Title:
Valve device for well conduits
United States Patent 2493650


Abstract:
1' This invention' relates to well apparatus, and more particularly to'valve devices for controlling fluid flbw irr conduits positioned in well bores. Control of the passag of fluid within a well conduit is sometimes determined by a- valve element that is, allowed to- gravitate, or be otherwise-...



Inventors:
Baker, Reuben C.
Althouse Jr., William S.
Application Number:
US65105346A
Publication Date:
01/03/1950
Filing Date:
03/01/1946
Assignee:
BAKER OIL TOOLS INC
Primary Class:
Other Classes:
137/71, 137/797, 166/318, 251/357
International Classes:
E21B34/14
View Patent Images:
US Patent References:
2338719Surface marking signal1944-01-11
2330267Well cementing apparatus1943-09-28
2250813Means for hermetically sealing fluid pressure1941-07-29
2240119Adjustable venturi tube1941-04-29
2002783Valve1935-05-28
1673616Method of and device for cementing wells1928-06-12
1640408Standing valve1927-08-30
1579140Ball cock1926-03-30
1040226N/A1912-10-01
0455913N/A1891-07-14
0373440N/A1887-11-22



Description:

1' This invention' relates to well apparatus, and more particularly to'valve devices for controlling fluid flbw irr conduits positioned in well bores.

Control of the passag of fluid within a well conduit is sometimes determined by a- valve element that is, allowed to- gravitate, or be otherwise- lowered; through the- conduit fluid into sealing- engagement: with a' companion- seating member; Ifi some forms of apparatus; such as side" ported' casing- or- cementing apparatus, it may be desiredl to- close the passage through a sleeve; valve .member disposed originally over the ports- to, enable -hydraulic shifting of the sleeve, to' a' position uncovering the ports; permittifrg passage- of fluid' between- the interior and 'exterior of the-welt'condiit.

Oftentimesc difficulties are encountered in obtaining gravitation of the'valve member through viscous: drilling fluids in' the well-" conduit, or if the- valve' member: does gravitate through such, fluids; it'does so very- slowly, consuming valuable time? Where- the- valve- member is used in, a multiple-stage' cementing operation; its speedy descent' into engagement with" a sleeve- valve is highlywpreferable; in order to open the ports covered -by the' sleeve valve. before the cement slurry th'atimight have'been deposited around the ports' in:- the lower stage cementingĂ˝ operation has an opportunity of'takiilg an-initial set. AN further; disadvantage. of the present gravitational types of valve members is their tendency t:: bounce;: bump -and' gyrate along the walls of the.: conduitsM;through which, they are dropping, whiieh'not onlY slows'their descent through the conduit;- but, frequently damages their' sealing surfaces'and'prevents their efficient'sealing with: the mating-seat in the -sleeve-valve or-other well conduiti: member: Another difficulty in providing a-: proper- leak-proof: seal- is encountered upon inclination of the- gravitational valve member with respeet'to the well' conduit axis: The shape of-the rvalve- member 'may not' permit material deviatiXon:froma coaxial 'position in the conduit, and:-tiliallow-f6rmation of a leak-proof seal with its':coengaging' seat. The requirement: for an efficient leak-proof ' seal under all operational coioditins-becomes"of utmost importance whenandead-column of fluid -is'present below- a sleeve vaiveon which the-valve member is-to seat, inasmuch as'a slight'leak:may-prevent the'building: up' of the- required pressure-' differential across the- sleeve-valve- to, effect' its shifting to port opening position; that is, the pressures on both sides 'ofthe sleeve valvezand engaging valve member become substantially- equalized; preventing hydrauliterelease1 andishifting of the former.

It.is;..accordingly; an objeet"of the present inventiobato provide: a valve member capable of fast downward, travel--through:lthe fluid'inra well" conduit-:into, engagement'-witht its mating= seat A further objectoffthe'invention' is to provide a-valve member'which is not only capable of rapid downward' travel throughĂ˝ the well fluid, as set forth above, but'which is also readily drillable to facilitate its removal ffom the well conduit':after it has served' itsa purpose of closing the conduit bore. Still another object oftlie invention is to provide a-valve member-having such characteristics as to substantially'reditce- its tendency to bounce, bump and gyrate'along the wall -of the well conduit' while gravitating, to its' companion valve seat in the conduit. A further object of the: invention is to provide' a. valve member capable," of making- an efficient' seal against a companion valve seat in a well conduit irrespective of the' inclination of the valve member relative'tb the'condflit axis: This invention, has-other:objects' that'will be20' come apparent fronm-'aconsideration of the'embodinent shown in :thtedirawings- accompanying and' forming part' of the present specification.

This form will now'be described in detail to illustfate the general principles ofthe-invention, but it is to be understood thlat'such detailed'description:is not'to- be'taken'rifi a'-limited sense, since the, scope, of the" inventiobn is best defin-ed' by the claims: appendedtlheretoi Referring to- tie drawings: Figure 1 is a longitiudinal'section through a well casing-, withl thie valve device' parts disclosed in one relative'position; Figure 2 is a viewisimilar to Figure 1; with the gravitational valve member' i' inclined position; S Figure-'3 is a cross-section taken along the line 3-3_in Figure 2; 'and Figure 4: is an- enilged, partial' longitudinal section' of part;of'the' valve device shown in Figure 1; The invention is disclosed 'by way of example in the' drawings'as applied to a -string' of well casing having a collar' ID1connecting adjacent upper' and lower casing: sections' II, 12 together in -spaced relation. This :collar has lateral ports 13 normally closed 'by"a sleeve valve" 14 having side seals 15 engaging:the" wall of the collar on: opposite :sides- of its ports: The sleeve.valve is held in this closed positioni originally by one or more shear screws' 16' extending- betwven the collar I0 and sleeve i- 4 The sleeve valve'ihas'a ceitral passage 17 whose' upper leading- wallf portion- 18 tapers in' an.-upward and outward directiorn from a'medial throat 19 to form an inclined seating surface for a companion- valve :member 20. Tlhevalve member is of the gravitational typet; atndis'designed-to drop. downwardly through- th'ewell casing or conduit intod engagement'with the seat 18'ifn the sleeve valve; to close-its central passage in and allow the pressure'-of' the- fluid in the casing above the valve member and sleeve valve to be increased sufficiently for the purpose of shearing the screws 16 and shifting the sleeve valve member 14 downwardly to port opening position, as determined by abutting of the lower end 14a of the sleeve with a suitable stop, which may be the upper pin end 12a of the lower adjacent casing section 12. With the ports 13 in this position, fluid may be circulated from the interior of the well casing, through the open ports to the casing exterior.

The gravitational type of valve member 20 includes a hollow body 21 of generally tear drop, streamlined shape, filled either completely or partially with a relatively dense weighting material 22, such as lead or mercury. The forward or nose end 23 of the body is of spherical shape, with a spherical seal 24 of rubber or other elastic material mounted on it. As disclosed in the drawings, the nose 23 of the body has a hemispherical surface 23a adjacent an external body groove 25, the seal 24 also being hemispherical and merging into an upper rim 26 of cylindrical exterior having an internal flange 27 positioned within the body groove. Actually, the seal 24 is made slightly smaller than the forward end 23 of the body, in order to be stretched over the latter and obtain secure and snug engagement between the contacting spherical surfaces and between the flange 27 and surfaces defining the body groove 25.

The rearward portion 28 of the body is generally conical or conoidal in shape, converging gradually from the nose portion 23. Stabilizing fins or vanes 29 are disposed at the rear end of the body and are generally radial of the body to prevent gyration of the valve member as it is dropping through the well conduit.

The outer spherical surface 24a of the valve member seal 24 is of such a diameter with respect to its coengaging seat 18 in the sleeve valve as to make a continuous circular seal therewith, which is completely leak-proof regardless of the position of inclination that might be assumed by the valve member 20 relative to the conduit and sleeve axis. The valve member is made sufficiently long with respect to the external diameter of the sealing surface 24a of the seal that, when engaged on the sleeve valve seat 18 with the fins 29 disposed against the wall of the conduit, the outer spherical surface 24a of the seal still makes a complete circular seal with the inclined seating surface of the sleeve valve. As shown in the drawings, the length of the valve member is about three times the external diameter of the seal, but this proportion may be altered, depending upon the inside diameter of the casing in which the member is used, the external radius of the seal 24, and the extent of lateral projection of the fins 29, which are illustrated as extending outwardly from the axis of the body about the same distance as the radius of the external sealing surface 24a.

As shown in the drawings, when the valve member 20 engages its seat 18 in coaxial position, a uniform, circular elastic seal is made with the seat, and leakage therebetween cannot occur (see Figure 1). Upon inclination of the valve member with respect to the axis to its fullest extent, as when the fins 29 are engaging the wall of the casing (see Figures 2 and 3), the spherical surface 24a is still making a complete circular seal with the seat of the valve member, having merely rotated several degrees about its center 24b. As a result of the spherical seat contacting surface 24a, various degrees of inclination of the valve member with respect to the axis of the conduit and sleeve valve still produce an efficient seal that is leak-proof in all respects. The leakproof characteristic is materially enhanced by the rubber or other elastic material of which the seal 24 is made, which makes it conform with minor irregularities or depressions that might be found in the seating surface 18 of the sleeve valve 14. Moreover, it is to be noted that the radius of the exterior of the body nose 23 itself is greater than the radius of the sleeve throat 19, to insure compression of the elastic sealing material between the body 21 and sleeve 14 upon imposition of pressure on the body, and to forestall potential dissipation of the seal by hydraulic pressure action thereupon, which might occur if the body nose radius were less than the throat radius, and thus allowed a substantial annular space through which the seal material could be blown.

The descent of the valve member 20 through the fluid in a well conduit is accelerated substantially by use of the body 21 containing the heavy lead or other weighting material 22. It is to be noted that most of the weighting material is in the leading portion of the body, which maintains its center of gravity closer to the spherical seal 24 and facilitates dropping of the valve member in a straight line through the well conduit. Such straight line dropping is assisted by the gyration preventing action of the stabilizing fins 29 while the valve member is gravitating through the casing fluid.

The lead weighting material 22 adds substantially to the gravitational force available in moving the valve member downwardly through the fluid in the well conduit, since it adds more weight per unit of frontal area of the valve member displacing the fluid to one side. Such descent or gravitation of the valve member is further enhanced by the tear drop or streamlined shape of its body, which allows a minimum of fluid eddying or drag on the valve member, and insures smooth streamlined fluid flow thereover as the i45 valve member passes downwardly through the casing fluid.

The hollow body 21 of the valve member is made of a suitable, rigid, drillable material, such as magnesium alloy or aluminum. This body has a relatively thin section to permit the use of a maximum amount of lead weighting substance 22. The use of a substance like magnesium alloy or aluminum for the body 21 provides a material capable of resisting much more marring or deformation than the lead material itself, and retains the entire valve device in its initial undeformed condition during its descent through the well conduit into engagement with the sleeve valve. The use of lead, or a similar pliant ma0o terial, alone for the entire valve member would subject it to substantial deformation during downward descent through the well casing, and possibly result in its failure to seal properly with its mating valve seat. However, by combining 05 the two materials, namely, an envelope 21 of rigid and nondeformable magnesium alloy or aluminum filled with an internal weight of lead or similar substance 22, the gravitational advantages of the lead are retained while its deformation disadvantage is eliminated.

In the use of the arrangement disclosed for multiple stage cementing purposes, let it be assumed that cement slurry has been displaced from the well conduit at some point below the collar 10, as through a casing shoe (not shown).

-5S Thereafter,t-he valve'member 20 is dropped from the top of Athe-well bore -through the well con* duit; and descends speedily into engagement with -the valve seat :18 to allow fluid pressure to be 'built up for the purposei of shearing the screws 16 :and shifting the valve 14 downwardly to port 'opening position. Such -rapid travel ;insures -opening of the ports :13 prior .to the time that any cement slurry, which -'may have been. deposited around the ports: by 'the lower stage cementing operation, has an.opportunity of taking an initial set. This port enclosing slurry, which is still in a plastic state when'the ports are opened, can -..be -circulated readily from .the :annulus around the casing by pumping fluid down -the casing and out of the ports.

Ordinarily, in the performance of multiple stage cementing operations, the fluid below the' upper 'stage; collar is a dead, substantially incompressible column -after the lower stage has been cemented.

The making of an efficient seal under 'all conditions between the valve member 20 and the sleeve -valve 14 thus becomes of paramount importance, :since even a slight degree of leakage would equalize the-pressures on both sides of the sleeve valve and preclude shearing of-the screws 16, which, of course; would prevent opening of the .ports 13.

By .applicants' arrangement, an :efficient' seal is obtained and port opening assured.

Although described in conjunction with a sleeve valve for controlling lateral ports in a well conduit, the valve member has other uses. For example, it could be employed as a bridging member to close the bore through the well conduit by engaging an immovable seat therein.

After the cementing operation has taken place and the cement has hardened, it is usual practice to drill out internal casing obstructions. The running of a drill bit in the casing to the position of the valve member 20 and sleeve 14, and the drilling out of these two members, can take place very readily, since they are all made of readily drillable materials.

Having thus described our invention what we claim and desire to secure by Letters Patent is: 1. A valve device for gravitation through a well conduit, including a hollow impermeable body of generally tear drop shape having a spherical nose portion and stabilizing fins on its tail portion, and a weighting material in said hollow body having a greater specific gravity than the material of said body.

2. A valve device for gravitation through a well conduit, including a hollow impact resisting body having a forward portion whose outer surface is a segment of a sphere and a rearward portion converging gradually from said forward portion, and a weighting material in said hollow body having a much greater specific gravity than the material of said body.

3. A valve device for gravitation through a well conduit, including a hollow body of readily drillable material having a generally spherical forward portion and a rearward conoidal portion converging gradually from said forward portion, a unitary readily drillable weighting material in said hollow body having a much greater specific gravity than said body material, and radial fins secured to and extending from said rearward portion.

4. A valve device for gravitation through a well conduit, including a rigid, non-deformable hollow body having a generally spherical valve seating surface thereon and a hollow portion extending longitudinally from said surface, and a weighting zmaterial in: said hollow -body ,substantially .completely flling said longitudinally extending hollow 'portion.and.having a.greater specific gravity than the material of said body.

.5 5. A valve'device for gravitation through a well ,conduit, including a rigid, non-deformable hollow body ;of -readily drillable material -having a valve -seating surface thereon and a hollow -portion extending longitudinally from said surface, and' a readily drillable weighting material ifilling said -hollow body, including said longitudinally extending hollow portion; and having a much igreater .specific gravity than the-material of said body.

S6. A valve device for use in a well conduit, 'including a rigid body of readily drillable materialbhaving aspherical nose portion and a circular groove -adjacent said portion, said body further including a longitudinally extending portion con,verging.gradually from said nose portion, and an elastic spherical 'seal mounted on said body in snug engagement with said spherical nose portion and merging smoothly into said longitudinally 'extending portion, said seal having a flange positioned -within said groove.

,5 7. .A valve-device for :use in a well conduit, including a hollow body having a -spherical forward portion and a rearward conoidal portion merging substantially into and converging gradually-from-said forward 'portion, a weighting;material in said hollow body having a much greater specific gravity than the material of said body, and an elastic spherical seal on said spherical forward portion.

8. A valve device for use in a well conduit, including a hollow body of readily drillable material having a spherical forward portion and a rearward conoidal portion converging gradually from said forward portion, said body also having a circular groove adjacent said forward and rearward portions, an elastic spherical seal mounted on said body in snug engagement with said spherical forward portion, said seal having a flange positioned within said groove, and a readily drillable weighting material in said hollow body :45 having a much greater specific gravity than said body material.

9. A valve device for gravitation through a well conduit, including a hollow body of generally tear drop shape having a spherical nose portion and stabilizing fins on its tail portion, a weighting material in said hollow body having a greater specific gravity than the material of said body, and an elastic spherical seal on said nose portion.

10. A valve device for gravitation through a well 5r5 conduit, including a hollow body of readily drillable material having a generally spherical forward portion and a rearward conoidal portion converging gradually from said forward portion, a readily drillable weighting material in said hol6', low body having a much greater specific gravity than said body material, and an elastic spherical seal on said forward portion.

11. A valve device for gravitation through a well conduit, including a hollow body of readily S. drillable material having a valve seating surface thereon and a hollow portion extending longitudinally from said surface, a readily drillable weighting material filling said hollow body and its hollow portion and having a much greater specific gravity 7o than the material of said body, and an elastic seal on said valve seating surface.

12. A valve device for gravitation through a Well conduit including a hollow metallic body having a generally spherical valve seating surface thereon and a hollow portion extending longitudinally from said surface, and a weighting material in said hollow body and its hollow portion having a greater specific gravity than the material of said body.

13. A valve device for gravitation through a well conduit, including a rigid, non-deformable body having a generally spherical valve seating surface thereon and a hollow portion extending longitudinally from said surface, and a weighting material filling said longitudinally extending hollow portion and having a greater specific gravity than the material of said body.

14. A valve device for gravitation through a well conduit, including a rigid, non-deformable body of readily drillable material having a valve seating surface thereon and a hollow portion extending longitudinally from said surface, and a readily drillable weighting material filling said hollow portion and having a much greater specific gravity than the material of said body.

15. A valve device for use in a well conduit, including a body having a spherical forward portion and a rearward conoidal portion converging gradually from said forward portion, and an elastic spherical seal on said spherical forward portion merging smoothly into said conoidal portion.

16. A valve device for use in a well conduit, including a body of readily drillable material having a spherical forward portion and a rearward conoidal portion converging gradually from said forward portion, said body also having a circular groove adjacent said forward and rearward portions, an elastic spherical seal mounted on said body in snug engagement with said spherical forward portion and merging smoothly into said conoidal portion, said seal having a flange positioned within said groove.

REUBEN C. BAKER.

WILLIAM S. ALTHOUSE, JR.

REFERENCES CITED The following references are of record in the 15 file of this patent: UNITED STATES PATENTS Number 373,440 455,913 1,040,226 1,579,140 1,640,408 1,673,616 2,002,783 2,240,119 2,250,813 2,330,267 2,338,719 Name Date Chapman _----- Nov. 22, 1887 Walker -------- _ July 14, 1891 De Lukaesevics ----- Oct. 1, 1912 Phillips ------- Mar. 30, 1926 House --.------ .-- Aug. 30, 1927 Boynton ------ - June 12, 1928 Long---------- May.28, 1935 Montgomery ---- - Apr. 29, 1941 Rea ------------- July 29, 1941 Burt ----------- Sept. 28, 1943 Holt -------------- Jan. 11, 1944