman Le Neimuwanuo (Ren é Moineau) at eighties of last century the '20s, originally be applied in pump, compressor mechanical or motor, until eighties of last century the eighties, screw type oil-well is just used as the artificial lift equipment of petroleum industry, and from middle nineteen nineties, be used widely.
The moving component of screw type oil-well is few, there is no valve member and complicated runner, and oily flow disturbance is little, and flow is even, in exploitation high viscosity, high during containing sand and the larger crude oil of air content, with other pumping units compare have advantages of unique.As shown in Figure 1, its main working parts is screw stator 1 and rotor 2 to typical screw type oil-well structure.Wherein, stator 1 comprises pump barrel 11 and lining 12, and lining 12 generally for example, forms at pump barrel 11 inner surface cast elastomeric materials (acrylonitrile-butadiene rubber).
But there is following shortcoming in conventional screw type oil-well: on the one hand, the chemical substance as the elastomeric material of lining 12 easily and in oil reacts and aging, and its operating temperature is also limited; On the other hand, rubber bushing 12 inner surfaces are spiral cambers of became uneven, and as shown in Figure 1, in the time that screw type oil-well is worked, rotor 2 rubs and impacts generation heat energy with stator 1, can make the inner chamber of stator 1 diminish, and increases friction loss, thereby reduces mechanical efficiency.Therefore, these shortcomings have seriously restricted life-span and the efficiency of screw type oil-well.
Summary of the invention
Given this, the object of the invention is to propose a kind of processing method of screw type oil-well stator, this oil well pump stator is without using lining, and its inner surface directly contacts with rotor, thereby improves life-span and the operating efficiency of screw type oil-well.
For realizing above goal of the invention, the present invention by the following technical solutions:
A kind of screw type oil-well processing method of stator, comprises the following steps:
S1, to utilize inner surface be that the outer mold of predetermined spiral camber carries out once-forming to steel pipe, wherein, steel pipe is inserted in to the inner chamber of outer mold and uses fixture to fix and seal steel pipe two ends, then, liquid is injected to steel pipe makes it be full of steel pipe inner chamber, finally, the pressure that increases liquid radially expands steel pipe, until the inner surface of outer wall of steel pipe and outer mold fits tightly;
S2, utilize outer surface be described predetermined spiral camber inner mold to through step S1 process steel pipe carry out secondary forming, wherein, inner mold is inserted in to the inner chamber of the steel pipe to processing through step S1, then, steel pipe is placed in to the hydraulic cavities of sealing, to filling liquid in hydraulic cavities, increases fluid pressure, steel pipe is radially compressed, until the laminating of the intimate of steel pipe inner wall and inner mold;
S3, to the steel pipe of processing through step S2 quench, annealing and hard chrome plating processing, finally obtain screw type oil-well stator, wherein, steel pipe uses the steel of 0.75～0.85%C, 0.15～0.3%Si, 0.15～0.35%Mn, 1.0～1.6%Cr, steel pipe after treatment step S2 is heated to 820～840 DEG C to quench, then at 760～800 DEG C of temperature, anneal, finally carry out hard chrome plating processing, at inner wall surface plating one deck chrome plating of steel pipe.
Compared with prior art, the present invention has following beneficial effect: due to without use lining, utilize the screw type oil-well that manufacture method of the present invention obtains can overcome the easily aging and low shortcoming of operating temperature of rubber bushing, meanwhile, also there is fixed/rotor quality of fit compared with advantages of higher.
Brief description of the drawings
With reference to explanation below, by reference to the accompanying drawings, can there is best understanding to the present invention.In the accompanying drawings, identical part can be represented by identical label.
Fig. 1 is the structural representation of conventional screw formula oil well pump;
Fig. 2 is the processing method of stator flow process of the embodiment of the present invention;
Fig. 3 is that the embodiment of the present invention utilizes outer mold to carry out the schematic diagram of once-forming;
Fig. 4 is the steel pipe shape schematic diagram after embodiment of the present invention once-forming;
Fig. 5 is that the embodiment of the present invention utilizes inner mold to carry out the schematic diagram of secondary forming.
Detailed description of the invention
In order to make object of the present invention, technical scheme and advantage clearer, below in conjunction with accompanying drawing and exemplary embodiment, the present invention is further elaborated.Should be appreciated that exemplary embodiment described herein is only in order to explain the present invention, the scope of application being not intended to limit the present invention.
As shown in Figure 2, the screw type oil-well processing method of stator of the embodiment of the present invention, comprises the following steps:
S1, to utilize inner surface be that the outer mold of predetermined spiral camber carries out once-forming to steel pipe.
As shown in Figure 3, outer mold 4 can be assembling die, is divided into upper and lower two parts, when work, upper and lower two parts are combined and fixed, thereby the inner surface 41 of a complete helix curved surface is provided, and after fixing, the shortest internal diameter of this inner surface 41 should be slightly larger than the external diameter of steel pipe 3.Assembling die has advantages of the assembly and disassembly of being convenient to, but in the time that steel pipe 3 is formed, need to use external force that upper and lower two parts are fixed together, and easily occurs becoming flexible, thereby be difficult to ensure forming quality between die assembly.As preferably, can use the unitary mould of drum, the predetermined spiral camber of its inner surface 41 for needing, outer surface be the face of cylinder (in fact, outer surface also can not require), and as previously mentioned, the shortest internal diameter of inner surface 41 should be slightly larger than the external diameter of steel pipe.Wherein, select to have as required the mould of different spiral camber inner surfaces 41.Due to many 1 of the stator specific lobe rotor head number of screw type oil-well, therefore the inner surface of stator is generally double helix curved surface or many spiral cambers.
No matter outer mold adopts combined type or monoblock type, when work, steel pipe 3 is inserted in to the inner chamber of outer mold 4 and uses fixture 5 to fix and seal steel pipe 3 two ends, then, liquid (not shown) is injected to steel pipe 3 and make it be full of steel pipe inner chamber, last, the pressure that increases liquid radially expands steel pipe 3, until the inner surface of steel pipe 3 outer walls and outer mold 4 fits tightly, as shown in Figure 4.Thus, steel pipe 3 is that inside and outside wall is the shape of spiral camber by preparatory processing.Wherein, liquid can adopt water or hydraulic oil.In a particular embodiment, can one hydraulic stem 6 be respectively set vertically in fixture 5 central authorities at steel pipe 3 two ends, utilize drive unit to drive two hydraulic stem 6 move toward one another, thereby the liquid of compression steel duct increases fluid pressure, realize hydraulic pressure processing.It may be noted that hydraulic pressure processing is prior art, be widely used in automobile, airplane component manufacture process.Compared with the processing method such as electrolysis, broaching, form milling, hydraulic pressure processing has that technique is simple, efficiency is compared with advantages of higher.
In addition, in forming process, steel pipe 3 and/or liquid (particularly hydraulic oil) can be heated, and to improve the ductility of steel, thereby reduce the pressure that hydraulic pressure machining needs.For example, can adopt electrically heated method to steel pipe 3, steel pipe 3 be imposed the electric current of some strength, now steel pipe 3 is equivalent to a resistance, and electric current flows through this equivalent resistance and produces heat energy.
S2, utilize outer surface be described predetermined spiral camber inner mold to through step S1 process steel pipe carry out secondary forming.
In the forming process of step S1, outer mold 4 is fitted with the intimate of steel pipe 3, can ensure in theory higher machining accuracy.But in real work, screw type oil-well rotor is to contact with the inner surface of stator, therefore, need to guarantee that the stator inner surface that last processing obtains has good precision.For this reason, need to utilize inner mold to carry out secondary forming to steel pipe 3.
As shown in Figure 5, inner mold 7 is generally monolithic mold, and its outer surface is the spiral camber identical with the inner surface of outer mold 4, and its maximum outside diameter should be slightly less than the minimum diameter of steel pipe 3 after step S1 processes.When work, inner mold 7 is inserted in to the inner chamber of steel pipe 3, then, steel pipe 3 is placed in to the hydraulic cavities 8 of sealing, to filling liquid (water or hydraulic oil) in hydraulic cavities, increases fluid pressure, steel pipe 3 is radially compressed, until the laminating of the intimate of steel pipe 3 inwalls and inner mold 7.Thus, can ensure that steel pipe 3 inwalls have higher precision.
After hydraulic pressure machines, due to the existence of steel pipe 3 internal stress, between steel pipe 3 inwalls and inner mold 7, in fact still can there is certain space, therefore, can between steel pipe 3 inwalls and inner mold 7, inject lubricant, after sufficient lubrication, then along hand of spiral rotation inner mold 7, make its slowly motion vertically, it takes out from steel pipe 3 the most at last.
S3, to the steel pipe of processing through step S2 quench, annealing and hard chrome plating processing, finally obtain screw type oil-well stator.
After step S2 processes, stator is preliminarily forming, but also needs stator to carry out cure process, to improve its abrasion resistance, extends working life.
Owing to having passed through forming process twice, the precision of the stator (especially inner surface) that final processing obtains is guaranteed, can be without using lining, and its inner surface directly contacts with rotor, is assembled into screw type oil-well.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, all any amendments of doing within the spirit and principles in the present invention, be equal to and replace and improvement etc., within all should being included in protection scope of the present invention.
Claims (6)
1. a screw type oil-well processing method of stator, comprises the following steps:
S1, to utilize inner surface be that the outer mold of predetermined spiral camber carries out once-forming to steel pipe, wherein, steel pipe is inserted in to the inner chamber of outer mold and uses fixture to fix and seal steel pipe two ends, then, liquid is injected to steel pipe makes it be full of steel pipe inner chamber, finally, the pressure that increases liquid radially expands steel pipe, until the inner surface of outer wall of steel pipe and outer mold fits tightly;
S2, utilize outer surface be described predetermined spiral camber inner mold to through step S1 process steel pipe carry out secondary forming, wherein, inner mold is inserted in to the inner chamber of the steel pipe to processing through step S1, then, steel pipe is placed in to the hydraulic cavities of sealing, to filling liquid in hydraulic cavities, increases fluid pressure, steel pipe is radially compressed, until the laminating of the intimate of steel pipe inner wall and inner mold;
S3, to the steel pipe of processing through step S2 quench, annealing and hard chrome plating processing, finally obtain screw type oil-well stator, wherein, described steel pipe uses the steel of 0.75～0.85%C, 0.15～0.3%Si, 0.15～0.35%Mn, 1.0～1.6%Cr, steel pipe after treatment step S2 is heated to 820～840 DEG C to quench, then at 760～800 DEG C of temperature, anneal, finally carry out hard chrome plating processing, at inner wall surface plating one deck chrome plating of steel pipe.
2. method according to claim 1, in step S1, described outer mold is combined type or monolithic mold.
3. method according to claim 1, in step S1, steel pipe and/or liquid are heated, to improve the ductility of steel.
4. method according to claim 3, wherein, carries out electrical heating to steel pipe, steel pipe is imposed the electric current of some strength, makes electric current flow through this steel pipe and produces heat energy.
5. method according to claim 1, in step S2, described inner mold is generally monolithic mold.
6. method according to claim 1, in step S3, described chrome plating thickness is preferably 20～30 μ m.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410084489.5A CN103878547B (en) | 2014-03-10 | 2014-03-10 | A kind of processing method of screw type oil-well stator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410084489.5A CN103878547B (en) | 2014-03-10 | 2014-03-10 | A kind of processing method of screw type oil-well stator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103878547A true CN103878547A (en) | 2014-06-25 |
| CN103878547B CN103878547B (en) | 2016-09-14 |
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|---|---|---|---|
| CN201410084489.5A Expired - Fee Related CN103878547B (en) | 2014-03-10 | 2014-03-10 | A kind of processing method of screw type oil-well stator |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104874978A (en) * | 2015-04-17 | 2015-09-02 | 中石化石油工程机械有限公司研究院 | Machining method for all-metal screw stator |
| CN104907383A (en) * | 2015-06-25 | 2015-09-16 | 王海燕 | Equal wall thickness threaded rod pump stator pipe manufacturing method |
| CN106216465A (en) * | 2016-08-11 | 2016-12-14 | 黑龙江优珈科技有限公司 | A kind of novel inside and outside screw pump stator tube with uniform wall thickness and preparation facilities and method |
| CN108555107A (en) * | 2018-05-14 | 2018-09-21 | 西南石油大学 | Equal wall thickness metal stator bushing machinery is outer to be squeezed and fluid Inner pressurization compound forming processing methods |
Citations (8)
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| DE2240423A1 (en) * | 1972-08-17 | 1974-03-07 | Hermetic Pumpen Gmbh | CONVEYOR DEVICE, IN PARTICULAR CONVEYOR PUMP |
| CN1729361A (en) * | 2002-10-21 | 2006-02-01 | 诺埃提克工程公司 | Stator of a moineau-pump |
| US20090110579A1 (en) * | 2007-10-31 | 2009-04-30 | Moyno, Inc. | Equal wall stator |
| CN101927291A (en) * | 2009-06-22 | 2010-12-29 | 宝山钢铁股份有限公司 | Pre-forming method for tube hydroforming and device thereof |
| CN102133596A (en) * | 2010-01-27 | 2011-07-27 | 宁波市华涛不锈钢管材有限公司 | Inside high-pressure molding method and device of thin-wall stainless steel tube |
| CN102139440A (en) * | 2011-04-13 | 2011-08-03 | 新疆华易石油工程技术有限公司 | Machining method for stator of all-metal screw pump for thickened-oil thermal exploitation |
| CN102501016A (en) * | 2011-11-04 | 2012-06-20 | 中国海洋石油总公司 | Method for machining all-metal screw pump stator |
| CN202506711U (en) * | 2011-12-26 | 2012-10-31 | 大连环友屏蔽泵有限公司 | Reshaping mould for stator shielding sleeve of shielding pump |
-
2014
- 2014-03-10 CN CN201410084489.5A patent/CN103878547B/en not_active Expired - Fee Related
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2240423A1 (en) * | 1972-08-17 | 1974-03-07 | Hermetic Pumpen Gmbh | CONVEYOR DEVICE, IN PARTICULAR CONVEYOR PUMP |
| CN1729361A (en) * | 2002-10-21 | 2006-02-01 | 诺埃提克工程公司 | Stator of a moineau-pump |
| US20090110579A1 (en) * | 2007-10-31 | 2009-04-30 | Moyno, Inc. | Equal wall stator |
| CN101927291A (en) * | 2009-06-22 | 2010-12-29 | 宝山钢铁股份有限公司 | Pre-forming method for tube hydroforming and device thereof |
| CN102133596A (en) * | 2010-01-27 | 2011-07-27 | 宁波市华涛不锈钢管材有限公司 | Inside high-pressure molding method and device of thin-wall stainless steel tube |
| CN102139440A (en) * | 2011-04-13 | 2011-08-03 | 新疆华易石油工程技术有限公司 | Machining method for stator of all-metal screw pump for thickened-oil thermal exploitation |
| CN102501016A (en) * | 2011-11-04 | 2012-06-20 | 中国海洋石油总公司 | Method for machining all-metal screw pump stator |
| CN202506711U (en) * | 2011-12-26 | 2012-10-31 | 大连环友屏蔽泵有限公司 | Reshaping mould for stator shielding sleeve of shielding pump |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104874978A (en) * | 2015-04-17 | 2015-09-02 | 中石化石油工程机械有限公司研究院 | Machining method for all-metal screw stator |
| CN104874978B (en) * | 2015-04-17 | 2017-04-12 | 中石化石油工程机械有限公司研究院 | Machining method for all-metal screw stator |
| CN104907383A (en) * | 2015-06-25 | 2015-09-16 | 王海燕 | Equal wall thickness threaded rod pump stator pipe manufacturing method |
| CN106216465A (en) * | 2016-08-11 | 2016-12-14 | 黑龙江优珈科技有限公司 | A kind of novel inside and outside screw pump stator tube with uniform wall thickness and preparation facilities and method |
| CN108555107A (en) * | 2018-05-14 | 2018-09-21 | 西南石油大学 | Equal wall thickness metal stator bushing machinery is outer to be squeezed and fluid Inner pressurization compound forming processing methods |
| CN108555107B (en) * | 2018-05-14 | 2023-10-24 | 西南石油大学 | Mechanical external extrusion and fluid internal pressure composite forming processing method for equal-wall-thickness metal stator bushing |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103878547B (en) | 2016-09-14 |
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Granted publication date: 20160914 |