Fluid port with dielectrics

Abstract

A mating flange may be rigidly coupled to a fluid port. The mating flange may be coated with an electrically-resistive coating. The mating flange may include mounting points for fasteners for coupling to a spool flange of a pipe spool. The mating flange may be configured to accommodate a dielectric gasket to between the spool flange and mating flange during coupling.

Description

FLUID PORT WITH DIELECTRICS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 640,696, filed April 30, 2024, titled Insulating Coating for Fluid Port, which is hereby incorporated by reference in its entirety.FIELD

[0002] The following disclosure relates to fluid ports with dielectric insulation and / or components.BACKGROUND

[0003] Electrolyzer systems use electrical energy to drive a chemical reaction. For example, water is split to form hydrogen and oxygen. The products may be used as chemical feedstocks and / or energy sources. In recent years, improvements in operational efficiency have made electrolyzer systems competitive market solutions for energy storage, generation, and / or transport. For example, the cost of generation may be below $10 per kilogram of hydrogen in some cases. The water and / or other fluids may be cycled through the electrochemical stack and various portions of the plant. Decreases in cost, increases in efficiency, operational longevity, and / or improvements in operation will continue to drive installation of electrolyzer systems.BRIEF DESCRIPTION OF THE DRAWINGS

[0004] Example implementations are described herein with reference to the following drawings.

[0005] Figure 1A shows an example fluid port assembly.

[0006] Figure IB shows an alternate view of the example fluid port assembly of Figure1A.

[0007] Figure 2 shows an example method of power dissipation within an electrochemical stack.

[0008] Figure 3 shows an illustrative example fluid port assembly.

[0009] Figure 4 shows an alternate blow-up view of the flanges of the illustrative example fluid port assembly of Figure 3.

[0010] Figure 5 shows an illustrative example method of assembly for the illustrative example fluid port assembly of Figure 3.DETAILED DESCRIPTION

[0011] The discussed architectures and techniques may be used with fluid ports where the fluid traverses an electrical potential difference along the path of the fluid through fluid port. In various implementations, components of a fluid port assembly (e.g., a mating flange and / or a pipe spool) may be coated. For example, the mating flange may be coated on one or more internal or external surfaces with a resistive coating. Similarly, the pipe spool may be lined / coated on various internal and / or external surfaces.

[0012] In various contexts, such as various electrochemical applications, fluid may move between a point at operating potential of a device within a plant and a ground point either within the device or at some other location within the plant. To avoid leakage (or other escape) of the fluid, the various portions of the piping (or other means of conveyance) may be tightly physically coupled to one another. In some cases, the fluid may be held at a high fluid pressure (e.g., up to 10 bar or more) and / or temperature. Thus, to maintain pressure without undue risk of physical compromise, metal and / or other rigid and / or heat-resistive material may be used.

[0013] Conductive, rigid materials, such as metals, may provide the physical properties to support the pressure, leakage, and heat-resistance requirements of such electrochemical applications. In some cases, the conductivity of metal may be desirable to ensure that the various potions of the fluid path at held at known potential. Specifically, conductive metal components held in direct contact with other metal components provide assurance that the coupled parts are both at the same potential. This may facilitate holding known portions of the electrochemical plant piping at ground, while only intentionally isolated portions of the plant piping are allowed to float relative to ground.

[0014] Thus, at various specifically selected locations plant piping may have direct physical coupling where one side of the "tie point" is held at ground (or another reference voltage) and the other side is allowed to float relative to ground, e.g., float in accord with the operating potential point of the electrochemical stack.

[0015] According to the conventional wisdom, dielectric separators (e.g., gaskets, stud sleeves, and washers) should be used to isolate one metal flange (e.g., a metal mating flange) from another metal flange (e.g., a pipe spool flange). Accordingly, the dielectric separators allow for the use of the metal faces of the flanges to face one another and generate a robust seal with the dielectric gasket at a wide range of fastener torque levels. Similarly, according to the conventional wisdom the dielectric sleeves and washers allow for the fasteners (holding the two flanges in place) to be readily tightened to a level within a wide range of fastener torques because the robust metal outer surface of the metal flanges remains undisturbed by the fastener.

[0016] According to the conventional wisdom, comparatively soft materials with comparatively fragile surfaces that may be disturbed / destroyed by compressive force from fasteners should be avoided because such materials will reduce the tolerance range for the application of torque to the fasteners. Thus, according to the conventional wisdom, tie points using flanges with comparatively soft materials are undesirable because such flanges are more prone to failure and leakage.

[0017] Contrary to the conventional wisdom, various implementations herein use coated mating flanges for fluid ports and / or lined pipe spools for coupling to the mating flange. As recognized herein and unrecognized by the conventional wisdom, the coated mating flanges provide an unexpected reduction in system downtime for cleaning because the coatings reducing electrical creep associated with longer term high voltage system operation. Moreover, the surface linings of the pipe spool (and the spool's corresponding spool flange) provide an unexpected decrease in pipe spool replacements. Thus, the spool linings unexpectedly reduce the frequency at which there is a need of torquing / detorquing of fasteners. Thus, the disadvantages cited by the conventional wisdom are mitigated by the unexpected advantages of the pipe spool linings.

[0018] In various implementations, internal surface linings may be used for the pipe spool to decrease electrical contact with fluids flowing through the pipe spool. In various implementations, external surface linings may be avoided for the pipe spool to reduce the chance that the pipe spool is incidentally allowed to float relative to a ground potential. Nevertheless, such external linings / coatings may provide additional protection fromunwanted electrical current transfer between the pipe spool and, for example, the mating flange.

[0019] Figure 1A shows an example fluid port assembly (FPA) 100. The example FPA 100 includes a mating flange 110 for coupling with a pipe spool 130. The FPA 100 may further include fasteners 102 and dielectric separators: dielectric washers 104, dielectric fastener sleeves 106 (e.g., stud sleeves) and a dielectric gasket 108. In an illustrative example implementation, the mating flange 110 may provide a rigid coupling point to a fluid port of an electrochemical system for plant piping, e.g., via coupling to the pipe spool 130.

[0020] The pipe spool may include a lining 132, which in the example, includes an internal lining. The lining 132 may isolate the pipe spool 130 from fluid flowing through the pipe spool 130. The lining 132 may be made from electrically-insulating materials. In some cases, the lining 132 may include an anti-corrosive material. As examples, a polytetrafluoroethylene (PTFE, e.g., Teflon®) lining, a plastic lining (such as high-density polyethylene (HDPA), perfluoroalkoxy polymer (PFA), and / or other plastic), and / or other polymer lining may be used. The pipe spool may have a spool flange 134 on one end for mating with the mating flange 110. The flange face of the spool flange 134 may include ridges, seating grooves, and / or other features to host the dielectric gasket 108.

[0021] The mating flange 110 may be surrounded by an electrica lly-resistive coating 112. The coating 112 may include an epoxy coating, a powder coating, an oxide coating, and / or other resistive coating. In an example implementation, a fusion-bonded epoxy (FBE) may serve as the coating 112.

[0022] The mating flange may have a metal core portion, e.g. below the coating 112. The metal core portion may provide rigidity and robustness to support the high-pressure / high temperature operating conditions (e.g., associated with electrochemical stack operation).

[0023] S imilarly to the spool flange 134, the flange face of the mating flange 110 may include ridges, seating grooves, and / or other features to host the dielectric gasket 108. When the spool flange and the mating flange are coupled to one another, the dielectric gasket 108 may extend beyond the outer radius of the flange faces, as shown. However, although not shown, in some implementations, the dielectric gasket 108 may be flush withthe outer radius of one or more of the flange faces and / or the radius of the dielectric gasket 108 may be shorter than one or more of the radii of the flange faces.

[0024] The mating flange 110 may further include mounting points 114 for fasteners 102 that couple the mating flange 110 to the spool flange 134. The spool flange 134 may include corresponding mounting points 136 for the fasteners.

[0025] The fasteners 102 may be isolated from the mating flange, at least in part, by the dielectric washers 104 and fastener sleeves 106. As shown for bolt-type fasteners Figure 1A, the sleeves 106 surround the fasteners 102 while secured at the mounting points 114, 136. The washers 104 hold the bolt heads / nuts off the surface of the mating flange 110. The coating 112 of the mating flange 110 provides additional electrical isolation for the mating flange 110.

[0026] Although the coating 112 of the mating flange 110 provides isolation from the fasteners 102 for the mating flange at all times, the comparatively large area coverage (e.g., in reference to the washers 104 and / or sleeves 106) of the coating 112 provides mitigation of electrical creep and arcing. When the system is clean and free of surface particles and the ambient gas medium is similarly free of particulate matter, the physical separation provided by the washers 104 may be selected to be sufficient to guard against unwanted current transfer between the fasteners 102 (e.g., which may be held at ground) and the mating flange 110 (e.g., which may be at the operating voltage of the system, such as an electrochemical stack). However, particles on the surface and in the ambient atmosphere may reduce the effective physical separation between the fasteners 102 and the mating flange 110. The accumulation / presence of these particles may occur in random patterns. Accordingly, the precise path (and length of that path) where particles form a "bridge" between fasteners 102 and the mating flange 110 may be unpredictable (or practically so). Thus, the radius needed for the washer to effectively mitigate such transient current flows may be quite large and may be impractical from a physical standpoint. Moreover, the potential at which the system operates may attract particles. Accordingly, the act of operation may accelerate particle accumulation. Thus, conventional systems rely on downtime for cleaning and particle removal.

[0027] Various implementations herein use a coating 112 to provide mitigation for such transient current flows. The coverage provided by the coating effects protection from such transient current flows even with the precise current path and length thereof is unknown.

[0028] Referring again to the pipe spool 130, the lining 132 may provide mitigation of galvanic corrosion. Fluid may flow through the mating flange (e.g., at the operation potential) and through the pipe spool (e.g., at ground). The difference in potential may cause the fluid to form charged ions. Thus, an electrical current may be transferred as a result of the fluid flow. Galvanic corrosion may increase as this current increases. The resultant current is proportional to the cross-sectional area of the pipe, the speed of the flow, and the separation length by which the ions must flow from cathode to anode. Because the surface area of the pipe scales with its cross-sectional area, reducing the cross- sectional area may result in more concentrated corrosion. Thus, the reduced corrosion may occur over a smaller area. Thus, reducing the cross-sectional area has limited benefit because the intensity of corrosion may, in some cases, remain the same or similar (or even increase). In conventional systems, the separation distance (between anode / cathode) could be controlled by the dielectric gasket 108. However, to maintain seal strength, fastener integrity, and physical robustness, there are practical limitations to how thick the dielectric gasket 108 can be. From a practical standpoint, a very thick dielectric gasket effectively becomes a short dielectric pipe. Because of the operating pressure / temperature, there may be practical limitations to the length of dielectric piping that may be used (as discussed above). Similarly, flow can be controlled by using parallel fluid ports. However, such increases in ports may be associated with increases in system cost and complexity.

[0029] As recognized herein, the effective separation distance may be increased by chemically / electrically isolating the pipe spool from the fluid flowing through the pipe spool. Accordingly (and contrary to the conventional wisdom) various implementations implement a lining within the pipe spool. Various polycarbonate linings may be used. Linings that provide chemical and / or electrical isolation, e.g., via a thin layer, may be used. Further, thermally robust linings may be desirable. For example, PTFE linings may be used.

[0030] The use of coatings / linings may decrease the range of fastener torque levels that may be used when mounting the spool flange to the mating flange. For example, thecoati ngs / l i ni ngs may be harmed via over tightening of fasteners. In some cases, the coatings / linings may interfere with seal creation. Nevertheless, reduction in downtime and decrease in component degradation reduces the need for removal of the pipe spool from the mating flange.

[0031] Further, various implementations herein add additional "tie" points, e.g., points where two components mating and may be disengaged from one another, proximate to the meeting point of the pipe spool 130 and mating flange 110. The addition tie points further reduce the frequency with which the pipe spool 130 and mating flange 110 may need to be disengaged with one another. Thus, the flexibility and reconfigurability of conventional systems may be maintained even when the coatings / linings are employed. For example, an additional tie point may be placed on the "far" end of the pipe spool 130 opposite the spool flange 134. Thus, the operational portion of the system (e.g., the electrochemical stack) may be disengaged from the broader plant piping via the far end of the pipe spool 130 rather than via disassembly of the FPA 100. Thus, the FPA 100 may be treated as a permanent and / or semi-permanent joint, while the tie point proximate to the FPA 100 is used for maintenance disassembly, reconfiguration, and / or other disengagement of the operating system from the broader plant piping.

[0032] Figure IB shows an alternative view of the FPA 100. In the alternative view, the fasteners 102 are shown retracted from the mating flange 110 to further show the assembly process for the FPA 100.

[0033] Referring now to Figure 2, a flow diagram of an example method of power dissipation in an electrochemical stack is shown. In the example method 200, power may be dissipated, e.g., thermally and / or electrically, by allowing fluid to flow through (and out of) the electrochemical stack. The fluid may carry changed ions to effect an electrical dissipation of power. The fluid may also heat via thermal contact with the system and carry the captured heat out of the system via convection.

[0034] At block 202, fluid may be pushed through the fluid port of the electrochemical stack. For example, the FPA 100 may be disposed on the fluid port. Thus, pushing the fluid through fluid port may direct the fluid flow through the mating flange 110 and pipe spool 130, at block 204.

[0035] While the fluid flow is directed through the FPA 100, the pipe spool 130 may be held at ground and the mating flange 110 may be in electrical contact with the electrical chemical stack, at block 206. Consequently, the mating flange may be floating electrically at the operating potential of the electrochemical stack.

[0036] Referring now to Figure 3, Figure 3 shows an illustrative example FPA 300. In the illustrative example FPA 300 at PTFE-lined elbow pipe spool 330 is coupled to a FBE coated mating flange 310. A grooved pup 313 is connected to the mating flange 310. A pipe plug 311 may be disposed on the grooved pup 313 to accommodate fluid flow through the grooved pup 313 to operate as an over-pressure emergency release for the FPA 300. The grooved pup 313 may be used for fluid coupling to the broader plant (e.g., at a ground or reference potential). The pipe spool may be coupled to a fluid port at the operation potential of the operating system. The mating flange 310 is coupled to the pipe spool 330 via the spool flange 334.

[0037] The spool flange 334 and mating flange 310 include mounting points 314, 336 to accommodate studs 302 with dielectric sleeves 306. The studs 302 fasten to the flanges 334, 310 via hex nuts 309. Washers 304, 305, 307 may space the flanges 334, 310 away from the hex nuts 309. The washers 304 may be dielectric, dielectric coated, and / or galvanized for conductivity / corrosion protection. Similarly, the studs 302 and hex nuts 309 may be dielectric, dielectric coated, and / or galvanized for conductivity / corrosion protection. The washers 304 may include flat washers 304, 307 which may be dielectric 304 and / or metal 307 and Belleville (or other spring-tension washers) 305.

[0038] The spool flange 334 and mating flange 310 are separated by a mating gasket 308.

[0039] Figure 4 shows an example blow-up view 400 of the coupled spool flange 334 and mating flange 310 of the illustrative example FPA 300.

[0040] Figure 5 shows an example assembly method for the example FPA 300. The studs 302 are inserted into the mounting points 314, 336 with the sleeves 306 and washers 304, 305, 307 while the gasket 308 is inserted between the spool flange 334 and mating flange 310 (502). The hex nuts 309 are hand tightened (504). The hex nuts 309 are tightened to about 55%-75% of a selected final torque using a torque wrench (506) in a distributedtightening pattern (e.g., such as a star pattern with points selected based on the number of mounting points). After all hex nuts 309 are tightened to about 55%-75% of the selected final torque, the hex nuts are tightened to the selected final torque using a torque wrench in the distributed tightening pattern (508). Optionally, the nut tightening may be subdivided into additional tightening stages to reach the selected final torque. The selected final torque may be determined based on the characteristics of the FBE coating of the mating flange 310 and / or the PTFE lining of the pipe spool 330 with regard to maintaining structural integrity of the coatings / linings while maintaining a fluid seal under operating temperatures and pressures. In some implementations, the selected final torque further be based on characteristics of the dielectric gasket and / or dielectric washers. The Belleville and / or other spring-tension washers may be selected to have spring characteristics consistent with tightening at the final selected torque. As an illustrative example, the final selected torque in an illustrative example scenario may be about 74 foot-pounds and the first tightening stage may include tightening to 51 foot-pounds. However, other final torques in other implementations and scenarios may be selected based on the considerations discussed above.

[0041] One or more implementations of the disclosure may be referred to herein, individually and / or collectively, by the term "invention" merely for convenience and without intending to voluntarily limit the scope of this application to any particular invention or inventive concept. Moreover, although specific implementations have been illustrated and described herein, it should be appreciated that any subsequent arrangement designed to achieve the same or similar purpose may be substituted for the specific implementations shown. This disclosure is intended to cover any and all subsequent adaptations or variations of various implementations. Combinations of the above implementations, and other implementations not specifically described herein, are apparent to those of skill in the art upon reviewing the description.

[0042] As used herein, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0043] As used herein, "for example / ' "for instance," "such as," or "including" are meant to introduce examples that further clarify more general subject matter. Unless otherwise expressly indicated, such examples are provided only as an aid for understanding implementations illustrated in the present disclosure and are not meant to be limiting in any fashion. Nor do these phrases indicate any kind of preference for the disclosed implementations.

[0044] Table 1 includes various examples.

[0045] The Abstract of the Disclosure is provided to comply with 37 C.F.R. §1.72(b) and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, various features may be grouped together or described in a single implementation for the purpose of streamlining the disclosure. This disclosure is not to be interpreted as reflecting an intention that the claimed implementations require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter may be directed to less than all of the features of any of the disclosed implementations. Thus, the followingclaims are incorporated into the Detailed Description, with each claim standing on its own as defining separately claimed subject matter.

[0046] It is intended that the foregoing detailed description be regarded as illustrative rather than limiting and that it is understood that the following claims including all equivalents are within the scope of the disclosure. The claims should not be read as limited to the described order or elements unless stated to that effect. Therefore, all implementations that come within the scope and spirit of the following claims and equivalents thereto are included within the disclosure.

Claims

CLAIMS1. A fluid port assembly including: an internally-insulator-lined pipe spool; a resistive-coated mating flange electrically insulated from and rigidly coupled to the internally-insulator-lined pipe spool; and a dielectric gasket disposed between the pipe spool and the mating flange.

2. The fluid port assembly of claim 1, where the internally-insulator-lined pipe spool includes a polytetrafluoroethylene lining.

3. The fluid port assembly of claim 1, where the resistive-coated mating flange includes a fusion-bonded epoxy coating.

4. The fluid port assembly of claim 1, where an internal lining of the internally- insulator-lined pipe spool extends a separation distance between an operating potential point at an interface with the mating flange and a ground point at an opposite end of the internally-insulator-lined pipe spool.

5. The fluid port assembly of claim 4, where extension of the separation distance reduces a speed of galvanic corrosion.

6. The fluid port assembly of claim 1, where a joint between the internally- insulator-lined pipe spool and the resistive-coated mating flange includes a permanent joint to avoid undoing a torque application to bolts joining the internally-insulator-lined pipe spool and the resistive-coated mating flange.

7. The fluid port assembly of claim 1, where the resistive-coated mating flange reduces a likelihood of transient current flow from one or more fasteners to the resistive- coated mating flange, the fasteners fastening the resistive-coated mating flange to the internally-insulator-lined pipe spool.

8. The fluid port assembly of claim 1, where the resistive-coated mating flange provides a rigid coupling point for an electrochemical stack.

9. The fluid port assembly of claim 8, where the resistive-coated mating flange couples electrochemical stack operating potential point to the internally-insulator-lined pipe spool, the internally-insulator-lined pipe spool electrically coupled to electrochemical plant piping held at a ground point.

10. The fluid port assembly of claim 8, where the fluid port assembly provides electrical energy dissipation to the electrochemical stack via fluid transfer through the fluid port assembly.

11. The fluid port assembly of claim 1, where the dielectric gasket extends beyond an outer radius of the resistive-coated mating flange and / or a spool flange of the internally- insulator-lined pipe spool.

12. The fluid port assembly of claim 1, where the dielectric gasket ends flush with an outer radius of the resistive-coated mating flange and / or a spool flange of the internally- insulator-lined pipe spool.

13. The fluid port assembly of claim 1, where an outer radius of the resistive-coated mating flange and / or a spool flange of the internally-insulator-lined pipe spool extends beyond the dielectric gasket.

14. The fluid port assembly of claim 1, further including one or more dielectric washers to electrically isolate one or more bolts from the mating flange, the one or more bolts fastening the mating flange to the pipe spool.

15. The fluid port assembly of claim 1, further including one or more dielectric sleeves to electrically isolate one or more bolts from the resistive-coated mating flange, the one or more bolts fastening the resistive-coated mating flange to the internally- insulator-lined pipe spool.

16. A mating flange including: an electrical ly-resistive coating; mounting points configured to, at least in part, rigidly mated to the mating flange to a pipe spool; and a flange face configured to accept a dielectric gasket disposed between pipe spool and the mating flange when mated.

17. The mating flange of claim 16, where the e lectrica I ly-resistive coating includes a fusion-bonded epoxy coating.

18. The mating flange of claim 16, where the mating flange provides a rigid coupling point for a fluid port of an electrochemical stack.

19. The mating flange of claim 16, further including one or more dielectric washers to electrically isolate one or more bolts from the mating flange, the one or more bolts fastening the mating flange to the pipe spool.

20. The mating flange of claim 16, further including one or more dielectric sleeves to electrically isolate one or more bolts from the mating flange, the one or more bolts fastening the mating flange to the pipe spool.

21. A pipe spool including: an electrically-insulative internal pipe lining; mounting configured to, at least in part, rigidly mate the pipe spool to a mating flange; anda spool flange configured to accept a dielectric gasket disposed between the pipe spool and the mating flange when mated.

22. The pipe spool of claim 21, where the electrically-insulative internal lining of the pipe spool includes a polytetrafluoroethylene lining.

23. The pipe spool of claim 21, where the electrically-insulative internal lining of the pipe spool extends a separation distance between an operating potential point at an interface with the mating flange and a ground point at an opposite end of the pipe spool.

24. The pipe spool of claim 23, where extension of the separation distance reduces a speed of galvanic corrosion.

25. The pipe spool of claim 21, where the pipe spool provides electrical energy dissipation to an electrochemical stack via fluid transfer through the pipe spool.

26. A method of power dissipation within an electrochemical stack, the method including: causing a flow of fluid through a fluid port of the electrochemical stack, the fluid including charged ions; directing, via coupling between a mating flange and a spool flange of a pipe spool, the fluid flow through the pipe spool, the pipe spool internally insulator lined, the mating flange including an electrically-resistive coating; and holding the pipe spool at ground while allowing a mating gasket to electrically couple to the electrochemical stack at an operating potential of the electrochemical stack.

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