US3802803A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Submersible screw pump
Assignee: Individual
•
Filing: 1973-01-05
•
Granted: 1974-04-09
•
Expires: 1993-01-05
Abstract
Abstract Submersible screw pumps for transferring liquids, substantially viscous liquid containing gas under a high pressure, for example in the process of oil pumpage from deep oil wells or when pumping oil products from reservoirs in which there is provided a drive with a seal and a starting device, coaxially secured stators formed by rigid casings, housing coaxially disposed elastic bushings having inner threads and protected by a safety valve; twin screw rotors of which one has a right-hand thread and the other a left-hand thread and which are connected to the drive shaft and to each other through a flexible coupling with, each screw rotor being eccentrically disposed in the corresponding stator having an extra thread start as compared with the rotor, so that between the threads of the rotor and the stator there are defined closed spaces disposed along the axis of the stator from the intake chamber of each rotor to the common delivery chamber; the length of the elastic bushing of each stator being at least 20 times the cross sectional diameter of the corresponding screw rotor; the oblong elastic bushings being protected from dry friction and excess pressure owing to the fact that the delivery chamber is automatically connected to and disconnected from the intake chambers of the screw rotors by means of a gate and a pilot valve, disposed coaxially in the safety valve, depending on the output of the screw rotors and the pressure within the delivery chamber, in which case the centers of the extreme closed spaces of each rotor adjoining the delivery chamber are located on a common line extending through the axis of the stators and the axis of the rigid member connecting the two heads of universal joints serving as a flexible coupling between the rotors and transmitting torque from one rotor to the other.
Inventors
- 👤 A Bogdanov
- 👤 A Ratov
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 05:53
CPC Classifications
F; F04; F04C; F04C2/00; F04C2/08; F04C2/10; F04C2/107; F04C2/1071; F04C2/1073; F04B; F04B47/00; F04B47/06
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
386 words
A submersible screw pump adapted for operation in an oil well for pumping oil therefrom comprising in combination: a drive provided with a shaft; a starting device mounted on the shaft of said drive; first and second stators mounted in a co-axial relationship with said drive, each of said stators having elastic bushings mounted within a rigid casing; a first screw rotor arranged eccentrically in said first stator, said first stator having an inner screw surface with an extra screw thread as compared to the screw surface of said first screw rotor; a first double universal joint for connecting said starting device with said first screw rotor and transmitting a turning moment; a second screw rotor arranged eccentrically in said second stator, said second stator having an inner screw surface with an extra screw thread compared to the screw surface of said second screw rotor; the direction of the screw surfaces of said second stator and screw rotor being opposite to the direction of the screw surfaces of said first stator and screw rotor; said screw surfaces of said first and second stators and screw rotors being in contact with each other and forming closed spaces disposed along the axes of the stators, the closed spaces to be filled with liquid being pumped; a second double universal joint for coupling said first and second screw rotors, transmitting a turning moment and carrying axial loads due to the pressure of the liquid; at least two intake chambers, one chamber being located at the extreme end of each of said first and second screw rotors and being connected with the space of said oil well; a delivery chamber located between the two other ends of said first and second screw rotors, said second double universal joint being located in this delivery chamber; a safety valve communicating through a channel with said delivery chamber and with the space of the tubing serving for lowering said pump into said well where said pump operates and protecting said pairs of rotors and stators from dry friction and excessive pressure by admitting the oil from the space of said tubing into the space of said well; the length of the bushings of each of the first and second stators being at least 20 times the cross-sectional diameter of the corresponding screw rotor.
Claim 2
Dependent Claim
386 words
A submersible screw pump adapted for operation in an oil well for pumping oil therefrom comprising in combination: a drive provided with a shaft; a starting device mounted on the shaft of said drive; first and second stators mounted in a co-axial relationship with said drive, each of said stators having elastic bushings mounted within a rigid casing; a first screw rotor arranged eccentrically in said first stator, said first stator having an inner screw surface with an extra screw thread as compared to the screw surface of said first screw rotor; a first double universal joint for connecting said starting device with said first screw rotor and transmitting a turning moment; a second screw rotor arranged eccentrically in said second stator, said second stator having an inner screw surface with an extra screw thread compared to the screw surface of said second screw rotor; the direction of the screw surfaces of said second stator and screw rotor being opposite to the direction of the screw surfaces of said first stator and screw rotor; said screw surfaces of said first and second stators and screw rotors being in contact with each other and forming closed spaces disposed along the axes of the stators, the closed spaces to be filled with liquid being pumped; a second double universal joint for coupling said first and second screw rotors, transmitting a turning moment and carrying axial loads due to the pressure of the liquid; at least two intake chambers, one chamber being located at the extreme end of each of said first and second screw rotors and being connected with the space of said oil well; a delivery chamber located between the two other ends of said first and second screw rotors, said second double universal joint being located in this delivery chamber; a safety valve communicating through a channel with said delivery chamber and with the space of the tubing serving for lowering said pump into said well where said pump operates and protecting said pairs of rotors and stators from dry friction and excessive pressure by admitting the oil from the space of said tubing into the space of said well; the length of the bushings of each of the first and second stators being at least 20 times the cross-sectional diameter of the corresponding screw rotor.
Claim 3
Dependent Claim
71 words
The submersible screw pump of claim 1, wherein said first and second stators are formed by rigid sleeves and elastic bushings secured inside said rigid sleeves, the centers of the extreme closed spaces of each screw rotor adjoining said delivery chamber being located along a single line passing through the axis of said first and second stators and the axis of said double universal joint located in the delivery chamber. the
Claim 4
Dependent Claim
67 words
The submersible screw pump of claim 1 wherein each of said first and second double universal joints comprises: two heads, a rigid member interconnecting said heads, an intErnal and external cover for accommodating said heads therebetween, at least two pairs of rollers for pivot connection of said heads with said covers, the pair of said external covers being secured to the adjacent ends of said screw rotors.
Claim 5
Dependent Claim
166 words
The submersible screw pump of claim 3 wherein each said head of said double universal joints comprises two part-spherical surfaces, two symmetrically located truncated cones with their bases adjoining one another and having a taper angle corresponding to the angle of deviation of the axis of said rigid member from the axes of said screw rotors; at least two longitudinal semicylindrical slots on said truncated cones, each said cover accommodating said heads having a part-spherical surface, and at least two longitudinal semicylindrical slots located correspondingly to said longitudinal semicylindrical slots on said heads, said rollers being arranged freely and with a gap in said longitudinal semicylindrical slots of said heads and said covers and having linear contact with the lines of intersection of the surfaces of said truncated cones with the surfaces of said semicylindrical slots of said heads to ensure transmission of the turning moment between said heads and said covers at an angle to the axes of said rigid member and said screw rotors.
Claim 6
Dependent Claim
30 words
The submersible screw pump of claim 3 wherein one pair of said internal or external covers is made integral with the casing of said cover, thus forming a single member.
Claim 7
Dependent Claim
44 words
The submersible screw pump of claim 3 wherein said heads are secured at the ends of said screw rotors and said driving shaft, two of said adjacent internal covers of said double universal joint being interconnected through a bridge to form an integral member.
Claim 8
Dependent Claim
24 words
The submersible screw pump of claim 4 wherein said part-spherical surfaces of said heads and covers are made in the form of changeable inserts.
Claim 9
Dependent Claim
41 words
The submersible screw pump of claim 3 wherein said covers have an opening for mounting said rigid member which is sealed by a sealing cup, the end face of the sealing cup conforming to the end face shape of said cover.
Claim 10
Dependent Claim
29 words
The submersible screw pump of claim 8 wherein the opening in the cover is sealed by an undulated pipe, and inlet and outlet valves are mounted on said cover.
Claim 11
Dependent Claim
43 words
The submersible screw pump of claim 2 wherein said rigid sleeves of the stators are made of metal and have at least two rows of uniformly arranged orifices and grooves on the inner surface and on the end faces of said flexible bushing.
Claim 12
Dependent Claim
134 words
The submersible screw pump of claim 1 wherein said safety valve includes a gate and a guide bushing, a pilot valve bushing having channels for connection with the space of said well, a pilot valve having two transverse diameters for disconnecting the space of said tubing from the space of said well, a hydraulic buffer having a bushing which is provided with a calibrated hole with a gentle transition along a tapered surface from said hole to said pilot valve, said pilot valve moving together with said gate in one direction under the effect of the difference of the forces of the accelerated flows of liquid in said guide bushing and in said buffer bushing and moving in the other direction under the effect of the liquid pressure in the space of said tubing.
Claim 13
Dependent Claim
43 words
The submersible screw pump of claim 11 wherein said hydraulic buffer is disposed on the side opposite to said gate and serves as a limiter restricting the movement of said pilot valve in the direction of motion of the flow of pumped fluid.
Claim 14
Dependent Claim
68 words
The submersible screw pump of claim 12 wherein, in order to prevent a pressure drop within said buffer bushing compared to the pressure in the space of said tubing, between the adjacent end faces of said pilot valve bushing and said buffer bushing there are located symmetrical channels having a cross sectional area equal to a double cross sectional area of said maximum diameter of the pilot valve.
Claim 15
Dependent Claim
102 words
The submersible screw pump of claim 11 wherein, for reducing the effect of the velocity flow of liquid on the velocity of motion of said gate and said pilot valve during the process of starting said pump, said guide bushing has at least two symmetrical slots the dimension of which along the axis of said valve exceeds the length of the generating line of the cylinder of said gate, while the lower step of said slots is spaced from said seat by a distance at least twice as great as said length of the generating line of the cylinder of said gate.
Claim 16
Dependent Claim
82 words
The submersible screw pump of claim 1 wherein said starting device is made in the form of a starting clutch disposed between said drive and said driving shaft and comprising a collar as a driven member, two inner teeth, the end face of said collar on the side of said drive having annular bridges interconnecting the faces of said teeth, and a driving member in the form of two claws and a spring for resetting said claws when said drive is stopped.
Claim 17
Dependent Claim
47 words
The submersible screw pump of claim 15 wherein said bushing of said driven member has apertures located symmetrically relative to each other along the entire length of said teeth and an oblique portion on the inner surface of said collar opposite to said tooth along said aperture.
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) | 1977-04-08 | 1977-10-08 | 1978-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-08 | 1981-10-08 | 1982-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-08 | 1985-10-08 | 1986-04-09 | $7700.00 | Window Closed / Lapsed |