Submersible low-temperature liquid hydrogen pump assembly

Abstract

A cryopump assembly, including a centrifugal pump and an induction motor, specially configured for delivery of liquid hydrogen (LH2) from a cryogenic LH2 tank to various application scenarios, has a horizontal configuration and includes an offset discharge port to prevent the occurrence of gas blockage phenomena. A one-piece vacuum jacket housing may be employed to enclose various portions of the centrifugal pump and the induction motor to prevent heat loss, while another embodiment is to lubricate the bearings and cool the induction motor with LH2 flow through the induction motor. The centrifugal pump can be of a single-stage type or a multi-stage type, and each stage unit comprises an impeller and a guide vane connected with a guide vane shell. The pump shares one motor / pump shaft with the motor. Another embodiment is that the cryopump assembly is vertically submerged in a cryogenic LH2 tank, or vertically submerged in a sump vessel secured to the exterior or interior of the cryogenic LH2 tank.

Description

[0001] Cross-references to related applications

[0002] This utility model patent application claims priority to U.S. Provisional Patent Application No. 63 / 533,735, filed August 21, 2023, authored by inventor Craig James Fennessy, entitled “Hydrogen Submerged Electric Pump”; the entire application of which is incorporated herein by reference. Background Technology

[0003] This invention relates to a cryogenic pump assembly specifically designed for liquid hydrogen (LH2), and more generally to a cryogenic liquid hydrogen pump assembly, which, with easy modification or simplification, can also be applied to liquid nitrogen (LN2), liquefied natural gas (LNG), and other cryogenic pumping systems. If the cryogenic pump assembly is used for LNG, the specially designed cryogenic pumping assembly can also be configured to be submerged in an LNG storage tank. Similarly, the cryogenic pump assembly specifically designed for LH2 can also be configured to be vertically submerged in a cryogenic LH2 storage tank. The invention also discloses a cryogenic LH2 pump assembly configured without a vacuum jacket, eliminating the need for submersion in a cryogenic LH2 storage tank, and instead utilizing the process fluid flowing through the pump assembly to lubricate the bearings and cool the induction motor.

[0004] When pumping cryogenic liquids, two common pump types are centrifugal pumps and reciprocating pumps. Centrifugal pumps rely on a rotating disc to move the process liquid and circulate it through the system. Increasing the impeller diameter or rotational speed can increase the head or flow rate. Centrifugal pumps are used in high-flow, low-head applications. Therefore, centrifugal pumps are preferred in most LH2 applications. Reciprocating pumps employ a crankshaft and connecting rod mechanism similar to an internal combustion engine and are used in high-pressure applications, but their flow rate is much lower. Centrifugal pumps are also much less efficient than reciprocating pumps; the overall efficiency of centrifugal pumps is typically 30%-60%, while the overall efficiency of reciprocating pumps can generally reach 85% over their entire operating range. It is worth noting that many reciprocating pumps require a booster pump, which is a centrifugal pump, to help prevent cavitation.

[0005] Centrifugal pumps are classified into various designs, employing different sealing technologies to isolate process fluids from the atmosphere. Cryogenic centrifugal pumps used in the industrial gas sector are typically used to transfer liquids from one storage tank to another. These pumps can be stationary or vehicle-mounted and can be applied to continuous or intermittent process flows. Sealing cryogenic centrifugal pumps is not only challenging but also a maintenance issue. Cryogenic mechanical seals have become standard in the industrial market due to their availability, simple design, and cost advantages. These mechanical seals are relatively expensive and require ongoing maintenance. Mechanical seals are highly sensitive to the pump's startup method. Improper cooling and startup procedures can significantly shorten the seal's lifespan.

[0006] When a mechanical seal leaks, process fluid is released into the atmosphere. In the industrial gas industry, since the gases are usually relatively safe, such as nitrogen, argon, and oxygen, a small amount of process fluid vaporizing and leaking into the atmosphere is generally not considered a problem.

[0007] Because no container is needed between the stationary and rotating components, submersible electric motor pumps can solve many of the aforementioned mechanical seal leakage problems. As the name suggests, the electric motor is immersed in the process liquid. The motor rotor is coupled to the pump shaft, and the motor stator is also immersed in the process liquid. This design was popularized by JC Carter Pump Company many years ago (see U.S. Patent No. 3,369,715, "Submersible Pumping System," issued to James C. Carter on February 20, 1968). This patent generally discloses an LNG pumping and storage system, including a pump and electric motor immersed in the bottom of an LNG-containing tank, which can discharge LNG from the bottom to the top of the tank; this system is currently the most widely used. In other words, submersible electric motor pumps are widely used in propane, ethane, and LNG applications. Industrial gases are inert liquids and therefore inherently safe, but other applications such as propane, ethane, and LNG may not be as safe. Therefore, the reason why flammable liquids are acceptable is that when both the motor and pump are submerged in the liquid, there is no oxygen to support any kind of combustion or fire. It is important to note that these applications are all cryogenic.

[0008] Due to the extremely low temperatures, cryogenic pumps have unique design considerations, typically requiring minor design modifications for each application scenario and type of process fluid. Currently, significant research and development is underway on LH2, aiming to utilize it as a green energy source. More specifically, sustainable green energy refers to LH2 as a renewable non-fossil fuel, a resource with abundant reserves that can be utilized. LH2 does not exist in pure form in nature but can be produced by electrolysis of water (H2O). The liquefied LH2 can be stored in insulated cryogenic tanks for later use. Furthermore, liquid LH2 is first converted to a gaseous state before being transported to a fuel cell, where it reacts with oxygen (as an oxidant) in an electrochemical cell to generate electricity. The byproducts of this reaction are heat and water, which are easily absorbed into the surrounding atmosphere. These characteristics demonstrate that liquid LH2 has the potential to become a viable green energy source.

[0009] Hydrogen can be supplied in both gaseous and liquid forms. Liquid hydrogen has a much lower temperature than other cryogenic liquids, so unique design and material considerations are required when handling liquid hydrogen. For example, LNG (mainly composed of methane) has a boiling point of -162°C (-259°F), while LH2 has a much lower boiling point, reaching -253°C (-423°F).

[0010] Liquid hydrogen has a low boiling point, requiring its storage tanks to have higher insulation performance than other liquid storage tanks. Furthermore, because hydrogen is a very small molecule with low viscosity, LH2 is prone to leakage when stored in tanks or transported by pumps. Therefore, there is an urgent need to improve liquid hydrogen technology, including more efficient and lower-cost liquid hydrogen production processes, improved pumping components and storage systems, and fuel cell engines. Summary of the Invention

[0011] This invention relates to a pump assembly specifically designed for handling and transporting liquid hydrogen (LH2), aiming to overcome the negative drawbacks of LH2 as a green energy source more efficiently. These drawbacks include its low boiling point (the lowest among all industrial gases except helium), and the fact that hydrogen molecules are very small and have low viscosity. Therefore, when LH2 is transported from large storage tanks to rocket engines on launch pads, or to small pressurized storage tanks in refueling stations such as semi-trailer trucks, buses, forklifts, delivery trucks, and passenger cars, leakage is likely to occur. Therefore, the primary objective of this invention is to overcome the various shortcomings in the storage, extraction, and transport of LH2 in insulated storage tanks to small storage tanks used at its final destination, which could be a fuel cell or even an internal combustion engine using liquid LH2. Therefore, this invention discloses an LH2 pump assembly comprising a centrifugal pump, an induction motor, and an integrated vacuum jacket housing. The integrated vacuum jacket housing includes an inlet-side vacuum jacket and a pump vacuum jacket for sealing the centrifugal pump, and a motor vacuum jacket and an exhaust-side vacuum jacket for sealing the induction motor.

[0012] Another object of the present invention is to provide a non-submersible pump assembly without any vacuum jacket housing, which uses process fluid to lubricate and cool the seals and bearings of the pump assembly. The non-submersible pump assembly, with or without any vacuum jacket housing, can generally be horizontally configured for various applications, and is equipped with an offset discharge pipe with a ventilation space at the top to prevent air blockage.

[0013] Another object of the present invention is to provide an embodiment in which the pump assembly is vertically submerged in a cryogenic storage tank filled with LH2, and valves are respectively arranged at the bottom and top of the pump assembly. These valves are configured to draw in LH2 from the bottom of the storage tank and move the LH2 to the top of the storage tank for delivery to the corresponding LH2 application scenario. These submerged embodiments may also include the following: submerging the pump assembly in a collection tank container, the collection tank container being fixed to the cryogenic LH2 storage tank filled with LH2. The collection tank container can be placed in a detachable manner outside the cryogenic LH2 storage tank, or in a non-detachable manner inside the cryogenic LH2 storage tank.

[0014] Other apparatuses, systems, methods, features, and advantages of the present invention will be apparent to those skilled in the art from the following accompanying drawings and detailed descriptions. Such additional systems, methods, features, and advantages are intended to be included within the scope of this specification and are protected by the appended claims. Attached Figure Description

[0015] The invention can be better understood by referring to the following accompanying drawings. The components in the drawings are not necessarily drawn to scale; the focus is on illustrating the principles of the invention. In the drawings, the same reference numerals designate corresponding parts in different views.

[0016] Figure 1 A front perspective view of an exemplary embodiment of an inline cryogenic LH2 pump assembly comprising a centrifugal pump, an induction motor, and an integrated vacuum jacket housing according to the present disclosure is shown.

[0017] Figure 2 The following is shown in accordance with the present disclosure Figure 1 A front perspective view of a cryogenic LH2 pump assembly without the centrifugal pump vacuum jacket and the induction motor vacuum jacket.

[0018] Figure 3 The following is shown in accordance with the present disclosure Figure 1 Lateral cross-sectional view of the medium-low temperature LH2 pump assembly taken along the centerline.

[0019] Figure 4 The following is shown in accordance with the present disclosure Figure 2 Exploded view of the medium-low temperature LH2 pump assembly.

[0020] Figure 5 This illustrates a configuration available for use in accordance with the present disclosure. Figure 1 A front perspective view of an exemplary embodiment of the impeller and guide vanes implemented in a medium-low temperature LH2 pump assembly.

[0021] Figure 6 The following is shown in accordance with the present disclosure Figure 5 Lateral cross-sectional view of the impeller and guide vanes taken along the centerline.

[0022] Figure 7 The following is shown in accordance with the present disclosure Figure 5 Three-dimensional view of the rear of the impeller and guide vanes.

[0023] Figure 8 A front perspective view is shown of another exemplary embodiment of a cryogenic LH2 pump assembly including bayonet joints at the inlet and outlet pipes according to the present disclosure.

[0024] Figure 9 The following is shown in accordance with the present disclosure Figure 8 Lateral cross-sectional view of the medium-low temperature LH2 pump assembly taken along the centerline.

[0025] Figure 10 The following is shown in accordance with the present disclosure Figure 9 Lateral cross-sectional view of the cryogenic LH2 pump assembly coupled to the field adapter.

[0026] Figure 11 A front perspective view of an exemplary embodiment of a cryogenic LH2 pump assembly including an offset discharge pipe and a housing without a vacuum jacket, as described in this disclosure, is shown.

[0027] Figure 12 The following is shown in accordance with the present disclosure Figure 11 A cross-sectional view of the medium-low temperature LH2 pump assembly taken along the centerline.

[0028] Figure 13 A front perspective view of an exemplary embodiment of a cryogenic LH2 pump assembly including a filter screen coupled to the inlet of a collection tank, as described in this disclosure, is shown.

[0029] Figure 14 The following is shown in accordance with the present disclosure Figure 13 A front perspective view of the medium-low temperature LH2 pump assembly and the offset discharge pipe.

[0030] Figure 15 A front perspective view of an exemplary embodiment of a cryogenic LH2 pump assembly having an integrated vacuum jacket housing, a bayonet joint, and an offset discharge pipe according to the present disclosure is shown.

[0031] Figure 16 The following is shown in accordance with the present disclosure Figure 15 A cross-sectional view of the medium-low temperature LH2 pump assembly taken along the centerline.

[0032] Figure 17A A side elevation view of an exemplary embodiment of a cryogenic LH2 pump assembly vertically submerged in a cryogenic LH2 storage tank according to the present disclosure is shown.

[0033] Figure 17B A side elevation view of an exemplary embodiment of the cryogenic LH2 pump assembly according to the present disclosure is shown, the cryogenic LH2 pump assembly being vertically immersed in a collection tank configured to be fixed to a cryogenic LH2 storage tank.

[0034] Figure 18A The diagram shows a side elevation view of an exemplary embodiment of the cryogenic LH2 pump assembly according to the present disclosure, which is vertically oriented and has a vacuum jacket housing and a bayonet joint.

[0035] Figure 18BThe diagram shows a side elevation view of an exemplary embodiment of a cryogenic LH2 pump assembly according to the present disclosure, the cryogenic LH2 pump assembly being vertically oriented and having a vacuum jacket housing, a flanged inlet pipe, and a flanged outlet pipe.

[0036] Figure 18C The diagram shows a side elevation view of an exemplary embodiment of the cryogenic LH2 pump assembly according to the present disclosure, which is vertically oriented, has a vacuum jacket housing, and has a flanged inlet pipe and a flanged outlet pipe.

[0037] Figure 18D The diagram shows a side elevation view of an exemplary embodiment of the cryogenic LH2 pump assembly according to the present disclosure, which is vertically oriented, has a vacuum jacket housing, and includes a liquid collection tank inlet pipe and a flanged outlet pipe.

[0038] Figure 18E The diagram shows a side elevation view of an exemplary embodiment of the cryogenic LH2 pump assembly according to the present disclosure, which is vertically oriented, has a vacuum jacket housing, and includes a liquid collection tank inlet pipe and an offset flange outlet pipe.

[0039] Figure 18F The diagram shows a side elevation view of an exemplary embodiment of the cryogenic LH2 pump assembly according to the present disclosure, which is horizontally oriented, has a vacuum jacketed housing, and features an offset bayonet joint.

[0040] Figure 18G The diagram shows a side elevation view of an exemplary embodiment of the cryogenic LH2 pump assembly according to the present disclosure, which is horizontally oriented, has a vacuum-jacketed housing, and has a flanged inlet pipe and an offset flanged outlet pipe. Detailed Implementation

[0041] The following description of preferred and alternative embodiments will be made with reference to the accompanying drawings, which form part of this invention, and illustrate specific embodiments in which the invention can be practically implemented. It should be understood that other implementation methods may be employed, and various structural changes may be made without departing from the spirit and scope of the invention.

[0042] Figure 1 An exemplary embodiment of a cryogenic LH2 pump assembly 100 (hereinafter referred to as "pump assembly 100") surrounded by an integral vacuum jacket housing according to the present disclosure is shown. Pump assembly 100 includes a centrifugal pump 104, which is connected by a plurality of fasteners 112 and a pump pull rod 164 (see...). Figure 2 The centrifugal pump 104 is coupled to an induction motor 108. The centrifugal pump 104 includes an inlet pipe 116, which is configured to allow the centrifugal pump 104 to draw in LH2. Figure 1 In the illustrated embodiment, the inlet pipe 116 includes an inlet flange 120 configured to couple the inlet pipe 116 to the LH2 source. The induction motor 108 includes a discharge pipe 124 configured to allow LH2 to be discharged from the centrifugal pump 104. Figure 1 In the illustrated embodiment, the discharge pipe 124 includes a discharge flange 128, which is configured to allow coupling of the discharge pipe 124 to downstream equipment without any limitations.

[0043] As described above, the pump assembly 100 is surrounded by a vacuum jacket housing. More specifically, the centrifugal pump 104 is disposed within the inlet-side vacuum jacket 132 and the pump vacuum jacket 136, and the induction motor 108 is disposed within the motor vacuum jacket 140 and the discharge-side vacuum jacket 144 (see [link to documentation]). Figure 3 ).like Figure 1 As shown, the pump and motor vacuum jackets 136 and 140 are engaged via a vacuum jacket connector 148. The vacuum jacket housing is configured to minimize heat loss around the centrifugal pump 104 due to the extremely low temperature of LH2. It is envisioned that the vacuum jacket housing further eliminates the need for cooling the centrifugal pump 104 by placing the pump assembly 100 within a collection tank or column. Since the pump assembly 100 is surrounded by the vacuum jacket housing, the cooling status of the centrifugal pump 104 cannot be monitored. Therefore, it is envisioned that an integrated temperature monitoring device be embedded in the motor windings, including the induction motor 108.

[0044] Figure 2 A pump assembly 100 without a vacuum jacket housing according to this disclosure is shown. The pump assembly 100 can be vertically mounted as a submersible cryogenic LH2 pump assembly in an insulated cryogenic storage tank containing LH2, or it can be configured to operate without immersion in the storage tank by providing process fluid to lubricate the bearings of the pump assembly 100 through internal flow channels. Figure 2 As shown, inlet pipe 116 is coupled to inlet manifold 168, which is in fluid communication with the suction side of centrifugal pump 104 and configured to supply LH2 to centrifugal pump 104. Centrifugal pump 104 is fastened to intermediate coupling manifold 160 via a plurality of pump rods 164, which are threaded into holes (not shown) provided on the inlet side of coupling manifold 160. Fastener 112 also couples inlet manifold 168 to suction port of centrifugal pump 104 via pump rods 164. In one embodiment, fastener 112 includes hexagonal nuts and / or hexagonal lock nuts, which are secured to the threaded fastening end of pump rod 164 passing through the hole (not shown) in inlet manifold 168 and configured to prevent pump rod 164 from loosening when tightened.

[0045] The induction motor 108 is fixed to the coupling manifold 160 by a plurality of motor tie rods 172, which are fastened between the coupling manifold 160 and the discharge manifold 176 including the pump assembly 100. Figure 2 In the illustrated embodiment, one coupling end of each motor pull rod 172 is threaded into a hole (not shown) located on the outlet side of the coupling manifold 160, while the opposite fastener end of the motor pull rod 172 is secured to the discharge manifold 176 by a fastener 180. In one embodiment, the fastener 180 includes a hex nut and / or a hex lock nut, which are secured to the threaded fastener end of the motor pull rod 172 passing through the hole (not shown) in the discharge manifold 176 and configured to prevent the motor pull rod 172 from loosening when tightened.

[0046] See Figure 4 This embodiment shows eight fasteners 112 located in the inlet manifold 168 and eight fasteners 180 located near the outlet manifold 176. Therefore, in this embodiment, there will be eight pump rods 164 and eight motor rods 172. In other embodiments, any number of pump rods and motor rods may be present depending on the size of the pump and motor and other factors.

[0047] like Figure 2 As shown, a plurality of longitudinal discharge pipes 184 are provided between the coupling manifold 160 and the discharge manifold 176. As described in this invention, the coupling manifold 160 is configured to guide LH2 received from the centrifugal pump 104 into the longitudinal discharge pipes 184. The LH2 is pumped through the longitudinal discharge pipes 184 to the discharge manifold 176. The discharge manifold 176 merges the LH2 flows received from the plurality of longitudinal discharge pipes 184 into a single LH2 flow, which is then discharged from the pump assembly 100 through the discharge pipe 124. Figure 2 In the illustrated embodiment, four longitudinal discharge pipes 184 are evenly arranged around the circumference of the pump assembly 100 at 90-degree intervals. However, it is contemplated that in some embodiments, any number of longitudinal discharge pipes 184 can be arranged around the circumference of the pump assembly 100 at any interval of various sizes, without any limitation.

[0048] Figure 3 The following is shown in accordance with the present disclosure Figure 1 The pump assembly 100 shown is a lateral cross-sectional view taken along its centerline. (See diagram below.) Figure 3As shown, the pump assembly 100 is surrounded by a vacuum jacket housing configured to minimize heat loss from the pump assembly 100 to the surrounding environment. The vacuum jacket housing includes an inlet-side vacuum jacket 132, a pump vacuum jacket 136, a motor vacuum jacket 140, and a discharge-side vacuum jacket 144. Further, an inlet vacuum jacket 188 surrounds an inlet pipe 116, while a discharge vacuum jacket 192 surrounds a discharge pipe 124. Thus, the inlet pipe 116 and the surrounding inlet vacuum jacket 188 provide a coaxial inlet connection for the pump assembly 100, while the discharge pipe 124 and the surrounding discharge vacuum jacket 192 provide a coaxial discharge connection for the pump assembly 100. It is envisioned that the coaxial inlet and discharge connections will minimize the required auxiliary equipment, making the installation of the pump 100 easier. Further, in some embodiments, the pump assembly 100 may include a bayonet joint as described below.

[0049] like Figure 3-4 As shown, the pump assembly 100 includes a single motor / pump shaft 196 that extends from the induction motor 108 through the centrifugal pump 104. Figure 4 As shown, the motor / pump shaft 196 is supported by bearings 200 (each end of the motor commutator 204 has a bearing), and is therefore configured to rotate within the pump assembly 100. The motor commutator 204 is mounted on the motor / pump shaft 196 and is configured to be driven to rotate by the motor stator 208 located within the induction motor 108. Further, as Figure 4 As shown, the motor stator 208 is surrounded by a longitudinal discharge pipe 184. The induction motor 108 is cooled by an internal flow channel disposed inside the induction motor 108 and located between the coupling manifold and the discharge manifold. In some embodiments, the temperature of the induction motor 108 can be monitored by an integrated temperature sensor embedded in the motor stator 208.

[0050] like Figure 3-4As shown in the optimal configuration, the motor / pump shaft 196 extends through the centrifugal pump 104 to the inlet manifold 168. An inducer 212 is mounted at the end of the motor / pump shaft 196 and located within the inlet pipe 116. A first impeller 216, coupled to the motor / pump shaft 196, is located behind the inducer 212. The first impeller 216 rotates relative to a first guide vane 220, which is fixedly coupled to a first guide vane housing 224. The first impeller 216 and the first guide vane 220 are adjusted to efficiently move LH2 from the inlet pipe 116 to a second impeller 228, which rotates relative to a second guide vane 232. The second guide vane 232 is fixedly coupled to a second guide vane housing 236. The second impeller 228 and the second guide vane 232 are configured to efficiently move LH2 beyond the second guide vane housing 236, reaching a third impeller 240. The third impeller 240 rotates relative to a third guide vane 244, which is fixedly coupled to the front of the coupling manifold 160 (see...). Figure 4 Therefore, the third impeller 240 and the third guide vane 244 can be adjusted to efficiently move LH2 into the coupling manifold 160.

[0051] Continue to refer to Figure 3 The LH2 discharged by centrifugal pump 104 is pumped to coupling manifold 160. More specifically, coupling manifold 160 includes an annular cavity 248, configured to transfer LH2 received from the third impeller and guide vanes 240, 244 to longitudinal discharge pipe 184. Figure 4 In the illustrated embodiment, four longitudinal discharge pipes 184 are evenly arranged around the circumference of the motor stator 208 at 90-degree intervals. Given that the annular cavity 248 establishes fluid communication between the third impeller and guide vanes 240, 244 and each longitudinal discharge pipe 184, it should be understood that in the illustrated embodiment, the annular cavity 248 is configured to combine all process fluids from the third guide vane 244 into a single flow for transmission to the longitudinal discharge pipes 184 of the induction motor. However, it is contemplated that in some embodiments, the annular cavity 248 can be arranged within the coupling manifold 160 in any manner, as long as fluid communication is established between the third impeller and guide vanes 240, 244 and the longitudinal discharge pipes 184, and the number of longitudinal discharge pipes 184 can vary without any limitation.

[0052] In addition, such as Figure 3 As shown, the discharge manifold 176 includes lateral discharge channels 252 configured to transmit LH2 received from the longitudinal discharge channels 184 to the discharge channel 124. Each lateral discharge channel 252 extends radially inward within the discharge manifold 176 to the discharge channel 124. According to the invention, given that four longitudinal discharge channels 184 are evenly arranged around the circumference of the motor stator 208 at 90-degree intervals, it should be understood that... Figure 3-4In the illustrated embodiment, four transverse discharge channels 252 are arranged circumferentially around the discharge manifold 176 at 90-degree intervals and are in fluid communication with the discharge pipe 124. In some embodiments, any number of transverse discharge channels 252 can be arranged in any manner within the discharge manifold 176, as long as fluid communication can be established between the longitudinal discharge pipe 184 and the discharge pipe 124, without any limitation.

[0053] Continue to refer to Figure 3 The centrifugal pump 104 of the pump assembly 100 is a three-stage multistage centrifugal pump, in which the flow rate and head of LH2 increase as it flows through each stage of the pump body. Each stage consists of impeller-guide vane pairs, specifically the first-stage impeller-guide vane pairs 216 and 220, the second-stage impeller-guide vane pairs 228 and 232, and the third-stage impeller-guide vane pairs 240 and 244. The disadvantages of multistage centrifugal pumps include higher initial costs, more complex installation due to the multiple stages, increased energy consumption due to high-pressure operation, and increased weight of the centrifugal pump 104. Therefore, for some applications, a single-stage centrifugal pump can be selected. On the other hand, multistage centrifugal pumps offer a flexible range of flow rates and head, and have a higher energy efficiency rating, so any number of stages can be used—two, three, four, or any other number of stages.

[0054] Please turn to the next page. Figure 5-7 The figure shows impeller 260 and guide vane 264. Impeller 260 and guide vane 264 can be configured in centrifugal pump 104, see [reference]. Figure 1-4 Therefore, it should be understood that the impeller 260 and guide vane 264 are substantially the same as each impeller-guide vane pair in the first-stage, second-stage, and third-stage impeller-guide vane pairs described above in this invention.

[0055] Typically, the impeller 260 is configured to rotate, while the guide vane 264 remains fixed to the guide vane housing, which includes the centrifugal pump 104, for example... Figure 4 The first guide vane housing 224 is shown. The guide vane 264 includes a hole 266 (see...). Figure 6 and Figure 7 The bore 266 is configured to accommodate fasteners, thereby securing the guide vane 264 to the guide vane housing 224. The impeller 260 includes a central bore 268 that accommodates the motor / pump shaft 196 (see...). Figure 4 A blade 272 is used to rotate the impeller 260. The impeller 260 includes blades 272 configured to draw in LH2 in the central region of the impeller 260 and radially propel LH2 to a circumferential opening 276 disposed around the circumference of the impeller 260. It is envisioned that the configuration of the blades 272 and the circumferential opening 276 is adapted to the unique properties of LH2 to achieve efficient operation.

[0056] It should be understood that the LH2 discharged from the circumferential opening 276 of the impeller 260 enters the guide vane 264, the blades 280 arranged on the guide vane 264, and the guide vane housing 224 tightly fitted onto the guide vane 264. The blades 280 are arranged on the guide vane 264 such that the cross-sectional area through which the LH2 flows as it moves around the guide vane 264 is increased. It is envisioned that the configuration of the blades 280 is adapted to the unique properties of the LH2 to achieve efficient operation.

[0057] Figure 8 An exemplary embodiment of an LH2 pump assembly 300 (hereinafter referred to as "pump assembly 300") surrounded by a vacuum jacket housing according to the present disclosure is shown. Figure 8 The pump assembly 300 shown is Figure 1 The pump assembly 100 shown is basically similar, except that the pump assembly 300 includes the bayonet connector described in this invention.

[0058] Pump assembly 300 includes a centrifugal pump 304, which is coupled to an induction motor 308 via a plurality of fasteners 312. Centrifugal pump 304 includes an inlet pipe 316 configured to allow pump assembly 300 to draw in LH2. Figure 8 In the illustrated embodiment, the inlet pipe 316 includes a bayonet connector 320 configured to couple the inlet pipe 316 to an LH2 source. The induction motor 308 includes a discharge pipe 324 configured to allow LH2 to be discharged from the pump assembly 300. Figure 8 In the embodiment shown, the discharge pipe 324 includes a bayonet connector 328, which is configured to enable coupling between the discharge pipe 324 and downstream equipment without any limitations.

[0059] As described above, the pump assembly 300 is surrounded by a vacuum jacket housing. More specifically, the centrifugal pump 304 is disposed within the inlet-side vacuum jacket 332 and the pump vacuum jacket 336. The induction motor 308 is disposed within the motor vacuum jacket 340 and the discharge-side vacuum jacket 344 (see [link to relevant documentation]). Figure 9 ).like Figure 8 As shown, the pump and motor vacuum jackets 336 and 340 are engaged via vacuum jacket connector 348. Further, the inlet pipe vacuum jacket 352 surrounds the inlet pipe 316, while the outlet pipe vacuum jacket 356 (see...) Figure 9 The inlet pipe 316 and the vacuum jacket 352 surrounding the inlet pipe provide a coaxial inlet connection for the pump assembly 300, while the outlet pipe 324 and the vacuum jacket 356 surrounding the outlet pipe provide a coaxial outlet connection for the pump assembly 300. Further, as... Figure 10As shown, the field adapter 360 can be coupled to each bayonet connector 328, 320. It is envisioned that the coaxial inlet and outlet connections, along with the field adapter 360, will minimize the required auxiliary equipment, making the installation of the pump assembly 300 easier.

[0060] Figure 11 An exemplary embodiment of a pump assembly 400 without a vacuum jacket housing according to this disclosure is shown. The pump assembly 400 and... Figure 2 The pump assembly 100 shown is substantially similar, except that pump assembly 400 includes an offset discharge pipe 404 to prevent airlock. Similar to pump assembly 100, pump assembly 400 includes a centrifugal pump 408 rigidly connected to an induction motor 412. Pump 408 includes an inlet pipe 416 configured to allow pump assembly 400 to draw in LH2. Figure 11 In the illustrated embodiment, the inlet pipe 416 includes an inlet flange 420 configured to couple the inlet pipe 416 to the LH2 source. The induction motor 412 includes a biased discharge pipe 404 configured to allow LH2 to be discharged from the pump assembly 400. Figure 11 In the embodiment shown, the discharge pipe 404 includes a discharge flange 428, which is configured to enable the offset discharge pipe 404 to couple with downstream equipment without any limitations.

[0061] like Figure 11-12 As shown, the pump assembly 400 includes an inlet manifold 432, a coupling manifold 436, and a discharge manifold 440. A plurality of longitudinal discharge pipes 444 are disposed between the coupling manifold 436 and the discharge manifold 440. As described in this invention, the coupling manifold 436 can guide LH2 received from the pump 408 into the longitudinal discharge pipes 444. The LH2 is pumped to the discharge manifold 440 through the longitudinal discharge pipes 444. The discharge manifold 440 merges the LH2 flows received from the plurality of longitudinal discharge pipes 444 into a single LH2 flow, which is then discharged from the pump assembly 400 through an offset discharge pipe 404. Figure 11-12 In the illustrated embodiment, four longitudinal discharge pipes 444 are evenly arranged around the circumference of the pump assembly 400 at 90-degree intervals. However, it is contemplated that in some embodiments, any number of longitudinal discharge pipes 444 can be arranged around the circumference of the pump assembly 400 in any of various arrangements without any limitation.

[0062] Figure 13 An exemplary embodiment of a pump assembly 500 without a vacuum jacket housing according to this disclosure is shown. The pump assembly 500 and... Figure 2The pump assembly 100 shown is substantially similar, except that the pump assembly 500 includes a filter 504 coupled to a collection tank inlet 508. Similar to pump assembly 100, pump assembly 500 includes a centrifugal pump 508 securely connected to an induction motor 512. Centrifugal pump 508 includes an inlet pipe 516 configured to allow pump assembly 500 to draw in LH2. Figure 13 In the illustrated embodiment, the inlet pipe 516 includes a collection tank inlet 508, configured to allow the pump assembly 500 to be submerged in a relatively large LH2 storage tank. The motor 512 includes a discharge pipe 520, configured to allow LH2 to be discharged from the pump assembly 500. Figure 13 In the illustrated embodiment, the discharge pipe 520 includes a discharge flange 524, which is configured to allow coupling of the discharge pipe 520 to downstream equipment without any limitations.

[0063] Continue to refer to Figure 13 The pump assembly 500 includes an inlet manifold 532, a coupling manifold 536, and a discharge manifold 540. A plurality of longitudinal discharge pipes 544 are disposed between the coupling manifold 536 and the discharge manifold 540. As described in this invention, the coupling manifold 536 can guide LH2 received from the pump assembly 508 into the longitudinal discharge pipes 544. The LH2 is pumped through the longitudinal discharge pipes 544 to the discharge manifold 540. The discharge manifold 540 merges the LH2 flows received from the longitudinal discharge pipes 544 into a single LH2 flow, which is then discharged from the pump assembly 500 through a discharge pipe 520. Figure 13 In the illustrated embodiment, four longitudinal discharge pipes 544 are evenly arranged around the circumference of the pump assembly 500 at 90-degree intervals. However, it is contemplated that in some embodiments, any number of longitudinal discharge pipes 544 can be arranged around the circumference of the pump assembly 500 in any of various arrangements without any limitation.

[0064] Figure 14 An exemplary embodiment of a pump assembly 600 without a vacuum jacket housing according to this disclosure is shown. The pump assembly 600 is substantially similar to the pump assembly 400, as... Figure 11-12 As shown, the difference lies in that pump assembly 600 includes a filter 604 coupled to the liquid inlet 608 of the collection tank. Similar to pump assembly 400, pump assembly 600 includes a pump 612, which is rigidly connected to an induction motor 616. Centrifugal pump 612 includes an inlet pipe 620, configured to allow pump assembly 600 to draw LH2 in through inlet manifold 632. Figure 14 In the illustrated embodiment, the inlet pipe 620 includes a collection tank inlet 608, allowing the pump assembly 600 to be submerged in a relatively large LH2 cryogenic tank. The induction motor 616 includes a biased discharge pipe 624, configured to allow LH2 to be discharged from the pump 600. Figure 14In the illustrated embodiment, the biased discharge pipe 624 includes a discharge flange 628, which is configured to enable coupling of the biased discharge pipe 624 to downstream equipment without any limitations.

[0065] like Figure 14 As shown, the pump assembly 600 includes an inlet manifold 632, a coupling manifold 636, and a discharge manifold 640. A plurality of longitudinal discharge pipes 644 are disposed between the coupling manifold 636 and the discharge manifold 640. As described in this invention, the coupling manifold 636 can guide LH2 received from the centrifugal pump 612 into the longitudinal discharge pipes 644. The LH2 is pumped to the discharge manifold 640 through the longitudinal discharge pipes 644. The discharge manifold 640 merges the LH2 flow received from the longitudinal discharge pipes 644 into a single LH2 flow, which is then discharged from the pump assembly 600 through an offset discharge pipe 624. Figure 14 As shown, four longitudinal discharge pipes 644 are evenly arranged around the circumference of the pump assembly 600 at 90-degree intervals. However, as mentioned above, in some embodiments, any number of longitudinal discharge pipes 644 can be arranged around the circumference of the pump assembly 600 in any of various arrangements without any limitation.

[0066] Figure 15 An exemplary embodiment of a pump assembly 700 with an integrated vacuum jacket housing according to the present disclosure is shown. The pump assembly 700 and... Figure 8 The pump assembly 300 shown is substantially similar, except that pump assembly 700 includes an offset discharge pipe 724. Similar to pump assembly 100, pump assembly 700 includes a centrifugal pump 704 rigidly connected to an induction motor 708. Pump 704 includes an inlet pipe 716, configured to allow pump assembly 700 to draw in LH2. Figure 15 In the illustrated embodiment, the inlet pipe 716 includes a bayonet connector 720 configured to facilitate coupling of the inlet pipe 716 to an LH2 source. The induction motor 708 includes a biased discharge pipe 724 configured to allow LH2 to be discharged from the pump assembly 700. Figure 16 It shows Figure 15 A cross-sectional view of the medium-low temperature LH2 pump assembly taken along the centerline is disclosed, and the offset discharge pipe 724 is disclosed to provide vertical offset to facilitate operation of the pump assembly 700 with a horizontal configuration.

[0067] Figure 17A A side elevation view of an exemplary embodiment of a cryogenic LH2 pump assembly 820 vertically immersed in an insulated cryogenic LH2 storage tank 800 according to the present disclosure is shown. The LH2 contained in the LH2 storage tank 800 reaches a liquid level L, and the space S between the liquid level L and the top 828 of the LH2 storage tank 800 is filled with gas evaporated from the liquid LH2. The LH2 storage tank 800 includes an insulating wall 850, a discharge pipe 830, and a shell 860.

[0068] Figure 17B A side elevation view of an exemplary embodiment of a cryogenic LH2 pump assembly vertically immersed in a collection chamber 826 of a collection tank 810 according to the present disclosure is shown, the cryogenic LH2 pump assembly including an inlet pipe 824 and an outlet pipe 840.

[0069] Figure 18A A side elevation view of an exemplary embodiment of a cryogenic LH2 pump assembly 900 including a vacuum jacket housing according to the present disclosure is shown. The cryogenic LH2 pump assembly 900 has a vertical configuration and includes an inlet pipe 960, an outlet pipe 964, and a bayonet connector 966.

[0070] Figure 18B A side elevation view of another exemplary embodiment of a cryogenic LH2 pump assembly 900 including a vacuum jacket housing according to the present disclosure is shown. The cryogenic LH2 pump assembly 900 has a vertical configuration and includes a flanged inlet pipe 930 and a flanged outlet pipe 932.

[0071] Figure 18C A side elevation view of another exemplary embodiment of a cryogenic LH2 pump assembly 920 without a vacuum jacket housing according to the present disclosure is shown. The cryogenic LH2 pump assembly 920 has a vertical configuration and includes a flanged inlet pipe 930 and a flanged outlet pipe 940.

[0072] Figure 18D A side elevation view of another exemplary embodiment of a cryogenic LH2 pump assembly 920 without a vacuum jacket housing according to the present disclosure is shown. The cryogenic LH2 pump assembly 920 has a vertical configuration and includes a liquid collection tank inlet 934 and a flanged outlet pipe 940.

[0073] Figure 18E A side elevation view of another exemplary embodiment of a cryogenic LH2 pump assembly 920 without a vacuum jacket housing according to the present disclosure is shown. The cryogenic LH2 pump assembly 920 has a vertical configuration and includes a collection tank inlet 934 and a flanged offset outlet pipe 950.

[0074] Figure 18F The diagram shows a side elevation view of an exemplary embodiment of a cryogenic LH2 pump assembly 900 including a vacuum jacket housing according to the present disclosure, the cryogenic LH2 pump assembly 900 having a horizontal configuration and including an inlet pipe 970, an offset outlet pipe 974, and a bayonet connector 978.

[0075] Figure 18GA side elevation view of another exemplary embodiment of a cryogenic LH2 pump assembly 920 without a vacuum jacket housing according to the present disclosure is shown. The cryogenic LH2 pump assembly 920 has a horizontal configuration and includes a flanged inlet pipe 930 and a flanged offset outlet pipe 950.

Claims

1. An inline coaxial cryogenic liquid hydrogen (LH2) pump assembly, comprising: Centrifugal pumps have an inlet side and an outlet side; An induction motor, having an inflow side and an outflow side, is coupled to the centrifugal pump; Vacuum jacket housing, comprising: An inlet-side vacuum jacket and a pump vacuum jacket are used to seal the centrifugal pump; The electric motor vacuum jacket and the exhaust port side vacuum jacket are used to seal the induction motor; Vacuum jacket connector, used to connect the vacuum jacket of a centrifugal pump and the vacuum jacket of an induction motor; The inlet pipe is coupled to the inlet side of the centrifugal pump; The discharge pipe is coupled to the outflow side of the induction motor.

2. The inline coaxial cryogenic LH2 pump assembly according to claim 1, further comprising: An inlet flange fixed to the front end of the inlet pipe is configured to allow the inlet pipe to be connected to an LH2 source. An exhaust flange is fixed to the rear end of the exhaust pipe, and the exhaust flange is configured to couple the exhaust pipe to downstream auxiliary equipment.

3. The inline coaxial cryogenic LH2 pump assembly according to claim 2, further comprising: An inlet manifold that is in fluid communication with the inlet side of the centrifugal pump is configured to provide LH2 from an LH2 source to the centrifugal pump by itself. A coupling manifold having an inlet side and an outlet side, wherein the inlet side of the coupling manifold is configured to transmit LH2 from the outlet side of the centrifugal pump to the inflow side of the discharge manifold through multiple longitudinal discharge pipes, wherein the inflow side of the discharge manifold is coupled to the outflow side of the longitudinal discharge pipes, and the outflow side of the discharge manifold is coupled to the discharge pipes.

4. The inline coaxial cryogenic LH2 pump assembly according to claim 3, wherein, The centrifugal pump and the induction motor are fixed to each other by a plurality of pump rods symmetrically arranged around the inlet manifold and the coupling manifold. Each pump rod has a coupling end with an external thread, which can be threaded to one of a plurality of equally spaced holes on the outer periphery of the inlet side of the coupling manifold. Each pump rod also has a fastener end with an external thread, which is configured to accommodate and fix a fastener, such as a hexagonal nut and / or a hexagonal lock nut. The fastener is fixed to the fastener end after passing through a corresponding hole in one of the plurality of equally spaced holes on the outer periphery of the inlet manifold. The induction motor and the exhaust manifold are fixed to each other by a plurality of motor tie rods symmetrically arranged around the coupling manifold and the exhaust manifold. Each motor tie rod has a coupling end with an external thread, which can be threaded to one of a plurality of equidistant holes on the outer periphery of the outlet side of the coupling manifold. Each motor tie rod also has a fastener end with an external thread, which is configured to accommodate and fix a fastener, such as a hexagonal nut and / or a hexagonal lock nut. The fastener is fixed to the fastener end after passing through a corresponding hole in the plurality of equidistant holes on the outer periphery of the exhaust manifold.

5. The inline coaxial cryogenic LH2 pump assembly according to claim 1, wherein, The centrifugal pump includes: A single motor / pump shaft extends through the centrifugal pump from the induction motor to the inlet pipe and is supported by a pair of bearings disposed in the induction motor, thereby supporting the centrifugal pump and the induction motor to rotate within the LH2 pump assembly.

6. The inline coaxial cryogenic LH2 pump assembly according to claim 1, wherein, The induction motor includes a commutator mounted on the motor / pump shaft, the commutator being configured to be driven to rotate by a motor stator disposed inside the induction motor.

7. The inline coaxial LH2 pump assembly according to claim 1, comprising: An inlet bayonet connector fixed to the outer end of the inlet pipe, the inlet bayonet connector being configured to connect the inlet pipe to an LH2 source; and An outlet bayonet connector is fixed to the outer end of the discharge pipe, and the outlet bayonet connector is configured to allow the discharge pipe to be connected to downstream auxiliary equipment.

8. The inline coaxial cryogenic LH2 pump assembly according to claim 5, wherein, The centrifugal pump further includes: The inducer wheel is mounted on the motor / pump shaft and located inside the inlet pipe; Multiple stage units, each stage unit including an impeller coupled to a motor / pump shaft and rotating relative to a guide vane coupled to a guide vane housing that simultaneously encloses the impeller and the guide vane, except for the final stage unit, which is directly coupled to a coupling manifold. LH2 flows sequentially through each stage unit, reducing the flow velocity and increasing the head through each stage unit, and moves efficiently to the coupling manifold coupled to the discharge pipe.

9. The inline coaxial cryogenic LH2 pump assembly according to claim 8, wherein, Each guide vane of the centrifugal pump includes blades fixed on the guide vane, such that the cross-sectional area of ​​LH2 flowing through the stage unit gradually increases as it passes through and around the corresponding guide vane, thereby increasing the pressure head of LH2.

10. The inline coaxial cryogenic LH2 pump assembly according to claim 7, wherein, The first field adapter is coupled to the inlet bayonet connector, and the second field adapter is coupled to the outlet bayonet connector.

11. The inline coaxial LH2 centrifugal pump assembly according to claim 6, wherein, The motor stator is surrounded by multiple longitudinal discharge pipes, which are evenly arranged around the circumference of the motor stator and are in fluid communication with the discharge manifold, which is coupled to the discharge pipes.

12. An inline coaxial liquid hydrogen (LH2) pump assembly, comprising: Centrifugal pump; An induction motor coupled to the centrifugal pump; The inlet pipe is coupled to the centrifugal pump; The discharge pipe is coupled to the induction motor.

13. The inline coaxial cryogenic LH2 pump assembly according to claim 12, wherein, The annular cavity in the coupling manifold is configured to collect all LH2 from the final stage guide vanes of the centrifugal pump and transmit it to multiple longitudinal discharge pipes evenly spaced around the stator of the induction motor. The stator of the induction motor is embedded with an integrated temperature sensor for monitoring temperature.

14. The inline coaxial LH2 pump assembly according to claim 12, wherein, The induction motor and bearings are cooled by an internal flow channel located inside the induction motor and between the coupling manifold and the exhaust manifold.

15. The inline coaxial LH2 pump assembly according to claim 12, wherein the assembly is configured for horizontal operation and can be installed in a fixed or vehicle-mounted configuration, wherein... The discharge pipe is configured as an offset discharge pipe to prevent air blockage.

16. A submersible cryogenic liquid hydrogen (LH2) pump assembly, particularly suitable for extracting LH2 from an insulated cryogenic storage tank containing LH2, wherein, The submersible cryogenic LH2 pump assembly is configured to be vertically submerged in an LH2 cryogenic storage tank. The submersible LH2 pump assembly includes: A centrifugal pump, including an inlet pipe and a collection tank inlet, wherein the collection tank inlet is configured to allow the LH2 pump assembly to draw LH2 from a cryogenic LH2 storage tank. An induction motor coupled to the centrifugal pump, the induction motor including a discharge manifold and a discharge pipe.

17. The submersible cryogenic LH2 pump assembly according to claim 16, wherein, The submersible cryogenic LH2 pump assembly is vertically submerged in the collection tank container.

18. The submersible cryogenic LH2 pump assembly according to claim 17, wherein, The liquid collection tank container is located outside the cryogenic LH2 storage tank and is detachable relative to the cryogenic LH2 storage tank.

19. The submersible cryogenic LH2 pump assembly according to claim 17, wherein, The liquid collection tank container is located inside the cryogenic LH2 storage tank and is not removable relative to the cryogenic LH2 storage tank.

20. The submersible cryogenic LH2 pump assembly according to claim 16, further comprising a filter screen coupled to an inlet pipe, the inlet pipe being coupled to the suction side of the centrifugal pump.

Images