Note: Descriptions are shown in the official language in which they were submitted.
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TITLE OF THE INVENTION:
A Method of Controlling A Pipeline Plow And A Pipeline
Plow
NAME ( S ) OF INVENTOR ( S )
Dean Richard McCrindle
FIELD OF THE INVENTION
The present invention relates to a method of controlling
a pipeline plow and a pipeline plow manufactured in accordance
with the teachings of the method.
BACKGROUND OF THE INVENTION
Pipeline plows are used, as an alternative to trench
excavations, to bury pipelines underground. A pipeline plow
has a ground working blade with a leading edge and a trailing
edge. A pipeline feed chute generally extends downwardly at
an angle from the leading edge to the trailing edge. A
pipeline enters the pipeline feed chute above ground level from
the leading edge and exits the pipeline feed chute underground
from the trailing edge. Rollers are often positioned in the
pipeline feed chute to reduce friction acting upon the pipeline
as it slides along the pipeline feed chute.
In order to use a pipeline plow, the ground along a
pipeline right of way is first loosened by a ground ripper
attached to a crawler tractor. The pipeline plow is then
secured in an off-set orientation behind the crawler tractor
and the pipeline being fed over one of the tracks of the
crawler tractor into the pipeline feed chute at the leading
edge of the pipeline plow. This method of controlling the
pipeline plow has an inherent problem. The off-set feed of the
pipeline over the tracks of the crawler tractor into the
pipeline plow causes a constant pull which tends to turn the
crawler tractor and makes it difficult to control both the
crawler tractor and the pipeline plow.
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SUMMARY OF THE INVENTION
What is required is an alternative method of controlling
a pipeline plow.
According to one aspect of the present invention there is
provided a pipeline plow that was developed in accordance with
the teachings of the method. The pipeline plow includes a
narrow elongate body having a leading edge, a trailing edge and
opposed sides. A pipeline feed chute extends along the body
between the leading edge and the trailing edge. A tow line
attachment is positioned at the leading edge of body. A
steering arm attachment is secured to the body.
According to another aspect of the present invention there
is provided a method of controlling a pipeline plow. A
modified form of pipeline plow is used, substantially as
described above. A vehicle equipped with a movable arm is
positioned either behind the trailing edge or to one of the
opposed sides of the pipeline plow. The movable arm is secured
to the steering arm attachment. A tow line is extended from
the tow line attachment to one or two tow vehicles positioned
a spaced distance from the pipeline plow. The pipeline plow
is towed at the end of the tow line, while the path the
pipeline plow follows is concurrently controlled with the
movable arm.
With the method described in the prior art, the crawler
tractor pulling the pipeline plow was never able to exert a
full pulling force, as correction had to be continually made
to control the alignment of the pipeline plow. In contrast,
with the present method towing function and the steering
function are separated. The tow vehicle performing the towing
function is, therefore, able to exert a much greater pulling
force without being constrained by steering problems. It is
also possible to use two tow vehicles to double the available
pulling force. With the method as described in the prior art,
the crawler tractor pulling the pipeline plow drove ahead of
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the plow. In doing so, the crawler tractor inevitably
compacted the loosened ground. In some types of terrain, such
as muskeg, the pipeline plow could not be used, as the crawler
tractor would sink into the ground. In contrast, with the
present method one or, preferably, two tow vehicles can be used
each laterally spaced from the area of loosened ground.
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:
FIGURE 1 labelled as PRIOR ART is a side elevation view
of a crawler tractor pulling a pipeline plow.
FIGURE 2 labelled as PRIOR ART is a top plan view of the
crawler tractor pulling a pipeline plow illustrated in FIGURE
1.
FIGURE 3 is a side elevation view of a crawler tractor
pulling a pipeline plow in accordance with the teachings of the
present invention.
FIGURE 4 is a top plan view of the crawler tractor pulling
the pipeline plow illustrated in FIGURE 1.
FIGURE 5 is a perspective view of a pipeline plow
constructed in accordance with the teachings of the present
invention.
FIGURE 6 is a top plan view of the pipeline plow
illustrated in FIGURE 5.
FIGURE 7 is a front elevation view of the pipeline plow
illustrated in FIGURE 5.
FIGURE 8 is a side elevation view, partially in section,
of the pipeline plow illustrated in FIGURE 5.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment, a pipeline plow generally
identified by reference numeral 10, will now be described with
reference to FIGURES 1 through 8.
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Referring to FIGURES 1 and 2, labelled as PRIOR ART, the
drawbacks of current methods of controlling pipeline plows is
illustrated. A vehicle, illustrated in FIGURES 1 as a crawler
tractor 12, is provided. Referring to FIGURE 1, crawler
tractor 12 travels over the surface 14 of the ground 16 pulling
a PRIOR ART pipeline plow 100 in a direction indicated by arrow
22. Referring to FIGURE 2, a portion 18 of ground 16 has been
loosened in preparation for laying of a pipeline 20 beneath
surface 14.
Referring to FIGURE l, PRIOR ART pipeline plow 100 has a
ground working blade 101 . Ground working blade 101 has a f first
end 102, a second end 104, a lower surface 106, an upper edge
108, a leading edge 109, and a trailing edge 110 extending
downward from upper edge 108 to second end 104. A projecting
plowshare 112 extends from leading edge 109 at first end 102
adjacent lower surface 106. Referring to FIGURE 2, leading
edge 109 adjacent upper edge 108 is secured in an off-set
position at a rear 24 of crawler tractor 12 to enable crawler
tractor 12 to pull PRIOR ART pipeline plow 100. Referring to
FIGURE l, ground working blade 101 has a pipeline feed chute
114 extending downward from an entrance 116 above ground level
14 at leading edge 109 to an exit 118 underground adjacent
lower surface 106 at second end 104. Pipeline 20 is fed
through entrance 116 into pipeline feed chute 114. As ground
working blade 101 is pulled in direction 22, plowshare 112
displaces loosened soil 18 and ground working blade 101 moves
through loosened soil 18 in direction 22, with lower surface
106 beneath and substantially parallel to surface 14 of ground
16. Pipeline 20 moves along pipeline feed chute 116 and is
laid beneath surface 14, the loosened soil backfilling over the
section of laid pipeline 26. Rollers (not shown) are
positioned in pipeline feed chute 114 to reduce friction acting
upon pipeline 20 as it slides along pipeline feed chute 114.
Referring to FIGURE 2, when PRIOR ART pipeline plow 100
is secured in an off-set orientation behind crawler tractor 12,
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pipeline 20 is fed over one of the tracks 30 of crawler tractor
12 into pipeline feed chute 114. This method of controlling
pipeline plow 100 has an inherent problem. The off-set feed
of pipeline 20 over one of tracks 30 of crawler tractor 12 into
5 pipeline plow 100 causes a constant pull which tends to turn
crawler tractor 20 and makes it difficult to control both
crawler tractor 20 and pipeline plow 100. As a consequence,
crawler tractor 12 pulling pipeline plow 100 is never able to
exert a full pulling force, as corrections have to be
continually made to control the alignment of pipeline plow 100.
Further, one of tracks 30 of crawler tractor 12 unavoidably
travels over loosened soil 18, thereby recompressing it.
Referring to FIGURES 5 through 8, pipeline plow 10 was
developed for use in accordance with the preferred method,
which will hereinafter be further described with reference to
FIGURES 3 and 4. Referring to FIGURE 5, pipeline plow 10
includes a narrow elongate body 32 having a leading edge 34,
a trailing edge 36, opposed sides 38, an upper edge 40 and a
lower surface 42. A tow line attachment 46 is at leading edge
34 of body 32. A steering arm attachment 60 is secured at
upper edge 40 toward leading edge 34 of body 32. A plowshare
62 is detachably secured at leading edge 34 adjacent lower
surface 42 of body 32.
Referring to FIGURE 8, a pipeline feed chute 44 extends
along body 32 between an entrance 48 at leading edge 34 at a
position toward upper edge 40 and an exit 50 at trailing edge
36 adjacent lower surface 42. First guide rollers 52 are
positioned as entrance 48 so as to guide pipeline 20 into
pipeline feed chute 44, as shown in FIGURE 3, without
contacting a peripheral edge 54 of entrance 48. A plurality
of second guide rollers 56 is positioned within pipeline feed
chute 44, so as to guide pipeline 20 through pipeline feed
chute 44 without rubbing an inside surface 58 of pipeline feed
chute 44.
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The preferred method of controlling pipeline plow 10 will
now be described with reference to FIGURES 3 and 4. Referring
to FIGURE 3, pipeline plow 10 is provided as described above.
A positioning vehicle 70 is equipped with a movable arm 72.
Positioning vehicle 70 is positioned at one of trailing edge
36 and opposed sides 38 of pipeline plow 10. For purposes of
illustration only, positioning vehicle 70 is shown positioned
at trailing edge 36 of pipeline plow 10 in FIGURES 3 and 4.
Referring to FIGURE 3, movable arm 72 is attached to steering
arm attachment 60 of pipeline plow 10. A towline 66 is
extended between rear 24 of tow vehicle, shown as crawler
tractor 12, distanced from leading edge 34 and towline
attachment 46 of body 32 of pipeline plow 10. It will be
recognized that a plurality of towlines 66 may be extended from
more than one crawler tractors 12 positioned a spaced distance
from pipeline plow 10. Pipeline plow 10 is towed at an end 74
of tow line 66, while movable arm 72 is used to concurrently
control the path of pipeline plow 10 through loosened soil 18.
Referring to FIGURE 4, when positioning vehicle 70 is
positioned at trailing edge 36 of pipeline plow 10, movable
arm, the position of which is shown by dotted lines in FIGURE
4, overlies body 32 of pipeline plow 10, enabling both a good
view of the path of pipeline plow 10 and a high degree of
control of the direction of movement of pipeline plow 10.
It will be apparent to one skilled in the art that
advantages are provided by the above described method.
Referring to FIGURE 4, towing attachment 78 of crawler tractor
12 is shown in an offset position. There is no longer a need
for towing attachment 78 on crawler tractor 12, to be in an
offset position. Towing attachment 78 can be centrally
positioned, so that crawler tractor 12 is not pulled to one
side when a pulling force is exerted. Crawler tractor 12 can
exert a full pulling force, without being constrained by the
need to concurrently control the direction and orientation of
pipeline plow 10. This separation of pulling and steering
functions between crawler tractor 12 and positioning vehicle
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70 allows separate and superior control of both the applied
power and the direction of movement of pipeline plow. When
there is a need for greater pulling power, more than one
crawler tractor 12 can be used to pull pipeline plow 10.
Crawler tractor 12 does not need to travel over loosened soil,
but can travel parallel to the path of loosened soil 18. As
a consequence, crawler tractor 12 is able to apply a
substantially full pulling force to move pipeline plow 10, and
to do so without risk of recompressing loosened soil 18.
l0
It also 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.