U.S. patent number 3,817,326 [Application Number 05/263,602] was granted by the patent office on 1974-06-18 for ram-type blowout preventer.
This patent grant is currently assigned to Cameron Iron Works, Inc.. Invention is credited to Maurice J. Meynier, III.
United States Patent |
3,817,326 |
Meynier, III |
June 18, 1974 |
**Please see images for:
( Certificate of Correction ) ** |
RAM-TYPE BLOWOUT PREVENTER
Abstract
There is disclosed a ram-type blowout preventer for shearing a
pipe which may be disposed within its bore and then sealing across
the bore.
Inventors: |
Meynier, III; Maurice J.
(Houston, TX) |
Assignee: |
Cameron Iron Works, Inc.
(Houston, TX)
|
Family
ID: |
23002469 |
Appl.
No.: |
05/263,602 |
Filed: |
June 16, 1972 |
Current U.S.
Class: |
166/55;
251/1.3 |
Current CPC
Class: |
E21B
33/063 (20130101); E21B 29/08 (20130101) |
Current International
Class: |
E21B
33/06 (20060101); E21B 29/08 (20060101); E21B
29/00 (20060101); E21B 33/03 (20060101); E21b
029/00 () |
Field of
Search: |
;251/1,67
;166/55,55.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Brown; David H.
Attorney, Agent or Firm: Hyer; W. F. Eickenroht; Marvin
B.
Claims
The invention having been described, what is claimed is:
1. A blowout preventer, comprising a housing having a bore
therethrough and a pair of guideways therein extending laterally
from the bore, and a ram including a body movable axially within
each guideway between an outer position removed from the bore and
an inner position across the bore; each ram body having inner and
outer ends, a cutting edge extending across its inner end, a
surface extending outwardly from said edge, and a wall extending
from the outer end of the surface to the outside of the ram so as
to provide a recess, said surfaces facing in opposite directions so
that the cutting edge of each ram body moves closely past the
cutting edge and over the surface of the other ram body, so as to
shear a pipe disposed within the bore, as the rams move to their
inner positions; seal means including a seal member on and
extending across the surface of one ram body for disposal opposite
the surface of said other ram body, and portions carried by the ram
bodies for sealing between one ram body and the other on opposite
ends of said seal member and for sealing between each ram body and
its guideway so as to seal off the bore of said housing, when the
ram bodies are moved to their inner positions, the inner end of
each ram body being spaced from the wall of the other ram body,
when said ram bodies are in their inner positions, to permit a cut
end of the pipe to be received in the recess between them.
2. A blowout preventer of the character defined in claim 1, wherein
said seal means includes faces abuttable with one another to deform
said seal means and seal member into sealing engagement, during
movement of said rams to their inner positions.
3. A blowout preventer of the character defined in claim 2, wherein
said seal means includes rigid parts on their sides past which the
body of a ram moves following abutment of the faces of said seal
means.
4. A blowout preventer of the character defined in claim 1, wherein
each ram body has flanges extending from its inner end to provide
surfaces which face oppositely to surfaces on said body on opposite
sides of said outwardly extending surface, and the portions of the
seal means of each ram comprise side seal parts disposed between
said oppositely facing surfaces and engaging the guideways and the
opposite ends of said seal member.
5. A blowout preventer of the character defined in claim 4, wherein
the side seal parts on one ram have front faces abutable with those
of the other ram to deform said seal means and seal member into
sealing engagement during movement of said rams to their inner
positions.
6. For use with a blowout preventer having a housing with a bore
therethrough and a pair of guideways extending laterally from the
bore, apparatus comprising a pair of rams each including a body
having inner and outer ends and adapted to slide within one of the
guideways between an outer position removed from the bore and an
inner position across the bore, each body having a cutting edge
extending across its inner end, a surface extending outwardly from
said edge, and a wall extending from the outer end of said surface
to the outside of the ram body to provide a recess, the distance
between the surface and the top of one ram body being substantially
equal to that of the other ram body, and the distances from the
cutting edge of each ram body to said wall being such that, when
the rams are mounted in the guideways with their surfaces facing in
opposite directions and moved into their inner positions, their
cutting edges will move closely past one another and over said
surfaces, so as to shear a pipe disposed within the bore, and the
inner end of each body will be so spaced from the wall of the other
body that a cut end of the pipe may be received in the recess
therebetween, seal means including a seal member on and extending
across the surface of one ram body for disposal opposite the
surface of the other ram body, and portions carried by each ram
body for sealing between it and the other ram body on opposite ends
of the seal member and between each body and its guideway so as to
seal off the bore of said housing when the ram bodies are moved to
their inner positions.
7. Apparatus of the character defined in claim 6, wherein said seal
means includes front faces on one ram abuttable with those on the
other to deform said seal means into sealing engagement during
movement of said rams to their inner positions.
8. Apparatus of the character defined in claim 7, wherein said seal
means includes rigid parts on their inner sides past which the body
of the other ram moves following abutment of the faces of said seal
means.
9. Apparatus of the character defined in claim 6, wherein each ram
body has flanges extending from its inner end to provide surfaces
which face oppositely to surfaces on said body on opposite sides of
said outwardly extending surface, and the portions of the seal
means of each ram comprise side seal parts disposed between said
oppositely facing surfaces and engaging the guideways and the
opposite ends of said seal member.
10. Apparatus of the character defined in claim 9, wherein the side
seal parts on one member have front faces abutable with those of
the other ram to deform said seal means into sealing engagement
during movement of said rams to their inner positions.
11. A blowout preventer ram, comprising a body having inner and
outer ends and a top and bottom adapted to slide axially within a
guideway of a blowout preventer housing, a cutting edge extending
laterally across its inner end, a surface extending outwardly from
the cutting edge intermediate the top and bottom, and a wall
extending from the outer end of said surface to the top of the ram
body to provide a recess for receiving a cut pipe end, and seal
means carried by the ram body including portions extending along
one side of the recess, over the top of the ram body outwardly of
the recess, and along the opposite side of the recess, said seal
means also including rigid plates extending forwardly from the wall
of the inner side on the seal means along opposite sides of the
recess.
12. A blowout preventer ram, comprising a carrier having inner and
outer ends, a top and bottom, and opposite sides, a lower
horizontal portion extending outwardly from its inner end and
laterally from one side to the other of the carrier; a vertical
wall extending upwardly from the outer end of the horizontal
portion to the top, and a flange extending inwardly from the
vertical wall at each side of the top of the carrier, so as to
provide upper horizontal surfaces above lower horizontal surfaces
of said lower horizontal portion at opposite sides of the carrier;
a blade removably mounted on the lower horizontal portion of the
carrier and having a cutting edge across its inner end extending
inwardly of the carrier, a top surface extending outwardly of said
cutting edge intermediate said flanges and horizontal portion, and
having sides; and seal means mounted on the carrier, including a
side seal part on each side of the blade each having a side
adjacent a side of the blade, a side forming a substantial
continuation of the adjacent side of the carrier, a top and bottom
adjacent the upper and lower horizontal surfaces, respectively, an
outer end adjacent the vertical wall of the carrier, and an inner
end protruding from the carrier; a seal disposed between the blade
and carrier and extending from one side seal part to the other; and
a top seal part extending across the top of the carrier and
engaging at opposite ends with the side seal parts.
13. A ram of the character defined in claim 12, wherein each side
seal part comprises a body of deformable material having rigid
plates on the top and bottom thereof which extend outwardly from
its inner end for less than its length, and an additional rigid
plate on an outer upper portion of its inward side which extends
downwardly from its top less than its height but beneath the level
of the top surface of the blade.
14. A blowout preventer ram, comprising a body having inner and
outer ends and a top and bottom adapted to slide axially within the
guideway of a blowout preventer housing, said body including a
carrier and a blade removably mounted on the carrier, a cutting
edge on the blade extending across its inner end, a surface on the
blade extending outwardly from the cutting edge intermediate the
top and bottom of the body, and a wall extending from the outer end
of said surface to the bottom of the ram body to provide a recess,
and seal means carried by the body including portions extending
along one side of the recess, over the top of the ram body
outwardly of the recess, and along the opposite side of the recess,
and a first seal member on the blade extending continuously across
said surface from one side to the other to engage the seal means
along the opposite sides of said recess, said seal means including
a second seal member extending between the carrier and blade to
engage the seal means along the opposite sides of said recess.
15. A blowout preventer ram, comprising a carrier having inner and
outer ends, a top and bottom, and opposite sides, an upper
horizontal portion extending outwardly from its inner end and
laterally from one side to the other of the carrier, a vertical
wall extending downwardly from the outer end of the horizontal
portion to the bottom of the carrier, and a flange extending
inwardly from the vertical wall at each side of the bottom of the
carrier, so as to provide lower horizontal surfaces below upper
horizontal surfaces of said upper horizontal portion at opposite
sides of the carrier; a blade removably mounted on the upper
horizontal portion of the carrier and having a cutting edge across
its inner end extending inwardly of the carrier, a lower surface
extending outwardly of said cutting edge intermediate said flanges
and horizontal portion and sides between the upper and lower
horizontal surfaces; and seal means mounted on the carrier,
including side seal parts each having a side adjacent a side of the
blade, a side forming a substantial continuation of the adjacent
side of the carrier, a top and bottom adjacent the upper and lower
horizontal surfaces, respectively, an outer end adjacent the
vertical wall of the carrier, and an inner end protruding from
adjacent portions of the inner end of the carrier; a seal disposed
between the blade and carrier and extending from one side seal part
to the other, a top seal part extending across the top of the
carrier and engaging at opposite ends with the side seal parts, and
a seal member carried on and extending across the lower surface of
the blade and engaging at opposite ends with the side seal
parts.
16. A blowout preventer ram of the character defined in claim 15,
wherein each side seal part comprises a body of deformable material
having rigid plates on the top and bottom thereof, which extend
rearwardly from its inner end for less than its length, and an
additional rigid plate on an outer lower portion of its inward side
which extends upwardly from its bottom less than its height but
above the level of the bottom 7 surface of the blade.
17. For use in a blowout preventer, having a housing, a bore
through the housing, ram guideways extending from the bore, and
means for moving rams inwardly and outwardly, a ram, comprising a
body having shearing means on its inner end, including a cutting
edge and a surface extending outwardly from the cutting edge for
cooperation with the shearing means of an opposing ram as said rams
are moved inwardly, and means on the body for sealing between the
body and a guideway and with an opposing ram, said sealing means
including a seal member in said surface extending along but spaced
outwardly of said cutting edge.
18. For use in a blowout preventer, having a housing, a bore
through the housing, ram guideways extending from the bore and
means for moving rams inwardly and outwardly, a ram, comprising a
body having shearing means on its inner end, including a cutting
edge and a surface extending outwardly from the cutting edge for
cooperation with shearing means of an opposing ram upon movement of
said rams inwardly, means on the body for sealing between the body
and a guideway with an opposing ram, said means for sealing with an
opposing ram including a seal member substantially flush with said
surface and extending laterally across it.
19. A ram of the character defined in claim 18, wherein said ram
body has a recess between said surface and the outside of the body
for receiving material that has been sheared.
20. A blowout preventer, comprising a housing having a bore
therethrough and a pair of guideways therein extending laterally
from the bore, and a ram including a body movable axially within
each guideway between an outer position removed from the bore and
an inner position across the bore, each ram body having inner and
outer ends, a cutting edge extending across its inner end and a
surface extending outwardly from said edge, said surfaces facing in
opposite directions so that the cutting edge of each ram body moves
closely past the cutting edge and over the surface of the other ram
body, so as to shear a pipe disposed within the bore, as the rams
move to their inner positions, and seal means carried by the ram
bodies including a seal member carried on and extending across the
surface of one ram body for disposal opposite the surface of said
other ram body, and portions for sealing between one ram body and
the other on opposite ends of said seal member and for sealing
between each ram body and its guideway so as to seal off the bore
of said housing, when the ram bodies are movd to their inner
positions.
21. For use with a blowout preventer having a housing with a bore
therethrough and a pair of guideways extending laterally from the
bore, apparatus comprising a pair of rams each including a body
having inner and outer ends and adapted to slide within one of the
guideways between an outer position removed from the bore and an
inner position across the bore, each body having a cutting edge
extending across its inner end and a surface extending outwardly
from said edge, said rams being mountable in the guideways with
their surfaces facing in opposite directions so that, when moved
into their inner positions, their cutting edges will move closely
past one another and over said surfaces, so as to shear a pipe
disposed within the bore, and seal means including a seal member
carried on and extending across the surface of one ram body for
disposal opposite the surface of the other ram body, and portions
carried by each ram body for sealing between it and the other ram
body on opposite ends of the seal member and between each body and
its guideway so as to seal off the bore of said housing when the
ram bodies are moved to their inner positions.
22. A blowout preventer, comprising a housing having a bore
therethrough and a pair of guideways therein extending laterally
from the bore, and a ram including a body movable axially within
each guideway between an outer position removed from the bore and
an inner position across the bore, each ram body having inner and
outer ends, a cutting edge extending across its inner end, and a
surface extending outwardly from said edge, said surfaces facing in
opposite directions so that the cutting edge of each ram body moves
closely past the cutting edge and over the surface of the other ram
body, so as to shear a pipe disposed within the bore, as the rams
move to their inner positions, and seal means carried by the ram
bodies including a seal member carried on and extending across the
surface of one ram body for disposal opposite the surface of said
other ram body and portions for sealing between one ram body and
the other on opposite ends of said seal member and for sealing
between each ram body and its guideway so as to seal off the bore
of said housing, when the ram bodies are moved to their inner
positions, each said ram body having a recess between its surface
and the outside of the body for receiving a cut end of the
pipe.
23. For use with a blowout preventer having a housing with a bore
therethrough and a pair of guideways extending laterally from the
bore, apparatus comprising a pair of rams each including a body
having inner and outer ends and adapted to slide within one of the
guideways between an outer position removed from the bore and an
inner position across the bore, each body having a cutting edge
extending across its inner end and a surface extending outwardly
from said edge, said rams being mountable in the guideways with
their surfaces facing in opposite directions so that, when moved
into their inner positions, their cutting edges will move closely
past one another and over said surfaces, so as to shear a pipe
disposed within the bore, and seal means including a seal member
carried on and extending across the surface of one ram body for
disposal opposite the surface of the other ram body and portions
carried by each ram body for sealing between it and the other ram
body on opposite ends of the seal member and between each body and
its guideway so as to seal off the bore of said housing when the
ram bodies are moved to their inner positions, each said ram body
having a recess between its surface and the outside of the body for
receiving a cut end of the pipe.
24. In a blowout preventer having a housing containing a pair of
rams having shearing edges adapted to shear pipe extending through
the housing as the rams are moved to closed position, the
improvement which comprises, in combination therewith, each ram
having a horizontal surface extending outwardly of its shearing
edge to a wall; the wall of each ram being spaced outwardly of the
shearing edge of the other ram sufficiently to provide a recess
therebetween of sufficient size to receive a cut end of the pipe
when the rams are in closed position to avoid having to move either
end of the pipe vertically in order to permit the rams to move to
fully closed position; and seal means for sealing between the rams
and between each ram and the housing including a first groove in
one ram formed in the horizontal surface thereof along but spaced
from its shearing edge so as to be substantially closed by the
other ram surface when the rams are in closed position, a second
groove in the periphery of each ram adapted to be substantially
closed by the housing when the rams are in closed position, the
second groove in said one ram communicating with the first groove
therein; and resilient seal material in said grooves, said seal
means including means to deform the sealing material into sealing
engagement with said other ram surface and said housing during
closing of the rams.
25. For use in a blowout preventer to shear a pipe extending
through the housing thereof and then to seal off a well, apparatus
comprising a pair of blind rams each having a shearing edge adapted
to so shear a pipe when the rams are moved to closed position and
each having a horizontal surface extending outwardly of its
shearing edge to a wall; the wall of each ram being spaced
outwardly of the shearing edge of the other ram sufficiently to
provide a recess therebetween for receiving a cut end of the pipe
when the rams are in closed position to avoid having to move either
end of the pipe vertically in order to permit the rams to move to
fully closed position; and seal means for sealing between the rams
and for sealing between each ram and the housing when the rams are
mounted therein including a first groove in one ram formed in the
horizontal surface thereof along but spaced from its shearing edge
so as to be substantially closed by the other ram surface when the
rams are in closed position, a second groove in the periphery of
each ram adapted to be substantially closed by the housing when the
rams are in closed position, the second groove in said one ram
communicating with the first groove therein; and resilient seal
material in said grooves, said seal means including means to deform
the sealing material into sealing engagement with said other ram
surface and said housing during closing of the rams.
26. A blowout preventer having shear rams for severing a tubular
member extending through the bore thereof and then sealing the
bore, characterized in that a seal member is imbedded in a
horizontal surface extending across one ram and is adapted to seal
against a complimentary horizontal surface of the other ram when
the rams are in closed position.
27. A blowout preventer having a pair of shear rams adapted to be
moved in an axial direction in the guideways of the blowout
preventer to sever a member extending through the bore of the
blowout preventer and then seal the bore, characterized in that one
ram has a surface extending in said axial direction and terminating
in a cutting edge and including a seal member substantially flush
with said surface, said surface and seal member extending
substantially across said one ram and being adapted to seal against
a complementary surface of the other ram when the rams are in
closed position.
28. A shear ram adapted to be moved in an axial direction in a
guideway of a blowout preventer to cooperate with another shear ram
to sever a member extending through the bore of the blowout
preventer and then seal the bore, characterized in that a surface
of the ram extends in said axial direction and terminates in a
cutting edge and includes a seal member substantially flush with
said surface, said surface and seal member extending substantially
across the ram and being adapted to seal against a complementary
surface of the other ram when the rams are in closed position.
29. A shear ram adapted to be moved in an axial direction in a
guideway of a blowout preventer to cooperate with another shear ram
to sever a member extending through the bore of the blowout
preventer and then seal the bore, characterized in that a surface
of the ram extends in said axial direction and terminates in a
cutting edge and includes means adapted to mount a seal member
substantially flush with said surface, said surface and seal member
when so mounted extending substantially across the ram and being
adapted to seal against a complementary surface of the other ram
when the rams are in closed position.
Description
This invention relates generally to ram-type blowout preventers;
and, more particularly, to the type of blowout preventer having
means on the rams for shearing a pipe which may be disposed within
its bore and then sealing across the bore.
As well known in the art, a ram-type blowout preventer comprises a
housing having a bore through it and adapted to be connected to a
wellhead in alignment with the well bore. Rams are movable within
guideways extending from the bore between outer positions removed
from the bore and inner positions across the bore and engaging with
one another to seal off the bore. The inner ends of the rams may
have recesses for sealing about a pipe within the bore, or they may
be flat or otherwise complementary for sealing across an open
bore.
In the drilling of offshore wells from vessels at the water level,
the preventer may be mounted on a wellhead located a considerable
distance below water level. In the event of a storm or other
emergency condition, it may be desirable to move the vessel from
the well site, and circumstances may not permit the drill string to
be pulled from the well. In order to meet this and other
eventualities, it has been proposed to provide rams with blades
having cutting edges for shearing the pipe as the rams move to
their inner positions, and with seal means so arranged as to seal
between the rams and between each ram and the preventer housing to
close the bore upon shearing of the pipe.
One such preventer is shown in U.S. Pat. No. 3,561,526, assigned to
the assignee of the present improvement. Some concern has been
expressed by users as to whether or not a perfect seal could be
attained if the cut ends of the pipe or other junk remain between
the rams after shearing. It is therefore an object of this
invention to overcome that problem by providing a blowout preventer
of this type in which the rams will seal with respect to one
another, and thus permit the bore of the preventer to be closed
off, even though such junk may be disposed between them.
Another object is to provide a blowout preventer of the type above
described in which the seal means of each ram is protected against
damage by the sheared pipe as the rams are moved inwardly to shear
the pipe and close off the bore.
A further object of the present invention is to provide a blowout
preventer of the type above described in which, as in the
aforementioned prior patent, the rams seal entirely across their
widths.
These and other objects are accomplished, in accordance with the
illustrated embodiment of the present invention, by a ram-type
preventer in which, as in prior preventers for use in shearing a
pipe within the bore through the housing thereof, each ram
comprises a body having shearing means including a cutting edge
across its inner end and a surface extending outwardly of the
cutting edge. More particularly, the ram bodies are arranged in the
guideways of the housing for movement in an axial direction with
these surfaces facing in opposite directions in generally the same
plane so that the cutting edge of each body moves closely past the
cutting edge and over the surface of the other body to shear a pipe
within the bore as the rams move to their inner positions.
However, as distinguished from the rams of prior preventers of this
type, a seal member is carried by one of the ram bodies on and
across the width of its surface and substantially flush therewith
for disposal opposite the surface of the other ram body, and thus
for sealing between said surfaces, when the rams have been so
moved. More particularly, this seal member is cooperable with
additional seal means portions carried by the ram bodies for
sealing between the ram bodies at opposite ends of said seal member
and between each ram body and its guideway, so as to seal off the
bore of the housing when the ram bodies are moved to their inner
positions. Also, the surfaces on the ram bodies are of such outward
extent as to provide space for the cut ends of the pipes when the
rams have been moved to their inner positions, and thus permit the
ram bodies to move to their inner positions to seal off the bore of
the housing upon shearing of the pipe therein. More particularly,
each surface extends outwardly to a wall which extends from the
outer end of the surface to the outside, that is the top or bottom
of the ram body, to provide a recess for receiving a cut end of the
pipe between the inner end of one ram body and the wall of the
other ram body.
In accordance with the preferred embodiment of the invention, said
seal means includes faces abuttable with one another so as to
deform the seal means and seal member into sealing engagement as
said ram bodies move into their inner positions. The seal means
also includes parts on their inner sides past which the other ram
moves, following abutment of the faces of said seal means, to
protect deformable material of the seal means against damage by the
ram bodies.
As illustrated, each ram body has flanges which extend from its
inner end to provide surfaces which face oppositely to surfaces on
said body on opposite sides of the outwardly extending surfaces on
the body, and said seal means comprise side seal parts disposed
between said oppositely facing surfaces on the body to engage on
their sides with the guideways and with opposite ends of the seal
member carried by one of the ram bodies .
In the drawings, wherein like reference characters are used
throughout to designate like parts:
FIG. 1 is a side view, partly in section and partly in elevation,
of a blowout preventer constructed in accordance with the present
invention, and with the rams thereof in their outer positions;
FIG. 2 is a view similar to FIG. 1, but with the rams moved to
their inner positions to shear a pipe in the bore of the preventer
and seal off the bore;
FIG. 3 is an isometric view of the rams removed from the guideways
in the preventer housing;
FIG. 4 is an exploded view of the right-hand ram, as seen from the
top and one side thereof;
FIG. 5 is an exploded view of the left-hand ram, as seen from the
bottom and one side thereof;
FIG. 6 is a top view of the rams within the guideways, and moved to
their inner positions, as seen along section line 6--6 of FIG.
2;
FIG. 7 is a vertical cross-sectional view of the rams, as seen
along section broken line 7--7 of FIG. 6; and
FIG. 8 is a horizontal sectional view of the rams of FIG. 7, as
seen along section broken line 8--8 of FIG. 7.
With reference now to the details of the above-described drawings,
the over-all preventer 10 is shown in FIGS. 1 and 2 to comprise a
housing 11 having a bore 12 therethrough and a pair of rams 13A and
13B movable axially within guideways 14 extending laterally from
opposite sides of the bore. The lower end of the housing is adapted
to be connected to a wellhead in axial alignment with the bore of
an underwater well, which may be disposed a substantial distance
beneath the water level. The rams are shown in FIG. 1 in their
outer positions, wherein they are removed from the bore 12 of the
housing to permit a drill pipe 15 to extend therethrough and thus
into the well bore.
The rams are caused to move between the outer position of FIG. 1
and the inner position of FIG. 2 by means of operators 16 connected
to the housing at the outer ends of the ram guideways 14. These
operators include reciprocating hydraulic actuators releasably
connected to the outer ends of the rams, as by means of "T" slots,
as well known in the art. Reference may be had, for example, to
U.S. Pat. No. 3,272,222 for a detailed description of the
construction and function of operators 16, including their
releasable connection to the preventer housing to permit
installation and removal of the rams. As will be described below,
when moved to their inner positions, the rams shear pipe 15 and
then seal off the bore so as to contain well fluid therebelow.
As best shown in FIGS. 3 and 4, ram 13A comprises a body 17A
consisting of a carrier 18A and a shear blade 19A removably mounted
thereon. The carrier has inner and outer ends, and a top and bottom
and opposite sides which slide axially within its guideway in
response to operation of the operator 16 connected to its outer
end. As shown, the opposite sides of the carrier are curved for
fitting closely within its guideway. The bottom of the carrier 18A
includes a flange 20A which extends entirely across its inner end
to provide an upwardly facing surface on which the blade 19A is
mounted. When so mounted, the blade is releasably secured to the
carrier by means of bolts extending through aligned holes in the
flange and bottom side of the blade.
The inner end of blade 19A projects beyond the inner end of flange
20A and has a cutting edge 22A which is of a wide "V" shape for
cooperation with a similarly shaped cutting edge on the blade of
the other ram 13B, as will be described below. With the blade
mounted on the carrier, its top surface 23A is disposed in a plane
perpendicular to the axis of the bore 12 and equidistant from the
top and bottom of the carrier. The blade 19A is not as wide, from
side to side, as the flange 20A, so that when it is mounted on the
carrier, its opposite sides are spaced from the opposite sides of
the carrier.
A wall 21A extends vertically upwardly from the rear end of the
upwardly facing surface provided by the flange 20A to intersect the
top of the carrier intermediate its inner and outer ends, and the
space above this surface is unobstructed to provide a recess to
receive the blade of the other ram and the upper cut end of a pipe.
A pair of flanges 24A extend forwardly from the upper, outer
corners of wall 21A to provide surfaces which are axially
coextensive with and which are parallel and face oppositely to the
opposite ends of the upwardly facing surface of flange 20A. More
particularly, these downwardly facing surfaces on flanges 24A are
spaced above the upwardly facing surfaces of the flange 20A a
distance approximately twice the thickness of the blade 19A so as
to permit a blade of the same thickness on the left-hand ram 13B to
be moved into the space between the top of blade 19A and the
flanges 24A, as will be described below.
The seal means mounted on the carrier 18A includes side seal parts
25A and 26A adapted to be mounted on the sides of the carrier, each
between a flange 24A and the oppositely facing surface of flange
20A. The outer sides of the side seal parts are curved to form
continuations of the curved sides of the ram body carrier for
sliding within a guideway 14, and the inner sides of such parts
face the opposite sides of the recess.
The side seal parts 25A and 26A abut the vertical wall 21A, and
protrude inwardly beyond flanges 24A and 20A. Thus, they provide
vertical faces 27A and 28A, respectively adapted to abut similar
faces on ram 13B, as will also be described below.
The seal means mounted on carrier 18A also includes a top seal part
29A which is substantially U-shaped and adapted to fit closely
within a similarly shaped groove 30A formed over the top and along
the opposite sides of the ram body carrier 18A. The opposite ends
of the top seal part 29A are notched at 31A so as to fit closely
adjacent the upper rear corners of the side seal parts 25A and 26A
to provide a continuous sealing surface over the top of the ram and
along its opposite sides to its inner end. Top seal part 29A is
curved so as to form substantially a continuation of the top and
sides of the ram carrier 18A.
It will be understood that these parts of the seal means of ram 13A
are similar in construction and function to corresponding portions
of the rams of the preventer of the aforementioned U.S. Pat. No.
3,272,222. That is, as will be apparent from FIGS. 1 and 2, the top
seal part 29A and side seal parts 25A and 26A are confined by the
guideway 14 in both the inner and outer positions of the ram.
Consequently, with the ram in its inner position, these seal parts
will, upon deformation in response to engagement with the other ram
13B, provide a continuous seal between the ram and guideways across
its top and along its sides.
The opposite ends of the top seal part are provided with pins 32A
which are adapted to fit within holes 33A formed in the groove 30A
near its opposite ends. Also, a pin 34A extends from the rear end
of each side seal part 25A and 26A for fitting within a hole 35A
formed in the wall 21A of the carrier near its opposite sides. The
holes 33A and 35A on opposite sides of the carrier intersect, and
the other ends of the pins 34A are grooved so that with the side
seal parts first mounted on the carrier, the top seal part 29A may
be moved into position to cause the lower ends of its pins 32A to
engage in the grooved portions of the side seal part pin 34A, as
shown in FIG. 8, and thus lock the side seal parts in place on the
carrier.
The outer bottom corner of blade 19A is grooved at 36A to receive a
seal part 37A of deformable material for extension across the width
of the blade so as to dispose its opposite ends adjacent the inner
sides of the side seal parts 25A and 26A. Thus, when the seal part
37A is deformed by deformation of the side seal parts, it prevents
well fluid from by-passing the blade.
As best shown in FIG. 4, each side seal part comprises a body of
deformable sealing material having thin rigid plates 38A, 39A and
40A molded to its top, bottom and inner sides, respectively. Each
of the top and bottom plates extends lengthwise of each side seal
part from its front end for less than its entire length, and each
inner plate 40A extends vertically from the top of each side seal
part for less than its height and from its rear end longitudinally
for less than its length. Top plate 38A has a rearwardly extending
leg which is spaced from and along the outer side of side plate
40A, and the side plate has an outwardly extending flange at its
outer end which is spaced from and rearward of the rear end of the
leg of the top plate. These flanges on the outwardly extending
flanges on the side plate 40A support the pins 34A. The inner ends
of plates 38A and 39A extend across most of the width of the side
seal parts, and thus prevent the deformable sealing material
thereof from being extruded between adjacent faces of the
carriers.
The lower edge of each inner plate 40A extends below the top
surface 23A of blade 19A, and a leg 41A extends downwardly from the
lower surface of each flange 24A to provide a surface closely
adjacent the upper rear corner of the plate 40A, which surface
cooperates with shear blade 19A to prevent plate 40A from being
pushed into the space in which the blade of the other ram is to be
received.
As best shown in FIGS. 3 and 5, ram 13B is quite similar to ram
13A, in that it comprises a body 17B consisting of a shear blade
19B removably mounted on a carrier 18B. Also, the carrier 18B has
inner and outer ends, and a top and bottom and opposite sides which
are caused to slide axially within a guideway by an operator
mounted across the outer end of the guideway. The carrier has a
flange 20B extending across its inner end to provide a surface on
which the blade is mounted, and a vertical wall 21B at the outer
end of the surface on the flange to provide a recess for receiving
the blade 19A of ram 13A and the lower cut end of a pipe. However,
when the ram 13B is assembled in its guideway 14, these parts are
reversed top for bottom with respect to the corresponding parts of
ram 13A. Thus, flange 20B extends inwardly from the top of carrier
18B to provide a downwardly facing flat surface to which the top
side of blade 19B is secured by bolts which extend through aligned
holes in flange 20B and top side of plate 19B. Also, wall 21B
extends downwardly to intersect the bottom of the carrier
intermediate its inner and outer ends.
The blade 19B has a "V" shaped cutting edge 22B and projects
forwardly of the inner end of the carrier to provide a surface 23B
- in this case downwardly facing - which is disposed in a plane
perpendicular to the axis of bore 12. More particularly, blade 19B
is of the same size as blade 19A, and its surface 23B is
approximately equidistant from the top and bottom of the carrier.
Thus, as will be more fully understood from the description to
follow, when the rams 13A and 13B are mounted in their guideways,
the top and bottom surfaces, respectively, of their blades are
disposed in substantially the same plane, so that during movement
of the rams to their inner positions, the cutting edges of each
will shear the pipe 15 by moving past one another and over the
surface of the other.
As in the case of blade 19A of ram 13A, the opposite sides of blade
19B are spaced inwardly from the opposite sides of carrier 18B.
Also, the space below the bottom surface 23B of the blade is
unobstructed, except for a pair of flanges 24B which extend
forwardly from the lower, outer corners of wall 21B. The tops of
these flanges provide surfaces which are axially coextensive with
and which are parallel and face oppositely to the opposite
downwardly facing surfaces at the sides of the flange 20B. Flanges
24B are spaced below the surfaces of flange 20B a distance
approximately twice the thickness of plate 19B so as to permit
blade 19A to be moved into the space between blade 19B and flanges
24B, as blade 19B simultaneously moves into the space between blade
19A and flanges 24A of ram 13A.
More particularly, the shear blades are of such length end-for-end
that, when moved to their inner positions, they will overlap for a
considerable axial distance, so as to dispose a seal member 42
carried on and extending across surface 23B of blade 19B opposite
the upwardly facing surface 23A of blade 19A, and at the same time
leave a substantial space between the inner end of each ram and the
vertical wall of the other ram to receive the cut ends of the pipe.
As best shown in FIG. 5, seal member 42 is somewhat enlarged across
its top and is slidable into and out of a groove 43 of conforming
cross section. When in the groove, it provides a lower surface
which forms a continuation of surface 23B so that it will move
freely over surface 23A as the rams are moved into and out of their
inner positions. However, when the rams are moved into their inner
positions, the seal member is deformed to cause its lower surface
to protrude and thus sealingly engage blades 19A and 19B across
their entire widths. The lower edges of seal member 42 are retained
against extrusion by means of imbedded elongate coil springs
44.
In other respects, the construction and function of ram 13B will be
understood from the foregoing description of ram 13A, and hence
corresponding parts have been given corresponding reference
characters, with those of rams 13B using the letter "B" rather than
the letter "A".
Thus, as best illustrated in FIG. 6, the protruding faces 27A and
27B, as well as 28A and 28B, of the seal means of the rams abut one
another only after shearing of the pipe 15 and movement of the
blades into an overlapping position in which the seal member 42 is
opposite the surface 23A of the blade 19A of the ram 13A, but
before final movement of the rams into their inner positions. Upon
continued inward movement of the rams, the abutting faces are
forced against one another to deform the deformable sealing
material of the side seal parts, which deformation is in turn
transmitted to top seal parts 29A and 29B, to seal parts 37 and 38,
and to seal member 42. Consequently, when the rams have been moved
to their inner positions, all such portions have been deformed to
provide a continuous seal between one ram and the other as well as
between each ram and its guideway so as to seal off the upper end
of the bore 12.
This continuous seal includes the sealing engagement of the inner
side of each side seal part of each ram with the side of the blade
of the other ram. However, as will be apparent from FIGS. 6 and 7,
the side plates 40A and 40B on the side seal parts of the two rams
are of such axial length that the shear blades move past the front
edges of such plates prior to abutment of the side seal parts with
one another, and thus prior to deformation of the deformable
sealing material. Consequently, the shear blades are prevented from
damaging the side seal parts during continued movement of the rams
in an inward direction.
Thus, as indicated above and as shown in the drawings, seal member
42 is substantially flush with surface 23B and is adapted to seal
against surface 23A (the latter being complementary to surface 23B)
when the rams are in closed position. Also, the groove 43 can be
termed a means adapted to mount seal member 42 substantially flush
with surface 23B. Further, surface 23A can be said to extend in an
axial direction and to terminate in cutting edge 22B.
Although it is preferred that the surfaces 23A and 23B of the rams
13A and 13B, respectively, be flat and disposed in planes
perpendicular to the axis of the bore 12 of the preventer housing,
it is contemplated that such surfaces may instead be other than
perpendicular to the axis of the bore of the preventer housing, and
even curved as long as all straight line elements on the surface
are parallel to the axis of the ram. In any event, however, the
surfaces extend across the rams for a sufficient extent to provide
cutting edges which cooperate with one another in shearing the pipe
in the bore.
Also, although it is preferred that the shear blades be removable
from the ram carriers, they may instead be made integral therewith.
Still further, the seal member 42 could instead be mounted on the
upwardly facing surface of the ram 13A; and, in fact, two such seal
members may be provided, one on each such surface and positioned
either to engage one another or engage axially spaced-apart
portions of the surfaces opposite to which they are disposed.
From the foregoing it will be seen that this invention is one well
adapted to attain all of the ends and objects hereinabove set
forth, together with other advantages which are obvious and which
are inherent to the apparatus.
It will be understood that certain features and subcombinations are
of utility and may be employed without reference to other features
and subcombinations. This is contemplated by and is within the
scope of the claims.
As many possible embodiments may be made of the invention without
departing from the scope thereof, it is to be understood that all
matter herein set forth or shown in the accompanying drawings is to
be interpreted as illustrative and not in a limiting sense.
* * * * *