US2832617A - Stationary, well head preventer - Google Patents

Description

April 29, 1958 w. c. GIBSON v 2,832,617

' STATIONARY, WELL HEAD PREVENTER Filed May 1s, 1954 ilite States Patent i STATIONARY, WELL HEAD PREVENTER Wilfred C. Gibson, Fullerton, Calif., assigner to Shaffer This invention has to do with headworks fittings of deep well apparatus, and is a stationary, blow out preventing packer assembly.

A cardinal purpose of this invention is to provide a blow out preventer in which there is a tubular, thickwalled mass of elastic material constituting a single sealing off element whereby to effect a shut off either on an axially interposed pipe or tool section in a casing head iitting, or to be so axially compacted as to itself close its axial bore and thus form a stopple against liuid iiow at and through the packer clement.

When such a large mass of packing is axially compacted its natural tendency to expand to its normalor original shape is destroyed. Therefore, an additional purpose of this invention is to provide automatic means permitting7 desired mechanical compaction for shut off function and which acts, when compacting pressure is released, to spring or restore the body mass of the packer out to its normal-size condition.

The invention resides in certain advancements in this art as set forth in the ensuing disclosure and has, with the above, numerous additional objects and advantages as hereinafter developed, and whose constructions, combinations and sub-combinations, and details of means and manner of operation will be made manifest in the following description of the herewith illustrative embodiment; it being understood that modifications, variations, adaptations and equivalents may be resorted to within the scope, spirit and principles of the invention as it is claimed in conclusion hereof.

Figure l is an axial section of the partly in elevation. the armor fingers.

ln its preferred embodiment the assembly includes an upper housing 2 the lower end of which aiords a rim shoulder 2s on which lands the upper end of an encompassing bonnet 3 which is joined by suitable screw threads 3s to a lower cylinder 4 having a basal flange 4f to attach to a lower apparatus fitting, not shown. These joined parts have an axial, through passageway or bore hole 5 for well pipe or working tool sections, as is well known.

A tubular piston 6 has a lower head 6h packed and working in the cylinder 4, and has fixed to its upper end, as by screws 7, a head or top disc 8 which in the illustrated lowered position of the piston 6 rests close to a separator plate 9 which is clinched tight between the housing and the attached cylinder. The plate 9 has a pressure fluid duct 9d for service of motive iluid to the under face of the disc 8 to force the piston upward. Conversely, a motive iiuid duct 9c delivers the iluid downward onto the upper face of the piston head 6h, thereby making the piston of double action. The plate 9 is packed onto the reduced hub of the piston.

The disc 8 constitutes a circular, transverse ram on Whose upper face rests a circular gang of segmental armor fingers 10 Fig. 2, which are partially embedded in the lower end of a thick-walled, tubular mass of a suitpacker assembly, Figure 2 is a plan view of one of 2 able elastic material (rubber or the like) forming a massive packer 11. The upper end of the packer lodges on an embedded, circular gang of segmental, Varmor lingers 12 similar to iingers 10. t

If the piston disc ram 8 is now forced upward by its motive liuid the massive packer is axially shortened and the bore portion of the mass extrudes inwardly either to engage and seal on a pipe (if interposed) or to so fully compress as to completely choke its bore face. If the compacting ypressure is much sustained it destroys the inherent elastic tendency of the packer to resume its normal, free expanded state in the housing when the piston is forced down to relieve the packer.

To remedy the hazard of loss of expansibility of and in the packer a feature of the instant invention is the provision of a self-acting expander device for the packer il. A very simple, lowcost, practical, durable, eiiicient and self-acting form of the device is here illustrated, inV

its preferred form, as comprising a plurality, of substantially bow-like springs 13 standing endwise and embedded bodily inthe elastic-mass packer 11. The ends of the individual springs are directed inward from the periphery of the packer and are suitably, here, pivotally connected at 13p, to the outer ends of the fingers 10e-l2 respectively. Therefore, when the piston compresses the packer axially the inwardly extruded core portion of the packer drags inward the embedded fingers and these act to pull the outer ends of the springs radially inwardly, putting the arms of the several springs under tension.

When and as the piston is forced down from its upper to its lower, illustrated position in its cylinder the flexed springs will powerfully and inherently pull back the extruded center of the packerrestoring it to the illustrated normal. The springs are permanently affixed in their peripheral arrangement by a substantial anchor ring i5 which is embedded inthe midlength of the packer.

The preferred springs are made of stift spring rod and each is coiled midlength at 13e around the ring 15, and the outer ends of the springs have eyes 13e to make pivotal connection to their armor fingers.

What is claimed is:

1.v A blow out preventer including a housing having an axial, through pipe'hole, =a co-axial, tubular mass of elastic material forming a packer removably slidable into the housing, a co-axial cylinder attached to the housing and having a piston with a ram disc abutting an end of and for Vcompacting the packer, an anchor ring embedded l in the packer and adjacent its periphery and intermediate the ends thereof,l and a circle of inwardly bowed springs medially attached to said ring and extending longitudinally relative -to said packer, said springs being adapted to iiex inwardly when the packer is compacted and vice' versa to restore the packer to its normal expanded position.

2. The preventer of claim l; the ends of lthe springs being contiguous to the top end of the housing and to the said disc.

3. The preventer of claim l; and circular gangs of armor fingers embedded in the ends of the packer to be radially shifted thereby.

4. The preventer of claim l; said springs consisting each of a spring rod coiled at its center around the anchor ring.

5. A blow out preventer, including: atop housing having an axial pipe hole; a tubular mass of elastic packing fitting and free to slide into or from the housing from below; a cylinder 4attached to and coaxial with the housing and having a piston with a ram disc abutting the lower end of the packer to axially compact the packer; resilient means embedded in theV packer to` restore the packer to normal expanded condition when released of piston pressure, said means including aV circular gang of Patented Apr. 29, 1958 d, longitudinal, inwardly bowed springs; and armor ngers pivoted on the ends of the springs and slidable in or out on the upper end of the housing and said disc, respectively.

6. The preventer of claiml; wherein there are-circular gangs-of armor ngers embedded in the ends of the packer to 'be radially shifted thereby, said iingers being connected-to said springs to be retracted thereby to the normal position.

7. The preventer of claim 1 wherein each of said springs comprises a spring rod coiled at its center around the anchor ring, said springs having end eyes to which are pivotally attached armor fingers arranged in upper and lower circularV gangs confined between said disc and the upper end ofthe housing and slidable thereon.

8. A blowout preventer, including: a 'top housing having an axial pipe hole; a tubular mass of elastic packing iitting and free to4 slide into or from the housing from one end; a cylinder attached' to and coaxial with the housing and having a piston with a ram disc abutting one end of the packing to axially compress said packing; and resilient means embedded in the packing and so constructed and arranged as to be compressed axially when ythe packing is axially compressed and to exert force axially to restore the packing to the normal, axially ex- `f panded condition when released of piston pressure.

9. A blowout preventer, including: a top housing having an `axial pipe hole; a tubular mass of elastic packing litting and free to slide into and from the housing from one end; a cylinder attached to and coaxial with the housing and having a piston with a ram disc abutting one end of the packing to axially compress the packing; resilient means embedded in the packing and so constructed and arranged as to be compressed upon axial compression of the packing and to expand axially relative to the packing to restore said packing to the normal axially expanded condition when released of piston pressure; and upper and lower radial armor fingers supported on the ends of the packing to shift inwardly as the packing is compacted and vice versa.

l0. A blowout preventer, including: a top housing having an axial pipe hole; a tubular mass of elastic packing litting and free to slide into and from the housing from one end; a cylinder attached toand coaxial with the housing and'having a piston with a r-arn disc abutting the end of the packing adjacent said housing end to axi- -al'ly compress the packing; resilient means embedded in the packing and so constructedV and arranged as to be compressed upon axial compression of'thefpacking and to expand axially relative to the packing to restore said packing to the normal'axially expanded condition when released of piston pressure; and upper and lower radial housing andhav-ing a piston lwitha ram disc abutting the lower end of the packing to axially compress said packing; and resilient means embedded in the packing and so constructed and arranged as to be compressed axially when the packing is axially compressed and to exert force axially to restore the packing to the normal, axially expanded condition when released of piston pressure, said means including a circular gang of longitudinally extending, inwardly bowed springs, the ends ofwhich flex inwardly when the piston compresses the packing, and vice versa.

t3, A blowout preventcr, including: a top housing having an axial pipe hole; a tubular mass of elastic packing iitting and free to slide into or from the housing from below; a cylinder attached to and coaxial with the he g having a piston with a ram disc abutting the er end of the packing to axially compress said packing; and resilient'me'ans embedded in the packing and so constructed and arranged as to be compressed axially when the packing is axially compressed and to exert force axially to restore the packing to the normal, axialiy expanded condition when released of piston pressure, said means including a circular gang of longitudinally extending, inwardly bowed springs the ends of which are adapted to flex inwardly when the piston compresses the packing, and vice versa, said ends of the springs being contiguous to the top of the housing and to said disc respectively.

armor fingers supported on the ends of the packing to v shift inwardly as the packing is compacted and vice versa, said fingers being separately connected to said means.

ll. A blowout preventer, including: a top housing having an axial pipe hole; a tubular mass of elastic packing fitting and free to slide into and from the housing from below; a cylinder attached to and'coaxial with-the housing and having a piston with a ram disc abutting the lower end of thepacking to axially compress the packing; resilient means embedded in the packingV and so constructed and arranged as to be compressed upon axial compression-of the packing and to expand axially relative 'to the packing to restore said packing to the normal axially expanded condition when released of piston pressure; and upper and lower radial armor ngers supported t on the ends of the packing to shift inwardly as the packing is compacted and vice versa, said fingers being slidable on said discand at the opposite end of an inner face of the housing.

l2. A blowout preventer, including: a top' housing having an axial pipeV hole; a tubular mass of elastic packingl fitting* and# free to slidento or fromV the housing. from below; a-cylinder-att-ached to andicoaxial with'the i4. A blowout preventer, including: a top housing having an axial pipe hole; a tubular mass of elastic packing litting and free to slide into or from the housing from below; a cylinder attached to and coaxial with the housing and having a piston with a ram disc abutting the lower end'of the packing to axially compress said packing; and resilient means embedded in the packing and so constructed and arranged as to be compressed axially when the packing is axially compressed and to exert force axially to restore the packing to the normal, axially expanded condition when released of piston pressure, said means including a circular gang of longitudinally extending, inwardly bowed springs the ends of which are adapted to iiex inwardly when the piston cornpresses the packing, and vice versa, said outer ends of the springs bearing respectively on the top end of the housing and on said disc.

l5. in a packer for blowout preventers: a tubular mass of elastic material; an anchor ring embedded in the tubular mass of material adjacent the periphery, and intermediate the ends thereof; and a circle of inwardly bowed springs medially attached to said ring and extending longitudinally relative to said tubular mass of elastic material, said springs being adapted to flex inwardly when said mass of material is compressed, and vice versa to restore said mass of material to its normal expanded position.

16. ln a packer for blowout preventers: a tubular mass of elastic material; an anchor ring embedded in the tubular mass of material adjacent the periphery, and intermediate the ends thereof; a circle of inwardly bowed springs medially attached to said ring and extending longitudinally relative to said tubular mass of elastic material, said springs being adapted to iiex inwardly when said mass of material is compressed, and vice versa to restore said mass of material to its normal expanded position; and circular gangs of armor lingers embedded in the ends of said tubular mass of elastic material for radially shifting thereby.

l7. In a packer for blowout preventers: a tubular mass of elastic material; an anchor ring embedded in said tubular mass of elastic material adjacent the periphery and intermediate the ends thereof; and a circle of spring rods medially coiled around the anchor ring, said springs extending longitudinally relative to Vsaid tubular mass of material and having the ends thereof bowed inwardly sol as to flex inwardly when the tubular mass of material is compacted and vice versa to restore said material to its normal expanded position.

18. ln an article of manufacture: a tubular mass of elastic packing material; a circular gang of longitudinal, inwardly bowed springs embedded in said packing material; and armor lingers pivoted on the ends of the springs and movable radially.

19. In a packer for blowout preventers: a tubular mass of elastic material; an anchor ring embedded in the tubular mass of material adjacent the periphery, and intermediate the ends thereof; a circle of inwardly bowed springs media'lly attached to said ring and extending longitudinally relative to said tubular mass of elastic material, said springs being adapted to flex inwardly when said mass of material is compressed, and Vice Versa to restore said mass of material to its normal expanded position; and circular gangs of armor fingers at the ends of said mass of material to be radially shifted thereby, said fingers being connected to said springs to be retracted thereby to the normal position.

References Cited in the le of this patent UNITED STATES PATENTS 1,942,366 Seamark Jan. 2, 1934 2,148,844 Stone et al Feb. 28, 1939 2,325,556 Taylor et al. July 27, 1943 2,609,836 Knox Sept. 9, 1952

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