System for conveying a fluid through an under-the-ground location and method of making the same

A system for conveying a fluid through an under-the-ground location and method of making the same are provided, the system comprising a primary flexible conduit for conveying the fluid therethrough and having an outer peripheral surface and an inner peripheral surface, and an outer secondary conduit having at least a portion of the primary conduit removably disposed therein and having an inner peripheral surface and an outer peripheral surface that engages the ground in the under-the-ground location thereof, the secondary conduit having the inner peripheral surface thereof comprising a helically disposed and inwardly directed projection thereof that engages the outer peripheral surface of the primary conduit in a spiral manner and cooperates therewith to define a helically disposed passage that extends therebetween throughout substantially the entire engagement area thereof.

BACKGROUND OF THE INVENTION 
1. Field of the invention 
This invention relates to a new system for conveying a fluid through an 
under-the-ground location and method of making such a system. 
2. Prior Art Statement 
It is known to provide a system for conveying a fluid through an 
under-the-ground location, the system comprising a primary flexible 
conduit means for conveying the fluid therethrough and having an inner 
peripheral surface means and an outer peripheral surface means, and an 
outer secondary conduit means having at least a portion of the primary 
conduit means removably disposed therein and having an inner peripheral 
surface means and an outer peripheral surface means that engages the 
ground in the under-the-ground location thereof. For example, see the Webb 
et al, U.S. Pat. No. 4,971,477. 
It is also known to provide a primary conduit means that has a helically 
disposed passage formed therein throughout the length thereof (see the 
Winter et al, U.S. Pat. No. 5,089,074) with coupling means for coupling 
each end of the primary conduit means to other fluid conveying structure 
(see the Sanders et al, U.S. Pat. No. 5,129,686) and to either bury that 
primary conduit means directly into the ground or dispose the same within 
a secondary conduit means that is buried in the ground (see the Foster, 
U.S. Pat. No. 5,102,012) . 
It is also known to provide a flexible hose having its inner peripheral 
surface means defined by a projection means that is helically disposed 
throughout the length thereof and having a fluid conveying conduit means 
disposed therein. For example, see the Grantham, U.S. Pat. No. 4,951,720. 
It is also known to provide a plurality of uniformly spaced apart radially 
disposed ribs on the inner peripheral surface means of a secondary conduit 
means so that at least some of the ribs will engage the outer peripheral 
surface means of the primary conduit means in the under-the-ground 
location thereof. The inner edges of the ribs on the secondary conduit 
means define an internal diameter that is substantially larger than the 
external diameter defined by the external peripheral surface means of the 
primary conduit means when the primary conduit means is disposed in the 
secondary conduit means before the combination thereof is disposed in the 
ground. For example, see the March, 1992 Form A 115 pamphlet of Advanced 
Polymer Technology, Inc. of Elkhart, Ind. 
SUMMARY OF THE INVENTION 
It is one of the features of this invention to provide a new system for 
conveying a fluid in an under-the-ground location by utilizing a unique 
combination of a primary conduit means and a surrounding secondary conduit 
means to create a helically disposed passage that extends therebetween. 
In particular, it is believed according to the teachings of this invention 
that the inner peripheral surface means of the secondary conduit means can 
comprise a helically disposed and inwardly directed projection thereof 
that engages the outer peripheral surface means of the primary conduit 
means in a spiral manner and cooperates therewith to define a helically 
disposed passage that extends therebetween throughout substantially the 
entire engagement area thereof. 
It is also believed that such engagement of the projection of the secondary 
conduit means with the outer peripheral surface means of the primary 
conduit means not only provides reinforcement means for the primary 
conduit means so that the same can effectively convey a fluid therethrough 
in an under-the-ground location thereof or the like, but also the 
resulting helically disposed passage can be utilized for leak detection 
purposes, such as for detecting for leakage of the fluid from the primary 
conduit means through the outer peripheral surface means thereof. 
For example, one embodiment of this invention comprises a system for 
conveying a fluid through an under-the-ground location, the system 
comprising a primary flexible conduit means for conveying the fluid 
therethrough and having an inner peripheral surface means and an outer 
peripheral surface means, and an outer secondary conduit means having at 
least a portion of the primary conduit means removably disposed therein 
and having an inner peripheral surface means and an outer peripheral 
surface means that engages the ground in the under-the-ground location 
thereof, the secondary conduit means having the inner peripheral surface 
means thereof comprising a helically disposed and inwardly directed 
projection thereof that engages the outer peripheral surface means of the 
primary conduit means in a spiral manner and cooperates therewith to 
define a helically disposed passage that extends therebetween throughout 
substantially the entire engagement area thereof. 
Accordingly, it is an object of this invention to provide a new system for 
conveying a fluid through an under-the-ground location, the system of this 
invention having one or more of the novel features of this invention as 
set forth above or hereinafter shown or described. 
Another object of this invention is to provide a new method of making such 
a system, the method of this invention having one or more of the novel 
features of this invention as set forth above or hereinafter shown or 
described. 
Other objects, uses and advantages of this invention are apparent from a 
reading of this description which proceeds with reference to the 
accompanying drawings forming a part thereof and wherein:

DESCRIPTION OF THE PREFERRED EMBODIMENT 
While the various features of this invention are hereinafter illustrated 
and described as being particularly adapted to provide a system for 
conveying a volatile liquid, such as gasoline, through an under-the-ground 
location, it is to be understood that the various features of this 
invention can be utilized singly or in various combinations thereof to 
provide a system for conveying other types of fluids through an 
under-the-ground location or the like as desired. 
Therefore, this invention is not to be limited to only the embodiments 
illustrated in the drawings, because the drawings are merely utilized to 
illustrate one of the wide variety of uses of this invention. 
Referring now to FIGS. 7-11, the new system of this invention is generally 
indicated by the reference numeral 20 and comprises one or more conduit 
arrangements of this invention that are each generally indicated by the 
reference numeral 21 and disposed in the ground 22 in an under-the-ground 
location thereof for conveying a fluid therethrough which in the 
embodiments illustrated in the drawings comprises gasoline being conveyed 
from an under-the-ground storage tank 23 to an above-the-ground dispensing 
pump means 24 all in the general manner that is fully set forth in the 
aforementioned to Webb et al, U.S. Pat. No. 4,971,477 and the Foster, U.S. 
Pat. No. 5,102,012 whereby these two U.S. patents are being incorporated 
into this disclosure by this reference thereto. 
Each conduit arrangement 21 illustrated in FIGS. 7-11 comprises the conduit 
arrangement 21 illustrated in FIGS. 1-3 which comprises a primary conduit 
means 25 and an outer surrounding secondary conduit means 26, each conduit 
means 25 or 26 being formed mainly of polymeric material and being 
relatively flexible. 
In particular, the primary conduit means 25 has an inner peripheral surface 
means 27 and an outer peripheral surface means 28 and comprises a 
structure that is fully disclosed and claimed in the aforementioned to 
Winter et al, U.S. Pat. No. 5,089,074 whereby this U.S. patent is also 
being incorporated into this disclosure by this reference thereto. 
Therefore, it can be seen that the primary conduit means 25 comprises an 
inner corrugated hose 29 defined by a plurality of outwardly directed 
annular projections 30 having recesses 31 therebetween which define the 
internal peripheral surface 27 of the primary conduit means 25 as a 
plurality of inwardly directed annular projections 32 having recesses 33 
therebetween. A tubular member 35 is disposed against the projections 30 
of the inner hose 29 and cooperates therewith to define void spaces 34 
therebetween for the reasons fully set forth in the aforementioned to 
Winter et al, U.S. Pat. No. 5,089,074. A reinforcing braid 36 is disposed 
on the tube 35 and an outer layer 37 of polymeric material has been 
extruded on top of the braid 36 and exuded therethrough to bond to the 
tube 35 and complete the flexible primary conduit means 25 that is 
presently being utilized as the primary conduit means in a system similar 
to the system set forth in the aforementioned to Webb et al, U.S. Pat. No. 
4,971,477, the outer layer 37 defining a relatively smooth outer 
peripheral surface means 28 of the primary conduit means 25. 
While the primary conduit means 25 has the inner hose 29 thereof defining 
annular projections 30 and 32 as previously described, it is to be 
understood that the projections could be helically disposed in the manner 
illustrated in FIGS. 4-6 wherein another conduit arrangement of this 
invention is generally indicated by the reference numeral 21A and parts 
thereof similar to the parts of the conduit arrangment 21 previously 
described are indicated by like reference numerals followed by the 
reference letter "A". 
It can be seen in FIGS. 4-6 that the conduit arrangement 21A is 
substantially identical to the conduit arrangement 21 previously described 
as well as hereinafter described, except that the inner hose 29A of the 
primary conduit means 25A has the outer and inner projections 30A and 32A 
thereof helically disposed so that the void space 34A being created in the 
primary hose 25A is actually a helically disposed passage that extends 
throughout the entire length of the primary conduit means 25A, such a 
helical arrangment being fully disclosed and claimed in the aforementioned 
to Winter et al, U.S. Pat. No. 5,089,074. 
The outer or secondary conduit means 26 of the combination 21, as well as 
the secondary conduit means 26A of the combination 21A, has an internal 
peripheral surface means 38 and an outer peripheral surface means 39, the 
inner peripheral surface means 38 comprising a plurality of inwardly 
directed projections 40 with recesses 41 therebetween while the outer 
peripheral surface means 39 comprises a plurality of outwardly directed 
projections 42 with recesses 43 therebetween. The outwardly directed 
projections 42 and inwardly directed projections 40 of the secondary 
conduit means 26 are helically disposed throughout the length of the 
primary conduit means 26 and a helically disposed reinforcement member 44 
is disposed in the helically disposed recess 41 as illustrated, the 
reinforcing means 44 comprising a metallic wire 45 covered with a 
polymeric material 46 which bonds to the polymeric material of the 
secondary conduit means 26 whereby it can be seen that the secondary 
conduit means 26 or 26A illustrated in the drawings is substantially 
identical to and is formed in substantially the same manner as the fully 
disclosed outer conduit means of the hose assemblies illustrated and 
described in the aforementioned to Grantham, U.S. Pat. No. 4,951,720 
whereby this U.S. patent is also being incorporated into this disclosure 
by this reference thereto. 
However, the internal diameter of the secondary conduit means 26 is so 
selected relative to the external diameter of the primary conduit means 25 
that the inward projection means 40 of the secondary conduit means 26 
engages in a spiral manner against the outer peripheral surface 28 of the 
primary conduit means 25, which is substantially smooth and generally 
straight-line continuous throughout the length thereof, to define or 
create a helically disposed substantially sealed passage 47 throughout 
substantially the entire engagement area of the secondary conduit means 26 
with the primary conduit means 25, such engagement occurring either when 
the primary conduit means 25 and secondary conduit means 26 are assembled 
together in an above-the-ground arrangement thereof or only when the 
combination 21 thereof is disposed in the under-the-ground location 
thereof and the ground 22 is compacting the secondary conduit means 26 
radially inwardly toward the primary conduit means 25 and/or the pressure 
of the fluid being conveyed through the primary conduit means 25 has 
radially outwardly expanded the primary conduit means 25 into contact with 
the projection means 40 of the secondary conduit means 26 in a manner 
hereinafter set forth. 
In any event, it can be seen that the helically disposed passage 47 between 
the conduit means 25 and 26 is unique in the art and can be uniquely 
utilized in the under-the-ground locations of the conduit arrangements 21 
in a manner hereinafter set forth. 
As illustrated in FIGS. 7 and 9, the secondary conduit means 26 of each 
combination 21 has like opposite ends 48 and the respective primary 
conduit means 25 for the arrangement 21 has like opposite ends 49 which 
respectively extend outboard of the ends 48 of the secondary conduit means 
26 as illustrated in the drawings and each comprises a coupling means 50 
best illustrated in FIG. 8 and being secured to an adjacent end 51 of the 
flexible hose structure of the primary conduit means 25 all in a manner 
fully disclosed and claimed in the aforementioned to Saunders et al, U.S. 
Pat. No. 5,129,686 whereby this U.S. patent is also being incorporated 
into this disclosure by this reference thereto. 
In this manner, the opposite ends 48 of the secondary conduit means 26 of 
each conduit arrangement 21 can be secured in substantially a sealed 
manner as disclosed in the aforementioned to Webb et al, U.S. Pat. No. 
4,971,477 in opening means 52 provided in appropriately spaced access 
chamber means 53 that are disposed in the ground 22 so that the opposite 
ends 49 of the primary conduit means 25 of the respective conduit 
arrangement 21 can be respectively disposed in chambers 54 defined by the 
access chamber means 53 to couple with suitable coupling structure, such 
as structure 55 or 56 illustrated in FIG. 7 wherein the structure 55 
couples to the dispensing pump means 24 while the coupling structure 56 
couples with an adjacent end 49 of another conduit arrangement 21 all for 
the purposes and reasons fully set forth in the aforementioned to Webb et 
al, U.S. Pat. No. 4,971,477 and the aforementioned to Foster, U.S. Pat. 
No. 5,102,012. 
It is believed that the unique conduit arrangement 21 of this invention 
readily permits the primary conduit means 25 to be removed from and be 
replaced in its respective secondary conduit means 26 after the respective 
combination 21 has been disposed in its under-the-ground location in the 
system 20 as the primary conduit means 25 is sufficiently flexible so that 
the same can be removed out through a respective access chamber means 53 
in the manner schematically illustrated in FIG. 9 and as fully described 
in the aforementioned to Webb et al, U.S. Pat. No. 4,971,477. 
It may be found that to facilitate such removal and such insertion, a 
suitable fluid, such as air under pressure, can be directed into the 
helically disposed passage 47 of the respective conduit arrangement 21 as 
represented by the pumping source 57 in FIG. 10 to tend to outwardly 
expand the secondary conduit means 26 away from its engagement with the 
primary conduit means 25 as schematically illustrated in FIG. 10. 
Also, as previously stated, the primary conduit means 25 could have such a 
dimension that the same is normally out of complete spiral contact with 
the projection means 40 of the secondary conduit means 26 in the manner 
illustrated in FIG. 10 until the fluid being directed therein from the 
under-the-ground storage tank means 23 is pumped therethrough under 
pressure in the manner illustrated in FIG. 11 so that when the source 23 
is removed from the primary conduit means 25 in the manner illustrated in 
FIG. 10, the primary conduit means 25 will shrink away from the secondary 
conduit means 26 and/or in combination with the pump means 57 to produce 
an arrangement wherein the primary conduit means 25 can be readily removed 
from the secondary conduit means 26 and a new primary conduit means 25 
reinserted therein as previously set forth. 
Also, while the coupling means 49 illustrated in FIG. 8 appears to be 
relatively large, it is to be understood that the same could have the 
various parts thereof so dimensioned that the same readily permits the 
entire primary conduit means 25 with its coupling means 49 to be removed 
therewith from its secondary conduit means 26 or inserted therewith as the 
case may be. Of course, it is to be understood that the couplings 49 could 
be cut off before a primary conduit means 25 is removed, as desired. 
In any event, it can be seen that in the combination 21 of this invention, 
the secondary conduit means 26 not only protects against any fluid leakage 
from the primary conduit means 25 from reaching the ground 22, but also 
through the engagement of the inner projection means 40 thereof, the 
secondary conduit means 26 provides reinforcement to the primary conduit 
means 25 in maintaining its fluid conveying function. 
In addition, it is believed that the helically disposed passage 47 of the 
conduit arrangement 21 can be utilized for leak detection purposes so as 
to determine whether any leakage of the fluid from within the primary 
conduit means 25 has permeated through any part of the external peripheral 
surface means 28 thereof and thereby reached the space 47 between the 
conduit means 25 and 26. For example, it is believed that a suitable leak 
detecting means 58, FIG. 11, can be so interconnected to the passage means 
47 of each conduit arrangement 21 that the leak detecting means 58 can 
detect for any leakage of fluid from the primary conduit means 25 to the 
space 47 between the conduit means 25 and 26, the leak detecting means 58 
comprising a pressure transducer, a gas sampling device, etc. Alternately 
or in lieu thereof the passage 47 could be utilized to carry a fiber optic 
means throughout the length of the passage 47 and be interconnected to the 
detector 58 for detecting for fluid leakage or the passage means 47 can be 
utilized for having a conductor (with or without a fluid dissolvable 
sheath thereon) disposed therein which would indicate to the device 58 
that leakage has occurred in a manner similar to the electrical leak 
detection means of the aforementioned to Foster, U.S. Pat. No. 5,102,012. 
In fact, the reinforcement 44 of the secondary conduit means 26 could 
comprise a conductor for such leak detection purpose in addition to its 
reinforcement purpose. 
In any event, it can be seen that the secondary conduit means 26 of each 
conduit arrangement 21 of this invention not only has the benefit of a 
secondary conduit means as set forth in the aforementioned to Webb et al, 
U.S. Pat. No. 4,971,477 and the Foster, U.S. Pat. No. 5,102,012 for its 
secondary containment purpose, but also the secondary conduit means 26 of 
this invention provides a reinforcement function for the primary conduit 
means 25 and/or a leak detection function through the unique helically 
disposed passage means 47 thereof. 
Likewise, if the primary conduit means 25 has the helically disposed 
passage 34A therein as provided by the conduit arrangement 21A previously 
described, such helically disposed passage 34A could also be utilized for 
leak detection purposes in a manner similar to the passage 47 to detect 
for leakage in the primary conduit means 25A before such leakage reaches 
the passage 47 between the conduit means 25A and 26A. 
While various parts have been previously illustrated and described for the 
system 20 of this invention, it is to be understood that other parts can 
be utilized. For example, the coupling for the outer ends 48 of the 
secondary conduit means 26 could each comprise a clamshell type of 
coupling whereby separate (or joined on one edge) parts are folded over 
the hose 26 and affixed together at their edges. Alternately, this 
coupling could also be spud glued to the primary conduit means 25 with a 
receptacle receiving the outer secondary conduit means 26 therein. 
In any event, it can be seen that it is a relatively simple method of this 
invention to make the system 20 of this invention to function in the 
manner previously set forth. 
Thus, this invention not only provides a new system for conveying a fluid 
through an under-the-ground location, but also this invention provides a 
new method of making such a system or the like. 
While the forms and methods of this invention now preferred have been 
illustrated and described as required by the Patent Statute, it is to be 
understood that other forms and method steps can be utilized and still 
fall within the scope of the appended claims wherein each claim sets forth 
what is believed to be known in each claim prior to this invention in the 
portion of each claim that is disposed before the terms "the improvement" 
and sets forth what is believed to be new in each claim according to this 
invention in the portion of each claim that is disposed after the terms 
"the improvement" whereby it is believed that each claim sets forth a 
novel, useful and unobvious invention within the purview of the Patent 
Statute.