US2098484A - Packer - Google Patents

Description

Nov. 9, 1937.

w. J. BR'UNDRr-:D Er A. 2,098,484

PACKER Filed April 21, 1956 2 sheets-sheet 1 n n 4 a f l n r f r a n r d r r f r n I! n r n a n a n r A n n r r d n r l n n 4 d n n r f n r i f r n a n v l r r a n r r 4 n f4 l r r n l n r n a r n f r r n n n n n n n n n n f n r n n a f n A 1 www@ ENTORS ATTORNEY.

Novf 9, 1937. w. J. BRUNDRED ET A1.A 2,098,484'

PACKER Filed April 2l, 1956 2 Sheets-Sheet 2 i ai? Patented Nov. 9, 1937 PATENT OFFICE PACKED William J. Brundred, William E. Crowley, and Robert B. Bossier, Oil City, Pa., as'sixnors to Brundred Oil Corporation,` il poration of Pennsylvania City, Pa., a cor- Application April 21, 1936, Serial No. 75,574

7 Claims.

The principal object of this invention is the provision of a packer that is capable of being posi-4 tioned at any desired depth within a well to seal off one stratum from another withoutlimiting the number of packers that may be employed in the same well.

Another object of this invention is the provision of a packer that does not depend upon the movement or mechanical operation of a string of tubing to expand it into sealing engagement with the bore ofl the Well.

will contract axially as it is expanded radially, to

compensate for the displacement due to the distor'ticn thereof, thereby minimizing the stretchularities in the walls of a well.

Other objects and advantages will appear hereinafter.

In the accompanying drawings wherein a prac# tical embodiment of the principles of the invention is illustrated:

Fig. 1 is a vertical section of the packer mounted on a. well tubing and shown deated.

Fig. 2 is a view similar to Fig. 1 showing the packer inated and not conned.

Fig. 3 is a view similar toFig. 1 showing the packer inated within a well.

Fig. 4 is a view similar to Fig. 1 showing a modiiication of this invention.

Referring to Figs. 1 to 3 of the drawings, I represents the packer stem which comprises a section of tubing having the threaded ends 2 and 3 for connection with the consecutive lengths of well tubing or coupling members 4 and 5 to form a string. yIhe Stem I is preferably made of tubing having the same internal diameter'as the well tubing to permit the passage of a plurality of smaller pipes therethrough. These smaller pipes may or may not be arranged concentrically within the tubing string.

Intermediate of its ends the stem I. is provided with one or more nipples 6 which extend Another object is the provision of a packer that ing strains in the packer when it is sealing irreg' (Cl. 16S-10) at 1. 'Ihese nipples communicate with ports in the stem.

8 represents cap members on each end of the stem I which are arranged to enclose and protect the ends of the packer. Each cap member has a cylindrical neck portions which extends from an enlarged cylindrical portion I0. The opposite lace of the cylindrical portion In is hollowed out to provide thecup II, preferably having a dat bottom I2 and the outwardly flaring sides Il. j-

The perimetral surface of the neck 9 has formed thereon the annular notches I4 which may be engaged by a shing tool or the like to withdraw the packer assembly from the well.

'I'he cap members 8 are provided with the concentric bores I5 arranged to receive the sleeves IE which may be detachably connected thereto as by the set screws Il. It should be noted that the sleeves I8 extend into the cups II as shown in the lower cap 8 of Fig. 1. 'I'he sleeves I6 are withdrawn after the, packer has been formed thereon and are replaced by the shorter sleeves I8 which are secured by the 'set screws I`I, as shown in the upper cap 8 of Fig. 1, thereby forming the pocket Il ln each end of the packer.

20 represents the packer which is preferably made of resilient material, such as rubber. The packer is molded on the stem I, around the nipples 8 and between the caps 8, so that the material when vulcanized will adhere to the adjacent metal parts. The inner ends of the sleeves I6 may be covered or otherwise protected so that they will not adhere to the rubber and may be easily withdrawn therefrom and replaced by the 'shorter sleeves I8 to form the pockets I9.l Thus the packer assembly comprises a unitary mem'- ber made up of the resilient material, the stem and the cap members. v

In forming the packer, first an inner or foundation wall 2l is formed 'about the stem and then a layer of material, such as kraft paper, which will not bond with the rubber, is placed around such wall, stopping short however of the cups I I of the caps 8, and then additional rubber is added to complete the packer. This non-bonding material extends over the outer ends of vthe nipples 6 to 23 represents annularreenforcing members which may be embedded in the rubber in spaced relation from the ends of the inflation chamber to prevent the material of the packer from tearing.

. encased in the cups, Il of the cap members 8.

24 represents reenforcing means, such as fabric embedded in the rubber of the packer', which does not hinder the flexingy characteristics of the packer. This reenforcing means encases the inflation chamber 22 and is spaced therefrom. It

y is desirable to extend these layers of reenforcing material into the cups Il of the cap member 8 in order to strengthen the rubber at the points where the inflation thereof creates the greatest change between the portions that are stretched and the portions that are more or less ilxed. The reenforcing material may be so wrapped or otherwise applied that the Aends taper off and are in spaced relation to the bottom and sides of the cup II. j

The perimetral surface of the packer is formed over the reenforcing material 24, thereby providing a uniform Wall of rubber on each side thereof. It may be desirable to provide an expansible sleeve (not shown) on the perimetral Surface of the packer to protect the rubber. However, it has been found preferable to use a new synthetic compound known as Duprene or Thiokol which is not subject to deterioration when in contact with oil.

When assembling the packer in a well the lower end of the stem l is provided with the loosely fitting collar 25 and then screwed into a pipe s'ection or joint member 5. Then -a similar collar 25 is placed around the stem on top of the packer and the next consecutive'pipe section or joint member 5 is screwed in place.

Referring to Fig. 2 wherein the packer is inated, without restriction, by a fluidl medium under pressure within the stem I, it will be noted thatthe cap members 8 have been drawn inwardly toward the center of. the packer. The cap members are free to move longitudinally on the stem and are permitted to slide inwardly to comi pensate f or the lateral expansion of the rubber. 'Ihe packer material comprising the wall 2| and the ends within the cups i I is under compression and ows into the annular pockets I9 provided for that purpose.

. panded by inflationy to seal the wall of a well which is considerably larger in diameter than the packer itself.

However in practice it is preferable to design the packer small enough to clear irregularities of the well to be packed. The packer will then have a longer contacting surface with the portion of the wall to be sealed and repeated expansion and contraction will not materially affect the life thereof. Thus Fig. 3 shows a preferred application of a packer within a well wherein a small expansion of the packer issuillcient to seal one stratum from another. In this instance the annular pockets I 9 are only partially lled by the flow of the resilient material that is under compression.

It has been found that when the packer is only partially inflated it has 'a tendency to become elongated. The collars 25 then serve as stops for limiting the longitudinal movement of the cap members 9 on the stem. Upon further inflationv drawing the cap members 9 toward the center of the packer.

Thus the packer may be ex- Referring to Fig. 4 which represents a modification of the packer, 26 represents a section of the perimetral surface on each end of the stem I that is covered with a material that will prevent the rubber from vulcanizing thereto. These sections function in the same manner as the pockets I9 and thereby eliminate the use of the sleeves I6 and I8. This construction of packer has been -found to work satisfactorily for packers that are not required to expand to an excessive diameter to function as a seal. Sufficient space is provided in these small pockets to permit the material to flow thereinfwhen the packer is inilated.

The packer may also be used to seal a casing as well asthe bare'hole of a Well and it is particularly advantageous for practical use in that it provides a clear path in the string of tubing of which the stem forms a section. Again the packer is not subjected to any mechanical stress other than the inflation thereof.

With this design of-v packer any number may be placedon a single string of tubing and all of them may be simultaneously inflated from a singlesource 'of fluid pressure or they may be segregated by placing them on concentric strings of tubing to seal one string from another.

It is to be noted that inasmuch as the ends of the packer are capable of movement, the inflation of the packer is not attended by such stresses as would be effective if its ends were held against movement. In the latter case the material of the packer would be subjected to static strains which stretch the material, causing the'walls of the chamber to become thin and weak, and thereby shorten the effective life of the packer and also tend to develop leaks which wouldbe fatal to the proper functioning of the device. It is of course understood that the replacement of a defective lpacker is a matter involving considerable time and expense.

An important advantage of the present invention is due to the factthat no mechanical pres- Sure, such as the weight of a string of tubing or that of a threaded compression member is employed to deform the packer into sealing position. Thus the use of the present invention greatlyesimpliiles the installation of the packers by the assemblage of the packer stems as part of y an uninterrupted string of tubing having a continuously unobstructed bore.

It'should be noted that the cap members I are freely slidable on the stem I and are not required to act as' a pressure vessel in retaining fluid lmder pressure. The fluid pressure is repacking.

What is claimed is:

1. In a packer the combination of a stem, a chambered packing element of resilient material surrounding the stem and having its intermediate portion secured thereto; and means for inating the chamber in said packing element causing it to expand laterally and contract axially of the stem. the packer expands radially to a greater degree, Y

2. In a packer the combination of a tubular stem, a chambered packing element of resilient material surroimding the intermediate portion tained within the string of tubing of which the 55 ingtheendstoslideaxiallyofthe-stemtoward' the intermediate portion.

3. In a packer the combination of a tubular stem, e chamber-ed pecking element secured a.: its

intermediate portion to the stem, cap members enclosing the ends of the packer and secured thereto, annular pockets formed by the ends of the packer with the stem and the cap members, and means for innating the packer causing it to expand and 'drawing the cap members inwardly on the stem, the packer material in the ends iiowing into the pockets as ythe cap members are contracted.

4. In a packer the combination of a tubular stem, a packer mounted on the stem and having its intermediate portion secured thereto and its end portions free therefrom', and means for inilating said packer causing it to expand laterally and causing the ends thereof to contract axially of the stem to compensate for the lateral expansion. i

5. In means for packing a well, the combination oi a tubular stem arranged to form a section in a string oi' pipe, a packer provided with an internal sleeve closely sin'rounding the tubular stem and aix-external sleeve,.there being an annular :duid space between said sleeves, the boreotsaid stem having accessmeansto the iluid space for inilating said packer by nuid pressure within the stem.

l6. In means for packing a well, the combination of a tubular stern arranged to be connected up as a section in a string of pipe, -a packer provided with an internal sleeve closely surrounding the intermediate portion of the tubular stem and an external sleeve, there being an annular iluid space between'said sleeves, and means for admitting iiuid pressure from the stem into the annular fluid space to innate the packer laterally.

'1. In means for packing a well, the combination oi' a tubular stem arranged to be connected up as a section in' a string of pipe, a packer provided with an internal sleeve closely surrounding the intermediate portion of the tubular stem and an external' sleeve, there being an annular riuid space between said sleeves. and means for admitting `iiuid pressure from the stem into the annular fluid. space to innate the packer laterally, the packer being arranged to contract lonsitudinally on thestem in response to its lateral inflation.

WILLIAM J. BRUNDRED. WILLIAM E.. CROWLEY. ROBERT B. BOSSLER.

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