US2844206A - Oil and gas flow control device - Google Patents

Description

July 22, 1958 E. A. RODGERS OIL AND GAS FLOW CONTROL DEVICE Filed Sept. 22, 1954 INVENTOR. ELBERT A.RODGERS g ,40 O Y k '6 3 HIS eenri United States PatentO OIL AND GASFLOW-CONTROL DEVICE Elbert AlfordtRodgers, Altus, Okla. Application September 22,1954, Serial No. 457,714

:8 Claims. ,(Cl. 166--54) This invention relates to an apparatus for controlling the flow of oil and gas from producing wells.

The present device allows oil to be flowed from the earth formation in a well regulated manner so as'to maintain the reservoir pressure of gas, and at the same time, maintain a pressure control sothat the-encroachmentof the Water will drive the oil to the proper level, thereby giving greater recovery-of oil withthe minimum loss of reservoir gas pressure and with theproduction of a minimum of water.

An object of this invent-ionis to provide means for controlling the fluid levels, the-liquid flow iand the gaspressure Within anoilwell.

Another object ofthe invention is to provide an oil and gas separator which willautomatically maintain the gas within the producing formation, and at the same time, permit the flow of'oil from'the formation in a regulated manner as the oil isproduced.

Still another object of the invention is to provide a float controlled device to prevent-the-escape of gas fromthe producing formation.

A-still further'object of this invention is'to provide a liquid level control within a'well, wherein dual valves control the outflow of liquid from the producing horizon.

A yet-further objectof the invention is toprovide' a float for a flow and pressure control devicewherein the float is pressure equalized.

"-Yet another object of the'inventionis to-provide'a'separator at the bottom of a well'which 'separator'conserves bottom hole pressure.

Another object of the inventionisto 'provide'an {oil and gas separator and flow and liquid control device that is simple in construction, positive in operation, and which requires little attention during operation.

With these objects inmind, and others that will manifest themselves 'asthe description'proceeds,"reference is to be had to the accompanying drawings in which like reference characters designate like parts in the several views-thereofl in which: I

Fig. 1 is a longitudinal, vertical sectional view 'throug'h an oil well, with parts broken away and shortened, and withiparts shown in-elevation tobring out the details of construction; i

Fig. '2 is an enlarged longitudinal sectional view with parts broken away and shortened, and with parts shown in elevation of the apparatusfor controlling the respective levels-of the oil, gas and'water and for controlling the flow andpressure of oil and gas within a well, and showing thefloat in raised position;

Fig.3 is atransverse' cross sectional viewtaken on the line 33 of Fig.2, looking inthe direction indicated'by With more specific reference to the drawing, the numerall designates a "bore hole of a' well having the usual "ice casing 2'therein,with the conventional casing head 4 positioned thereon toiform a seal between casing 2 and tubing 6therein. A gas pipe 8 leads from the casing head 4, which gas'pipehas a'valve 10 therein which forms a closure therefor. "Thetubin'g 6'has the usual coupling 12 thereon, which coupling connects with the proper flow linesto direct the oil to the desired point of use. I

An'oil and gas separator andflow and liquid level control device,'desi"gnated generally at 14, is positioned on the'lower end'of tubing *6, which device has a perforated pipe extension '16 extending from the lower end thereof to a;pointwithin-the producing formation 18 so ,that oil maybe admitted'throu'gh perforations 20 of the pipe extension 16 above the waterlevel '22 and below the oil-gas level24.

With-theperforations20 thus arranged within the oil zone, and with th'e-float'26 within the separator and the flow control regulated so that oil will flow into the separator to' a regulated degree, oil may be pumped .or flowed from the separator 14 up through tubing 6 to be discharged out through coupling 12 to a point of use.

The float' 26 is-of such buoyancy so as tocause it to open andclosea valve to "permitthe flow of oil through the separator 14.

The oiland-gas separatorand liquid level flow control device has a cylindrical casing 28 which is closed .at its upper end by means of ahead "or swaged capmember 30. The cylindrical casing'28 forms an enlarged float housing or chamber 28a to 'encase the float 26. This enlarged housing or chamber makes possible the use of a larger cylindrical tubing 28 to house the float 26, the threaded ends -34 and 36 "of swaged cap member 30 and swaged nipple 32 being reduced so as to threadably engage .the respective conventional'collars 38 and 40 which interconnect respectivelywith tubing'6 and perforated pipe extension 16 with the'upperand'lowerendsthereof respectively.

A pipe 42 threadably-engages thehea-d 30 and connects with the 'axial'opening 44 withinthe head '30. The pipe "42 projects downward and has a closed lower end. Perforations 46-are formedwithin'the pipe extension 42 near the lower end thereof and below a seat 48 on'pipe extension 42.

An annular float 26 comprises an outer concentric sleeve 26a andan innerconcentric sleeve 26b, which sleeve 26b is telescoped into sleeve 26a so as to form an annular c'ham'ber'26c, which chamber is closed at the top thereof byan annular'ring 26d whichis secured in fluidtig'ht relationtbetween .sleeves' 26a and 26b. 'The lower end-.of the chamber 260. is closed'by an annular ring 126.2 which is secured'between sleeves'26a and 26b in fluid tight relation. Thering "26epreferab1y has atapered valve seat 56011 the bottom thereof. Thefloat 26 is.of such length as'to'have=suflicient'buoyancy in the particular depth well that is .being flowed. The inner sleeve 26b has an annularring 26f'formed therearound a spaced distance upwar'd from thelower end thereof. A valve seat 50 is formed on the lowerface of the annular ring 26 soas to complementarily engage valve seat 48, as willbe'brought out more in detail hereinafter. The float 26 is sleeved over downwardly extendingpipe extension 42 and has'an annular seat :50 th'ereinfor complementary seating upon a seat '48 when the float '26..is in its lower-mostposition.

A .set collar52 is secured .to the downwardly extending pipelextension 42.to limit'the height to which the float126 may rise. The outer sleeve 26a of the float26 has per-' is adapted to complementarily engage a tapered valveseating face 58 on the upper face of a plug 60 which plug is secured within the lower end of the cylindrical casing 28. The plug 60 has an axial recess 62 formed therein to receive the lower end of downwardly extending pipe extension 42 so that the perforations 46 will be substantially adjacent the valve face 58 on the plug 60. The plug 60 has a series of circumferentially spaced, longitudinal, non-axial openings 64 therethrough, which connect the float chamber 66 with the perforated pipe extension 16 which leads to'the formation reservoir. The plug 60 has a recess around the outer top side thereof, so that fluid passing upward through passages 64 will pass into chamber 66, when the valves 56 and 56 are seated. This enables liquid passing into chamber 66 to fill the chamber to a sufficient height to cause the float 26 to raise, whereupon the liquid will flow outward from chamber 66 through perforations 46 into pipe 42. The float 26 will remain raised so long as there is suflicient liquid Within the chamber to buoy up the float and to keep the valves 59 and 56 above their respective seats 48 and 58. In this manner the out flow of liquid from chamber 66 is regulated without permitting gas to escape, as the float is buoyed up by liquid only.

The small perforation 68 is provided near the upper end of cylindrical casing 23 so as to admit gas under pressure into cylindrical casing 28 so as to enable the float 26 to function properly, as will be more fully explained hereinafter.

It is to be pointed out that the distance from the annular valve face 48 to the valve seating face 58 is the same as the distance from the annular valve seating face 50 to valve seating face 56, so when the valves seat the pipe extension 42.will be sealed against entrance of fluid thereinto from chamber 66 when the float 26 is in its lowermost position.

If oil or water is pumped or flowed from the well faster than the formation will produce, the liquid level will drop, thereby lowering the float, and causing the- valves 50 and 56 to seat on seats 48 and 58, respectively, so as to restrict or choke the flow of oil into and out through pipe 44, thereby preventing the gas from escaping, which gas will remain trapped above the oil-gas level 24 in casing 2.

Operation The oil and gas flow device is installed within a producing well in a manner as described above, and as shown in Fig. 1. Oil, gas, and water are the usual components within a producing well, each of which fluids seek their respective level, when conditions become static. The water level is indicated at 22 and the oil level at 24, in Fig. l, with the zone thereabove being filled with gas, which gas is maintained under pressure by closing stop cock on pipe 8, which pipe leads from the casing head 4 to a point where the gas may be used, if desired.

The float 26 is of such buoyancy as to float within the liquid, which is usually oil, so as to permit the oil to flow upward through pipe 16 into and through gauged orifices 64 within plug 60. The oil which flows through these orifices into chamber 28a will enable the float to be buoyed up until the upward movement thereof is arrested by a set collar 52 secured near the upper end of pipe extension 42. The upward movement of the float 26 will cause the lifting of the valve faces 50 and 56 from valve seats 48 and 58, respectively. This will permit the liquid to flow from chamber 28a through perforations 46 into and 56 seat on the respective valve seats 48 and 58 so as to prevent the escape of gas therethrough. With the lindrical casing 28, the float 26 will seat to prevent gas from flowing upward through downwardly extending pipe extension 42 which pipe extends downward into chamber 23a from the head or cap member 30, so as to direct liquid upward therethrough into passage 44 connected with tubing 6. The plug 60 may be threaded into the lower end of cylindrical casing 28 and may be readily removed therefrom to be replaced by other plugs, the orifices of which vary in size. The size of the orifices 64 in the plugs 60 gauge the amount of oil, produced from the formation, in such manner that the oil may be produced without producing water therefrom, and with the float arrangement as hereinbefore set out, which utilizes dual valve seats 48*50 and 56-58 to seat in such manner as to seal the passage 44 from chamber 66, it will be readily appreciated that the gas may be maintained within the reservoir so as to force the level 24 of the oil downward by gas pressure and permit the level of 22 of the water to rise upward until the gas surface and the water surface meet, at which time the maximum productivityof the oil bearing strata has been reached. By accomplishing this in a Well regulated manner, that is, over a period to permit the oil to be thoroughly flowed from the formation, it will be seen that the ultimate recovery from the strata may be increased many fold, over the conventional methods used, wherein the oil, gas and water are taken off by rapid flow and without the separation of the oil from the gas and water at the bottom of the hole.

By producing oil and gas in this manner, the rapid expansion of the gas is minimized. Rapid expansion of the gas causes the chilling thereof, which chilling acts on the formation causing paraflin and/ or wax to congeal, thereby retarding the flow of oil from the formation. With the arrangement as herein set forth, such rapid expansion of the gas does not take place.

With the present method of producing oil, a greater percentage of oil and a lower percentage of gas is proi: duced, thereby enabling the gas to be maintained within the reservoir for future use, after the ultimate future recovery of oil has ceased.

While the device has been described and illustrated in some detail in one embodiment thereof it is to be understood that changes may be made in the minor details of construction, and adaptations made for different installations, without departing from the spirit of the invention or the scope of the appended claims.

Having thus clearly shown and described the invention, what is claimed as new and desired to secure by Letters Patent is:

1. An oil and gas flow control device for a string of tubing suspended in a well, comprising a hollow cylindrical casing secured at its upper end to the string of tubing, a hollow head closing the upper end of the casing,

a gas vent located in the casing below said head, a pipe disposed centrally within the casing and extending axially 2 being movable axially along the pipe in response to variations in liquid level within the casing, a first annular valve formed on the lower end of the float, a first annular valve seat formed on the plug inwardly spaced from the plurality of passages therein for cooperation with said first valve when the float is resting in its lowermost position on said first seat, a second annular valve seat formed on said pipe above the inlet opening therein, and a second valve mounted on the float for engagement with said second valve seat simultaneously with the seating of the first valve on the first valve seat, whereby said valves prevent fluid from flowing from the casing into the pipe when the float is resting in its lowermost position.

2. The invention defined by claim 1 in which the float comprises a pair of concentrically spaced inner and outer tubular sleeves forming an annular buoyant chamber therebetween, said chamber being closed at the top and the bottom thereof by a pair of upper and lower rings fitted between said sleeves, said lower ring having the first annular valve formed on the bottom thereof, and said "inner tubular sleeve having the second annular valve mounted thereon.

3. The invention defined by claim 1 in which the plurality of non-axial passages extending longitudinally through the plug are gauged orifices spaced circumferentially and disposed concentrically around the exterior of the annular valve seat formed on the plug.

4. The invention defined by claim 1 in which the plug is removably secured to the lower end of the casing and is adjustable longitudinally thereof.

5. The invention defined by claim 1 in which the plug is provided with a recess open to the interior of the casing for projection thereinto of the pipe which is disposed centrally within the casing, and the inlet opening in said pipe is located directly adjacent to the inner ends of the passages extending through the plug.

6. The invention defined by claim 1 in which the valve seat formed on said plug is beveled inwardly and downwardly, and said valve face formed on the lower end of the float is beveled inwardly and downwardly to engage said valve seat in complementary relation.

7. The invention defined by claim 1 in which the centrally disposed pipe is mounted interiorly of the annular valve seat formed on the plug, said pipe having the lower end thereof closed, and wherein at least one opening of predetermined size is formed laterally through the wall of the pipe near the lower end thereof.

8. The invention defined by claim 1 in which the float comprises a pair of concentrically spaced inner and outer tubular sleeves forming an annular buoyant chamber therebetween, said chamber being closed at the top thereof by a ring fitted between said sleeves, and wherein at least one aperture is formed in the outer sleeve near the lower end thereof to provide communication between said buoyant chamber and the interior of the cylindrical casing.

References Cited in the file of this patent UNITED STATES PATENTS 2,128,475 Rodgers Aug. 30, 1938 2,142,376 Rodgers June 3, 1939 2,322,453 Kaveler June 22, 1943

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