US2627314A - Cementing plug and valve device for well casings - Google Patents

Description

Feb- 3, 1953 R. c. BAKER ET AL 2,527,314

CEMENTING PLUG AND VALVE DEVICE FOR wELL CASINGS Filed Nov. 14, 1949 TVJ K .vv u u @WEEE A?. E E fi@ m wwf MMM /QTTOEWEYIS Patented Feb. 3, 1953 CEMENTING PLUG AND VALVE DEVICE FOR WELL CASINGS Reuben C. Baker, Coalinga, and Benjamin Lewis Austin, Long Beach, Calif., assignors to Baker Oil Tools, Inc., Vernon, Calif., a corporation of California Application November le, Nilis, Serial No. 127,189

(Ci. 16S- i) 10 Claims. 1

The present invention relates to subsurface well devices, and more particularly to combination plug and valve devices adapted for downward movement through well conduits, such as casing strings, in the performance of several desirable functions therein.

This application is a continuation-in-part of our application for Positive Shut-Off Ported Casing Apparatus, Serial No. 22,886, iiled April `23, 1948.

An object of the present invention is to provide improved cementing plugs especially useful at the upper end of a charge of cementitious material, and capable oi eiiectively closing a passage in a well bore upon engaging a companion valve seat.

Another object of the invention is to provide a cementing plug that is slidable along the wall of a casing string, and capable of cooperating with a sleeve valve to effect its hydraulic shifting from port closing position without interfering with the passage of fluids through the ports.

A further object of the invention is to provide a lcernenting plug adapted to slidably seal with the wall of a well casing, and also capable of being squeezed into a cooperable valve seat t0 obtain positive sealing with the seat and to insure that the plug will not interfere with fluid passage through a side port in the well casing above the seat.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of several forms in which it may be embodied. Such forms are shown in the drawings accompanying and forming part of the present specification. These forms will now be described in detail, illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best deiined by the appended claims.

Referring to the drawings:

Figure l is a longitudinal section through a ported well apparatus, with the ports open, after having been closed, and with a top cementing plug and valve device descending towards a cooperable valve seat;

Fig. 2 is a view similar to Fig. 1, with the ports reclosed and with the top cementing plug and valve device squeezed into an upper sleeve valve;

Fig. 3 is a combined longitudinal section and side elevation through a modiiied form .of cementing plug and valve device.

As disclosed in the drawings, a casing collar A has its upper and lower ends threadedly confi O ` the tubular member groove 23. u

2 nected to the ends of upper and lower casing sections B, C forming part of a casing string ladapted to be run in a well bore to position the collar at 'the desired location therein.

`The collar A includes -a tubular member I0 whose lower end Consists of a coupling I I th'r'eaded onto the upper end of the lower casing section C. A stop member I2 is ysecured to the exterior of the coupling, as by the use of welding material I3, to serve a purpose described below.

The tubular member I0 lhas a plurality of circularly spaced side ports I`4 through which fluids are adapted to pass between the interior and exterior of the collar apparatus. These Aports are closed initially by a lower inner sleeve valve member I5 having seal rings I6, II disposed inl suitable ring grooves I8 on opposite sides of the ports. These rings may be of rubber and of round cross-section 'to prevent leakage thereby in both longitudinal directions. y

The lower inner sleeve valve member I5 is re tained in position to locate its seal rings I6, Il on opposite sides of the ports I4 by one or more frangible devices in theform of shear screws I9 threaded through the tubular member IIJ and extending into the valve member.

It is to be noted that the inside diameterof the tubular member I0, atthe region where it is engaged by the lower seal ring I1, is less than the internal diameter of 'a groove '23 in the inember I0 immediately below this region. Also, the sleeve valve member I5 is reduced in 'external diameter to form `a peripheral groove 24 below the lower seal ring I'I, in which a split, inherently expansible stop ring 25 is located. The stop ring has an upper inner inclined surface 26 Vtapering downwardly and inwardly for cooperation with a corresponding tapered surface 2l on the base of the peripheral groove 24. The length of the groove 24 is much greater than the length of the stop ring to permit downward movement of the sleeve valve member I5 relative to the stop ring. u

The ring 25 is received within the enlarged diameter portion 23 of the tubular member., ,Ifhis enlarged portion is much longer than. the height of the stop ring. The stop ring may rest upon a shoulder 28 provided A by the lower end', of `the peripheral groove 24, theupper end of the-stop ring being engageable with an upper lshoiilder!) of the peripheral groove 24. Downward' movement of the stop ring is limited by its engagement with the shoulder `BEI iorr'nedl by the lower end oi The shear screws I9 are adapted'to be dise 3 rupted and the lower inner sleeve valve member I5 moved downwardly to a position in which the upper seal ring I5 is disposed below the ports I4. The ports are then open to the passage of uid between the interior and exterior of the apparatus (Fig. l).

After the ports have been opened, it is desired to reclose them. To accomplish this purpose, an external sleeve valve member 3| is provided on the tubular member I0. This external member has a plurality of longitudinally spaced seal rings 32, 33 disposed in internal grooves 34 and slidably engageable with the outer surface of the tubular member I5. The outer member 3| has an upwardly extending cylinder 35 integral therewith, or otherwise suitably secured thereto, which is slidable along an enlarged portion Ida of. the tubular member.

The outer member 3| is retained initially in an upward position, in which it does not close the ports |4, by one or more shear screws 36 threaded through the cylinder 35 into the enlarged portion ma of the tubular member. These screws are disruptable hydraulically by iluid pressure, including fluid under pressure entering through one or more elongate ports, slots or openings 31 in the tubular member into a cylinder space 38. This space is formed between the enlarged portion i3d of the tubular member, the cylinder skirt 35 and the part 3Ia of the sleeve valve member carrying the seal rings 32, 33. Leakage in a downward direction between the sleeve valve member 3| and Vtubular member I0 is prevented by the seal ring 32. Leakage in an upward direction therebetween is prevented by a seal ring 33 disposed in a peripheral groove 45 in the enlarged portion lila of the-tubular member, which sealingly engages the inner surface of the cylinder 35.

When sufcient hydraulic force is exerted on the outer sleeve valve member 3 I, the shear screws 33 will be disrupted and the outer sleeve valve member 3| shifted downwardly to a position in which its seal rings 32, 33 are located on opposite sides of the ports I4, closing such ports against passage of fluids therethrough in both directions between the interior and exterior of the apparatus. This position of the sleeve valve member 3| is determined by engagement of its depending skirt 4| with the upper end of the stop member |2. It is to be noted that the upper portion of the skirt 4| is spaced outwardly from the tubular member |I| so as to avoid interfering with passage of fluids through the ports I4 after they have been opened. This fluid flows through the ports I4 and through slots 4m in the lower end of the skirt. The end is slidable upon the member I0 and has a lower, knife-like edge 4|b capable of cutting through any materials that might coat the member I, or tend to prevent downward movement of the outer sleeve valve member 3|.

After the outer sleeve valve member 3| has 'been shifted downwardly to port closing position,

it is prevented from moving upwardly again by a latch or lock ring 42 disposed Within a peripheral groove 43 in the tubular member I l) above its seal ring 39. This lock ring consists of a split, inherently expansible member having a reduced diameter lower portion 42a forming a shoulder 44 `with the upper portion 42h. The shoulder is inclined outwardly in a downward direction to a slight extent.

' When the outer sleeve valve member 3| has been forceddownwardly to essentially its fullest extent, the upper end 35a of the cylinder is disposed below the shoulder 44 of the split lock ring, but not below the lower end of its reduced diameter portion 42a. As a matter of fact, the upper part of the cylinder 35 will be in engagement with the outer surface of the reduced diameter portion 42a, the lock ring 42 inherently expanding outwardly to a certain Aextent upon riding of the cylinder oi its upper portion 4212. Any tendency for the outer sleeve valve member Y 3| to move upwardly will be limited by engageshear screws ment of the upper cylinder end 35a with the lock ring shoulder 44, the lock ring being forced against the upper end of the peripheral groove 43. To insure against inward forcing of the lock ring 42 from engagement with the end 35a of the cylinder, the latter is tapered in the same direction as the shoulder 44, so that the two will remain in snug contact with one another.

The force of iluid under pressure is prevented from acting upon the external sleeve valve member 3| by an upper inner sleeve valve member 45 having longitudinally spaced seal rings 45 disposed in ring grooves 41 on opposite sides of the elongate ports or slots 31. This valve member is held in position by one or more shear screws 48 threaded through the tubular member ||l into the upper valve member 45. Disruption of the shear screws 48 and downward shifting of the upper sleeve valve member 45 will expose the ports 31 and permit fluid under pressure to pass through the latter into the cylinder space 38, in order to assist in shearing the cylinder screws 35 and moving the outer sleeve valve member 3| downwardly to port closing position.

The upper inner sleeve valve member 45 is not only used for the purpose of controlling the pas sage of uid through the elongate ports 31, but is also used in assisting downward movement of the external sleeve valve member 3| to port closing position.

To accomplish this latter purpose, the upper inner sleeve valve member 45 and external sleeve Valve 3| have an intervening lost motion connection. As specifically disclosed in the drawings, the outer sleeve valve 3| is formed with a plurality of inner keyways 36, in which are received the `lug or arm portions 3| of keys 82 secured to the upper inner sleeve member 45 and extending outwardly through the elongate ports or slots 31. Each key includes a leg portion 83 depending from the arm portion 8| and adapted for movement within the tubular member i5 with the upper inner valve member 45.

It is to be noted that the arm 8| of each key is disposed originally above the lower end or shoulder 84 of the keyway 80. This arrangement is provided for the purpose of permitting the inner valve member 45 to move downwardly to an extent sufficient to shift the upper seal ring 4S below the upper ends of the ports 31, and thereby allow fluid to pass into the annular cylinder space 38 for action upon the sleeve 3| to effect shiftf' ing, or at least assisting in shifting, the sleeve Valve 3| downwardly to port closing position. `As described in detail below, once the elongate ports 31 are open, iiuid under pressure may enter the cylinder space 38 through these ports, disrupt the shear screws 35 and shift the outer valve inem- `ber 3| downwardly to port closing position. Ir" this hydraulic force is insuflcient, then pressure may be imposed upon the entire crossnsectional area of the upper inner sleeve valve 45, which will be transmitted to the external sleeve valve 3| lthrough the keys 62 and abutting shoulders 84.

Asv stated above, the lower sleeve valve member I5 is held initially in closed position by its I9. Similarly, the upper sleeve atomare valve member lis held in closed position over the `elongate ports 31 by shear screw-s 48, preferably closely adjacent or in abutting relation with 'the upper end of lthe lower valve member I5. The upper valve 45 has a central bore VIll whose wall tapers downwardly and inwardly. Similarly, the lower valve member I5 has a downwardly and inwardly tapering central bore 50, which, in effect, forms a continuation of the upper member bore 49. The cylinder screws 36 hold the outer valve member 3| in its upper position.

With both sets -o ports I4, 31 closed, a fluent material, such as cement slurry, may be pumped directly into the casing string and through the central bores or passages 43, 3e in both sleeve valve members 45, I5, for discharge from the well casing at some point below the collar, as, for

`example, from a casing shoe (not shown). This charge of cement slurry will pass upwardly through the annulus around the casingstring and may extend approximately to the location of the collar A, or slightly thereabove.

When it is desired to eject a second or upper charge of cement slurry through lthe collar ports I4, a trip device or plug `member 5I is dropped into the wellcasing and is allowed to gravitate through the fluid therein into engagement with the wall oi the central bore in the lower sleeve valve member I5.

Pressure may now be applied to the iluid in the casing above the trip member El and sleeve I5 in an amount suiiicient to shear the screws I3 and shift the lower sleeve valve member I5 downwardly to port opening position, as shown in Fig. 1.

Downward movement of the lower valve member is limited by engagement of the stop ring 25 with ythe shoulder 30 of the tubular member Ill, and of the shoulder 23 on the lower sleeve member I5 with the stop ring. Washing fluid, followed by cement slurry or other cementitious material, may new be discharged outwardly through the open ports I4, passing through the annular space between the tubular member I0 and the depending skirt 4I of the outer valve member 3 I, and through the slots 4 i a in the lower end of this skirt, for upward movement through the annulus around the collar A and casing string.

Upon discharging the required quantity of cement slurry, the outer sleeve valve 3| is forced downwardly to port closing position. IThis act may be accomplished by placing a top cementing plug 58 at the upper end of the charge of cement slurry pumped outwardly through the ports I4. This plug will come to rest within the bore 43 of the upper sleeve valve member 45, allowing the fluid inthe casing string above the collar A to be pressurized to an. extent suihcient for shearing the screws 48, to shift the upper inner valve member 45 downwardly to a position in which the upper ends of the elongate ports 31 are open.

The top cementing plug 58 disclosed in the drawings is of a composite character. It includes a lower nose 59, which may be made of magnesium., aluminum or other suitable, readily drillable material, having a tapered periphery 6D adapted to conform to the taper of the passage 43 in the upper sleeve 45. This nose is so proportioned as to seat within the passage and cause the top oementingplug A58 to come to rest therewithin. From its tapered nose, the lower end of the plug is integral with a central shank 6I terminating in a vflange 62, received within a rcompanion bore 'and recess 33 of a flexible portion B5 of the cementing plug. aresuitably vulcanized together.

The llexible plug 65 is formed essentially of rubber or similar material. It has an inwardly7 compressible body portion 'lil defined by tapered forward and rearward surfaces 1I, 12 merging into an annular peripheral sealing surface 13 slidably engageable with the wall of the well casing. The plug 65 also has a tail portion 14 terminating in a fluted guide 15. Its annular sealing portion includes an upwardly extending lip 16 adapted to be forced outwardly by fluid pressure against the wall of the casing.

The tapered nose 53 on the lower plug portion has a greater diameter than the minimum diameter through the upper sleeve valve 45. As a result, it comes to rest within the tapered bore 49 fof the latter, closing it against passage of fluid and allowing pressure to be built up in the casing fluid above the cementing plug 58, sufiicient in extent to shear the screws t3 and shift the upper member de downwardly to a position limited by `engagement of the key lugs 8l with the shoulders 34 forming the lower end of the keyways 48l) in the outer sleeve 3l. When in this position, the upper ends of the elongate ports 31 are exposed, allowing fluid to pass into the cylinder space 33 for the purpose of shearing the cylinder screws 33 and moving the outer sleeve 3I downwardly yto port closing position (Fig. 2)

A standard top `cernenting plug would not permit uid to pass -by it and enter the ports 31. The flexible plug 35 described above, however, will have its body 'lll and annular sealing portion 13 deformed inwardly to a sufficient extent to compress the rubber material into the tapered passage 49 through the upper inner valvemember 45, sealing 01T this passage completely,I while removing the annular sealing portion 13 of the plug from engagement with the casing wall or inner wall of the tubular member Ill (see Fie'. 2). The plug, therefore, offers no restriction or barrier to passage of nuid through the ports -31, for aotion upon the outer sleeve valve member 3|.

The top cementing plug 58 serves its normal function of conning the charge of cement slurry in advance of it, by slidably sealing with the wall of the well casing during its downward passage. It insures the release of the upper valve member 45, to open the elongate ports 31, since it is squeezed to a substantial extent into the sleeve valve member 43. Such squeezing action insures a tight seal with the sleeve valve 65, and also removes the peripheral sealing portion 13 cornpletely from engagement with the casing wall, in view of the squeezing of this peripheral portion into the sleeve valve. As a result, the peripheral sealing portion cannot interfere with the ability of fluid to pass-through the elongate ports 31, for the purpose of hydraulically shifting the outer sleeve valve member 3l downwardly to a position closing the portsl Ifl.

squeezing of the peripheral portion 13 into the sleeve valve occurs as a result of locating such peripheral portion substantially adjacent the nose or valve head 5S of the device. The leading face 'il of the fiexible cementing plug body 1% extends from the peripheral sealing portion 13 to the valve head 59, and cooperates with the tapered wall iii in the sleeve valve i5 to `assist in bodily compressing the peripheral portion 1S within the sleeve valve 45.

A modif-led form of cementing plug and valve device is illustrated in Fig. 3, in which a generally spherical nose or head 33a depends from a These two par ts central shank Bla fitting within a companion central bore 63a of the flexible cementing plug. The shank extends through the body portion 19 of the lflexible plug and also through its tail portion 14, the central shank terminating in an upper flange 62a disposed adjacent the fluted guide 15, which is integral with the tail portion.

As in the other form of invention, the flexible plug has a peripheral portion 13a for slidable sealing with the wall of the well casing, as well as an upwardly extending peripheral lip 16a. In addition, the leading surface 1hr is present in the flexible body, converging from the peripheral portion 13a towards the generally spherical nose or head 59a.

To insure against any leakage between the valve head 59a and the tapered wall 49 of the sleeve valve 45, a spherical seal is provided over the surface of the spherical valve head 59a. This spherical seal may be made of rubber or rubber-like material, and is preferably integral with the flexible cementing plug portion of the device. The seal extends around the head 59a and terminates in an upwardly directed annulus IDI fitting within an end groove m2 in the forward or lower portion of the valve head 59a, for the purpose of securing the lower end of the seal firmly within the valve head.

In all respects, the device illustrated in Fig. 3 functions in the same manner as the cementing plug and valve device shown in Figs. 1 and 2. The plug slidably seals with the wallof the well casing in maintaining the cement slurry separate from the displacement fluid above the plug. Its head and seal 59a, |50 can ft within the valve sleeve 45 with the seal lill] insuring against leakage thereby. The peripheral portion 13a can also be squeezed into the tapered portion 69 of the sleeve valve 45, to insure that a leakprcof seal is present between the device and the sleeve Valve 45, and also to remove such portion 13a completely from contact with the casing wall. In this manner, fluid above the plug device can pass freely through the elongate ports 31 into the cylinder space 38, to move the outer sleeve valve 3| downward through hydraulic action.

The inventors claim:

l. A cementing plug, including a forward rigid valve head portion and a trailing inwardly compressible elastic body having a peripheral portion for slidable sealing engagement with the wall of a well conduit, said body also having a leading portion adjacent said head portion which has an outer surface converging from said peripheral portion to said head portion, the maximum diameter of said valve head portion being materially less than the maximum diameter of said peripheral portion.

2. A cementing plug, including a forward rigid valve head portion and a shank extending'upwardly from said head portion, an inwardly compressible elastic body receiving said shank, said body having a portion adjacent said head portion for slidable sealing engagement with the wall of a well conduit, the maximumdiameter of said valve head portion being materially less thanthe maximum diameter of that portion of the body which slidably engages the wall of the well conduit.

3. A cementing plug, including a forward rigid valve head portion and a shank extendingupwardly from said head portion, said shank having a flange at its upper end, an inwardly compressible elastic body receiving said shank and flange, said body having a portion adjacent said head portion for slidable sealing engagement with the wall of a well conduit, the maximum diameter of said valve head portion being materially less than the maximum diameter of that portion of the body which slidably engages the wall of the well conduit.

4. A cementing plug, including a forward rigid valve head portion, a rigid shank integral with and extending upwardly from said head portion, an inwardly compressible elastic body receiving said shank, said body having a peripheral portion for slidable sealing engagement with the wall of a well conduit, said body also having a leading portion adjacent said head portion which has an outer surface converging from said peripheral portion to said head portion, the maximum diameter of said valve head portion being materially less than the maximum diameter of said peripheral portion.

5. A cementing plug, including a forward rigid valve head portion and an inwardly compressible elastic body having a portion adjacent said valve head portion for slidable sealing engagement with the wall of a well conduit, and an elastic seal integral with said body and disposed on the forward face of said head portion.

6. A cementing plug, including a forward rigid generally spherically curved valve head portion, an inwardly compressible elastic body having a portion adjacent said valve head portion for slidable sealing engagement with the wall of a well conduit, and an elastic generally spherically curved seal integral with said body and disposed over said spherically curved head portion.

7. A cementing plug, including a forward rigid valve head portion and a shank extending upwardly from said head portion, an inwardly compressible elasticl body receiving said shank, said body having a portion adjacent said head portion for slidable sealing engagement with the wall of a well conduit, and an elastic seal disposed over said valve head portion, said seal being integral with said body.

8. A cementing plug, including a generally conical forward rigid valve head portion and a shank extending upwardly from said head portion, an inwardly compressible body receiving said shank, said body having a peripher-al portion adjacent said head portion for slidable sealing engagement with the wall of a well conduit, said body also having a leading portion which has an outer surface converging from said peripheral portion to said head portion.

9. A cementing plug: including a forward generally spherically curved rigid valve head portion; a rigid shank integral with and extending upwardly from said head portion; an inwardly compressible elastic body receiving said shank, said body including a trailing portion disposed around said shank, a peripheral portion adjacent said head portion for slidable sealing engagementwith the wall of a well conduit, and a leading portion having an outer surface converging from said peripheral portion to said head portion.

' 1i). A cementing plug: including a forward generally spherically curved rigid valve head portion; a rigidl shank integral'with and extending upwardly from said head portion; an inwardly vcompressible elastic body receiving said shank, -A-said body including a trailing portion disposed around said shank, a peripheral portion adjacent said head portion for slidable sealing engagement with the wall of a well conduit, anda leading por- .tion having an outer surface Vconvergingfrom said peripheral portion to said head portion; and

9 a spherically curved seal on said sphercally curved valve head portion, said seal being integral with said body.

REUBEN C. BAKER. BENJAMIN LEWIS AUSTIN.

REFERENCES CITED The following references are of record in the le of this patent:

Number 10 UNITED STATES PATENTS Name Date Wickersham July 28, 1931 Manning May 23. 1933 Morrisett Aug. 15, 1939 Baker Apr. 9, 1940 Brown Oct. 7, 1941 Baker Mar. 6, 1945 Baker et al Jan. 3, 1950

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