Apparatus for installing a flexible cured in place lateral seal in an existing main pipeline

An apparatus for installing a cured in place lateral seal in an existing main pipeline wherein the lateral seal includes a brim portion bonded to a short tubular portion is provided. The apparatus includes a flexible bladder mounted on a cylindrical housing with the bladder having a recess with an inflatable arm which can be tucked within the housing for receiving the tubular portion of the seal with the brim portion along the outer portion of the bladder. The cartridge is removably mountable on a sled or robot device with positioning motors for positioning the seal at the opening of the lateral pipeline. The use of replaceable bladder cartridges allows an operator to load a second new seal on a cartridge a first seal on a bladder cartridge mounted on the sled is being cured in place.

BACKGROUND OF THE INVENTION 
This invention relates to an apparatus for the installation of a flexible 
lateral seal which is impregnated with a curable resin, and more 
particularly to an apparatus having a silicone bladder with a cavity for 
receiving the flexible lateral seal and which can be inflated to form a 
seal along the main pipeline and invert the lateral seal into the lateral 
pipeline from the main pipeline. 
The most widely practiced method of lining existing pipelines and conduits 
using a flexible resin impregnated lining or "cured in place pipe" is the 
Insituform.RTM. Process and is described in U.S. Pat. Nos. 4,009,063 and 
No. 4,064,211, the contents of which are incorporated herein by reference. 
Briefly, in the Insituform.RTM. Process, an elongated flexible tubular 
lining of a resin impregnable material, such as a needled felt, which has 
been impregnated with a thermosetting synthetic resin, is installed within 
an existing pipeline that is in need of repair. The impregnated liner may 
be pulled into the conduit by a rope or cable, and a fluid-impermeable 
inflation bladder or tube is then everted within the liner as described in 
detail in U.S. Pat. No. 4,009,063. Alternately, the liner is installed 
utilizing an eversion process as described in U.S. Pat. No. 4,064,211. The 
liners utilized in the Insituform.RTM. Process are flexible and generally 
have a smooth impermeable coating on one side. After inversion, this 
smooth layer becomes the inside of the liner. 
After the flexible liner is positioned within the conduit, the liner is 
pressurized from within, preferably using a fluid such as water. The fluid 
pressure forces the liner radially outwardly to engage and conform to the 
interior surface of the existing pipeline. The resin is then cured by 
recirculating heated water to form a relatively hard, tight-fitting rigid 
pipe lining that effectively relines the existing pipeline. In addition to 
curing by heat, the resin can be cured using other forms of radiant 
energy, such as ultra violet light as described in U.S. Pat. No. 4,135,958 
or visible light in U.S. Pat. No. 4,518,247 and U.S. Pat. No. 4,680,066, 
the contents of which are incorporated herein by reference. Alternatively, 
radiant energy in the form of electrical energy or sound waves can be used 
to initiate the cure. Once the liner is completely cured, lateral 
connections are cut to existing services to the liner by remote cutters, 
which are common expedients in the art. 
There is a strong demand and a need to seal the connections between the 
main conduit and any lateral pipes, in addition to the repair of the main 
pipeline. This is an important consideration in the process of relining an 
entire existing sewer system in order to effectively prevent the ingress 
of ground water into the system and outflow of effluent from the system. 
In a typical municipal sewer system, there are a plurality of lateral 
pipeline entering a main conduit between adjacent manhole access points. 
The time needed to cure a cured in place liner that has been installed in 
a main pipeline is typically between four and six hours. Using existing 
methods of lining or lateral pipelines or is not possible to perform any 
significant repair or lining operations of the plurality of lateral 
connections at the same time that a main conduit is being lined. Repair or 
sealing of each lateral connection using conventional lining methods is 
difficult. Such long cure times would generally increase the amount of 
time required to complete the repair of a particular line by almost a full 
day of work for each lateral connection. Since a typical residential 
street may have about ten or more homes between manholes, this would 
increase the operating time needed to complete the lining operation for 
repair of the main pipeline between adjacent manholes from one day to ten 
days or more. 
There are presently several proposals available for lining lateral 
pipelines and forming a seal at the lateral connection. Some of these call 
for lining the lateral from the outlet of the service lateral inward to 
the mainline conduit. One such method is described in U.S. Pat. No. 
5,108,533. Others utilize a launcher-type apparatus that inserts a lining 
from the main pipeline into the lateral connection at a location remote 
from the access to the main pipeline. This process is described in U.S. 
Pat. No. 5,624,629, the contents of which are incorporated herein by 
reference. Here, a second or subsequent lateral is lined and cured, at the 
same time as an initial lateral is being lined in an effort to reduce the 
overall time of repair of the system. However, because several laterals 
are typically connected to a particular mainline conduit, it is difficult 
and almost physically impossible to install lateral seals at more than one 
location within a mainline conduit at the same time. 
Accordingly, it is desirable to provide a device suitable for installation 
of a flexible lateral seal at the intersection between a lateral pipeline 
and a main pipeline which can be efficiently operated from a remote 
location for providing installation from the mainline into the lateral. It 
is desirable to improve the speed and cycle time required to install a 
lateral seal in order to provide truly cost effective repair of lateral 
intersections. 
SUMMARY OF THE INVENTION 
Generally speaking, in accordance with the invention, an apparatus for 
installing a cured in place lateral seal having a brim portion bonded to a 
short tubular section is provided. The apparatus includes a cartridge 
assembly having a cylindrical flexible bladder with an extendible arm 
which can be tucked into the bladder to form a recess for receiving the 
tubular portion of the seal with the brim seated on the outer portion of 
the bladder. The cartridge assembly is removably mounted on a sled or 
robot device with positioning motors for positioning the seal at the exact 
location of the lateral. Use of a replaceable cartridge allows the 
operator to load a new seal wetted with curable resin on a cartridge as 
another seal on the sled is being cured in place for rapid exchange. 
The bladder is secured to the ends of a cylindrical hollow frame to form a 
cartridge assembly which has an inlet for introduction of pressurized 
fluid for inflating the bladder to press the brim portion of the seal 
against the interior of the main pipeline and everting the arm and tubular 
portion of the seal out of the recess into of the lateral to form the 
lateral seal. The cure can be initiated by introduction of heated fluid or 
electrical power for powering radiant energy source within the bladder 
such as light energy, either UV or visible, sound or microwaves. 
The sled includes on at least one end a lift motor to place the brim 
portion of the lateral seal on the surface of the main pipeline at the 
lateral opening. It may include separately operable lift motors at both 
end of the cartridge. The sled may also include at least one rotational 
motor for rotating the cartridge circumferentially to align the brim of 
the seal with the lateral opening. 
Accordingly, it is an object of the invention to provide an improved device 
for installing a flexible cured in place lateral seal into the junction 
between a main pipeline and lateral connection from inside the main 
pipeline. 
Another object of the invention is to provide an improved device for 
installing a flexible cured in place lateral seal, including a cartridge 
holding the resin impregnated lateral seal which can be replaceably 
mounted on a delivery sled for assembly. 
A further object of the invention is to provide an improved bladder 
cartridge for insertion into a delivery sled for the rapid installation of 
flexible cured in place lateral seals from the mainline of an existing 
conduit. 
Still another object of the invention is to provide an apparatus for the 
installation of a curable resin lateral seal providing a source of radiant 
energy with a bladder assembly. 
Yet another object of the invention is to provide a bladder apparatus for 
the installation of a light curable resin lateral seal providing a source 
of curing light within the bladder apparatus. 
Still other objects and advantages of the invention will in part be obvious 
and will in part be apparent from the specification. 
The invention accordingly comprises the several steps and the relation of 
one or more of such steps with respect to each of the others, the 
apparatus embodying features of construction, combination(s) and 
arrangement of parts which are adapted to effect such steps, and the 
product which possesses the characteristics, properties, and relation of 
constituents (components), all as exemplified in the detailed disclosure 
hereinafter set forth, and the scope of the invention will be indicated in 
the claims.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
An apparatus 101 for installing a lateral seal 11 at the intersection 
between an existing main pipeline 21 and a lateral pipeline 22 is shown in 
FIG. 3. In this particular case, main pipeline 21 has previously been 
lined with a cured in place lining 23 utilizing the Insituform Process. It 
is possible to utilize the apparatus for installing seal 11 to seal the 
connection in a main pipeline which has not been relined. Alternatively, 
main pipeline 21 may have been lined utilizing other trenchless technology 
processes, commonly referred to as fold and formed, diameter reduction, or 
slip lining and the like. 
Referring specifically to FIG. 1, seal 11 includes a substantially flat 
brim 12 bonded to a relatively short tubular section 13. Brim 12 is formed 
of a resin impregnable layer 14 and an impermeable layer 16 bonded 
thereto. Tubular portion 13 is bonded to brim 12 by a compatible adhesive, 
a hot melt material or flame bonding. 
Tubular portion 13 is formed from a substantially planar piece of resin 
impregnable lining material 15 coated on one side with an impermeable 
layer 20 which has been joined together edge to edge in a butt seam 
relationship with a row of stitches 18 to hold the edges together. A band 
of impermeable material 19 in the form of a tape or quantity of an 
extruded material is placed over stitches 18 to maintain the impermeable 
characteristics of impermeable layer 20. 
Brim 12 formed from a substantially planar resin impregnable material 14 is 
also coated on one side with an impermeable layer 16 dimensioned to 
conform to the opening between lateral 22 and main pipeline 21. Typically 
lateral 22 may intersect main pipeline 21 at a 60.degree. angle as 
illustrated in the completed installation in FIG. 2. However, laterals may 
be found to intersect a main pipeline at angles of 45.degree. and/or 
90.degree.. In these cases, the opening between the lateral and mainline 
will vary, depending on the angle and relative size of the pipelines. This 
can be determined during the prepatory inspection and video steps in the 
rehabilitation so that custom made lateral seals 11 can be fabricated as 
needed. A guide line 24 is provided on impregnable layer 14 of brim 12 to 
aid in the installation as will be described in more detail below. 
When a light cure resin is used to impregnate seal 11, lamps emitting 
visible light having a wave length in the range of about 300 to 500 
nanometers are mounted within a bladder cartridge 102 shown in FIGS. 3 and 
5. Resin impregnable material 16 and 18 is typically an acrylic or 
polypropylene felt or a glass fibrous matte which will transmit the 
visible light when impregnated with a modified polyester or epoxy to yield 
a resin which is light curable as discussed in U.S. Pat. No. 4,581,247, 
the contents of which are incorporated herein by reference. 
Resin 34 is a composition of a free radical light cureable resin admixed 
with an effective amount of a visible light, photo-bleaching initiator 
system and optionally performance enhancing fillers which can be 
impregnated into resin impregnable layers 17 and 22 and subsequently cured 
to a suitable depth. The resin can be selected from oligoeters of 
mono-ethylenically unsaturated urethanes, epoxies, polyesters and 
acrylics. 
In the preferred embodiments of the invention, the resin is an epoxy 
acrylate resin which is a diglycydyl ether of bisphenol A which has been 
esterified with acrylic acid or methacrylic acid and which may include an 
ethylenically mono-unsaturated compound as a viscosity modifier admixed 
with an effective amount of a photo-bleaching visible light initiator 
system. The photo-bleaching initiator system includes a visible light 
sensitizer which is a fluorone derivative admixed with a hydrogen donor 
compound. 
The visible light curable sensitizer compound includes a fluorone derived 
material. The fluorone derivative visible light sensitizer compound has 
the general formula 
##STR1## 
wherein in R.sup.1 is hydrogen, C.sub.1 -C.sub.8 alkyl, acyl and X.sup.1 
is a hydrogen atom or a halogen atom and X.sup.2 is a hydrogen atom or the 
same or different halogen atom, a benzoyl group, a group of the formula 
--L(C.sub.2).sub.n.sup.2 where n is 1 to 8 and R.sup.2 is hydrogen, 
hydroxy, amino, dialkylamino, --COR.sup.3, or --COOR.sup.4 wherein R.sup.3 
is hydrogen, chlorine, COC, C.sub.1 to C.sub.8 alkyl, aryl, COR, 2,4 
dinitrophenyl, N-imido or N.sub.2 and L is a direct bond or &gt;C=0 and R is 
hydrogen or lower alkyl, and those disclosed in U.S. Pat. No. 5,451,343. 
The preferred fluorone derivative is 5,7-diiodo-3-butoxy-6-fluorone. The 
fluorone derivative sensitizer is mixed with an electron donating 
coinitiator, such as a tertiary amine to form the photoinitiator system. 
Triethanolamine has been found to enhance the photo-bleaching effect of 
the fluorone sensitizer. 
After lateral seal 11 is installed, brim 12 sits along the interior surface 
of main pipeline 21 and will bond to previously installed lining 23. 
Tubular portion 13 extends a desired distance into lateral pipeline 22. 
This effectively seals what is generally considered to be a principal 
shortcoming in the lining of existing pipelines. In a relined sewer system 
with lateral seal 11 is installed after a cutout 29 is formed on lining 
23. Once seal 11 is installed, it will be more difficult for ground water 
at a remote fracture 31 from entering relined main pipeline 21 at cutout 
29. This is because cutout 29 is generally formed using a remote cutting 
tool with a router bit or the like leaving a rough opening. This created a 
long felt need for providing an effective lateral seal to seal the 
connection between a lateral pipe 22 and main pipeline 21. 
Lateral seal 11 can be effectively installed utilizing an apparatus shown 
generally as 101 in FIG. 3. Apparatus 101 includes a bladder cartridge 102 
including an inflatable bladder 103 mounted on a substantially rigid 
bladder frame 104 with a proximal end plate 105 and an identical cup 
shaped distal end plate 105' with side wall sections 106 and 106'. Bladder 
103 is mounted to side wall sections 106 of end plates 105. As illustrated 
in FIG. 3, bladder frame 104 carrying bladder 103 is mounted in a delivery 
sled 107 equipped with a proximal positioning motor 108 and a separately 
operable distal lift motor 109 and a TV camera 111 mounted on a motor arm 
112 by a spring 113. 
Motor arm 112 is mounted on rack of a rack and pinion lift bar 114 which is 
operably coupled to proximal positioning motor 108. Proximal positioning 
motor 108 provides lift to lift bar 114 for elevating the proximal end of 
bladder cartridge 102 at a proximal lug 117 connection at proximal end 
plate 105 and also includes a rotational motor (not shown) for rotating 
motor arm 112 radially for positioning seal 11 at the entrance to lateral 
22. Distal lift motor 109 also includes a lift arm 116 which includes a 
rack and pinion for lifting or lowering the distal end of bladder 
cartridge 102 by a distal lug connection 117' at distal end plate 105'. 
Delivery sled 107 includes a base plate 118 for supporting motors 108 and 
109. Base plate 118 is mounted on a pair of sled runners 119 at each end 
for displacement of apparatus 101 along the length of existing main 
pipeline 21 at the location of lateral 22. Positioning is facilitated by 
using TV camera 111 which is controlled remotely by a cable 120. TV camera 
111 is mounted on spring 113 to permit displacement downward as lift motor 
108 lifts bladder cartridge 102 into position adjacent to the opening to 
lateral 22. 
Proximal end plate 105 includes at least one inlet port 126 which provides 
access to the interior of bladder cartridge 102 for providing a source of 
pressure to inflate bladder 103 and power a source of radiant energy in 
the interior of bladder 103 for initiating the cure of resin impregnated 
in impermeable layer 14 and 15 of seal 11. In the illustrated embodiment, 
pressure is provided by an air/vacuum hose 126' coupled to inlet port 126. 
A power line 127' is coupled to another inlet port 127 to provide power to 
a source of radiant energy within bladder 103. Corresponding ports 128 and 
129 are provided in distal end plate 105. This is beneficial as it permits 
utilizing one port 128 to allow air to escape when the pressurized fluid 
is air. Alternately, water can also be expelled through distal output 129. 
However, this may not be wholly desirable since the portion of the main 
pipeline being lined is generally bypassed from the remainder of the pipe 
system. By providing comparable inlet and outlet ports on both proximal 
end plate 105 and distal end plate 105', bladder cartridge 102 can be 
inserted into delivery sled 107 in either direction. This greatly 
facilitates installation of laterals which intersect main pipeline 21 in 
opposed directions. 
As pressurized air is applied to the interior of bladder 103, bladder arm 
110 which was tucked within bladder 103 everts through the opening in brim 
12 of seal 11 forcing tubular portion 13 of seal 11 to evert into lateral 
22. Seal 11 is held in place as long as bladder 103 and arm 110 remain 
inflated. Generally air or water under pressure can be utilized to inflate 
bladder 103. When water is utilized and provides heat as the source of 
radiant energy for initiating the cure, an additional outlet 129 in distal 
plate 105 is used to permit the water to circulate. 
When lateral seal 11 is positioned in place and bladder 103 is inflated, 
energy is applied to initiate cure of the resin. When the energy is 
visible light as in the embodiment of FIG. 5, cool air supplied by air 
hose 126' is circulated through bladder 103. This removes the heat 
generated by the exothermic cure reaction and the substantial heat 
generated by the halogen lamps as the visible light source. An adjustable 
pressure relief valve 125, such as a Nupro B-8C pressure relief valve 
which is adjustable between 3 to 50 psi with a 1/2 inch male thread is 
mounted in port 128. By inputting air at port 126 at about 20 psi through 
hose 126' and setting valve 125 at 4 psi, 4 psi pressure can be maintained 
in bladder 103 to keep it inflated. 
At the completion of cure which can be as little as five minutes, a vacuum 
is drawn through air hose 126' now coupled to a vacuum pump to deflate 
bladder 103. Application of the vacuum to bladder 103 withdraws arm 110 
from lateral 22 and causes it to deinvert into bladder 103. Withdrawal of 
arm 110 from within seal 11 is thus accomplished without use of a rope or 
other pulling mechanism which would otherwise present an opaque region and 
cast a shadow which would interfere with light projected into lateral 22 
during the cure cycle. 
Providing bladder cartridge 102 as a separate removable unit from delivery 
sled 107 results in several significant operational advantages. This 
allows loading of a second impregnated lateral seal 11 on a second bladder 
cartridge 102 as a first is being used to install and cure at one lateral 
location. As soon as the lateral connection being installed is completed, 
delivery sled 107 is removed from main pipeline 21, spent bladder 
cartridge 102 is removed and a second bladder cartridge 102 previously 
loaded with resin impregnated seal 11 is then inserted at both lug 
connections 117 and 117' and a second lateral installation can begin 
immediately. This is a significant time saving advantage. This is 
particularly true when a visible light cure resin is used as will be 
described in connection with the most preferred embodiment below. 
A bladder frame assembly 151 fully outfitted for use in such a visible 
light lateral seal installation is shown in perspective in FIG. 7. The 
individual elements assembly 151 will now be described. FIG. 4 illustrates 
a bladder frame 152 having a substantially rigid planar base 153 and cup 
shaped end plates 154 and 156 have a sidewall 157 with projections 158 for 
a securing bladder 171 shown in FIG. 5 thereto. Each such end plates 154 
and 156 is substantially identical which allows completed bladder frame 
assembly 151 to be mounted in either direction onto sled 107. This is more 
significant when lights have been installed, particularly when laterals 
intersect the main pipeline at an angle. End plates 154 and 156 are welded 
to the end of base 153. A tubular steel skeleton frame 159 having a 
central opening 161 for providing access to the interior of bladder frame 
assembly 151 is welded between end plates 154 and 156 opposite base 153. 
End plates 154 and 156 are formed with four threaded conduit 162, 163, 164, 
and 165. These will be described in more detail with respect to the 
completed bladder frame assembly 151. These conduits are utilized for 
providing pressurized air, an air gage, an air relieve valve and air 
electrical power line, respectively. Each end plate also includes a clevis 
or mounting lug 167 which can be coupled to delivery sled 107 merely by 
passing a bolt 168 through the opening in lug 167. 
Referring now to FIG. 5, a bladder 171 specially designed for use with 
bladder frame assembly 151 is shown in perspective. Bladder 171 includes 
an elongated tubular portion 172 and an invertible flexible arm 173 
connected to the midsection for extending up into the lateral during 
operation when internally pressurized. In the case of a visible light cure 
device, bladder 171 is formed from a transparent silicone rubber material 
which permits light from lights mounted on bladder frame 152 to be 
transmitted into resin impregnable layers 14 and 15 of seal 11 and 
initiate the cure. Preferably, silicone bladder 171 transmits 25 to 65 
percent light from within. Each end of tubular section 172 remains open 
for facilitating placement of bladder frame 152 within bladder 171. 
Prior to securing bladder 171 to bladder frame 152, visible light lamps 181 
are secured to base plate 153 of bladder frame 152. When a visible light 
cure system is utilized, lamps 181 emitting visible light within the range 
of about 400 to 600 nanometers are utilized. Preferably, lamps 181 are 
1000 watt halogen lamps having a tungsten halide filament mounted with a 
substantially rectangular light box 176. These lamps emit light rich in 
the 470 nanometer region. Box 176 has a bottom 177, sidewalls 178 and a 
transparent glass top plate 179 with visible light lamps 181 positioned 
within light box 176. Matching electrical connections 182 are provided 
both ends of light box 176 so that light bladder frame assembly 151 may be 
inserted into delivery sled 107 in either direction as discussed above. 
When installing lateral seal 11 in lateral pipeline 22, such as shown in 
FIG. 2 which intersects main pipeline 21 at a wye or angle, it is 
desirable to provide sufficient light extending into lateral pipeline 22 
to insure that the resin in tubular section 13 is fully cured. In order to 
accomplish this, an additional visible light emitting lamp 183 is provided 
at one end light box 176 projecting upwardly at an angle into the location 
of lateral 22. In this embodiment, a small 300 watt projector lamp 183 is 
aimed towards the dark or short side of wye fitting. The cavity between 
light box 176 and skeleton 159 at the opposite side of light box 176 
remains free so that tubular portion 13 of lateral seal 11 can tucked 
within the interior of bladder frame 152 as seal 11 is loaded for 
installation. 
When bladder frame 152 is fully assembled, it is slipped within bladder 171 
which is then sealed by a tape or packaging band 174 as shown in FIG. 6. 
Here, arm 173 has been tucked into opening 161 in skeleton 159 of bladder 
frame 157. 
The fully constructed visible light bladder frame assembly as illustrated 
in FIG. 7 with bladder 171 secured by bands 174 is completed lateral seal 
11 is loaded for use. A fully loaded bladder cartridge 151 with seal 11 
ready for installation is illustrated in cross-section in FIG. 8. Here, 
each of the elements has been identified by the reference numerals 
utilized in connection with FIGS. 4-7. Further description of these 
elements is not necessary at this time. 
Referring now to FIG. 9, a perspective view of delivery sled 107 is shown. 
Each of the elements described in connection with FIG. 3 are identified by 
the same reference numerals herein. Delivery frame 107 includes a base 118 
having a proximal base half 122 and a distal base half 123 coupled 
together at a hinge 124. Motors 108 and 109 are positioned on respective 
base halves 122 and 123. A proximal pair of sled runners 119 are mounted 
to proximal base half 122 and a pair of distal sled runners 121 are 
mounted to distal base half 123. Mounting lugs 117 for coupling to a 
mating lug 167 on light bladder frame assembly 151 is shown on distal lift 
motor 109. 
Delivery sled 107 is fabricated with hinge 124 in order to permit insertion 
of sled 107 into a main pipeline which has restricted or limited access. 
Since delivery sled 107 with TV camera 111 and motors 108 and 109 is 
almost double the length of bladder frame assembly 151, this allows 
placement of distal end of delivery sled 107 into a main pipeline 21 when 
folded at hinge 124, retracting it from the end of the pipeline, 
flattening base 118, inserting bladder assembly 151 and then locating 
apparatus 101 within main pipeline 21 for installation of seal 11. 
Once inserted into main pipeline 21, sled runner 119 and 121 rest against 
lining 23 in main pipeline 21 as illustrated in FIG. 10. When in position 
at the entrance to lateral 22 and pressurized, bladder arm 110 or 173 
everts through tubular portion 13 of seal 11 and extends into lateral 22 
as shown in the cross-sectional view of FIG. 11. FIG. 12 illustrates the 
same view in elevation with secondary lamp 183 providing light to extend 
up into the dark or short distal region of tubular portion 13 which would 
otherwise not be illuminated by light emitted from light box 176 alone. 
It will thus be seen that the objects set forth above, among those made 
apparent from the preceding description, are efficiently attained and, 
since certain changes may be made in the above construction(s) without 
departing from the spirit and scope of the invention, it is intended that 
all matter contained in the above description or shown in the accompanying 
drawing(s) shall be interpreted as illustrative and not in a limiting 
sense. 
It is also to be understood that the following claims are intended to cover 
all of the generic and specific features of the invention herein described 
and all statements of the scope of the invention which, as a matter of 
language, might be said to fall therebetween.