US2347779A - Well apparatus - Google Patents

Description

w. A. HEATH WELL APPARATUS Filed April 7, 1942 May 2, 1944.

Patented May 2, 1944 v WELL APPARATUS Willis A. Heath, Baxjlesville,

Phillips Petroleumv Company,

Delaware kla.. assigner to a corporation of Application April 7, 194.2, serial No. 438,035

4 claims. (el. 137-34) This invention relates to well apparatus adapted to be employed in the secondary recoveryof hydrocarbons, and more particularly to apparatus for controlling the flow of fluid from an upper uuid-bearing formation into a lower hydrocarbon-bearing formation through a well bore that communicates with both forniations.

It has generally been the practicel heretofore, in the recovery of hydrocarbons from underground formations by water flooding, to obtain the water that is transmitted into the hydrocarbon-bearing formation from either a surface or a subsurface source of supply. Whether the water is derived from a surface source of supply, such. as a lake or stream, .or from a subsurface source of supply, such as a water well, it 1s essential that suitable pumping equipment and pipe lines be provided to convey the water from the source to one or more input Wells. Upon arrival at an input well the water is metered and injected therethrough under predetermined pressure. The volume and pressure of the water so introduced into the, hydrocarbonbearing formation depends on various formation characteristics which are ascertained from a complete study of the formation including analyses of core samples of the material of the formation.

In many oil pools, water-bearing formations are existent above a hydrocarbon-oil-bearing formation. Water from the upper formation may be utilized -in waterflooding the hydrocarbon formation through a common well bore u provided` that the volume and pressure of the water is properly controlled. By employing this water it will be evident that the expense of obtaining and handling necessary water from extraneous sources can often be eliminated.

Regardless of whence the water is obtained for use in secondary recovery operations, it is important to exercise control over the pressures and volumes of the water that is injected into the hydrocarbon-bearing formation in order to effect maximum oilv recovery at a minimum cost and to recover the oil within a reasonable time after operations are commenced. It is a relatively simple matter to flood a formation of uniform permeability, i. e.; one in which the resistance .to flow of fluid is substantially the same throughout. Unfortunately, such is rarely the case, as the permeability of individual oil kreservoirs varies widely and uids urged therethrough flow along the path of least resistance which is through the more permeable regions. Care must therefore be taken to move the oil content through the formation in a body. If the quantity and pressure of the water that is injected into the formation is excessive, it will break through or by-pass the oil bank and flow toward the output well with the result that only small portions of oil, if any, will be recovered per unit time. On the other hand, should only small amounts of water be injected into the formation, it may be months or even years before any appreciable quantity of oil is recovered. From the foregoing, it will be evident that small volumes of injected water at low pressure or large volumes at excessive pressure are each undesirable from an economic point of view. It is therefore essential that the fluid driving medium, generally water, must be introduced into the formation in proper quantities and under lproper pressures.

' the lregion of the water bearing formation. The

well casing is packed off at a point intermediate the formations and a conduit extends through the packing. Said conduit includes a lower portion which is relatively stationary in the well bore and an upper portion that is telescopically.

disposed with respect to the lower portion. A plurality of spaced passages in the lower portion of the conduit may be placed invor out of communication with an annular space formed between the conduit and the casing by raising or lowering the upper portion of the conduit.

As will be apparent from the detailed description set forth further along, the injection of water into the hydrocarbon-bearing formation is at all times under the control of the operator.

This-invention therefore has vfor its principal object the provision of apparatus for transmitting controlled quantities of fluid from an upper fluid-bearing formation into a lower fluid-bearing formation through a common well bore to drive the 4fluid in the lower formationtoward a region whence it is withdrawn to the surface of the ground.

`It is another object of this invention to provide apparatus for effectively and economically flooding an underground reservoir.

A further object pf this invention is to provide apparatus of the character indicated, which apparatus is sturdy and simple in construction and'comparatively inexpensive to manufacture,

install and operate.

'I'hese and other objects and advantagesI will be apparent to persons skilled in theart by reference to the following description and annexed drawing which respectively describe and illussection.

Referring to the drawing, and more particularly to Figure 1 thereof, I have denoted a well `bore I that extends through a water-bearing formation II and that .penetrates a hydrocarbon oil-bearing formation I2. A string of well casing I3 extends downwardly through the well bore and is provided with a plurality of perforations I4 in the region of water formation II to permit the entrance of water thereinto. A string of tubing I5 is disposed within casing I3 and spaced therefrom to form an annular passage I6. Tubing string I5 is coupled to a control apparatus, generally indicated by reference numeral l1; communicates with aconduit I8 that extendsv through a conventional packer I9, such as a hook wall type of packer; and terminates in a tail pipe 20. It will be noted that by virtue of the arrangement illustrated in Figure 1, packer I9, when in operative position, prevents water admitted into annular passes I8 from flowing therethrough into the lower formation; but permits fluid introduced into tubing string I5 to pass directly into said lower formation.

Let usturn next to Figure 2 for details of con- 4g 28 is maintained in the illustrated position by means of a follower sleeve 21 that is in threaded engagement with the lower extremity of swaged body 2|.. Gasket 28F forms an adequate seal to prevent the leakage of fluid between body 2| and the outer surface of conduit Il. A 'series of vertically spaced ducts 28 is provided in yconduit I8 to establish communication between the interior of the conduit and annularpassa'ge I6 under conditions which will be explained in the discussion of the operation of the invention. A body 29 embraces conduit rI8 and supports a ring .30 that is composed of rubber or a similar material and that is'adapted to form a seat to receive end face 3| of sleeve 21.

In the practice of my instant invention, the Y apparatus is assembled and lowered into a well bore until it assumes the position illustrated in Figure 1 with packer I 8 expanded to bridge annular passage I8 and support conduit I8 and the equipment therebelow in a 'substantially fixed POSition. It will be noted that with the apparatus disposed in this manner, packer I9 is; located at a level intermediate perforations I! in be noted further that swaged body I1 has been lowered with respect to conduit I8 until sleeve 21 engages ring 30 to lform an effective fluid seal therewith. Water enters casing I3 from 5 water-bearing formation II by way. of perforations I4.

Tubing I5 is raised a. suiiicient distance to unseat follower sleeve 21 from ring 30 and to establish communication between lowermost duct 1o 28 and annular passage I6 whereupon water in the annular passage flows through said duct and downwardly into oil formation I2. The head of water in the tubing string and the rate of iiow of the water into formation I2 may be readily 15 determinedV in any manner well known in the art. The rate of ow and the pressure of the water thus transmitted from water formation II into oil formation I2y is determined for various relative positions of body 2| and conduit I 8. It will be obvious that the greater the number of ducts 28 that'are placed in direct communication with annular passage I8, the greater will be the quantity of l water and hence the pressure of the column of water in the apparatus. For example, when tubing I5 and body 2| is raised to the position illustrated in Figure 2, it will be seen that the three lowermost ducts 28 communicate directly with annular passage I6, thereby allowing more water to enter conduit I8 than if only the lowermost or the two lowermost ducts communicated directly with passage I6. By the same token,cor-

respondingly greater quantities of water will owl into conduit i8 when the tubing string is raised so as to expose additional ducts.

Having previously studied the characteristics of oil-bearing formation i2 and having ascertained the quantity and pressure of th water necessary to obtain. optimum results in the secondary recovery operations, tubing i 5 is raised until the requisite number of ducts 28 are placed in direct commission oi7 water into the tubing string may be varied at will by adjusting the relative position of body 2| and member 29. When itis desired to terminate iiow into conduit I, tubing I5 is lowered until gasket 26 seals conduit I8 below the lowermost duct, or preferably until follower sleeve 21 .is firmly seated on ring 30. To remove the apparatus from well bore, tubing I5 is raised until grooves 25 in body 2| engage ribs 24. The

tubing is then turned about a vertical axis, thereby turning conduit I8 and disengaging packer I9 from the interior wall of the well casing. With the packer thus freed, the entire-mechanism is withdrawn from the well bore in the usual manner.

From the foregoing, it is believed that the operation and advantages of the apparatus for practicing my instant invention will be readily coinprehended by persons skilled in the art. It is to be clearly understood, however, that various changes in Athe apparatus shown and described may be resorted to without departing from the Y spirit or the invention, as defined by the appended claims.

outerconduit to forman annular passage therewith, one of the conduits being longitudinally movable with respectto the other conduit. means comp g a flexible member carried by one of the conduits for forming a uid seal across the casing I3 and oil-bearing formation I2. It will 75 annular passage,acombined stop and valve memmunication with annular passage- S. The trans- 2,347,779 ber carried by the inner conduit for limiting 1ongitudinal movement of the movable conduit with respect tb the other conduit in one direction and for cooperating with one end of the outer co'nduit to form a fluid seal between the annular passage and the exterior of the outer conduit, means for effecting coupling engagement between the conduits upon predetermined longitudinal movement of the movable conduit inthe opposite l direction to limit relative movement of the movable conduit with respect to the other conduit in said opposite direction and to prevent relative rotational movement of either conduit with respect to the other conduit while permitting relative longitudinal movement of the movable conduit with respect to the other conduit in the rst mentioned direction, and a plurality of longitudinally spaced ports in the inner conduit, one oi said ports establishing communication between the interior of the inner conduit and the exterior of the outer Conduit upon predetermined longitudinal movement of the movable conduit in one direction, additional ports coacting with the flexible member and establishing communication between the interior of the inner conduit and the exterior of the outer conduit upon further predetermined longitudinal movement of the wherein the second mentioned means comprises at least one projection extending beyond the outer surface or the inner conduit and at least one groove formed in the inner surface of the outer conduit to receive said projection.

4. In apparatus of the character described, the combination comprising an inner conduit, an outer conduit surrounding a portion of the inner conduit and spaced therefrom to form an annular` passage therewith, said outer conduit being movable longitudinally with respect to the inner conduit, a flexible member secured to and movable with the outer conduit and disposed intermediate the extreme ends of the outer conduit to form a fluid seal across the annular passage, a combined stop and valve member carried by the inner conduit for limiting longitudinal movement of the outer conduit with respect to the inner conduit in one directionuand for cooperating with one end of the outer conduit to form a fluid seal between the annular passage and the exterior of the outer conduit, means for effecting coupling engagement between the conduits upon prederespect to the other conduit While permitting re1- ative longitudinal movement of the outer conduit with respect to the inner conduit in the nrst mentioned direction, said means including at least one projection extending beyond the outer surface of the inner conduit and at least one vand the exterior of the outer conduit upon predetermined longitudinal movement or the outer conduit in one direction, additional ports establishing communication between the interior of the inner conduit and the exterior of the outer conduit upon further predetermined movement of the outer conduit in the same direction.

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