US 3551620 A
Description (OCR text may contain errors)
United States Patent  Inventor Jimmie N. Hoover 2517 Cambridge St., Odessa, Tex. 79760 [21 1 Appl. No. 807,290  Filed Mar. 14, 1969  Patented Dec. 29. 1970  FLOW, NO-FLOW DEVICE 10 Claims, 1 Drawing Fig.
 US. Cl 200/83, 340/244  Int. Cl i. H01h 35/40  Field of Search 18/16; 73/151, 239. 240; 103/25; ZOO/81.9; 340/244, 245; 200/83; 73/209  References Cited UNITED STATES PATENTS 3.276.380 10/1966 Stevenson 200/81.9X 2,892,051 6/1959 Moore ZOO/81.9(M)
Primary ExaminerRobert K. Schaefer Assistant Examiner-J. R. Scott Attorney-Marcus L. Bates ABSTRACT: A flow, no-flow device which differentiates between gas and liquid fluid flow therethrough The device includes a movable element which cooperates with an orifice in a manner similar to a valve element and valve seat. The movable element remains in the opened position when liquid is flowing therethrough and assumes the closed position upon the occurrence of gaseous fluid flowing therethrough. A switch associated with the movable element of the device is adapted to interrupt the current flow to a motor of a pump which provides the source of fluid flow, thus obviating a pump-off condition in a well bore.
PATENTEU UEC29 19m FIG. 5
INVENTOR. JIMMIE N. HOOVER BY MARCUS L. BATES FIG. 6
FLOW, NO-FLOW DEVICE BACKGROUND OF THE INVENTION In the production of oil wells by artificial lift, such as a bottom hole pump which is actuated by a pump jack located above the surface of the earth, a sucker rod is attached to the pump so as to deliver reciprocatory motion from the pump jack to the downhole pump. The sucker rod is attached to the pump jack by, a polish rod, anda stuffing box seals the reciprocating polish rod to the fixed free end of the production tubing. The produced crude sufiiciently lubricates the seal between the packing of the stuffing box and the polish rod. The pump cyclically unloads the reservoir, causing gaseous fluid to be produced, whereupon the gas is flow conducted past the seal provided by the stufiing box. This action causes rapid and excessive wear to occur between the polish rod and stuffing box because of the lack of lubrication and coolant normally provided bythe produced crude. Accordingly, it is advantageous to be able to discontinue the operation of the pump jack motor upon a substantial amount of gaseous fluid being produced from the well. This discontinuance of opera- :ion is referred to as "pump-off control." Such an expedient to! only minimizes wear upon the various components of the Jump system. but also effects a savings in electric power.
Various mechanical and electromechanical devices have been suggested by the prior art in order to avoid continued operation of a pump jack upon the detection of a substantial flow of gaseous fluid flow. One such prior art device which has proven highly satisfactory is the apparatus described in U.S. Pat. No. 3,105,433 to Johnson.
Another form of the prior art devices which provides a pump-off control relates to measuring the tension on the sucker rod in order to ascertain the static head of produced fluid within the production tubing as described in U.S. Pat.
No. 3,359,791 to Pantages. As evidenced by these and other known forms of the prior art devices directed to flow, no-flow of liquid from an oil well, a substantial amount of circuitry and apparatus of a complicated nature is generally required.
SUMMARY OF THE INVENTION The present invention provides a pumpoff control means for effectively discriminating between gaseous and liquid fluid flow by providing a .flow,v no-flow apparatus having .a main housing within which there is operatively positioned a flow responsive or movable element which together with the housing forms an upper and a lower chamber. An equalizer line connected between each of the chambers forms a stand pipe. A passageway in the form of a gas orifice is provided within the flow responsive element for equalizing the pressure between the two chambers when gas if flowing. A switch means adapted to be moved in response to movement of the movable element provides a control for interrupting current flow to the motor which actuates a downhole pump. Flow of produced liquid through the inlet and to the lower chamber provides a hydrostatic head in the equalizer line which is effected as an upwardly directed force on the movable element to thereby lift the element from the orifice. Thisaction maintains the switch in the closed or current-flowing condition. When the reservoir produces a substantial quantity of gas rather than liquid or a liquid/gas mixture, the gaseous flow into the housing causes the liquid level in the equalizer line to be lowered and the gas to flow into the upper chamber and through the flow control element, thereby equalizing the pressure between the two chambers. This action causes the biased movable element to be seated against the orifice thereby moving the switch to the opened position so as to interrupt current flow to the downhole pump motor whereupon no further pumping action is possible until the pump is again energized.
; It is therefore a primary object of the present invention to provide a flow, no-flow device which produces a signal when liquid or a mixture of liquid and gases is flowing through a conduit.
A further object of the invention is to provide an improved fiow, no-flow device which actuates a flow control means when liquid is flowing through a conduit. and which deenergizes the flow control means when gas is flowing through the conduit.
A still further object of the present invention is to provide an improved flow, no-fiow device which prevents a pump-off condition from occurring in an oil well.
Another object of the present invention is to provide a flow. no-flow device having a movable element therein responsive to a hydrostatic head within structure related to the movable element.
These and other objects are attained in accordance with the present invention by the provision of a flow, no-flow device fabricated essentially as set forth in the above abstract and summary. Other objects will occur to those skilled in the art upon digesting the remainder of the disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 4 is a fragmentary cross-sectional view taken along line 4-4 of FIG. 3;
FIG. 5 is a partly cross-sectional view taken along line 5-5 of FIG. 1; and FIG. 6 is a schematical representation illustrating a contemplated use of the invention. A
DESCRIPTION OF THE PREFERRED EMBODIMENT There is disclosed in FIG. 1, in conjunction with the remaining FIGS, a flow, no-flow device made in accordance with the present invention. The device includes a main housing within which is disposed an inlet 12, an outlet 14, and with an orifice l6 interposed between the inlet and outlet. An upper portion 18 of the housing is suitably attached, as by the illustrated flange ring and bolt circle, to the lower portion ofthe housing. Upwardly depending from the upper portion of the housing is a stand pipe housing 20. A flexible diaphragm 22 is interposed between the flange faces of the upper and lower housing members and divides the interior of the main housing into an inlet chamber 24, an outlet chamber 25, and an upper chamber 26. A movable element 28 has a lower face 30 which is preferably a resilient seal material that enables the movable element to cooperate with the upwardly depending edge portion of the before-mentioned orifice. A metal disc 32 is removably attached to the movable element by any suitable means in order to secure the before-mentioned diaphragm thereto.
Upwardly depending from the movable element is a stand pipe, or equalizer conduit 34, which is concentrically arranged with respect to the before-mentioned stand pipe housing. The movable element is provided with a passageway 36 which communicates with passageway 38 formed within the tubular stand pipe. Spaced-apart from the terminal end of the upper extremity of the stand pipe are a series of radially spaced-apart ports or apertures 40 which communicate the interior of the stand pipe with the interior of the stand pipe housing.
An isolated reed switch housing 46 is supportingly attached to the stand pipe housing and telescopingly received in a slidable manner within the stand pipe itself.
The movable element is further provided with a multiplicity of vertically disposed passageways 44 which communicate the upper chamber with the outlet chamber regardless of the position of the movable element.
The annulus at 46 can be made of close tolerance if desired, however, such an expedient is not deemed necessary unless the stand pipe outle holes are located in a manner whereby the device seen in FIGS. 1 and 2 as seen along line 3-3 of FIG.
' they become covered by the lower terminal end of the isolated reed switch housing. A permanent magnet 48 is adjustably attached in a rigid manner to the marginal end portion of the stand pipe and aligned within close proximity to an encapsulated reed switch 50 with the reed switch preferably being atjp tached to the inside peripheral wall surface 42. Wires 52 are "electrically connected to the reed switch. Adapter 54 enables the reed switch to be readily removed from the stand pipe housing, while cap 56'protects the upper extremity of the device from environmental elements.
In operation the flow device can be used in a number of different applications, as for example to actuate a solenoid actuated control valve; however, it is preferred to explain the details of the operation in conjunction 'with a downhole pump wherein the downhole pump has a controller which cyclically actuates an electric motor which in turn provides the power to drive the downhole pump. The switch of the instant invention is preferably connected to the motor controller in a .manner whereby after the pump motor has been started by the con- 7 -troller, and after a suitable time delay in order to permit the movable element of the flow, no-flow device to assume the open position, subsequent actuation of the reed switch to the open position will interrupt current flow and accordingly discontinue, operation of the pump motor.
ltzshould be understood that other switching arrangements than as shown and described herein are contemplated. For example, a pneumatically controlled circuitry device can be sub- .stituted'for the magnet and reed switch and such a modification is considered to still fall within the comprehensionof the present invention. Furthermore, incorporation of the various mechanical linkages which actuate switches, such as a mercury switch or a mechanical switch, is also considered to be within the comprehension of this invention.
In operation, andassuming the timer to have started fluid flow from. theproduction zone of an oil well, gas will initially sidered in conjunction with the weight of the various elements attached to the diaphragm must be of a ratio to provide a resultant force which moves the 'movable element in an upward direction prior to liquid overflowing through ports 40. As the hydrostatic head causes the movable element to open, the main flow path will occur through the seat provided'by the orifice and hence through outlet 14. This action enables the stand pipe to telescopirigly receive the switch housing, thereby aligning the magnet with the reed switch, whereupon the contact points of the reed switch are magnetically attracted by the magnet and caused to assume the closed position. This action must occur before the timed delay period of the motor controller runs out. The reed switch is now in control of the pump and should its contact points open due to cessation of liquid flow, the current flow to the pump motor will be interrupted to thereby maintain the pump in standby condition until the next timed cycle of the controller.
Assuming the reservoir associated with the borehole should :reach a-pump-off condition, gas will flow into inlet 12 where it enters port 36, where the gas will'then rise within the stand pipe, travel through ports 40, continue back through the passageway 44, and then flow through chamber 25 and outlet 14. This action eliminates the hydrostatic head previously present within the stand pipe and accordingly the resultant forces exerted against each side of the diaphragm is changed sufficiently to cause the valve element to move in the downward direction. This action moves the magnet away from the reed switch, causing the contacts of the reed switch to assume the opened position which in turn deenergizes the pump LII motor. The control device is now"-in the standby condition .awaiting the next timed cycle of operation whiph will be carand gaseous flow through a flow conduit; a flow,. no-flow device adapted to be flow connected in fluidflowrelations hip with respect to the flow conduit, comprising.
said flow, no-flow device including me nsf orminga main housing .having an inlet. an outlet. ojriticefa movable element, and an equalizer conduit; said movable element and said orifice being disposed within said main-housing and cooperating together to form an inlet chamber. an outlet chamber, and an upper chamber, with said orifice being interposed betweensaid inlet chamber and saidoutlet chamber, and with said movable element being interposed between said upper chamber and said inlet chamber; i
said inlet being connected to said inlet chamber, said outlet being connected to said outlet chamber;
means associated with said movable element for enabling said movable element to be moved from a position adjacent said orifice to a position spaced-apart from said orifice; 1
said equalizer conduit being affixed to said movable elementand having at least a portion thereof located in said upper chamber; said equalizer conduit having flow passageway means for forming a passageway from said inlet chamber; through'said'movable element, and into said upper chamber, said flowpassageway means of said equalizer conduit adaptedto'form a hydrostatic head therein when a sufficient quantity of liquid flows into said inlet chamber;
means forminga flow passageway from said upper chamber, through said movable element, and to said outlet chamber for flow communicating said upper and outlet chambers togetherwhen said movable element is adjacent the orifice;and
control means connected to be actuated-by said movable element for discriminating between liquid and gaseous .flowthrough the device.
2. The improvement of claim l-wherein said equalizer conduit is a vertically disposed stand pipe having a lower end p'ortion rigidly affixed to said movable element, and with'the lower extremity thereof being flow connected to the outlet chamber; and with the upper extremity of saidstand pipe being flow connected to the upper chamber of themain hous- 3. The improvement of claim 2 wherein said control means includes: I
a magnet attached to and adapted to move in conjunction with said movable element; and
a magnetically actuated switch adapted to be actuated by said magnet; whereby when said magnet is brought into close proximity of said switch, the switch is actuated to thereby providethe recited function of indicating the presence of liquid fluid flow.
4. The improvement of claim l wherein said control means includes:
a magnet'attached to and adapted to move in conjunction with said movable element; and
a magneticallyactuated switch adapted to be actuated by said magnet; whereby whensaid' magnet-is brought into close proximity of said switch, the switch is actuated to thereby provide the recited function of indicating the presence of liquid fluid flow.
5. The improvement of claim 3 wherein said fluid conduit includes the production-tubing of an oil well, and further including an oil well production pump located within the well, an electric motor for actuating said pump, means forming a controller for said motor. said controller cyclically energizing said motor, means by which said switch is attached to said controller to deenergize said motor upon the well assuming a pump-off condition.
6. The improvement of claim 1 wherein said control means includes:
a magnet attached to and adapted to move in conjunction with said movable element;
a magnetically actuated switch adapted to be actuated by said magnet; whereby when said magnet is brought into close proximity of said switch, the switch is actuated to thereby provide the recited function of indicating the presence of liquid fluid flow; and
said fluid conduit includes the production tubing of an oil well, and further including an oil well production pump located within the well, an electric motor for actuating said pump, means for forming a controller for said motor, said controller cyclically energizing said motor, means by which said switch is attached to said controller to deenergize said motor upon the well assuming a pump-off condition.
7. The device claimed in claim 8 wherein said movable element includes a flexible diaphragm having the circumferentially extending edge portions thereof affixed to said main housing; said movable element having means forming a face thereon;
said orifice having an upwardly depending edge portion which forms an entrance thereinto, and which engages said face of said movable element whensaid movable element is moved into engagement with said orifice; and
said means forming a flow passageway. from said upper chamber to said outlet chamber being in the form of vertically disposed passageways formed through said face and spaced-apart from said equalizer conduit, whereby gas flows from said inlet chamber, through said movable element, through said equalizer conduit, into said upper chamber, through said vertically disposed passageways,
into said orifice, and into said outlet chamber.
8. The device of claim 7 wherein said equalizer conduit is in the form of a standpipe; said stand pipe depending from said movable element in a direction opposite from said face; whereby: liquid flows into said inlet chamber, through said movable element, and into said stand pipe to thereby provide a hydrostatic head within the stand pipe which causes said face to lift free of said orifice, whereupon the movable element is moved to the recited position spaced-apart from said orifice, and thereby permits liquid flow to occur from said inlet to said outlet.
9. The device of claim 1 wherein said orifice is in the form of a wall having an aperture therein, said movable element is in the form of a diaphragm having a plug thereon; said plug adapted to be seated against said orifice to thereby divert gaseous fluid flow from said inlet to said upper chamber and thence to said outlet chamber, and to permit liquid fluid to flow directly from a said inlet chamber to said outlet chamber when said plug is lifted from said orifice 10. The improvement of claim 8 wherein said equalizer conduit includes a standpipe rigidly affixed to said movable member and having a lower end portion thereof flow connected to the inlet chamber by means of drilled passageway located in said movable element, said stand pipe having means forming an overflow with said overflow being spaced-apart from said drilled passageway which enables the recited hydrostatic head to be effected within the stand pipe when liquid flows into said inlet chamber, and which enables gas to flow from said inlet chamber, through said stand pipe, into said upper chamber, through said means forming a flow passageway, through said orifice, and into said outlet chamben