CN111997862B

CN111997862B - Double-acting reciprocating submerged liquid hydrogen pump

Info

Publication number: CN111997862B
Application number: CN202010715588.4A
Authority: CN
Inventors: 刘海山; 陈正文; 巴胜富; 操松林; 鲁飞; 王永强; 刘广兵; 庞雷; 张的
Original assignee: HEFEI GENERAL ENVIRONMENT CONTROL TECHNOLOGY CO LTD; Hefei General Machinery Research Institute Co Ltd
Current assignee: HEFEI GENERAL ENVIRONMENT CONTROL TECHNOLOGY CO LTD; Hefei General Machinery Research Institute Co Ltd
Priority date: 2020-07-23
Filing date: 2020-07-23
Publication date: 2023-02-28
Anticipated expiration: 2040-07-23
Also published as: CN111997862A

Abstract

The invention discloses a double-acting reciprocating submerged liquid hydrogen pump, which comprises the following components: the isolating part is connected with the liquid hydrogen container, and the pump main body is arranged in the isolating part; the cold end part of the pump main body and the power part connected with the cold end part are arranged on the pump main body; the cold end part comprises a cold end cylinder body, a cold end piston which is divided into an upper cold end cylinder body cavity and a lower cold end cylinder body cavity is arranged in the cold end cylinder body, and an isolation valve of the isolation part is arranged on the lower side of the cold end cylinder body; the upper cavity of the cold end cylinder body is communicated with the isolating valve of the isolating part through an upper cavity suction pipe and is also connected with the liquid hydrogen outlet pipe through an upper cavity discharge pipe; the lower cavity of the cold end cylinder body is communicated with the isolation valve through a lower cavity inlet one-way valve and is also connected with a liquid hydrogen outlet pipe through a lower cavity outlet one-way valve. The invention not only cancels the pre-cooling step before working, but also has the function of conveying liquid hydrogen when the cold end reciprocates up and down, thereby greatly improving the working efficiency, and the liquid hydrogen conveying capacity is large and the output flow pulsation characteristic is better.

Description

Double-acting reciprocating submerged liquid type liquid hydrogen pump

Technical Field

The invention relates to the field of liquid hydrogen energy, in particular to a double-acting reciprocating submerged liquid type liquid hydrogen pump.

Background

Liquid hydrogen (LH 2) is a high-energy and ultralow-temperature liquid clean fuel, has incomparable advantages in terms of energy storage density and transportation cost compared with gas hydrogen and metal hydride, has a wider development space, and China also issues a plurality of related policies to support the hydrogen energy industry. The liquid hydrogen pump for conveying liquid hydrogen is one of important devices in the liquid hydrogen industry.

At present, the discharge and the transportation of liquid hydrogen basically adopt a pressurizing extrusion mode, the design requirement of a container is high, the output pressure is low, and the high-temperature pressurized gas can generate the risk of thermoacoustic oscillation.

In a common reciprocating type ultra-low temperature pump, a normal temperature power part generally adopts a crank link mechanism driven by a motor, and a cold end of the pump is a plunger pump structure in a vacuum heat insulation mode, and the pump is common equipment for low temperature liquid such as Liquefied Natural Gas (LNG). The method is characterized in that deep precooling is needed before a pump is started, the preparation work is complicated and long-time consuming, and the loss of BOG (low-temperature liquid obtained by liquefying gas under the critical temperature after pressurization is large, and the gas is evaporated due to the fact that the gas is difficult to be absolutely insulated from the environment and absorbs external heat) is large, so that the air is polluted and the cost is increased. In LNG storage and transportation, an electric centrifugal pump completely latent in liquid exists, but the problem of motor liquid immersion cannot be solved because the liquid hydrogen temperature (-253 ℃) is far lower than that of LNG (-169 ℃), so that the solution is needed.

Disclosure of Invention

In order to avoid and overcome the technical problems in the prior art, the invention provides a double-acting reciprocating submerged liquid hydrogen pump. The invention not only cancels the pre-cooling step before work, but also can drive the normal temperature piston through high pressure fluid to drive the cold end to reciprocate and complete the liquid hydrogen conveying process, and has the function of conveying the liquid hydrogen when the cold end reciprocates up and down, thereby greatly improving the work efficiency, and the liquid hydrogen conveying capacity is large and the output flow pulsation characteristic is better.

In order to achieve the purpose, the invention provides the following technical scheme:

a double-acting type reciprocating submerged liquid hydrogen pump comprises the following components:

an isolation part connected with the liquid hydrogen container, wherein the isolation part completely isolates the pump main body from the liquid hydrogen container, and the pump main body is arranged in the isolation part;

a cold end of the pump body for receiving liquid hydrogen from the liquid hydrogen container and discharging the liquid hydrogen to a liquid hydrogen outlet pipe;

the power part is connected with the cold end part and drives the cold end part to reciprocate by adopting high-pressure fluid in the power source station so as to realize the discharge of liquid hydrogen;

the cold end part comprises a cold end cylinder body, a cold end piston connected with the power part through a support rod is arranged in the cold end cylinder body, and a cold end piston sealing ring used for filling a gap between the cold end piston and the inner wall of the cylinder body is sleeved on the periphery of the cold end piston; the lower side of the cold end cylinder body is provided with an isolation valve which is used for communicating or separating the lower cavity of the cold end cylinder body on the lower side of the cold end piston with the liquid hydrogen container; the cold end piston divides the cold end cylinder body into a cold end cylinder body upper cavity and a cold end cylinder body lower cavity, the cold end cylinder body upper cavity is communicated with the isolation valve through an upper cavity suction pipe, the cold end cylinder body upper cavity is also connected with the liquid hydrogen outlet pipe through an upper cavity discharge pipe, an upper cavity inlet one-way valve is arranged on the upper cavity suction pipe, and an upper cavity outlet one-way valve is arranged on the cold end cylinder body top connected with the upper cavity discharge pipe or the upper cavity discharge pipe; the cold end cylinder body lower cavity is communicated with the isolating valve through a lower cavity inlet one-way valve arranged at the bottom of the cold end cylinder body, and a lower cavity outlet one-way valve used for communicating the cold end cylinder body lower cavity with a liquid hydrogen outlet pipe is arranged at the bottom of the cold end cylinder body or on the wall of the cold end cylinder body; and a support rod cold end sealing ring is arranged at the contact position of the support rod and the top of the cold end cylinder body.

As a first preferable scheme of the power part, the power part comprises a normal temperature component and a high-pressure fluid power source; the normal temperature assembly comprises a normal temperature piston arranged in a normal temperature cylinder body, wherein a normal temperature piston sealing ring used for filling a gap between the normal temperature piston and the inner wall of the cylinder body is sleeved on the normal temperature piston; the high-pressure fluid power source is respectively communicated with cylinder cavities at the upper side and the lower side of the normal-temperature piston through two pipelines; the working states of the cylinder cavities on the upper side and the lower side of the normal-temperature piston are different during working, namely when fluid enters the cylinder cavity on one side of the normal-temperature piston, the fluid is discharged from the cylinder cavity on the other side of the normal-temperature piston; the upper end of the supporting rod penetrates through the bottom of the normal-temperature cylinder body to be connected with the normal-temperature piston, and the lower end of the supporting rod penetrates through the top of the cold-end cylinder body to be connected with the cold-end piston.

Preferably, the normal temperature assembly comprises a normal temperature cylinder body with an opening at the upper part and an opening at the lower part, a sealed top cover is arranged at the opening at the upper part of the normal temperature cylinder body, and a sealed bottom cover is arranged at the opening at the lower part of the normal temperature cylinder body; the top cover is provided with a top pipeline communicated with a cylinder cavity above the normal-temperature piston, the bottom cover is provided with a bottom pipeline communicated with the cylinder cavity below the normal-temperature piston, and the top pipeline and the bottom pipeline are two pipelines communicated with the high-pressure fluid power source; the upper end of the supporting rod penetrates through the bottom cover to be connected with the normal-temperature piston, and a supporting rod normal-temperature sealing ring is arranged at the contact position of the supporting rod and the bottom cover.

Preferably, the top pipeline and the bottom pipeline are both connected with the high-pressure fluid power source through the reversing valve, the high-pressure fluid power source provides high-pressure fluid power for only one of the top pipeline and the bottom pipeline through the reversing valve at the same time, and the reversing valve is a three-position four-way reversing valve or a three-position five-way reversing valve.

Further preferably, only the top cover of the liquid hydrogen pump extends out of the outer side of the isolation part; the bottom pipeline penetrates through the top cover to enter the isolation part and then is communicated with a cylinder cavity below the normal-temperature piston through the bottom cover; and a liquid hydrogen outlet pipe for discharging the liquid hydrogen passes through the top cover to convey the liquid hydrogen to the outside.

Further preferably, the cold end is a cold end assembly; the cold end assembly comprises a cold end cylinder body with an opening at the lower part, a cold end bottom cover for sealing is fixedly arranged at the opening at the lower part of the cold end cylinder body, and a channel communicated with a valve core of the isolating valve is formed in the cold end bottom cover;

preferably, the cold end assembly and the normal temperature assembly are fixedly connected through a support cylinder, and the support rod penetrates through the support cylinder; the liquid hydrogen outlet pipe spirally rises around the branch cylinder.

As a preferable scheme of the invention, the isolation part is an isolation assembly, a groove matched with the shape of the isolation assembly is formed on the liquid hydrogen container, and the isolation assembly is arranged in the groove; the isolation assembly comprises an isolation cylinder, and a pump body of the reciprocating submerged type liquid hydrogen pump is arranged in the isolation cylinder; the isolation assembly further comprises an isolation valve installed at the bottom of the isolation cylinder, and the isolation valve is a connection medium between liquid hydrogen in the liquid hydrogen container and the cold end.

Preferably, the isolation cylinder is a double-layer sleeve with an opening at the upper part and the lower part, and the double-layer sleeve divides the isolation cylinder into a cylinder cavity space and a cavity clamping space between the sleeves; a top mounting flange is arranged at the top of the isolation cylinder, a bottom mounting flange is arranged at the bottom of the isolation cylinder, the bottom mounting flange and the liquid hydrogen container form movable contact and are in sealing connection, and the top mounting flange is fixedly and hermetically connected with a top cover on the pump body; the top mounting flange is provided with a through hole which is convenient for pumping the space of the inner cylinder cavity of the isolation cylinder into a vacuum state; the isolating cylinder body is provided with a vacuumizing interface which is convenient for vacuumizing the space of the clamping cavity in the isolating cylinder, the bottom mounting flange is hollow, and the bottom mounting flange is provided with a through hole which is communicated with the inner cavity of the bottom mounting flange and the space of the clamping cavity in the isolating cylinder; and a pressure sensor or a vacuum pressure gauge for monitoring the pressure of the cylinder cavity is also arranged on the mounting flange at the top.

Preferably, the isolation valve comprises a valve core, a valve body with an opening at the upper part and a valve cover, wherein the valve cover is fixed on the bottom mounting flange and is provided with a flow port for liquid hydrogen to flow; the valve body is fixedly arranged at the bottom of the valve cover and is positioned below the circulation port, the valve body extends downwards into the liquid hydrogen container, and at least one drainage port for liquid hydrogen to flow into the valve body is formed in the valve body; a cylindrical cold end bottom cover convex part is arranged on the lower side of the cold end bottom cover, a cold end bottom cover liquid inlet hole is formed in the cold end bottom cover convex part, and the outer diameter of the cold end bottom cover convex part is matched with the inner diameter of a flow hole in the valve cover;

the valve core and the valve cover are matched to realize the following two working states: when the valve core is abutted against the valve cover, the flow port is blocked, and the liquid hydrogen in the liquid hydrogen container cannot be conveyed outwards; or the convex part of the cold end bottom cover on the lower side of the cold end bottom cover is inserted into the circulation port on the valve cover, and the convex part of the cold end bottom cover is pressed on the top of the valve core, so that when the valve core is not pressed against the valve cover, the drainage port, the liquid hydrogen inlet hole of the cold end bottom cover and the circulation port are communicated with each other, and liquid hydrogen in the liquid hydrogen container can be normally conveyed outwards; the case is the syllogic ladder column of upper coarse thin lower, the valve body bottom is worn to locate to the mobilizable lower half section of case, be equipped with the compression spring that the cover was established on the valve core lower half section in the valve body, compression spring keeps away from the one end butt of valve body to the first half section of case, when compression spring was in natural state, compression spring oppresses the first half of case and makes its shutoff stop up the circulation mouth on the valve gap.

Compared with the prior art, the invention has the beneficial effects that:

1. when the reciprocating pump device is used, a reciprocating pump structure that a traditional motor directly drives a cold end (hydraulic end) piston (plunger) to reciprocate through a crank connecting rod mechanism is cancelled, the reciprocating pump device is changed into a submerged liquid hydrogen reciprocating pump device that power is transmitted remotely through high-pressure fluid, namely, a high-pressure fluid power source is used for providing power for a normal-temperature assembly, the high-pressure fluid power source drives the normal-temperature piston to reciprocate up and down and simultaneously drives the cold end piston to reciprocate, compared with the electric structure of the traditional crank connecting rod, the running process is safer and quicker, the scheme completely isolates the power source from an ultralow-temperature (-253 ℃) liquid hydrogen medium and a flammable and explosive hydrogen medium environment, the technical problems of the motor in the ultralow-temperature environment and the motor power mechanism in the flammable and explosive environment are effectively solved, and the system is safe and reliable and is easy to implement in engineering.

2. The liquid hydrogen pump of the invention generates pressure difference in the reciprocating motion process, so that the cold end assembly sucks liquid hydrogen from the inlet one-way valve and discharges the liquid hydrogen from the outlet one-way valve to finish the transportation of the liquid hydrogen. In conventional designs, the output stage of the reciprocating pump is the scheduling stage of the piston or plunger, i.e. the output of the reciprocating pump in the prior art is single-acting.

Different from the conventional design, the cold end piston divides the cold end cylinder body into a cold end cylinder body upper cavity and a cold end cylinder body lower cavity, so the invention develops a new method, so that the cold end cylinder body upper cavity is communicated with the isolation valve through an upper cavity suction pipe, the cold end cylinder body upper cavity is also connected with the liquid hydrogen outlet pipe through an upper cavity discharge pipe, the invention is provided with an upper cavity inlet one-way valve on the upper cavity suction pipe, and an upper cavity outlet one-way valve is arranged on the top of the cold end cylinder body connected with the upper cavity discharge pipe or on the upper cavity discharge pipe; therefore, the upper cavity of the cold end cylinder body also has the function of conveying liquid hydrogen, namely, due to the arrangement of the upper cavity inlet one-way valve and the upper cavity outlet one-way valve, when the cold end piston moves upwards, the upper cavity of the cold end cylinder body also has the function of conveying liquid hydrogen.

At the same time, the lower cavity of the cold-end cylinder body is still connected with the isolation valve through a lower cavity inlet one-way valve arranged at the bottom of the cold-end cylinder body, and a lower cavity outlet one-way valve used for communicating the lower cavity of the cold-end cylinder body with a liquid hydrogen outlet pipe is arranged at the bottom of the cold-end cylinder body or on the wall of the cold-end cylinder body; and a support rod cold end sealing ring is arranged at the contact position of the support rod and the top of the cold end cylinder body.

The structure of the invention enables the upper cavity of the cold end cylinder body to complete liquid hydrogen suction and discharge work through the upper cavity outlet one-way valve and the upper cavity inlet one-way valve, and the upper cavity of the cold end cylinder body to complete liquid hydrogen suction and discharge work through the lower cavity inlet one-way valve and the lower cavity outlet one-way valve, thereby enabling the liquid hydrogen pump to be changed from a single-acting type (namely, liquid hydrogen is discharged only in the scheduling stage) to a double-acting type (namely, liquid hydrogen is discharged in both the process stage and the scheduling stage) in the prior art.

In addition, because epicoele entry check valve and cavity entry check valve down all link to each other with the isolating valve, consequently after cutting off high-pressure fluid power supply, although the liquid hydrogen pump stops the transport to liquid hydrogen, but at this moment at least one space in the space above or the space below of cold junction piston still remains liquid hydrogen, so when restarting the liquid hydrogen pump next time, need not the precooling and can directly work, improved work efficiency effectively.

3. When the high-pressure fluid cylinder is used, the reversing valve is arranged between the high-pressure fluid power source and the top pipeline and the bottom pipeline, so that the high-pressure fluid power source can provide high-pressure fluid power for only one of the top pipeline and the bottom pipeline through the reversing valve at the same time, power conflict between the two pipelines is prevented, and the liquid discharge pipeline on the reversing valve can effectively discharge the fluid discharged from the normal-temperature cylinder body in the working process; the top pipeline and the bottom pipeline can be air inlet pipelines or liquid inlet pipelines, and various pipeline choices are provided for different power sources which can be connected.

4. When the invention is used, the liquid hydrogen pump is arranged in the isolation component. During operation (the liquid hydrogen pump is in the state that the installation finishes this moment), cold junction bottom convex part of the cold junction bottom downside of cold junction cylinder body inserts in the circulation opening of isolating valve gap, and cold junction bottom convex part pass through the circulation opening and press the top of isolating valve case makes keep having certain clearance between case and the valve gap, this moment drainage mouth, cold junction bottom on the valve body advance liquid hydrogen hole and the circulation opening of valve gap communicate each other, and liquid hydrogen accessible drainage mouth, cold junction bottom in the liquid hydrogen container advance liquid hydrogen hole and circulation opening and normally outwards carry.

Because the liquid hydrogen in the liquid hydrogen container reaches the circulation opening through the drainage opening and the liquid hydrogen inlet hole of the cold end bottom cover, when the cold end piston moves downwards under the action of the supporting rod, the volume of the upper cavity of the cold end cylinder body is increased, the pressure is reduced, and at the moment, the liquid hydrogen enters the upper cavity of the cold end cylinder body through the drainage opening and the upper cavity inlet one-way valve on the upper cavity suction pipe and waits for being discharged; meanwhile, the volume of the lower cavity of the cold end cylinder body is reduced, the pressure is increased, and the liquid hydrogen in the lower cavity of the cold end cylinder body enters the lower cavity discharge pipe through the lower cavity outlet one-way valve and is finally discharged through the liquid hydrogen container outlet pipe. On the contrary, when the cold end piston moves upwards under the action of the support rod, the volume of the upper cavity of the cold end cylinder body is reduced, the pressure is increased, and at the moment, the liquid hydrogen enters the upper cavity discharge pipe through an upper cavity outlet one-way valve on the upper cavity discharge pipe and is finally discharged through an outlet pipe of the liquid hydrogen container; meanwhile, the volume of the lower cavity of the cold-end cylinder body is increased, the pressure is reduced, and the liquid hydrogen enters the lower cavity of the cold-end cylinder body through the flow opening and the lower cavity inlet one-way valve to wait for discharge.

Naturally, under normal conditions, also when the liquid hydrogen pump overhauls, the cold junction cylinder body was taken out this moment, and the cold junction bottom cover convex part of the cold junction bottom cover downside of cold junction cylinder body also no longer inserted in the circulation mouth of valve gap, cold junction bottom cover convex part is also pressing at this moment the top of case, and compression spring in the isolation valve is in upwards top and leans on and makes the state of the circulation mouth of valve gap shutoff valve core, and whole isolation valve is in closed condition promptly, ensures the closure of liquid hydrogen container.

5. When the liquid hydrogen pump is used, the liquid hydrogen pump is arranged in the isolation assembly, the cavity clamping spaces of the bottom mounting flange and the isolation cylinder are both vacuumized through the vacuumizing interface, and the cavity space of the inner cylinder of the isolation cylinder is also vacuumized through the through hole formed in the top mounting flange, so that the heat transfer in the isolation assembly is reduced, and meanwhile, only the top cover of the liquid hydrogen pump body is positioned on the outer side of the isolation assembly, the heat transfer area is small, and the absorption of external heat is extremely limited, so that the BOG loss in the working process can be effectively reduced; a position reserved on the top mounting flange can be additionally provided with a pressure sensor, real-time pressure monitoring is carried out on the space outside the internal pump body of the isolation cylinder, when liquid hydrogen leaks, pressure rise can be timely found, danger is avoided, and meanwhile the use condition of the sealing ring can be known according to the change of pressure so as to be convenient for timely replacement; meanwhile, the hole formed in the mounting flange at the top can release trace hydrogen leaked when the liquid hydrogen pump is dismounted in the isolation assembly to the outside safely, and nitrogen purging can be carried out to the inside to ensure that no oxygen remains in the inside.

6. When the liquid hydrogen pump is used, the liquid hydrogen pump is high in temperature during normal-temperature production and low in temperature during working, so that the temperature difference is overlarge, the liquid hydrogen outlet pipe is arranged to spirally rise around the support cylinder after passing through the outlet one-way valve, the situation that the liquid hydrogen outlet pipe is contracted and broken in an excessively low-temperature state is avoided, and elastic compensation is effectively performed by arranging the liquid hydrogen pump in a spiral shape.

Drawings

Fig. 1 is a schematic view of the installation of a double-acting reciprocating submerged liquid hydrogen pump in a liquid hydrogen container. The power section in fig. 1 includes a cool component 2 and a power source station 4.

Fig. 2 is a schematic structural view of the double-acting reciprocating submerged liquid hydrogen pump of the present invention.

Fig. 3 is a partially enlarged view of fig. 2.

Fig. 4 is a schematic structural diagram of an isolation valve in a double-acting reciprocating submerged liquid hydrogen pump.

In the figure:

1. a cold end assembly; 2. a normal temperature component; 3. an isolation component; 4. a power source station; 5. a power assembly; 6. A liquid hydrogen container; 7. a pump body 8, a liquid hydrogen container outlet pipe;

101. an upper cavity outlet one-way valve; 102. an upper chamber inlet check valve; 103. a sealing ring at the cold end of the supporting rod; 104. A cold end piston; 105. a cold end piston seal ring; 106. a cold end cylinder body; 107. a lower cavity outlet one-way valve; 108. a cold end bottom cover; 1081. a cold end bottom cover convex portion; 1082. a liquid inlet hydrogen hole is formed in the bottom cover of the cold end; 109. a lower cavity inlet check valve;

201. supporting a cylinder; 202. a strut; 203. a bottom cover; 204. a normal-temperature sealing ring of the supporting rod; 205. a normal-temperature cylinder body; 206. a normal temperature piston seal ring; 207. a piston at normal temperature; 208. a top cover; 209. a top pipeline; 210. A bottom pipeline;

301. installing a flange at the top; 302. an isolation cylinder; 303. a bottom mounting flange; 304. an isolation valve; 3041. A valve body; 30411. a drainage opening; 3042. a compression spring; 3043. a valve cover; 3044. a valve core;

401. a high pressure fluid power source; 402. a reversing valve;

501. a metering pump; 502. a drive line; 503. a safety relief valve; 504. a pressure stabilizing container; 505. a pressure stabilizing pipeline;

81. an upper chamber discharge pipe; 82. a lower cavity discharge pipe; 83. upper cavity suction pipe

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, in an embodiment of the present invention, a double-acting reciprocating submerged liquid hydrogen pump includes the following components:

the reciprocating submerged type liquid hydrogen pump comprises the following components:

a partition connected to the liquid hydrogen container 6, the partition completely separating the pump main body 7 from the liquid hydrogen container 6, the pump main body 7 being installed inside the partition;

a pump body cold end for receiving liquid hydrogen from the liquid hydrogen container 6 and discharging the liquid hydrogen to a liquid hydrogen outlet pipe 8;

the power part is connected with the cold end part and drives the cold end part to reciprocate by adopting high-pressure fluid in the power source station 4 so as to realize the discharge of liquid hydrogen;

as shown in fig. 2, the cold end includes a cold end cylinder 106, a cold end piston 104 connected to the power unit through a strut 202 is disposed in the cold end cylinder 106, and a cold end piston sealing ring 105 for filling a gap between the cold end piston 104 and an inner wall of the cylinder is sleeved on the periphery of the cold end piston 104; an isolating valve 304 for communicating or separating a cold end cylinder lower cavity on the lower side of the cold end piston 104 with the liquid hydrogen container is arranged on the lower side of the cold end cylinder 106; the cold end piston 104 divides the cold end cylinder 106 into a cold end cylinder upper chamber and a cold end cylinder lower chamber, the cold end cylinder upper chamber is connected with the isolating valve 304 through an upper chamber suction pipe 83, the cold end cylinder upper chamber is also connected with the liquid hydrogen outlet pipe 8 through an upper chamber discharge pipe 81, an upper chamber inlet one-way valve 102 is arranged on the upper chamber suction pipe 83, and an upper chamber outlet one-way valve 101 is arranged on the cold end cylinder top connected with the upper chamber discharge pipe 81 or the upper chamber discharge pipe 81; the cold end cylinder lower cavity is connected with the isolation valve 304 through a lower cavity inlet one-way valve 109 arranged at the bottom of the cold end cylinder 106, and a lower cavity outlet one-way valve 107 used for communicating the cold end cylinder lower cavity with a liquid hydrogen outlet pipe is arranged at the bottom of the cold end cylinder or on the wall of the cold end cylinder; and a support rod cold end sealing ring 103 is arranged at the contact part of the support rod 202 and the top of the cold end cylinder body 106.

The upper chamber discharge pipe 81 and the upper chamber suction pipe 83 may be separately provided, or may be connected to each other, that is, as shown in fig. 2 and 4, the upper chamber discharge pipe 81 where the upper chamber outlet check valve 101 is located and the upper chamber suction pipe 83 where the upper chamber inlet check valve 102 is located are communicated with the cold end cylinder upper chamber above the cold end piston through a three-way pipe.

As shown in fig. 3, the upper chamber suction line 83 is formed in the cold end bottom cover 108 and is connected in parallel to the lower chamber inlet check valve 109.

As shown in fig. 2, the upper chamber discharge pipe 81 and the lower chamber discharge pipe 82 with the lower chamber outlet check valve 107 are finally combined into one output pipeline, i.e. the liquid hydrogen container outlet pipe 8.

The structure of the power unit will be described in detail with reference to the accompanying drawings.

As shown in fig. 1 and 2, the power part comprises a normal temperature assembly 2 and a high-pressure fluid power source 401; the normal temperature assembly 2 comprises a normal temperature piston 207 arranged in a normal temperature cylinder 205, wherein a normal temperature piston sealing ring 206 used for filling a gap between the normal temperature piston 207 and the inner wall of the cylinder is sleeved on the normal temperature piston 207; the high-pressure fluid power source 401 is respectively communicated with cylinder cavities at the upper side and the lower side of the normal-temperature piston 207 through two pipelines; the cylinder cavities on the upper and lower sides of the normal temperature piston 207 are different in working state when in working, that is, when the cylinder cavity on one side of the normal temperature piston 207 enters fluid, the cylinder cavity on the other side of the normal temperature piston 207 discharges the fluid; the upper end of the strut 202 passes through the bottom of the normal temperature cylinder 205 to be connected with the normal temperature piston 207, and the lower end of the strut 202 passes downward through the top of the cold end cylinder 106 to be connected with the cold end piston 104.

The normal temperature component 2 comprises a normal temperature cylinder 205 with an opening at the upper part and the lower part, a sealed top cover 208 is arranged at the opening at the upper part of the normal temperature cylinder 205, and a sealed bottom cover 203 is arranged at the opening at the lower part; a top pipeline 209 communicated with a cylinder cavity above the normal-temperature piston 207 is arranged on the top cover 208, a bottom pipeline 210 communicated with a cylinder cavity below the normal-temperature piston 207 is arranged on the bottom cover 203, and the top pipeline 209 and the bottom pipeline 210 are two pipelines communicated with the high-pressure fluid power source 401; the upper end of the support rod 202 penetrates through the bottom cover 203 to be connected with the normal temperature piston 207, and a support rod normal temperature sealing ring 204 is arranged at the contact position of the support rod 202 and the bottom cover 203.

The high-pressure fluid power source can be inert gases such as nitrogen and can also be liquid such as high-pressure hydraulic oil.

The top pipeline 209 and the bottom pipeline 210 are both connected with a high-pressure fluid power source 401 through a reversing valve 402, the high-pressure fluid power source 401 only provides high-pressure fluid power for one of the top pipeline 209 and the bottom pipeline 210 through the reversing valve 402 at the same time, and the reversing valve 402 is a three-position four-way reversing valve or a three-position five-way reversing valve.

The liquid hydrogen pump only has a top cover 208 extending out of the isolating part; the bottom pipeline 210 penetrates through the top cover 208 to enter the isolation part, and then is communicated with a cylinder cavity below the normal-temperature piston 207 through the bottom cover 203; a liquid hydrogen outlet pipe for discharging liquid hydrogen passes through the top cover 208 to deliver the liquid hydrogen to the outside.

The cold end part is a cold end component 1; the cold end assembly 1 comprises a cold end cylinder 106 with an opening at the lower part, a cold end bottom cover 108 for sealing is fixedly arranged at the opening at the lower part of the cold end cylinder 106, and a channel communicated with the isolating valve 304 is formed in the cold end bottom cover 108;

the cold end component 1 and the normal temperature component 2 are fixedly connected through a support cylinder 201, and the support rod 202 penetrates through the support cylinder 201; the liquid hydrogen outlet pipe spirals up around the branch 201.

Since the separator is an important and critical component of the present invention, the structure and function of the separator will be described separately with reference to the accompanying drawings.

As shown in fig. 2 and 4, the isolating part is an isolating assembly 3, a groove matched with the shape of the isolating assembly 3 is formed in the liquid hydrogen container 6, and the isolating assembly 3 is installed in the groove; the isolation assembly 3 comprises an isolation cylinder 302, and a pump body of the reciprocating submerged liquid type liquid hydrogen pump is arranged in the isolation cylinder 302; the isolation assembly 3 further comprises an isolation valve 304 mounted at the bottom of the isolation cylinder 302, wherein the isolation valve 304 is a connection medium between the liquid hydrogen in the liquid hydrogen container 6 and the cold end.

The isolation cylinder 302 is a double-layer sleeve with an upper opening and a lower opening, and the double-layer sleeve divides the isolation cylinder 302 into a cylinder cavity space and a cavity clamping space between the sleeves; a top mounting flange 301 is arranged at the top of the isolation cylinder 302, a bottom mounting flange 303 is arranged at the bottom of the isolation cylinder 302, the bottom mounting flange 303 and the liquid hydrogen container 6 are in movable contact and are in sealing connection, and the top mounting flange 301 is fixedly and hermetically connected with a top cover 208 on the pump body; the top mounting flange 301 is provided with a through hole which is convenient for pumping the space of the inner cylinder cavity of the isolation cylinder 302 into a vacuum state; the body of the isolation cylinder 302 is provided with a vacuumizing interface which is convenient for vacuumizing the cavity space in the isolation cylinder 302, the bottom mounting flange 303 is hollow, and the bottom mounting flange 303 is provided with a through hole which is communicated with the inner cavity of the bottom mounting flange 303 and the cavity space in the isolation cylinder 302; and a pressure sensor or a vacuum pressure gauge for monitoring the pressure of the cylinder cavity is also arranged on the top mounting flange 301.

The top mounting flange 301 and the bottom mounting flange 303 can be fixed with the isolation cylinder 302 in a welding mode.

When the liquid hydrogen container is installed, the top installation flange 301 can be fixed with an installation flange arranged on the liquid hydrogen container 6 through bolts, the contact surface is sealed by a sealing ring, and then the bottom installation flange 303 and the liquid hydrogen container 6 are compressed and sealed through a sealing gasket; or only fixing the bottom mounting flange 303 and the mounting flange on the liquid hydrogen container 6 by bolts, sealing the contact surface by a sealing ring, and then pressing and sealing the top mounting flange 301 and the liquid hydrogen container 6 by a sealing gasket; the top mounting flange 301 and the bottom mounting flange 303 can be fixedly connected with mounting flanges carried by the liquid hydrogen container 6 through bolts, and the contact surfaces are sealed by sealing rings.

As shown in fig. 2, the isolation cylinder 302 is a cylindrical installation space provided on the liquid hydrogen container 6, and a top installation flange 301 and a bottom installation flange 303 are used for fixing the isolation cylinder 302. The isolation cylinder 302 is directly installed on the liquid hydrogen container 6, and the pump body 7 is directly installed in the isolation cylinder 302, so that the main functions of the isolation cylinder 302 are heat insulation and communication, wherein the heat insulation is realized through the cylinder body structure of the isolation cylinder 302, and the communication is that the pump body 7 arranged in the isolation cylinder 302 is communicated with the liquid hydrogen container 6 through the isolation valve 304 arranged at the bottom of the isolation cylinder 302.

As shown in fig. 4, the isolation valve 304 includes a valve core 3044, a valve body 3041 with an open top, and a valve cover 3043, where the valve cover 3043 is fixed on the bottom mounting flange 303, and the valve cover 3043 is provided with a flow port through which hydrogen flows; the valve body 3041 is fixedly arranged at the bottom of the valve cover 3043 and below the flow port, the valve body 3041 extends downwards into the liquid hydrogen container, and the valve body 3041 is provided with at least one flow guide port 30411 for allowing liquid hydrogen to flow into the valve body 3041; a cylindrical cold end bottom cover protrusion 1081 is arranged on the lower side of the cold end bottom cover 108, a cold end bottom cover liquid inlet hydrogen hole 1082 is formed in the cold end bottom cover protrusion 1081, and the outer diameter of the cold end bottom cover protrusion 1081 is matched with the inner diameter of the flow port in the valve cover 3043.

The valve core 3044 and the valve cover 3043 are matched to realize the following two working states: when the valve core 3044 abuts against the valve cover 3043, the flow port is blocked, and the liquid hydrogen in the liquid hydrogen container cannot be conveyed outwards; or, the cold end bottom cover protrusion 1081 on the lower side of the cold end bottom cover 108 is inserted into the flow port on the valve cover 3043, and the cold end bottom cover protrusion 1081 is pressed against the top of the valve core 3044, so that when the valve core 3044 is not abutted to the valve cover 3043, the drainage port 30411, the cold end bottom cover liquid hydrogen inlet hole 1082 and the flow port are communicated with each other, and the liquid hydrogen in the liquid hydrogen container can be normally conveyed outwards; the valve core 3044 is a two-section stepped column with a thick upper part and a thin lower part, the thin lower half section of the valve core 3044 movably penetrates the bottom of the valve body 3041, a compression spring 3042 sleeved on the lower half section of the valve core is arranged in the valve body 3041, one end of the compression spring 3042 far away from the valve body 3041 is abutted to the upper half section of the valve core 3044, and when the compression spring 3042 is in a natural state, the compression spring 3042 presses the upper half section of the valve core 3044 to seal the flow opening on the valve cover 3043.

The valve cover 3043 and the bottom mounting flange 303 can be selectively secured by bolts, and the valve body 3041 and the valve cover 3043 can also be selectively secured by bolts, wherein the compression spring 3042 is preferably disposed on the valve core 3044.

The operation of the present invention will be described in detail with reference to the accompanying drawings.

As shown in fig. 1 and 2, the working principle of the present invention is: when the high-pressure fluid power source is used, high-pressure fluid power is respectively injected into the top pipeline 209 and the bottom pipeline 210 in a reciprocating mode through the reversing valve 402, the working states of cylinder cavities on the upper side and the lower side of the normal-temperature piston 207 are different, when the high-pressure fluid power is continuously injected into the top pipeline 209, the pressure intensity of the cylinder cavity on the upper side of the normal-temperature piston 207 is increased, the normal-temperature piston 207 moves downwards in order to balance the pressure intensity in the normal-temperature cylinder 205, meanwhile, the fluid in the cylinder cavity on the lower side of the normal-temperature piston 207 is discharged, the fluid can be discharged from a pipeline additionally arranged on the normal-temperature cylinder 205, and the fluid can also be discharged from a liquid discharge pipeline arranged on the three-position four-way reversing valve or the three-position five-way reversing valve; after the normal temperature piston 207 moves downwards to a certain degree, the reversing valve 402 stops injecting high-pressure fluid power into the top pipeline 209 again, the high-pressure fluid power is injected into the bottom pipeline 210 instead, the normal temperature piston 207 moves upwards again until the pressure intensity of the cylinder cavity on the lower side of the normal temperature piston 207 is larger than the pressure intensity of the cylinder cavity on the lower side, meanwhile, the fluid in the cylinder cavity on the upper side of the normal temperature piston 207 is discharged, and the steps are carried out in a reciprocating mode, so that the normal temperature piston 207 moves up and down in a reciprocating mode.

The normal temperature piston 207 reciprocates up and down, and simultaneously drives the cold end piston 104 to synchronously reciprocate up and down through the strut 202.

When the invention is used, the pump main body 7 of the liquid hydrogen pump is arranged in the isolation component 3. During operation (at this time, the pump main body 7 of the liquid hydrogen pump is in a mounted state), the cold-end bottom cover convex portion 1081 on the lower side of the cold-end bottom cover 108 of the cold-end cylinder 106 is inserted into the flow port of the valve cover 3043, and the cold-end bottom cover convex portion 1081 penetrates through the flow port and is pressed against the top of the valve core 3044, so that a certain gap is maintained between the valve core 3044 and the valve cover 3043, at this time, the drainage port 30411 on the valve body 3041, the cold-end bottom cover liquid hydrogen inlet hole 1082 and the flow port of the valve cover 3043 are communicated with each other, and liquid hydrogen in the liquid hydrogen container 6 can be normally conveyed outwards through the drainage port 30411, the cold-end bottom cover liquid hydrogen inlet hole 1082 and the flow port.

Since the liquid hydrogen in the liquid hydrogen container 6 reaches the flow port through the drainage port 30411 and the liquid hydrogen inlet hole 1082 of the cold end bottom cover, when the cold end piston 104 moves down under the action of the strut 202, the volume of the upper cavity of the cold end cylinder body increases, the pressure decreases, and at this time, the liquid hydrogen enters the upper cavity of the cold end cylinder body through the flow port and the upper cavity inlet check valve 102 on the upper cavity suction pipe 83 to wait for discharge; meanwhile, the volume of the lower cavity of the cold-end cylinder body is reduced, the pressure is increased, and the liquid hydrogen in the lower cavity of the cold-end cylinder body enters the lower cavity discharge pipe 82 through the lower cavity outlet one-way valve 107 and is finally discharged through the liquid hydrogen container outlet pipe 8. Conversely, when the cold-end piston 104 moves upwards under the action of the strut 202, the volume of the upper cavity of the cold-end cylinder body is reduced, the pressure is increased, and at the moment, the liquid hydrogen enters the upper cavity discharge pipe 81 through the upper cavity outlet one-way valve 101 on the upper cavity discharge pipe 81 and is finally discharged through the liquid hydrogen container outlet pipe 8; meanwhile, the volume of the lower cavity of the cold-end cylinder body is increased, the pressure is reduced, and the liquid hydrogen enters the lower cavity of the cold-end cylinder body through the flow opening and the lower cavity inlet one-way valve 109 to wait for discharge.

Of course, when the pump main body 7 of the liquid hydrogen pump is overhauled, the cold-end cylinder 106 is drawn out, the cold-end bottom cover projection 1081 on the lower side of the cold-end bottom cover 108 of the cold-end cylinder 106 is no longer inserted into the flow port of the valve cover 3043, the cold-end bottom cover projection 1081 is no longer pressed against the top of the valve core 3044, and the compression spring 3042 in the isolation valve 304 is in a state of being abutted upward so that the valve core 3044 blocks the flow port of the valve cover 3043, that is, the entire isolation valve 304 is in a closed state, thereby ensuring the sealing performance of the liquid hydrogen container 6.

During operation, liquid hydrogen in the liquid hydrogen container 6 can be normally conveyed outwards through the drainage port 30411, the liquid hydrogen inlet hole 1082 of the cold end bottom cover and the circulation port, so that after the high-pressure fluid power source is cut off, although the liquid hydrogen pump stops conveying the liquid hydrogen, liquid hydrogen still remains in the upper space and the lower space of the cold end piston 104 at the moment, and therefore when the liquid hydrogen pump is restarted next time, direct operation can be achieved without precooling, and the working efficiency is effectively improved.

As shown in fig. 2, the liquid hydrogen pump of the present invention is installed in the isolation assembly 3, the cavity-clamping spaces of the bottom mounting flange 303 and the isolation cylinder 302 are both evacuated through the evacuation interface, and the cavity space of the inner cylinder of the isolation cylinder 302 is also evacuated through the through hole formed in the top mounting flange 301, so that the heat transfer in the isolation assembly 3 is reduced, and at the same time, the liquid hydrogen pump main body 7 only has the top cover 208 located outside the isolation assembly 3, the heat transfer area is small, and the absorption of external heat is extremely limited, so that the BOG loss in the working process can be effectively reduced; a position reserved on the top mounting flange 301 can be additionally provided with a pressure sensor to monitor the pressure in real time in the space outside the internal pump body of the isolation cylinder 302, if liquid hydrogen leaks, the pressure rise can be timely found to avoid danger, and meanwhile, the use condition of the sealing ring can be known according to the pressure change so as to be convenient for timely replacement; meanwhile, the hole formed in the top mounting flange 301 can release trace hydrogen leaked during the disassembly and assembly of the liquid hydrogen pump in the isolation assembly 3 to the outside safely, and nitrogen purging can be performed to the inside to ensure that no oxygen remains inside.

Because the liquid hydrogen pump temperature is higher when normal atmospheric temperature production, and the temperature is lower in the course of the work, leads to the difference in temperature too big, consequently sets up liquid hydrogen outlet pipe 8 to encircle a 201 spiral rising behind the outlet check valve 102, avoids liquid hydrogen outlet pipe 8 to take place the shrink fracture condition under the low temperature state, establishes to the heliciform and has effectively carried out the elasticity compensation.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims

1. A double-acting type reciprocating submerged liquid hydrogen pump is characterized by comprising the following components:

the cold end part of the pump main body is used for receiving the liquid hydrogen from the liquid hydrogen container and discharging the liquid hydrogen to the liquid hydrogen outlet pipe;

the power part is connected with the cold end part and drives the cold end part to reciprocate by adopting high-pressure fluid in the power source station (4) so as to realize the discharge of liquid hydrogen;

the cold end comprises a cold end cylinder (106), a cold end piston (104) connected with the power part through a support rod (202) is arranged in the cold end cylinder (106), and a cold end piston sealing ring (105) used for filling a gap between the cold end piston (104) and the inner wall of the cylinder is sleeved on the periphery of the cold end piston (104); an isolation valve (304) which is used for communicating or separating a lower cavity of the cold end cylinder body on the lower side of the cold end piston (104) from the liquid hydrogen container is arranged on the lower side of the cold end cylinder body (106); the cold end piston (104) divides the cold end cylinder body (106) into a cold end cylinder body upper cavity and a cold end cylinder body lower cavity, the cold end cylinder body upper cavity is communicated with the isolating valve (304) through an upper cavity suction pipe (83), the cold end cylinder body upper cavity is also connected with the liquid hydrogen outlet pipe (8) through an upper cavity discharge pipe (81), an upper cavity inlet one-way valve (102) is arranged on the upper cavity suction pipe (83), and an upper cavity outlet one-way valve (101) is arranged on the cold end cylinder body top connected with the upper cavity discharge pipe (81) or the upper cavity discharge pipe (81); the cold end cylinder lower cavity is communicated with the isolating valve (304) through a lower cavity inlet one-way valve (109) arranged at the bottom of the cold end cylinder (106), and a lower cavity outlet one-way valve (107) used for communicating the cold end cylinder lower cavity with a liquid hydrogen outlet pipe is arranged at the bottom of the cold end cylinder or on the wall of the cold end cylinder; a cold end sealing ring (103) of the strut is arranged at the contact part of the strut (202) and the top of the cold end cylinder body (106);

the isolating part is an isolating assembly (3), a groove matched with the shape of the isolating assembly (3) is formed in the liquid hydrogen container, and the isolating assembly (3) is arranged in the groove; the isolation assembly (3) comprises an isolation cylinder (302), and a pump body of the reciprocating submerged type liquid hydrogen pump is arranged in the isolation cylinder (302); the isolation assembly (3) further comprises an isolation valve (304) installed at the bottom of the isolation cylinder (302), and the isolation valve (304) is a connecting medium between the liquid hydrogen in the liquid hydrogen container and the cold end;

the isolation cylinder (302) is a double-layer sleeve with an upper opening and a lower opening, and the double-layer sleeve divides the isolation cylinder (302) into a cylinder cavity space and a cavity clamping space between the sleeves; a top mounting flange (301) is arranged at the top of the isolation cylinder (302), a bottom mounting flange (303) is arranged at the bottom of the isolation cylinder (302), the bottom mounting flange (303) and the liquid hydrogen container form movable contact and are in sealing connection, and the top mounting flange (301) is fixedly and hermetically connected with a top cover (208) on the pump main body; the top mounting flange (301) is provided with a through hole which is convenient for pumping the space of the inner cylinder cavity of the isolation cylinder (302) into a vacuum state; the vacuum pumping interface which is convenient for pumping the cavity space in the isolation cylinder (302) to be in a vacuum state is arranged on the cylinder body of the isolation cylinder (302), the bottom mounting flange (303) is hollow, and a through hole which is communicated with the inner cavity of the bottom mounting flange (303) and the cavity space in the isolation cylinder (302) is arranged on the bottom mounting flange (303); a pressure sensor or a vacuum pressure gauge for monitoring the pressure of the cylinder cavity is also arranged on the top mounting flange (301);

the isolation valve (304) comprises a valve core (3044), a valve body (3041) and a valve cover (3043), wherein the upper part of the valve body is in an opening shape, the valve cover (3043) is fixed on the bottom mounting flange (303), and a flow port for flowing liquid hydrogen is formed in the valve cover (3043); the valve body (3041) is fixedly arranged at the bottom of the valve cover (3043) and is positioned below the circulation port, the valve body (3041) extends downwards into the liquid hydrogen container, and the valve body (3041) is provided with at least one drainage port (30411) for liquid hydrogen to flow into the valve body (3041); the cold end is a cold end assembly (1); the cold end assembly (1) comprises a cold end cylinder body (106) with an opening at the lower part, a cold end bottom cover (108) for sealing is fixedly arranged at the opening at the lower part of the cold end cylinder body (106), and a channel communicated with a valve core (3044) of the isolating valve (304) is formed in the cold end bottom cover (108); a cylindrical cold end bottom cover convex part (1081) is arranged on the lower side of the cold end bottom cover (108), a cold end bottom cover liquid inlet hydrogen hole (1082) is formed in the cold end bottom cover convex part (1081), and the outer diameter of the cold end bottom cover convex part (1081) is matched with the inner diameter of a flow port in the valve cover (3043);

the valve core (3044) and the valve cover (3043) are matched to realize the following two working states: when the valve core (3044) is abutted against the valve cover (3043), the flow port is blocked, and the liquid hydrogen in the liquid hydrogen container cannot be conveyed outwards; or, a cold end bottom cover protrusion (1081) on the lower side of the cold end bottom cover (108) is inserted into the flow port on the valve cover (3043), and the cold end bottom cover protrusion (1081) is pressed against the top of the valve core (3044), so that when the valve core (3044) is not abutted against the valve cover (3043), the drainage port (30411), the cold end bottom cover liquid hydrogen inlet hole (1082) and the flow port are communicated with each other, and liquid hydrogen in the liquid hydrogen container can be normally conveyed outwards; the valve core (3044) is a two-section stepped column with a thick upper part and a thin lower part, the thin lower half section of the valve core (3044) movably penetrates through the bottom of the valve body (3041), a compression spring (3042) sleeved on the lower half section of the valve core is arranged in the valve body (3041), one end, far away from the valve body (3041), of the compression spring (3042 is abutted to the upper half section of the valve core (3044), and when the compression spring (3042) is in a natural state, the compression spring (3042) presses the upper half part of the valve core (3044) to seal a flow port on the valve cover (3043).

2. A double acting reciprocating submerged liquid hydrogen pump according to claim 1, wherein the power section comprises a ambient temperature assembly (2) and a high pressure fluid power source (401); the normal-temperature assembly (2) comprises a normal-temperature piston (207) arranged in a normal-temperature cylinder body (205), wherein a normal-temperature piston sealing ring (206) used for filling a gap between the normal-temperature piston (207) and the inner wall of the cylinder body is sleeved on the normal-temperature piston (207); the high-pressure fluid power source (401) is respectively communicated with cylinder cavities at the upper side and the lower side of the normal-temperature piston (207) through two pipelines; the working states of the cylinder cavities on the upper side and the lower side of the normal-temperature piston (207) are different when in work, namely when the cylinder cavity on one side of the normal-temperature piston (207) enters fluid, the cylinder cavity on the other side of the normal-temperature piston (207) discharges the fluid; the upper end of the strut (202) penetrates through the bottom of the normal-temperature cylinder (205) to be connected with the normal-temperature piston (207), and the lower end of the strut (202) penetrates through the top of the cold-end cylinder (106) to be connected with the cold-end piston (104).

3. A double-acting type reciprocating submerged liquid hydrogen pump according to claim 2, characterized in that the room temperature assembly (2) comprises a room temperature cylinder (205) with an open upper part and a closed lower part, a sealed top cover (208) is arranged at the upper opening of the room temperature cylinder (205), and a sealed bottom cover (203) is arranged at the lower opening; the top cover (208) is provided with a top pipeline (209) communicated with a cylinder cavity above the normal-temperature piston (207), the bottom cover (203) is provided with a bottom pipeline (210) communicated with the cylinder cavity below the normal-temperature piston (207), and the top pipeline (209) and the bottom pipeline (210) are two pipelines communicated with the high-pressure fluid power source (401); the upper end of the supporting rod (202) penetrates through the bottom cover (203) to be connected with a normal-temperature piston (207), and a supporting rod normal-temperature sealing ring (204) is arranged at the contact position of the supporting rod (202) and the bottom cover (203).

4. A double acting reciprocating submerged liquid hydrogen pump according to claim 3, wherein the top line (209) and the bottom line (210) are both connected to a high pressure fluid power source (401) through a reversing valve (402), and the high pressure fluid power source (401) provides high pressure fluid power to only one of the top line (209) and the bottom line (210) through the reversing valve (402) at a time, and the reversing valve (402) is a three-position four-way reversing valve or a three-position five-way reversing valve.

5. A double acting, reciprocating submerged liquid hydrogen pump according to claim 3, wherein the liquid hydrogen pump has only its top cover (208) protruding outside the partition; the bottom pipeline (210) penetrates through the top cover (208) to enter the isolation part and then is communicated with a cylinder cavity below the normal-temperature piston (207) through the bottom cover (203); a liquid hydrogen outlet pipe for discharging liquid hydrogen conveys the liquid hydrogen to the outside through the top cover (208).

6. A double-acting type reciprocating submerged liquid hydrogen pump according to claim 2, characterized in that the cold end component (1) and the normal temperature component (2) are fixedly connected through a support tube (201), and the support rod (202) is arranged in the support tube (201) in a penetrating manner; the liquid hydrogen outlet pipe is spirally raised around the branch pipe (201).