Modular pipe formation apparatus

Abstract

A modular plastic pipe formation apparatus to extrude plastic pipe is disclosed and includes a plurality of modules each having a transportable container and at least one component of the pipe formation apparatus located therein. The plurality of modules are aligned in a predetermined manner during formation of plastic pipe with the components aligned for pipe extrusion. The apparatus may also include a closed circuit fluid cooling system to provide cooling fluid to some of modules to cool the pipe being formed, the cooling circuit may flows in a counter direction to the direction of pipe forming in the pipe formation apparatus.

Claims

1. A modular plastic pipe formation apparatus to extrude plastic pipe comprising a plurality of modules in the form of transportable containers wherein each module comprises at least one component of a pipe forming apparatus located therein, the apparatus further comprising a closed circuit fluid cooling system to provide cooling fluid to at least some of the plurality of the modules; the closed circuit fluid cooling system comprising a further module in the form of a transportable container, and a hot water storage tank, a cold water tank and a heat exchanger housed within the further module, wherein the cooling circuit system has an inlet port to the further module from a first of the at least some of the plurality of modules and an exit port from the further module to a second of the at least some of the plurality of modules and wherein the cooling fluid flows through the at least some of plurality of the modules in a counter direction to a direction of pipe forming in the pipe formation apparatus.

2. A modular plastic pipe formation apparatus according to claim 1, wherein the modules that receive fluid from the fluid cooling circuit system are cooling modules that are arranged to receive and cool extruded plastic pipe that passes therethrough.

3. A modular plastic pipe formation apparatus according to claim 1, further comprising a cooling arrangement to cool the fluid in the cooling circuit system.

4. A modular plastic formation apparatus according to claim 3, wherein the cooling arrangement comprises a chiller fluid circuit, both the fluid of the cooling circuit system and the chiller fluid circuit pass through the heat exchanger to cause cooling of the fluid in the fluid cooling circuit system.

5. A modular plastic formation apparatus according to claim 4, wherein the cooling arrangement further comprises a pre-cooling arrangement that cools heated fluid in the fluid cooling circuit system prior to introduction into the heat exchanger.

6. A modular plastic pipe formation apparatus according to claim 1, wherein the transportable container of at least one of the plurality of modules and the further module comprises: i.a standardised shipping container modified for use in the apparatus; or ii.a container or supporting framework for use in the apparatus and having at least some of the features of a standardised shipping container to facilitate its transportation.

7. A modular plastic pipe formation apparatus to extrude plastic pipe comprising a plurality of modules in the form of transportable containers wherein each module comprises at least one component of a pipe forming apparatus located therein, the apparatus further comprising: a closed circuit fluid cooling system to provide cooling fluid to the at least one component of more than one of the plurality of modules, the fluid cooling system comprising a further module in the form of a transportable container, and a hot water storage tank, a cold water tank and a heat exchanger housed within the further module, the cooling circuit system having an inlet port to the further module from a first of the more than one of the plurality of modules and an exit port from the further module to a second of the more than one of the plurality of modules; and a cooling arrangement to cool the fluid in the closed circuit fluid cooling system, the cooling arrangement comprising a chiller fluid circuit and a pre-cooling arrangement, wherein both the fluid of the cooling circuit system and the chiller fluid circuit pass through the heat exchanger to cause cooling of the fluid in the fluid cooling circuit system and the pre-cooling arrangement is arranged to cool heated fluid in the fluid cooling circuit system prior to introduction into the heat exchanger.

8. A modular plastic pipe formation apparatus according to claim 7, wherein at least one of the plurality of modules comprising a cooling tank as one component of that module.

9. A modular plastic pipe formation apparatus according to claim 7, wherein the modules that receive cooling fluid are provided in series to receive extruded plastic pipes therein for cooling.

10. A modular plastic pipe formation apparatus according to claim 7, further comprising a chiller to chill the fluid in the chiller fluid circuit.

11. A modular plastic formation apparatus according to claim 10, wherein the chiller is separate to the further module of the fluid cooling system.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Notwithstanding any other forms which may fail within the scope of the apparatus, system and method as set forth in the summary, specific embodiments will now be described in which:

(2) FIGS. 1a-1b are plan views of a modular plastic pipe formation apparatus according to a first embodiment;

(3) FIGS. 2a-2b are side views of the modular plastic pipe formation apparatus of FIG. 1;

(4) FIG. 3 is a plan view of a modular plastic pipe formation apparatus according to a second embodiment;

(5) FIG. 4 is a side view of the modular plastic pipe formation apparatus of FIG. 3;

(6) FIG. 5 is a plan view of the modules of the plastic pipe formation apparatus of FIG. 3;

(7) FIG. 6 is a side view of the modules of the plastic pipe formation apparatus of FIG. 3;

(8) FIG. 7 is an end view of a module of the plastic pipe formation apparatus of FIG. 3 with the end doors mounted for transportation;

(9) FIG. 8 is a sectioned view of a module of the plastic pipe formation apparatus along section B-B in FIG. 6;

(10) FIG. 9 is a sectioned view of a module of the plastic pipe formation apparatus along section C-C in FIG. 6;

(11) FIGS. 10a-10c illustrate the top (FIG. 10a), side (FIG. 10b) and sectioned end view (FIG. 10c) of a first module of FIG. 5;

(12) FIGS. 11a-11e illustrate the top (FIG. 11a), side (FIG. 11b) and sectioned end view (FIG. 11c) of a second module of FIG. 5;

(13) FIGS. 12a-12c illustrate the top (FIG. 12a), side (FIG. 12b) and sectioned end view (FIG. 12c) of a third module of FIG. 6;

(14) FIGS. 13a-13c illustrate the top (FIG. 13a), side (FIG. 13b) and sectioned end view (FIG. 13c) of a fourth module of FIG. 6;

(15) FIGS. 14a-14c illustrate the top (FIG. 14a), side (FIG. 14b) and sectioned end view (FIG. 14c) of a fifth module of FIG. 6;

(16) FIGS. 15a-15c illustrate the top (FIG. 15a), side (FIG. 15b) and sectioned end view (FIG. 15c) of a sixth module of FIG. 6;

(17) FIGS. 16a-16c illustrate the top (FIG. 16a), side (FIG. 16b) and sectioned end view (FIG. 16c) of a seventh module of FIG. 7;

(18) FIGS. 17a-17b illustrate the top (FIG. 17a) and side view (FIG. 17b) of an external support for the modules;

(19) FIGS. 18a-18b illustrate the top (FIG. 18a) and side view (FIG. 18b) of an internal support frame;

(20) FIG. 19 schematically illustrates a closed-circuit cooling water supply for the plastic pipe formation apparatus;

(21) FIG. 20a illustrates the top view of the cooling circuit unit of FIG. 19; and

(22) FIG. 20b schematically illustrates the cooling circuit unit of FIG. 19.

DETAILED DESCRIPTION

(23) FIG. 1 illustrates a plan view of a modular plastic pipe formation apparatus 1 configured for smooth wall pipe production such as HDPE pipe. The pipe formation apparatus 1 comprises a series of modules 3, each comprising modified shipping containers, within which are disposed components of the pipe formation apparatus. The modules 3 are coupled to each other in a predetermined layout, allowing the components therein to be aligned for pipe production.

(24) In the first module 5, there is provided a raw material dryer 7, screw extruder 9 and a die head 11. In the second module 15, there is provided a vacuum water tank 17. The third and fourth modules 19 house water cooling tanks 21. The fifth module 23 houses a haul off caterpillar, and the sixth module 27 houses a cutter 29.

(25) In the embodiment shown in FIG. 1a, the third, fourth and fifth modules (19a, 19b, 19c) are cooling modules including cooling tanks 21. The sixth module 23 houses a haul off caterpillar and a cutter 29. The apparatus 1 also includes workspaces 27.

(26) Other components for pipe production may include, a raw material feeding and storage component 31, a cooling circuit unit 24, a power generation unit 33, a chilling unit or chiller 35, pipe sliding table/tipping table 37 and a pipe coiler 39.

(27) In pipe production, power and water is supplied to the first module 5 from the power generation unit 33 and cooling circuit unit 24. Raw plastic material is fed from the raw material feeding and storage component 31 to the raw material dryer 7, where the raw plastic material is dried before feeding into the hopper of the screw extruder 9. The raw plastic material is then heated and pressurised in the barrel of the screw extruder 9, thereby creating a polymer resin in a molten state. The molten polymer is then forced through the die head 11, thereby creating a pipe extrusion. The hot pipe extrusion enters and is drawn into vacuum water tank 17, where the vacuum assists in pulling the extrusion from the die head. A series of water spray nozzles within the vacuum water tank 17 sprays water to cool the newly extruded pipe, to aid in solidification.

(28) To assist in passing the extruded plastic pipe through the pipe formation apparatus 1, the haul off caterpillar 25 pulls the solidified pipe from the water cooling tanks 21 and passes the pipe through the cutter 29. The cutter 29 cuts the pipe at intervals as selected by the operator, to provide pipe of desired length.

(29) The finished pipe is then transferred to a pipe sliding table/tipping table 37 where the pipe is prepared for storage and/or transportation. For flexible pipes, this may include coiling the pipe on the coiler 39 as illustrated in FIGS. 1 and 2. For larger diameter pipes that cannot be coiled, the pipe may be lifted directly from the pipe sliding table/tipping table 37 to a storage area or a pipe transporter.

(30) The components of the modules 3 will now be described in further detail.

(31) The raw material feeding and storage component 31 comprises portable silos 41, e.g. of 10 to 50 tonne capacity. As illustrated in FIG. 2, the silo 41 may be tilted such that the raw material flows to the rear of the silo 41 to assist in extraction of the raw material. The raw material is extracted from the silo by pipe work or flexible hose with a suction unit, thereby sucking the raw material from the silo, and supplying it to bulker bags 43 for temporary storage before feeding to the raw material dryer 7.

(32) The raw material dryer 7 dries the plastic raw material before feeding into the extruder 9. The raw material dryer may utilise power and heat from the power generation unit 33. Additionally or alternatively, hot air may be extracted from inside the freshly extruded pipe, and recycled to the raw material dryer 7 for drying of the plastic raw material. This can conserve energy by reducing or eliminating additional energy requirements for drying the raw material.

(33) The extruder 9 may be a single or double screw extruder. This may be a commercial off-the-shelf unit, or a modified unit with reduced total output power to match the power generation unit 33. A suitable extruder may include extruders manufactured by BATTENFELD-CININNATI GmbH. Located with the die head 11, is a pipe head. The pipe head may have the ability to produce single, double or triple layer pipe. Various pipe sizes may be produced, including 400 mm, 630 mm, 1200 mm and 1600 mm diameter pipe.

(34) Extruder line colourer 12, applies coloured lines to the extruded pipe for pipe marking and identification purposes. Although only one extruder line colourer 12 is illustrated, in other embodiments, more than one extruder line colourer 12 may be used. As illustrated in FIG. 1, the extruder line colourer 12 when configured for use, projects from the first module 5. Thus, an additional container 13 may be arranged adjacent to first module 5 to provide overhead protection to the extruder line colourer 12. Furthermore, container 13 may provide a working shelter for operators of the apparatus 1 whilst allowing them access to components of the apparatus 1.

(35) The vacuum water tank 17 comprises a cylindrical tank in which the recently extruded pipe passes through. Inside the tank is a series of water sprays to cool the hot extruded plastic pipe. The ends of the cylindrical tank are provided with a rubber boot or flaps. The rubber boot or flaps permit the extruded pipe to enter the tank and at the same time forms an atmospheric seal between the inside of the tank and the surrounding atmosphere. Vacuum pumps are disposed below the cylindrical tank to provide a vacuum inside the cylindrical tank. Water and power to the tank is provided by a respective water and electrical circuit, which will be described further below.

(36) The cooling water tanks 21, comprise a cylindrical tank provided with water sprays similar to the vacuum water tank 17. It would be appreciated that it is possible to use multiple vacuum water tanks 17 in place of the cooling water tanks 21.

(37) The haul off caterpillar 25, comprises powered caterpillar tracks that grip the outer surface of the finished pipe to pull the pipe from the cooling tanks 21.

(38) The cutter 29 and coiler 39 may be commercial off-the-shelf units. Ideally, the coiler 39 coils pipe with low ovality or deformation, such as the Low Ovality Technology coilers manufactured by PIPE COIL TECHNOLOGY LIMITED, UK.

(39) The pipe sliding table 37 is adapted to receive and support cut pipe from the cutter 29, and may comprise rollers to assist in sliding. Alternatively, or in conjunction, a tipping table may be used to receive, and transfer sections of cut pipe to a pipe trolley, or other component.

(40) The power generation unit 33, comprises either a diesel, petrol or gas generator disposed at a 20 or 40 foot shipping container. The container may further include a fuel tank for the generator. The module containing the power generation unit 33 may be adapted for outdoor or indoor use where it may be fitted with breather and exhaust piping.

(41) Power from the power generation unit 33 is provided to the first module 5, where it is distributed to subsequent modules 3 of the apparatus 1. Each module 3, will have electrical power connectors to receiver power from a module, as well as distributing power to another connected module. That is, the first module 5 will be electrically connected to the second module 15, which in turn is electrically connected to the third module 19, etc. Advantageously, this reduces the need to connect each individual module 3 with an electrical power line from the power generation unit 33, and simplifies assembly of the pipe formation apparatus 1 at the production site. An exception is power supply to the chilling unit 35, where it may be advantageous to directly connect power from the power generation unit 33.

(42) Alternatively, for production sites where electrical mains power is available, the apparatus 1 may receive electrical power from the mains source. Similar to the above mentioned embodiment, electrical mains power can be provided to the first module 5, where it will be distributed to subsequent modules 3.

(43) The water chilling unit 35 may comprise an absorption refrigerator or a compressor refrigerator inside a 20 or 40 foot shipping container. The container may further include a water tank, and the water chilling unit may be adapted for outdoor or indoor use. Optionally, the water chilling unit may be connected to, or co-located with, the power generation unit 35.

(44) The water chilling unit 35 is piped to the first module 5, and cools water for a closed circuit water supply for the apparatus 1. The water circuit comprises a cool water line and a hot water line running parallel to modules 5, 15 and 19. The modules 5, 15 and 19 have height adjustable hot and cold pipes disposed therein, and the pipes are coupled to each other to form part of the closed water circuit. The closed water circuit provides water to the water cooling tanks 21, vacuum water tank 17, and components in module 5.

(45) Alternatively, for production sites with an existing water circuit, the apparatus 1 may exchange cool and hot water with the existing water circuit. Similar to the water circuit described in the embodiment above, the water circuit can be connected to the first module 5, where it will be coupled to the pipes of subsequent modules 3.

(46) Optionally, a corrugator, either disposed in the first module 5, or in a separate module, may be positioned between the die head 11 and the vacuum water tank 17. The corrugator may be a commercial off-the-shelf system, such as the DROSSBACH HD series manufactured by DROSSBACH GmbH, or ITIB corrugator series manufactured by ITIB MACHINERY INTERNATIONAL S.p.A. The corrugator, in use, moves back and forth axially to the extruded pipe. In an embodiment, part of the corrugator may envelope part of the die head 11. In a further embodiment, part of the corrugator may protrude from a corrugator module and into the first module 5. Alternatively, the die head 11 may extend from the first module 5, and protrude into the corrugator module.

(47) Generally, each module 3 is provided with a lock 45 to allow adjacent modules 3 to be locked to one another. This ensures the modules are correctly arranged with respect to each other during pipe formation. Furthermore, an adjustment mechanism such as a winch may be used for pulling modules together. Thus, modules can be placed in close proximity to each other, and the winch may then pull modules together before the locks 45 are engaged.

(48) The components within each module 3 are also adjustable in position or angle with respect to the module they are disposed in. In one form, the components are supported by adjustable jacks on top of the module floor. Adjustment may either be mechanical, hydraulic, electro-mechanical or, by other suitable actuation means. Furthermore, actuation may be automated or semi-automated, and controlled by a computer. The adjustability of components within each module allows alignment of the components when the modules themselves are not perfectly aligned.

(49) A referencing laser may be used to determine the relative positions of the modules 3 or components, and provide information to allow corrections to the position of the modules 3 or components therein. The laser may be set up at either or both ends of the apparatus 1, with the laser directed co-axially to the pipe extrusion axis.

(50) In one embodiment, witness panes in the path of the laser beam may be attached to the components and/or modules. The location of the laser reflection on the panes will thus provide information on the position of the components and/or modules relative to the reference laser. It should be appreciated that other methods of alignment may be used (e.g. sight gauges).

(51) The modules 3 are generally modified 20 foot or 40 foot shipping containers. In one form, the sides or top of the modules may have doors to allow ventilation during pipe formation. In another form, the modules may be an open frame, and the top and/or sides may simply be left open during transportation, or covered with a tarpaulin.

(52) A second embodiment of the modular plastic pipe formation apparatus 101 is illustrated in FIGS. 3 to 16. Features corresponding to those presented previously discussed are similarly numbered with “100” preceding the similar feature.

(53) In the apparatus 101 of the second embodiment, the raw material dryer 107 is contained in a separate first module 105. The second module 106, contains the screw extruder 109 and the die head. The third module 115, fourth module 119 and fifth module 120 contain vacuum water tanks 117 and/or water cooling tanks 121. The sixth module 123 contains a water cooling tank 121 and a haul off caterpillar 125. The seventh module 127 contains a cutter 129 and a second haul off caterpillar 126. A second haul off caterpillar assists in pulling longer pipes.

(54) The modules 103 of the apparatus 101 generally comprise modified 20 foot and 40 foot containers. The modules 103 are supported by external supports 151, comprising adjustable jacks 153 supported by screw piles 155 driven into the ground.

(55) The external support 151 is shown in more detail in FIG. 17. The screw pile 155 is selected from a type, size and length suitable to support the weight of the modules 103 for the underlying ground. The adjustable jack 153 comprises of a top plate 157, bottom plate 153 and adjustment bolts 161. The adjustment bolts 161 allow adjustment of the height of the supported modules 103. The top plate 157 is sufficient span to support two adjoining modules at their respective ends as illustrated in FIG. 6. However, it is to be appreciated that additional external supports 151 may be used at locations along the intermediate length of the modules 103 as required. Furthermore the span of the top plate 157 also enables a degree of lateral displacement to enable adjacent modules 103 to be aligned.

(56) Advantageously, the external supports 151 elevate the modules 103 above the underlying ground which assists in drainage if the apparatus 101 is located outdoors. Furthermore, the use of piles reduces the need for a flat hard surface to support the modules. Thus, less preparation is required at the pipe manufacturing site. In addition, the apparatus may be set up in areas with poor ground soil quality (e.g. softer, sandy, loamy, uncompacted, etc soil or ground).

(57) An internal support frame 163 for supporting components within a module 103 is best illustrated in FIG. 18. The support frame 163 comprises a frame body 165 and adjustable locking mounts 168. The adjustable locking mounts 168 are mountable to the floor reinforcements 167 on the floor of the modules 103. The adjustable locking mounts 168 enable the frame to be linearly and angularly displaced as required to ensure the components in the modules 103 are aligned.

(58) The modules 103 will now be described with reference to FIGS. 5 to 16. As illustrated in FIG. 7, the modules are reduced to standard shipping container sizes during transportation. This may include attaching removable container doors 171. The doors 171 are typically removed before assembly of the apparatus 101.

(59) FIG. 8 illustrates a sectioned view of module 106, as an example of an open in-use configuration of a module 103. The module 106 has a fold down side wall 173, which folds down to rest on an external support 151. The fold down side wall 173 can then function as a floor for technicians to access the apparatus 101.

(60) The module 106 is also provided with an open top section 175. This allows components of the apparatus 101 to extend above the top section of the module 106 when configured for use. This also advantageously improves ventilation within the module. To ensure the apparatus is protected from weather, including rainwater and dust, a surrounding canvas awning 177 is provided above and around the open top section 175, extending to the fold down side wall 173. This ensures the technicians as well as the components are protected from external elements. FIG. 9 illustrates an alternative awning 178, where the awning extends outwardly from the top of the module 127.

(61) Between the ends of each module 103 there is provided a rubber concertina-like boot. This ensures a weather, water and dust proof seal between adjoining modules 103. The boot may be attached to each end of the module 103 by bolts.

(62) On the modules 103 has enclosed tops. The tops may be angled toward the longitudinal centre of the module, and to one side. This ensures drainage of rainfall is directed away from the boot sealing the ends of the adjacent modules 103, thus reducing the chance of water leaking into the modules 103.

(63) The modules 103 are provided with ventilation louvers 179 to assist in ventilation of the apparatus 101. Furthermore, air-conditioning units 181 may be provided to regulate the temperature within the apparatus 101.

(64) Between modules 106 and 115, the vertical beams 183 and 185 at the adjoining ends may be removable. This facilitates access to the die head which is located in the region of the adjoining ends. To maintain structural integrity of the modules 106 and 115, an additional vertical beam may be located at an alternative location.

(65) To establish a mobile plastic pipe formation site, a suitable site is first located. The site may be outdoors in the open, under covered shelter, or indoors. Generally, a flat ground, at least the size of the apparatus is required. The ground can be a hard surface, such as bitumen or concrete. Alternatively, a screw pile and adjustable jacks may be used to support the modules. This latter approach is especially suitable for softer ground. The modules, in the form of transportable containers are delivered to the site. Since the containers have features of standard 20 or 40 foot containers, existing transportation and handling equipment can be used.

(66) Once the modules 3 are transported to the production site, the modules may be configured from their transportation state to a pipe production state. This may include opening and/or removing the container doors 171, and removing any packing or protective equipment required during transportation.

(67) The modules 3 are then arranged as required in the predetermined manner at the production site. The modules 3 are then drawn into close proximity with each other using a winch, and then locked together.

(68) Alternatively, two modules are first arranged in the predetermined manner (above) at the site. The two modules are then drawn to close proximity using a winch, and then locked together. A further module is then arranged as required in the predetermined manner. The further module is then positioned in close proximity to the first two modules that have been locked. The further module is then drawn towards the first two modules with a winch, and then locked. This can be repeated until all modules required have been arranged and locked as required.

(69) When all the modules have been arranged and locked, the components supported by the modules may then be adjusted in position and aligned to each other. As described above, this may be done manually or autonomously, and may be aided with a reference laser.

(70) The electrical connectors and the coupling for the water pipes between each module 3 are then connected, to provide power and water for the modules. Once this is completed, and water, power and raw plastic materials are supplied to the apparatus 1, the plastic pipe formation site is established and pipe formation operations can commence.

(71) FIG. 19- to 20b disclose a further embodiment of closed circuit water supply 150 for the modular pipe formation apparatus 1, 101 which provides for more efficient power and water usage. For convenience, like features use the references of the first embodiment of the apparatus 1, but the further embodiment disclosed is equally applicable to the second embodiment of apparatus 101.

(72) In the illustrated embodiment of the closed-circuit cooling water supply 150, the water chilling unit 35 is connected by piping to the cooling circuit unit 24. Water from the chilling unit 35 flows into the cooling circuit unit 24 and circulates therebetween. The cooling circuit unit 24 in turn distributes cold water (cooled by interaction with the water from the chilling unit) through the closed-circuit water supply 150 to modules 3 in the modular plastic pipe formation apparatus 1. The arrangement and method of cooling the pipe extrusion is described in further detail now.

(73) The closed-circuit cooling water supply 150 is shown schematically in FIG. 19. The cooling circuit 150 incorporates the cooling circuit unit 24 wherein water passing through the circuit is stored, cooled, treated, and pumped into the circuit 150. The cooling circuit 150 flows in a counter direction to the direction of pipe formation and as shown the water from the unit 24 is piped to the cooling module 19c then by coupling in sequence, is distributed through subsequent modules 3 of the apparatus 1, i.e. the cooling module 19c will be connected to the cooling module 19b, which in turn is connected to the third cooling module 19a, connected to the vacuum tank 17.

(74) Water is cycled through the closed-circuit water supply 150 by entering the module 19c from the cooling unit 24, at about 15 degrees Celsius. The water flows in a direction opposite to the pipe extrusion moving through modules 3. The water flows in sequence from one module to the next, increasing in temperature by approximately 10 degrees Celsius to where it finally exits the module 17 at about 60 degrees Celsius. At this final stage, the water is substantially heated and is to be cooled before re-entering the module 19c to complete the closed-circuit.

(75) The heated water in the closed-circuit supply 150 is cooled by various methods. As shown schematically in FIG. 19, three processes may be involved. A first process is by using the waste heat in the pipe formation apparatus (e.g. drying the raw material, heating the injection barrel of the pipe extruder). A second process is by exposure to ambient temperature or other external environments. The third process is by interacting with the chiller unit fluid which happens via a heat exchanger arrangement in cooling circuit unit 24. The cooling circuit unit 24 will now be described in further detail.

(76) As shown in FIG. 20a, the cooling circuit unit 24 is typically housed within one of the modules 3, typically being a transportable container 201. The circuit 24 includes heat exchangers 204, hot water storage tanks 202, cold water storage tanks 208 and water treatment units 206. The heat exchangers are connected to the water supply circuit 150 and a chiller circuit that allows chilled water from chiller 35 to pass into the heat exchanger through inlet port 207 exit through outlet port 210 to cool the heated water returning in circuit 150. In one illustrative form, water exiting the vacuum tank 17 is a approximately 60 degrees Celsius and may be utilized in a waste heat capture process where after it enters the cooling circuit unit 24 through port 209 and is stored in hot water storage tank 202 before entering heat exchanger 204. When in the tank 202, the water is able to cool further. Typically, the water temperature entering the heat exchanger may be in the order of 40 degrees Celsius. The chiller 35 circulates cold water at approximately 8 degrees Celsius into the heat exchangers 204 where it cools water circulating through the closed-circuit water supply. Water in the closed-circuit water supply then passes through a water treatment process, i.e., water softening, and is then stored in the cold water storage tank 208 before it is recirculated through the series of modules 3, via port 211. Water exiting the free cooling unit 24 is approximately 15 degrees Celsius.

(77) This arrangement of sequential flow through modules 3 inherently reduces the volume flow of cooling liquid through apparatus 1 as compared to if the modules were connected into the circuit in parallel. This is advantageous for the conservation of space for holding water tanks in the small confines of the module 3. Another main advantage is that the energy used in cooling the pipes is significantly reduced. It has been found that the energy used by the chiller can be reduced as the heat that needs to be removed from the water by the chiller may be reduced by 80% (in tests conducted by the applicant the heat requiring removal reduced from 20.6 kW to 0.8 kW) because of the ability to use the waste heat in the heated water supply and through passive cooling.

(78) In any of the forms of modular pipe formation apparatus described above, hen plastic pipe formation at the site is complete, the pipe formation apparatus can be moved to a new site. This involves decoupling the electrical connectors, water pipes and modules. The modules are then configured to a transportable state, such as attaching and/or closing doors, adding packing or protective equipment, and adjusting position of components so they fit within the shipping container dimensions. The modules may then be transported to the new production site, and the method of establishing a plastic pipe formation site described above is repeated.

(79) In projects where a long continuous pipeline is required, the plastic pipe formation apparatus may be intermittently moved along the proposed pipeline as the pipe is laid. That is, a first mobile pipe manufacturing site is located near the start of the pipeline, and pipe is formed, transported and the pipe laid. As the front of the pipe laying site advances forward, the formed pipe needs to be transported further from the pipe manufacturing site to the pipe laying site. Thus, the time and cost of transportation of pipe increase. It may then be economical to relocate the pipe formation apparatus 1 to another site closer to the advancing pipe laying site, or even ahead of it. Alternatively, a second pipe formation apparatus can be located at the new site, with the first apparatus being readied for a third site, etc. Thus the apparatus provides a mobile pipe manufacturing site which advantageously allows pipe production to keep up with the pipe laying site.

(80) In the claims which follow and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the apparatus, system and method.

(81) It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.