SUCKER ROD COUPLER

RACCORD DE TIGE DE POMPAGE

English Abstract

A sucker rod coupler includes an elongate coupling body
less then three feet in length having an exterior surface and
opposed ends. Coupling members are positioned at each of the
opposed ends of the elongate coupling body. Each of the
coupling members have an exterior surface. The elongate
coupling body has a cross-sectional thickness that is less than
the cross-sectional thickness of the coupling members. A guide
body is positioned on the exterior surface of the elongate
coupling body. The guide body has a plurality of guide vanes
with flow channels positioned between the guide vanes. The
guide vanes extend radially from the guide body past the
exterior surface of each of the coupling members.

Claims

6
THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A sucker rod coupler, comprising:
an elongate coupling body less then three feet in length
having an exterior surface and opposed ends;
coupling members at each of the opposed ends of the
elongate coupling body, each of the coupling members having an
exterior surface;
the elongate coupling body having a cross-sectional
thickness that is less than the cross-sectional thickness of
the coupling members;
a guide body positioned on the exterior surface of the
elongate coupling body, the guide body having a plurality of
guide vanes with flow channels positioned between the guide
vanes, the guide vanes extending radially from the guide body
past the exterior surface of each of the coupling members.

Description

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TITLE OF THE INVENTION:
Sucker Rod Coupler
NAMES) OF INVENTOR(S):
Thomas Hubert Vermeeren
FIELD OF THE INVENTION
The present invention relates to a Sucker Rod Coupler
BACKGROUND OF THE INVENTION
Sucker rods come in standard lengths. For example, a
large proportion of the sucker rods used in wells in North
America comes in standard 25 foot lengths. When a length in
excess of 25 feet is required, two 25 foot lengths of sucker
rod are connected using a sucker rod coupler. A sucker rod
coupler is a short length of steel tube, typically 4 inches in
length. The tube is of consistent cross-sectional dimension
and has internal threads at either end for the sucker rod to
thread into.
When a length of sucker rod is in a well, it tends to
deflect as it rotates due to compression or deviations in the
borehole. Wear occurs should the sucker rod rub against the
well tubing. To prevent such contact from occurring rod guides
are provided. Rod guides are members that attach to the sucker
rod to centralize the sucker rod as it rotates within the well
tubing. The rod guides generally consist of a plurality of
vanes with flow channels inbetween, in order to provide a path
for the flow of fluids past the rod guide.
Where wear due to rubbing in the vicinity of the sucker
rod coupler is of concern, two sucker rod couplers are utilized
with a rod guide positioned between them. While this
configuration addresses the rubbing problem it has a number of
inherent drawbacks. When two sucker rod couplers are used with
a rod guide positioned inbetween, it requires several
additional joints and creates constriction with diminished

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fluid flow. The trend in the industry has, therefore, been to
place rod guides onto the sucker rods, so that there is no need
for rod guides in the vicinity of the sucker rod couplers.
SUMMARY OF THE INVENTION
What is required is an alternative sucker rod coupler
construction.
According to the present invention there is provided a
sucker rod coupler which includes an elongate coupling body
less then three feet in length having an exterior surface and
opposed ends. Coupling members are positioned at each of the
opposed ends of the elongate coupling body. Each of the
coupling members has an exterior surface. The elongate
coupling body has a cross-sectional thickness that is less than
the cross-sectional thickness of the coupling members. A guide
body is positioned on the exterior surface of the elongate
coupling body. The guide body has a plurality of guide vanes
with flow channels positioned between the guide vanes. The
guide vanes extend radially from the guide body past the
exterior surface of each of the coupling members.
The sucker rod coupler, as described above, is
specifically designed to perform the function of centralizing
the joint between two sucker rods while providing improved
fluid flow. Field installation of rod guides or replacement
of worn rod guides is simplified, when installation or repair
can be effected merely by substituting sucker rod couplers.
This is in marked contrast to rod guides positioned on the
sucker rods, which in most cases requires removal to the sucker
rods to remote repair facilities.
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, wherein:

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FIGURE 1, labelled as PRIOR ART is a perspective view of
two sucker rod couplers coupling two sucker rods, with a rod
guide disposed between the two sucker rod couplers.
FIGURE 2, labelled as PRIOR ART is a side elevation view,
in section, of the flow channels provided by the configuration
illustrated in FIGURE 1, when positioned within well tubing.
FIGURE 3 is a perspective view of a sucker rod coupler
constructed in accordance with the teachings of the present
invention.
FIGURE 4 is a side elevation view, in section, perspective
view of the flow channels provided by sucker rod coupler
illustrated in FIGURE 3, when positioned within well tubing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment, a sucker rod coupler, generally
identified by reference numeral 10, will now be described with
reference to FIGURES 1 through 4.
Referring to FIGURE 1, a PRIOR ART configuration for
coupling two lengths of sucker rod is illustrated, which
configuration is generally identified by reference numeral 12.
Coupling configuration 12 includes a first sucker rod coupler
14 and a second sucker rod coupler 16 with a rod guide 18
positioned inbetween. Each of first sucker rod coupler 14 and
second sucker rod coupler 16 has a threaded female socket 20
which mates with a threaded male member 22 from a sucker rod
24. Rod guide 18 has a plurality of guide vanes 26 that extend
radially from rod guide 18 past first coupling member 14 and
second coupling member 16. Referring to FIGURE 2, which is
labelled PRIOR ART, when positioned in well tubing 27,
configuration 12 provides flow channels 28 between guide vanes
24.
Referring to FIGURE 3, sucker rod coupler 10 includes an
elongate coupling body 30 less then three feet in length having
an exterior surface 32 and opposed ends 34. Female coupling
members 36 are positioned at each of opposed ends 34 of

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elongate coupling body 30. Each of coupling members 36 has an
exterior surface 38. Elongate coupling body 30 has a cross-
sectional thickness that is less than a cross-sectional
thickness of the coupling members 36. A guide body 44 is
positioned coaxially on exterior surface 32 of elongate
coupling body 30 at a position between coupling members 36.
Guide body 44 has a cross-sectional thickness that is less than
a cross-sectional thickness of the coupling members 36. Guide
body 44 has a plurality of guide vanes 46. Referring to FIGURE
4, flow channels 48 are positioned between guide vanes 46.
Referring to FIGURE 3, Guide vanes 46 extend radially from
guide body 44 past exterior surface 38 of each of coupling
members 36. Each coupling member 36 mates with one of threaded
male members 22 from sucker rods 24.
The use and operation of sucker rod coupler 10 will now
be described with reference to FIGURES 1 through 4. Sucker rod
coupler 10 couples two sucker rods 24, as illustrated in FIGURE
3. Sucker rod coupler 10 is, however, specifically designed
to provide improved flow when compared with PRIOR ART coupling
configuration 12, illustrated in FIGURES 1 and 2. The flow
area provided by coupling configuration 12 represents
approximately 20% of the total area of well tubing 27.
Referring to FIGURE 4, flow channels 48 of sucker rod coupler
10 provide a flow area which is approximately 36% of the total
area of well tubing 27. This increase of 16% almost doubles
the flow area available. In addition, two joints required by
coupling configuration 12 are eliminated. Field installation
of sucker rod couplers 10, or replacement of guide vanes 46 can
be effected merely by substituting a new sucker rod coupler 10
for the existing sucker rod coupler.
With PRIOR ART coupling configuration 12, illustrated in
FIGURE 2, a restriction in the flow area is created as a result
of the diameter of rod guide 18, which is always equal to or
greater than the diameter of coupling bodies 14 and 16. In
contrast, with sucker rod coupler 10, the diameter of coupling

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body 30 is always less than the diameters of coupling members
36. The greatest flow restriction is, therefore, at coupling
members 36. The diameter of guide body 44 is always smaller
than the diameter of coupling members 36.
5
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.

Representative Drawing