METHODE DE CIRCULATION PAR POMPE ALTERNATIVE DE FOND ET POMPE ALTERNATIVE DE FOND

A METHOD OF CIRCULATING THROUGH A RECIPROCATING DOWNHOLE TUBING PUMP AND A RECIPROCATING DOWNHOLE TUBING PUMP

Abrégé français

Méthode de circulation par pompe alternative de fond et pompe alternative de fond connexe. La pompe alternative de fond comporte un ensemble de clapet fixe et un clapet de refoulement. La méthode comprend le déplacement et l'invalidation - sans les retirer - de l'ensemble de clapet fixe et du clapet de refoulement. Cela peut se faire à l'aide de tiges qui neutralisent les billes en les mettant hors position ou en emprisonnant les billes dans des cages qui peuvent être mises hors position mécaniquement à l'aide de liens. Une fois l'ensemble de clapet fixe et le clapet de refoulement invalidés, la circulation peut se faire dans la pompe alternative de fond. Cela comporte un certain nombre d'avantages, comme le retrait des blocages attribuables à l'accumulation de sable.

Abrégé anglais

A method of circulating through a reciprocating downhole tubing pump and a reciprocating downhole tubing pump. The reciprocating downhole tubing pump has a standing valve assembly and a travelling valve. The method involves displacing and disabling, without removing, the standing ball valve assembly and the travelling valve. This can be done with pins which knock the balls out of position or by enclosing the balls in cages which can be mechanically moved out of position with linkages. With the standing ball valve assembly and the travelling valve disabled, circulation can occur through the reciprocating downhole tubing pump. This has a number of advantages, such as removal of blockages due to sand accumulation.

Revendications

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WHAT IS CLAIMED IS:
1. A method of circulating through a reciprocating downhole
tubing pump which has a standing ball valve and a travelling
ball valve positioned downhole, comprising the steps of:
providing a standing ball valve assembly that has:
an upstanding first pin secured on top of the
standing ball valve assembly, the first pin being in axial
alignment with a first ball seat which receives a first ball
on the travelling ball valve;
a second ball seat which receives a second ball,
the second ball being confined within a ball cage;
a pivot linkage adapted to pivot the ball cage from
an operative position to a circulating position in which the
ball cage is raised and the second ball on the standing ball
valve assembly is lifted by the ball cage off the second ball
seat;
lowering the travelling ball valve onto the standing ball
valve assembly, such that the first pin extends through the
first ball seat to prevent the first ball from engaging the
first ball seat on the travelling ball valve and the
travelling valve acts upon the pivot linkage to pivot the ball
cage to the circulating position to prevent the second ball
from engaging the second ball seat on the standing ball valve
assembly, thereby permitting an unfettered circulation of
fluids through both the travelling ball valve and the standing
ball valve assembly.
2. A method of circulating through a reciprocating downhole
tubing pump which has a standing ball valve and a travelling
ball valve positioned downhole, comprising the steps of:
providing a standing ball valve assembly that has:
an upstanding first pin secured on top of the
standing ball valve assembly, the first pin being in axial

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alignment with a first ball seat which receives a first ball
on the travelling ball valve;
a second ball seat which receives a second ball,
the second ball being confined within a ball cage;
a rigid pivot linkage having a first end and a
second end, the first end being secured to the ball cage with
a fulcrum positioned between the first end and the second end,
such that when a downward force is exerted on the second end
of the pivot linkage, the pivot linkage pivots about the
fulcrum lifting the ball cage from an operative position to a
circulating position in which the raised ball cage lifts the
second ball on the standing ball valve assembly from the
second ball seat;
an upstanding second pin secured to the second end
of the pivot linkage and extending above the standing ball
valve assembly adjacent to the first pin;
lowering the travelling ball valve onto the standing ball
valve assembly, such that the first pin extends through the
first ball seat to prevent the first ball from engaging the
first ball seat on the travelling ball valve and the second
pin acts upon the pivot linkage to pivot the ball cage to the
circulating position to prevent the second ball from engaging
the second ball seat on the standing ball valve assembly,
thereby permitting an unfettered circulation of fluids through
both the travelling ball valve and the standing ball valve
assembly.
3. A reciprocating downhole tubing pump, comprising:
a barrel;
a travelling ball valve axially movable along the barrel,
the travelling valve having a first ball seat which receives a
first ball;
a standing ball valve assembly positioned within the
barrel, the standing ball valve assembly including a second
ball seat which receives a second ball, the second ball being

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confined within a ball cage;
an upstanding first pin secured on top of the standing
ball valve assembly, the first pin being in axial alignment
with a first ball seat which receives a first ball on the
travelling ball valve;
a rigid pivot linkage having a first end and a second
end, the first end being secured to the ball cage with a
fulcrum positioned between the first end and the second end,
such that when a downward force is exerted on the second end
of the pivot linkage, the pivot linkage pivots about the
fulcrum lifting the ball cage from an operative position to a
circulating position in which the raised ball cage lifts the
second ball on the standing ball valve assembly from the
second ball seat;
an upstanding second pin secured to the second end of the
pivot linkage and extending above the standing ball valve
assembly adjacent to the first pin, such that when the
travelling ball valve is lowered onto the standing ball valve
assembly the first pin extends through the valve seat to
prevent the first ball from engaging the first ball seat on
the travelling ball valve and the second pin acts upon the
pivot linkage to pivot the ball cage to the circulating
position to prevent the second ball from engaging the second
ball seat on the standing ball valve assembly, thereby
permitting an unfettered circulation of fluids through both
the travelling ball valve and the standing ball valve
assembly.

Description

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1
TITLE OF THE INVENTION:
A method of circulating through a reciprocating downhole
tubing pump and a reciprocating downhole tubing pump
FIELD OF THE INVENTION
The present invention relates to a :methcd of circulating
through a reciprocating downhole tubing pump and a
reciprocating downhole tubing pump which has been modified in
accordance with the teachings of the method.
BACKGROUND OF THE INVENTION
A reciprocating downhole tubing pump has a standing ball
valve and a travelling ball valve positioned downhole.
Blockages periodically occur in the tubing string. The
blockages are usually the result of an accumulation of sand
below the standing ball valve of such downhole tubing pumps.
Although the blockages can occur above or in the downhole
tubing pump. when this occurs, the entire tubing string and
downhole tubing pump are pulled from the well using a service
rig. The blockage is then removed from the tubing at
surface. Before you run back in with the production string
you must bail or circulate to remove sand accumulations down
hole in order to reposition the down hole tubing pump at the
desired depth.
SUi~I~RY OF THE INVENTION
What is required is a method of c~_rculating through the
standing ball valve assembly and travelling valve of a
downhole tubing pump, without having to pull the tubing
string and the downhole tubing pump from the well.
According to one aspect of the present invention there
is provided a method of circulating through a reciprocating
downhole tubing pump which has a standing ball valve and a
travelling ball valve positioned downhole. A first step

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involves providing first means for mechanically displacing
and disabling, without removing, a ball from a ball seat on
the travelling ball valve. A second step involve providing
second means for mechanically displacing and disabling,
without removing, a ball from a ball seat on the standing
valve assembly. A third step involves activating the first
means to prevent the ball from engaging the ball seat on the
travelling ball valve and the second means to prevent the
ball from engaging the ball seat on the standing ball valve
assembly and circulating fluids through both the travelling
ball valve and the standing ball valve assembly.
According to another aspect of the present invention
there is provided a reciprocating downhole tubing pump which
includes a barrel and a piston axially movable along the
barrel. A travelling ball valve is carried by the piston.
The travelling valve has a ball seat which receives a ball.
First means are provided for mechanically displacing and
disabling, without removing, the ball from the ball seat on
the travelling ball valve. A standing ball valve assembly is
positioned within the barrel. The standing ball valve
assembly includes a ball seat which receives a ball. Second
means are provided for mechanically displacing and disabling,
without removing, the ball from the ball seat: on the standing
valve assembly. Means are provided for activating the first
means to prevent the ball from engaging the ball seat on the
travelling ball valve and the second means to prevent the
ball from engaging the ball seat on the standing ball valve
assembly, such that a circulation of fluids c:an occur through
both the travelling ball valve and the stand~_ng ball valve
assembly.
The above described method sets forth the broad aspects
of the present invention. Once the inventive concept is

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understood, there may be different ways of putting it into
effect. As will be hereinafter described, in the preferred
embodiment an upstanding first pin is secured on top of the
standing ball valve assembly. This first pin is in axial
alignment with a ball seat, which receives a ball on the
travelling ball valve. A rigid pivot linkage is provided
having a first end and a second end. The first end is
secured to the ball cage with a fulcrum positioned between
the first end and the second end, such that when a downward
force is exerted on the second end of the pivot linkage, the
pivot linkage pivots about the fulcrum lifting a ball cage
from an operative position to a circulating position in which
the raised ball cage lifts the ball on the standing ball
valve assembly from the ball seat. An upstanding second pin
is secured to the second end of the pivot linkage extending
above the standing ball valve assembly adjacent to the first
pin. When the travelling ball valve is lower onto the
standing ball valve assembly, the first pin extends through
the valve seat to prevent the ball from engaging the ball
seat on the travelling ball valve and the second pin acts
upon the pivot linkage to pivot the ball cage to the
circulating position to prevent the ball from engaging the
ball seat on the standing ball valve assembly. This permits
an unfettered circulation of fluids through both the
travelling ball valve and the standing ball valve assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the invention will become
more apparent from the following description in which
reference is made to the appended drawings, the drawings are
for the purpose of illustration only and are not intended to
in any way limit the scope of the invention to the particular
embodiment or embodiments shown, whereino
FIGURE 1 is a side elevation view, in section, of a

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reciprocating downhole tubing pump constructed in accordance
with the teachings of the present method with the standing
ball valve assembly and the travelling valve in an operative
position.
FIGURE 2 is a side elevation view, in section, of the
reciprocating downhole tubing pump illustrated in FIGURE 1,
with the standing ball valve assembly and the travelling
valve in a circulating position.
FIGURE 3 is a detailed side elevation view, in section,
of an offset transfer ball cage and pivot linkage constructed
in accordance with the teachings of the present method.
DETAILED DESCRIPTION OF THE PREFERRED EN~ODIMENT
The preferred embodiment, a reciprocating downhole
tubing pump generally identified by reference numeral 10,
will now be described with reference to FIGURES 1 through 3.
Structure and Relationship of Partse
Referring to FIGURE ~, reciprocating downhole tubing
pump 10 has a barrel 12. A piston 13 transports a travelling
ball valve 14 having a first ball seat 1.6 and a first ball 18
is axially movable along barrel 12. A standing ball valve
assembly 20 having a second ball seat 22 and a second ball 24
is positioned within barrel 12. Second ball 24 is confined
within a ball cage 26. An upstanding first pin 28, in axial
alignment with first ball seat 16 and first ball 18 of
travelling ball valve 14, is secured on. top of standing ball
valve assembly 20. Standing ball valve assembly 20 is
further adapted with a rigid pivot linkage 30, an offset
transfer body 31 and a screen 32. Referring to FIGURE 3,
rigid pivot linkage 30 has a first end 33 and a second end
34. A fulcrum 36 is positioned between first end 33 and
second end 34. When a downward force 38 is exerted on second
end 34, linkage 30 pivots about fulcrum 36, lifting ball cage

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26 and second ball 24 from an operative position to a
circulating position. An upstanding second pin 40 is secured
to second end 34 of linkage 30 and extends above standing
ball valve assembly 20 adjacent to first pin 28. Referring
5 to FIGURE 2, when piston 13 transports 'travelling ball valve
14 onto standing ball valve assembly 20, first pin 28 extends
through first valve seat 16, preventing first ball 18 from
engaging first ball seat 16 in travelling ball valve 14.
Upon contact with travelling ball valve 14, second pin 40
acts upon pivot linkage 30, pivoting ball cage 26 to a
circulating position by preventing second ball 24 from
engaging second ball seat 22 of standing ball valve assembly
20, allowing an unfettered circulation ef fluids through both
travelling ball valve 14 and standing ball valve assembly 20.
Operation:
The use and operation of reciprocating downhole tubing
pump 10 in accordance with the teachings of the preferred
method, will now be described with reference to FIGURES I
through 3. Referring to FIGURE 2, where a blockage of sand
or other impediment occurs below standing ba.l1 valve assembly
20, piston 13 with travelling ball valve 14 is positioned
within barrel 12 above standing ball valve assembly 20 as
provided. Referring to FIGURE 3, as piston 13 with
travelling ball valve 14 is lowered and contact is made with
standing ball valve assembly 20, upstanding second pin 40
exerts downward force 38 onto second end 34 of rigid pivot
linkage 30, lifting ball cage 26 and unseating second ball 24
from second seat 22 and opening standing ball valve 20 for
circulation. Referring to FIGURE 2. similarly, upstanding
first pin 28 unseats first ball 18, opening travelling ball
valve 14 for circulation. As both valves are in a
circulating position, any blockages may then be cleared by
the flow of fluid. The blockage is then removed from the

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tubing at surface. Very little extra preparation is required
to get the well into production again. This concept saves
the need of removing the reciprocating downhole tubing pump,
circulating or running a sand bailer, and then reinstalling
the reciprocating downhole tubing pump.
Variations:
It should be noted that the dislodging and disabling of
the ball on the travelling valve and the ball on the standing
valve can be done in either order or simultaneously. In
field trials the ball on the standing valve was dislodged and
disabled first. The reason for this was that the ball on the
standing valve is not subjected to the same fluid pressure,
as the ball on the travelling valve is generally holding the
fluid weight in the tubing.
It is desirable to place a screen below the standing
ball valve assembly. The screen serves two valuable
functions. When fluid is flowing in an upward direction
through the standing ball valve assembly, it prevents debris
which cannot be pumped from entering and acts as a vortex to
break up fluid composition prior to entering pump. When
fluid is flowing in a downward direction, it acts as a spray
nozzle.
Advantages:
There are a number of advantages obtainable through the
use of the method and apparatus, as described above:
1. At the present time hours of rig time are spent during
pump installation to circulate fluids to clean out sand
fill or using bailers to bail sand accumulations to clean
up the cellar. With the present invention, one can
circulate the reciprocating downhole tubing pump into the
desired landing depth. One way this may be done is by
pinning the pump with shear screws. Once in position, an

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anchor can be set and a force can be exerted upon the
pump to shear the shear screws to open up the pump
stroke.
2. The ability to circulate enables you to pump fluid into
the formation, to assist in opening up the perforations
or the formation.
3. If the formation is tight, you could circulate the entire
hole over by sending fluid down tubing and up and out the
casing.
IO 4. If a blockage should occur .i_n the pump, above the pump or
below the pump, the blockage can be addressed by direct
circulation of fluids which flushes the tubing string of
blockages. While blockages mainly occur below the pump,
they sometimes occur elsewhere in the tubing string.
5. The described invention can be used in conjunction with
other tools, such as a scraper, a casing swabbing device
or drill out equipment to accomplished several tasks in
one operation.
In this patent document, the word "comprising" is
used in its non-limiting sense to mean that items following
the word are included, but items not specifically mentioned
are not excluded. A reference to an element by the
indefinite article "a°° does not exclude the possibility that
more than one of the element is present, unless the context
clearly requires that there be one and only one of the
elements.
It will be apparent to one skilled in the art that
modifications may be made to the illustrated embodiment
without departing from the spirit and scope of the invention
as hereinafter defined in the Claims.

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