Fluid conduit evacuation systems, methods, and apparatus

Abstract

A fluid conduit evacuation system including a fluid conduit having a backflow prevention device coupled thereon. A first valve is linked to the fluid conduit to control fluid flow into the conduit for passage through the backflow prevention device. An air supply device is linked to the conduit, between the first valve and the backflow prevention device, to inject air under pressure into the conduit to push any fluid within the backflow device therethrough. A method and apparatus for evacuating a conduit.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This is a national stage application of International Application No. PCT / US2024 / 016114 filed on Feb. 16, 2024, which claims priority from U.S. Provisional Application No. 63 / 446,355 filed on Feb. 17, 2023. The foregoing applications are incorporated herein by reference in their entiretyFIELD OF THE INVENTION

[0002] The present disclosure relates generally to the field of conduit networks for fluid distribution. More particularly, the present invention relates to techniques for evacuating fluid conduits to clear the conduits of fluids contained therein.BACKGROUND

[0003] As known in the art, certain fluid conveyance systems are implemented with a backflow preventer device (hereinafter “BPD”). As used herein, “backflow” means the undesirable reversal of flow of a fluid into a conduit (e.g., pipe, hose, tubular, or other fluid conveyance or storage means). Conventional BPDs are designed to keep this from happening.

[0004] Conventional water distribution installations typically entail the use of a BPD as an integral component of the system. There are several kinds of BPD designs in conventional use. They range from simple to complex designs. Some BPDs are known as Reduced Pressure Zone assemblies. Simply put, a BPD is an elaborate one-way valve. It allows for fluid to flow in one direction into a system but will prevent any fluid from returning back into the fluid source or repository. BPDs are routinely used in various applications (e.g., commercial boilers, hospital and laboratory equipment, waste digesters, car washes, irrigation systems, etc.). A typical use for BPDs is in industrial and residential irrigation or sprinkler systems. These systems deliver water to plants and vegetation alike in a uniform and controlled manner.

[0005] A common drawback of BPDs is their susceptibility to failure under cold temperature conditions. Conventional BPDs are constructed with a combination of metallic and non-metallic components. When ambient temperature drops below freezing, certain components in the BPD typically break or fracture. This failure not only renders the BPD inoperable to perform its function, it also typically leads to uncontrolled leakage of the fluids conveyed by the respective conduits. Thus, a need remains for improved techniques to efficiently and effectively evacuate fluid conduits to prevent such BPD failures.SUMMARY

[0006] According to an aspect of the invention, a fluid conduit evacuation system includes a fluid conduit having a backflow prevention device linked thereon. A first valve is linked to the fluid conduit to control fluid flow into the conduit for passage through the backflow prevention device. An air supply device is linked to the conduit, between the first valve and the backflow prevention device, to inject air under pressure into the conduit to push any fluid within the backflow device therethrough.

[0007] According to another aspect of the invention, a method for evacuating a conduit includes closing a first valve linked to a fluid conduit to stop fluid flow through a backflow prevention device linked to the conduit; injecting air under pressure into the fluid conduit to push any fluid within the backflow device therethrough, wherein the injecting air under pressure is performed between the first valve and the backflow prevention device.

[0008] According to another aspect of the invention, an apparatus for evacuating a fluid conduit includes an air supply device configured to link into a fluid conduit. The air supply device is configured to inject air under pressure into the conduit to push out any fluid within a backflow prevention device linked to the conduit. The air supply device is configured to link to controls to control actuation of the device.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The following figures form part of the present specification and are included to further demonstrate certain aspects of the present disclosure and should not be used to limit or define the claimed subject matter. The claimed subject matter may be better understood by reference to one or more of these drawings in combination with the description of embodiments disclosed herein. Consequently, a more complete understanding of the present embodiments and further features and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numerals may identify like elements, wherein:

[0010] FIG. 1 shows a schematic of a fluid conduit evacuation system configuration according to an example of the present disclosure.

[0011] FIG. 2A shows a schematic of a fluid conduit evacuation system configuration in one mode of operation according to an example of the present disclosure.

[0012] FIG. 2B shows a schematic of the fluid conduit evacuation system configuration of FIG. 2A in another mode of operation according to an example of the present disclosure.

[0013] FIG. 2C shows a schematic of the fluid conduit evacuation system of FIG. 2A in a flushed mode of operation according to an example of the present disclosure.

[0014] FIG. 3 shows a schematic of a control unit according to an example of the present disclosure.

[0015] FIG. 4 shows a schematic of another control unit according to an example of the present disclosure.

[0016] FIG. 5 shows a schematic of another fluid conduit evacuation system configuration according to an example of the present disclosure.DETAILED DESCRIPTION

[0017] The foregoing description of the figures is provided for the convenience of the reader. It should be understood, however, that the embodiments are not limited to the precise arrangements and configurations shown in the figures. Also, the figures are not necessarily drawn to scale, and certain features may be shown exaggerated in scale or in generalized or schematic form, in the interest of clarity and conciseness.

[0018] While various embodiments are described herein, in the interest of clarity all features of an actual implementation may not be described in this specification. In the development of any such actual embodiment, numerous implementation-specific decisions may need to be made to achieve the design-specific goals, which may vary from one implementation to another. It will be appreciated that such a development effort, while possibly complex and time-consuming, would nevertheless be a routine undertaking for persons of ordinary skill in the art having the benefit of this disclosure. The following detailed description of exemplary embodiments, read in conjunction with the accompanying drawings, is merely illustrative and is not to be taken as limiting the scope of the invention.

[0019] FIG. 1 shows a fluid conduit evacuation system 100 embodiment of this disclosure. The schematic shows an irrigation or sprinkler system configured to distribute water to the surface grass and flora. A water conduit 10 network is formed of interconnected tubulars or pipes laid out in a desired manner to distribute the water to selected locations. As shown in FIG. 1, some of the conduits 10 are subterraneously disposed and some are above surface. Although conventional irrigation systems utilize PVC pipes and connections to form the conduit 10 system, embodiments of this disclosure are not limited to any particular type of conduit construction. It will also be appreciated that embodiments may be implemented for use with any fluid types (e.g., liquid, gas, suspended solids, or combinations of these).

[0020] FIG. 1 shows the system 100 incorporating a conventional BPD 12 coupled into the conduit 10 network. For irrigation systems, the BPD 12 is typically placed above surface as shown in FIG. 1. The system 100 has a main water inlet 14, as shown by the arrow. A first valve 16 is linked onto a first conduit 10A to control water flow from the inlet 14 into the first conduit. The first valve 16 provides a “master” valve between the water source (not shown) and the conduit system 100. Any conventional fluid valve may be used for the first valve 16 as known in the art (e.g., manually actuated, electrically actuated, or both). Suitable valves include HUNTER®valves offered by Hunter Industries. The first valve 16 may be disposed above surface or subterraneously, depending on the desired application. When the first valve 16 is in the open position, water from the inlet 14 is conveyed via the first conduit 10A for passage through the BPD 12. It will be appreciated that for applications in cold weather environments where the valves, conduits, inlet, or other components of the system 100 may be exposed to freezing temperatures, the articles can be appropriately insulated and / or disposed in weatherproof housings as known in the art to prevent freezing damage and maintain operation of the system.

[0021] A second conduit 10B is linked to the first conduit 10A between the first valve 16 and the BPD 12. An air supply device 18 is linked to the second conduit 10B to inject air under pressure into the first conduit 10A to push any fluid (water in the case of irrigation configurations) within the BPD 12 therethrough, as further explained below. As shown in FIG. 1, some embodiments may be implemented with a one-way valve 20 disposed between the air supply device 18 and the inlet 14. The one-way valve 20 protects the air supply device 18 from exposure to any water. Any conventional one-way fluid valve may be used for the valve 20 as known in the art. Other embodiments may also be implemented with an additional valve 22 disposed between the air supply device 18 and the one-way valve 20. Any conventional valve (e.g., mechanically actuated, electrically actuated, or both) may be used for valve 22. When installed, valve 22 provides an additional safety feature when in the closed position to prevent water from reaching the air supply device 18 in the event the one-way valve 20 fails.

[0022] On the other side of the BPD 12 (i.e., opposite the inlet 14 side), the first conduit 10A is linked with one or more additional conduits 10 to form a distribution network as desired. FIG. 1 shows a conduit system 100 implemented with a plurality of distribution conduits 10C, 10D, 10E to form a distribution network. For such embodiments, each conduit branch 10C, 10D, 10E can be implemented with its own respective “control” valve 24, 24′, 24″ to control water flow via the respective conduit stemming from the BPD 12. Any conventional valve (e.g., mechanically actuated, electrically actuated, or both) may be used for valves 24, 24′, 24″. In this manner, the various conduit distribution branches 10C, 10D, 10E can be regulated (via the respective valves 24, 24′, 24″) to provide water distribution via the sprinklers 25 coupled to each branch in a controlled manner as desired. For example, if water distribution is desired only for conduit branch 10C, then valve 24 is opened and valves 2424″ are closed. If water distribution is desired only for conduit 10E, then valve 24″ is opened and valves 24 and 24′ are closed. When all of the control valves 24, 24′, 24″ are in the closed position, no water is distributed through the system 100, even if the first valve 16 is in the open position to allow water entry via the inlet 14.

[0023] FIG. 1 shows an embodiment with a control unit 26 linked to the air supply device 18. The control unit 26 consists of a control unit configured with controls (e.g., electronics, processors, firmware, memory, dials, and / or switches) for a user to alter settings and parameters for actuation of the various valves 24, 24′, 24″ to control water distribution through the conduit system 100 as desired. Embodiments may be implemented with the control unit 26 configured with controls to electronically activate the valves 16, 22, 24, 24′, 24′ and the air supply device 18 as disclosed herein. As known in the art, control units 26 may be configured with internal controls 19 so the unit can be set or programmed to selectively activate water distribution by actuation of the respective valves at desired days / times, sequences, and for desired intervals. The control unit 26 can be coupled to a local electricity power feed and / or battery powered as known in the art. Embodiments may also be implemented with an internal back-up conventional or rechargeable battery kept charged via a trickle charge from the local electricity power feed.

[0024] The control unit 26 and / or the air supply device 18 can be disposed above surface and at a selected distance from the subterraneously disposed conduits of the system 100. In some embodiments, the control unit 26 and / or the air supply device 18 may be disposed indoors to protect the devices from the external environment. In some embodiments, the control unit 26 and / or the air supply device 18 may be disposed in close proximity to the inlet 14 and / or the BPD 12. Although not shown in the figures for clarity of illustration, it will be understood by those skilled in the art how wiring is distributed between the control unit 26, the air supply device 18, and the valves 16, 22, 24, 24′, 24″ in the system 100 for electrical operation.

[0025] As depicted in FIG. 1, some control unit 26 embodiments may be configured with conventional controls 19 and an antenna 28 to provide for wired or wireless control and operation of the system 100 or its individual components. Operation of the system 100 and / or its components may be monitored and controlled using a computing device 30. The computing device 30 may include, for example, a mobile phone, a tablet, a laptop computer, a desktop computer, an electronic notepad, a server computing device, etc. In some implementations, the system 100 can be implemented for remote control and monitoring via a cloud-computing architecture. With the computing device 30, the system 100 and its components can be remotely controlled to set automatic operation, to activate PBD 12 evacuation, and / or to adjust or limit the amount of fluid flow through the respective valves 16, 22, 24, 24′, 24″. It will be appreciated by those skilled in the art that the processors may be configured to perform as described herein using conventional software using any suitable computer language, electronics, communication network, and communication protocols. It will also be appreciated by those skilled in the art that embodiments for irrigation applications that include a conventional timer control unit 26 may be augmented by addition of electronics / software controls configured to actuate the valves 16, 22, 24, 24′, 24″ and / or the air supply device 18 for operation as disclosed herein. As disclosed herein, embodiments of the control unit 26 can encompass a single contained unit incorporating all of the controls and components, as well as a combination of multi-piece units comprising conventional timers and additional electronics / software controls, to perform the disclosed operations.

[0026] Operation of the system 100 for conduit evacuation will now be described. FIG. 2A shows the system 100 in operation when fluid distribution is desired via the conduit 10. In this mode, the first valve 16 is in the open position and fluid is flowing in from the inlet 14 into the first conduit segment 10A. The fluid flows through the BPD 12, past control valve 24 which is in the open position, and continues for distribution via the conduit network (see FIG. 1). The one-way valve 20 prevents any fluid from flowing to the air supply device 18. FIG. 2B shows the system 100 in operation when it is desired to evacuate the conduit 10 to clear the BPD 12 of fluid. In this mode, the first valve 16 is set in the closed position, stopping fluid flow from the inlet 14 into the first conduit segment 10A. The air supply device 18 is actuated to inject air under pressure into the first conduit 10A. Control valve 24 is opened to allow pressurized air to blow out any fluid within the BPD 12 and through the conduit behind the valve 24. FIG. 2C shows the system 100 after the air supply device 18 has blown out the fluid through the BPD 12 and cleared the first conduit segment 10A. At this stage, the air supply device 18 is deactivated and control valve 24 may be set to the closed position if desired. The evacuation process may be remotely, automatically, and / or autonomously controlled via a system 100 implemented with a control unit 26 configured to perform the operations as disclosed herein. In this manner, the BPD 12 and selected conduit segments can be cleared of fluid by operation of the air supply device 18 and the valves 24, 24′, 24″ (see FIG. 1). The entire conduit system 100 can be cleared of fluid if desired by sequentially activating the valves 16, 22, 24, 24′, 24″ and air supply device 18 to evacuate the respective conduit segments. The system 100 may be kept in this cleared mode indefinitely or until fluid distribution is again desired. When fluid distribution is desired, the first valve 16 is opened to allow intake flow via the inlet 14 and the control valves(s) 24, 24′, 24″ are opened in the desired pattern / sequence as described herein. It will be appreciated that system 100 embodiments are not limited to the number of valves and / or conduits that may be incorporated thereon. Embodiments may also be implemented with more than one air supply devices 18 linked to the system 100 to provide the required pressure to the conduits depending on how extensive the conduit network is laid out.

[0027] FIG. 3 shows an embodiment of an air supply device 18 according to this disclosure. An embodiment may be configured with a conventional compact air pump 32. Any suitable conventional electrically powered (AC or DC) air pump may be used. The air pump 32 pressure rating can vary depending on the total volume (i.e., the total internal volume of the conduits and the BPD) and viscosity of the fluid to be evacuated. For example, a pump 32 to evacuate a standard residential irrigation system may be implemented with a pump rated in the 50 psi range. The pump 32 may be powered via a local electricity power feed (e.g., the feed powering the control unit 26). Embodiments may also be configured with a conventional battery 34 to power the air supply device 18. Some embodiments may also be configured with a transformer / converter to provide a trickle charge to keep a rechargeable battery 34 charged via the local electricity power feed.

[0028] Embodiments of the air supply device 18 may be implemented for linking to a main control unit 26 and / or with their own independent controls module 36 including a processor, memory, and an antenna to provide for wireless remote control of the air supply device 18. In one mode of operation when evacuation of the BPD 12 is desired, the first valve 16 and control valve 24 are both set in the closed position (see FIG. 2). The air pump 32 is then actuated to pressurize and inject air into the conduit 10 between the air supply unit 18 and the control valve 24. When sufficient air pressure is reached, control valve 24 is opened and the air pressure flushes out the fluid through the BPD 12 and out through the conduit behind the control valve 24 (see FIG. 2C). The control unit 26 or controls module 36 may be programmed to actuate the air pump 32 for a set period of time (depending on the pump pressurization rating) before control valve 24 is opened. Some embodiments may be implemented with a smart control valve 24 configured to switch from closed to open when a specific pressure head is achieved. Embodiments may also be implemented with a conventional air pump 32 equipped with a shutoff sensor that automatically deactivates the pump when a selected pressure is achieved.

[0029] FIG. 4 shows another embodiment of the air supply device 18 according to this disclosure. An embodiment may be configured similar to the embodiment of FIG. 3, including a compact vessel 38 to hold air under pressure. The vessel 38 may be any suitable conventional container designed to hold compressed air. The vessel 38 may be pressurized by the air pump 32, or alternatively with a hand pump or CO2 cartridge (via conventional hose / fitting 40) if there is no electrical power to actuate the air pump 32. With this configuration, conduit and BPD 12 evacuation can be rapidly achieved. In one mode of operation when evacuation of the BPD 12 is desired, the first valve 16 is set in the closed position and control valve 24 is set in the open position (see FIG. 2B). The vessel 38 is then actuated to allow injection of the pressurized air into conduit 10 to flush out the fluid through the BPD 12 and out through the conduit behind control valve 24. The air pump 32 re-pressurizes the vessel 38.

[0030] Returning to FIG. 1, embodiments may also be implemented with a conventional temperature sensor 27 to measure the ambient temperature. Although FIG. 1 shows the temperature sensor 27 disposed on the control unit 26, it will be appreciated that the sensor can be located anywhere to measure the ambient temperature and linked (wired or wirelessly) to the control unit 26 and / or controls module 36 such that the unit processor is triggered to actuate the system 100 and evacuate the BPD 12 as described herein when a specific temperature is detected by the sensor. For irrigation systems 100 implemented with BPDs 12 susceptible to failure when the ambient temperature falls below the freezing point and freezes the water in the BPD, the control unit 26 and / or controls module 36 can be programmed to activate the evacuation process when triggered by the temperature sensor 27 at a set temperature before freezing occurs.

[0031] FIG. 5 shows another fluid conduit evacuation system 100 embodiment of this disclosure. In this configuration, the control unit 26 consists of a simplified device containing a battery 34, an air supply device 18, and a conventional electronics (switches, etc.). As described above with respect to other system 100 embodiments, this control unit 26 can be coupled to a local electricity power feed and / or battery powered as known in the art. Embodiments may also be implemented with an internal back-up conventional or rechargeable battery kept charged via a trickle charge from the local electricity power feed.

[0032] The system 100 has a main fluid inlet 14, as shown by the arrow. A first “master” valve 16 is coupled the first conduit 10A to control fluid flow from the inlet 14 into the conduit. A one-way valve 20 is disposed between the control unit 26 and the inlet 14 to prevent fluid ingress to the control unit. In this embodiment an additional conduit 10B is coupled to the first conduit 10A downflow from the BPD 12 linked therein. The additional conduit is configured with a control valve 24 and terminates with a sprinkler 25 head.

[0033] As shown in the FIG. 5 embodiment, the control unit 26 is electrically linked to the master valve 16 and the control valve 24 via conventional wiring 42. When it is desired (or automatically triggered) to evacuate the system 100 of fluid, the control unit 26 sends an electrical signal, via wire 42, to close the master valve 16 and open the control valve 24. The control unit 26 then activates the internal air supply device 18 and the conduits 10A, 10B are flushed out via the sprinkler 25 head as described herein. Any fluid in the intermediate BPD 12 is also flushed through and out via the sprinkler 25 head. In this embodiment, control valve 24 acts as a “flush” valve for the system 100. An advantage of the system 100 of FIG. 5 is that the simplified control unit 26 does not need to be configured with extra internal controls to selectively activate fluid distribution by actuation of multi-conduit valves at timed sequences, or intervals. The simplified system 100 provides greater operational reliability and the control unit 26 can be installed and wired into existing distribution systems without requiring removal or overhaul of the existing system components. It will be appreciated that for systems 100 configured for fluids incorporating gases, the sprinkler 25 head can be replaced with a conventional vent head / valve as known in the art. It will also be appreciated that some system 100 embodiments may be implemented with the additional conduit 10B implemented via a simple venting conduit (e.g., a hose) linked to the first conduit 10A downflow of the BPD 12.

[0034] It will be appreciated that system 100 embodiments of this disclosure may be configured for fully automatic and autonomous operation to evacuate the conduits and BPDs. As described herein, the control unit 26, controls module 36, and / or the air supply device 18 can be programmed for autonomous activation at preselected days, times, intervals, and / or when a specific ambient temperature is detected. Those skilled in the art will also appreciate that the control unit 26, controls module 36, and / or the air supply device 18 can also be programmed to activate evacuation upon any number of input signals (e.g., when a fire alarm is triggered where the system 100 conveys explosive fluids). Use of conventional valves that can be actuated via various combined means (e.g., manually, electrically, wireless remotely) adds greater versatility to the system 100. For example, as described herein system 100 embodiments may be operated completely remotely via the computing device 30 (see FIG. 1), allowing a user to remotely configure fluid distribution via the conduit network and activate evacuation of the conduits / BPD 12 at will. If the external electrical power feed to the control unit 26 or the controls module 36 is lost, the BPD 12 may still be evacuated by manually activating battery-powered controls (e.g., via switches, dials) on the controls module 36 to actuate the valves 16, 24, 24′, 24″ and air supply device 18 as described herein. In the event total electrical power is lost, the systems 100 may still be activated to evacuate the BPD 12 by manually setting the valves 16, 24, 24′, 24″ as described herein and manually activating the compressed air vessel 38 (via a manual valve on the vessel) to flush the system.

[0035] In light of the principles and example embodiments described and illustrated herein, it will be recognized that the example embodiments can be modified in arrangement and detail without departing from such principles. It will be appreciated by those skilled in the art that the disclosed embodiments are not limited to use with any one particular type of fluid. What is claimed as the invention, therefore, are all implementations that come within the scope of the following claims, and all equivalents to such implementations.

Claims

1. A fluid conduit evacuation system, comprising:a fluid conduit having a backflow prevention device linked thereon;a first valve linked to the fluid conduit to control fluid flow into the conduit for passage through the backflow prevention device; andan air supply device linked to the conduit between the first valve and the backflow prevention device,wherein the air supply device is configured to inject air under pressure into the conduit to push any fluid within the backflow device therethrough.

2. The system of claim 1 further comprising controls to electrically control actuation of the first valve and / or the air supply device.

3. The system of claim 1 wherein the first valve and / or the air supply device are configured for remote control.

4. The system of claim 1 wherein the conduit extends out from the backflow prevention device and comprises at least one sprinkler linked thereon.

5. The system of claim 1 further comprising a plurality of conduits linked to a conduit extending out from the backflow prevention device.

6. The system of claim 1 further comprising a second valve to control fluid flow between the air supply device and the conduit.

7. A method for evacuating a conduit, comprising:closing a first valve linked to a fluid conduit to stop fluid flow through a backflow prevention device linked to the conduit; andinjecting air under pressure into the fluid conduit to push any fluid within the backflow device therethrough,wherein the injecting air under pressure is performed between the first valve and the backflow prevention device.

8. The method of claim 7 wherein the closing the first valve and / or injecting air under pressure is electronically actuated.

9. The method of claim 7 wherein the closing the first valve and / or injecting air under pressure is based on an ambient temperature reading.

10. The method of claim 7 further comprising remotely controlling the first valve and / or the injecting air under pressurize.

11. The method of claim 7 wherein the conduit extends out from the backflow prevention device and comprises at least one sprinkler linked thereon.

12. The method of claim 7 wherein a plurality of conduits are linked to a conduit extending out from the backflow prevention device.

13. The method of claim 12 wherein a plurality of sprinklers are linked to the plurality of conduits.

14. The method of claim 7 further comprising actuating a second valve to control fluid flow between an air supply device and the fluid conduit.

15. An apparatus for evacuating a fluid conduit, comprising:an air supply device configured to link into a fluid conduit;wherein the air supply device is configured to inject air under pressure into the conduit to push out any fluid within a backflow prevention device linked to the conduit; andwherein the air supply device is configured to link to controls to control actuation of the device.

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