Liquid oxygen stop valve for liquid rocket engine

Abstract

A liquid rocket engine liquid oxygen stop valve is composed of a cylinder, a piston, a valve body, a spring, a valve core, a valve seat and a one-way valve; wherein the one-way valve is located at the top of the stop valve, and the valve body is formed by an integrated process of a spherical shell, an internal cylinder and a cylindrical guide hole; a piston is arranged in the cylinder, and the piston divides the inner cavity of the cylinder into an upper closed cavity and a lower closed cavity, the upper closed cavity is connected to the one-way valve, and the lower closed cavity is connected to the control air port of the valve body; the piston is fixedly connected to the valve core through a thread; the cylindrical rod of the valve core passes through the cylindrical guide hole, and a spring is arranged between the upper end face of the valve core and the inner wall above the valve body, and the action of the spring makes the lower end face of the valve core fit tightly with the valve seat and achieves sealing; the valve seat is connected and sealed with the lower end face of the valve body through a flange structure. The technical solution of the present invention has an automatic closing function, which makes the sealing of ultra-low temperature and large-caliber stop valves more effective and reliable.

Description

Technical Field

[0001] The invention relates to a liquid oxygen stop valve for a liquid rocket engine, belongs to the technical fields of aerospace and liquid rockets, and is used for controlling the on-off of a high-pressure and ultra-low-temperature pipeline of a liquid rocket engine. Background Art

[0002] Liquid rocket engines, as the power unit of launch vehicles, are the core components of rocket takeoff. Liquid oxygen stop valves, as the control elements for starting and shutting down liquid rocket engines, are essential components for reliable engine operation. During the operation of liquid rocket engines, liquid oxygen and other ultra-low temperature (20K~90K) media need to be pressurized to 10MPa or even 20MPa. As the valve that controls the flow of media in the system pipeline, the sealing and reliability of the stop valve are extremely important. Due to the complexity of the system, the key to improving system reliability is to enable the valve to achieve mechanical automatic action.

[0003] At present, most small-diameter stop valves use a fixed connection between the valve core and the valve core. The valve core is connected to the valve core through a manual, electric or pneumatic actuator. The actuator is operated or controlled to drive the valve core and the valve core to move up and down to open and close the valve. The structure is relatively complex and requires two instructions, open and close, to realize the valve switch. This structure requires the movement of the valve core to be controlled by the actuator. Summary of the invention

[0004] The technical problem solved by the present invention is: using spring energy storage to realize automatic closing of the valve according to working conditions, and solving the problem that the exhaust port is connected to the external environment under complex external environment, affecting the normal operation of the valve at low temperature, resulting in reduced valve reliability;

[0005] The technical solution of the present invention is: a liquid rocket engine high-pressure liquid oxygen stop valve, comprising a cylinder (1), a piston (2), a valve body (3), a spring (4), a valve core (5), a valve seat (6) and a check valve (7); wherein the check valve (7) is located at the top of the stop valve and is arranged in a cylindrical hole at the upper part of the cylinder (1); the cylinder (1) is connected to the valve body (3) through a flange and the connection surface is sealed; the valve body (3) is composed of a spherical shell, an inner cylinder (3-2) and a cylindrical guide hole (3-1); a control air port is opened above the spherical shell; the spherical shell, the inner cylinder (3-2) and the cylindrical guide hole (3-1) are formed by integrated processing; a piston (2) is arranged in the cylinder (1); the piston (2) seals the inner cavity of the cylinder The valve body (3) is divided into an upper sealed chamber (21) and a lower sealed chamber (22), the upper sealed chamber (21) is connected to the one-way valve (7), and the lower sealed chamber (22) is connected to the control air port of the valve body (3); the piston (2) is fixedly connected to the cylindrical rod on the valve core (5) through a thread; the cylindrical rod of the valve core (5) passes through the guide hole (3-1) and is in clearance fit with the guide hole (3-1); the lower end of the valve core (5) is designed with a circular structure for sealing, and a spring (4) is arranged between the upper end face of the valve core (5) and the upper inner wall of the valve body (3), and the lower end face of the valve core (5) is tightly fitted with the valve seat (6) by the action of the spring (4) to achieve sealing; the valve seat (6) is connected to the lower end face of the valve body (3) through a flange structure and is sealed;

[0006] The one-way valve (7) is composed of a one-way valve core (7-1), a clamping ring (7-2), a filter screen (7-3) and a one-way valve spring (7-4); the one-way valve core (7-1) is pressed against the cylindrical hole of the cylinder (1) by the force of the one-way valve spring (7-4), the other end of the one-way valve spring (7-4) is arranged on the filter screen (7-3), and the filter screen is fixed in position by the clamping ring (7-2);

[0007] The one-way valve (7) and the cylinder (1) can also be designed as an integrated whole, which can prevent the humid air from the environment from entering the upper cavity of the piston (2), and the filter screen (13) is used as a spring seat, so that it also has a dustproof function, effectively preventing the influence of the external harsh environment on the low-temperature stop valve actuating cylinder, so that it has dustproof and waterproof functions;

[0008] Compared with the prior art, the advantages of the present invention are as follows: the present invention uses a movable connection between the valve core and the valve core, which effectively solves the problem of the valve core and the valve seat being misaligned at low temperatures, and improves the sealing reliability of the low-temperature high-pressure stop valve. In addition, the filter screen is used as a spring seat, which effectively prevents the one-way valve discharge hole from being exposed, so that on the basis of achieving one-way exhaust, even under harsh external environmental conditions, harmful media such as dust cannot enter the inside of the one-way valve;

[0009] The force of the system medium pressure on the valve core is used to maintain and close the valve core position, and when the system operating conditions change to the shutdown design point, the valve can be automatically closed under the action of the spring. It can simplify the valve control system, reduce system complexity, and improve system reliability;

[0010] In addition, ultra-low temperature makes the dust and humid air in the external environment have a fatal impact on the reliability of the stop valve, making the production and maintenance costs of the product high. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a structural diagram of the liquid oxygen stop valve of the present invention;

[0012] Figure 2 It is a left view of the liquid oxygen stop valve of the present invention;

[0013] Figure 3 This is a structural diagram of the one-way valve in the liquid oxygen stop valve described in the present invention. DETAILED DESCRIPTION

[0014] A high-pressure liquid oxygen stop valve for a liquid rocket engine, comprising a cylinder (1), a piston (2), a valve body (3), a spring (4), a valve core (5), a valve seat (6) and a check valve (7); wherein the check valve (7) is located at the top of the stop valve and is arranged in a cylindrical hole at the upper part of the cylinder (1); the cylinder (1) is connected to the valve body (3) via a flange and the connection surface is sealed; the valve body (3) is composed of a spherical shell, an inner cylinder (3-2) and a cylindrical guide hole (3-1); a control air port is opened above the spherical shell; the spherical shell, the inner cylinder (3-2) and the cylindrical guide hole (3-1) are formed by integrated processing; a piston (2) is arranged in the cylinder (1); the piston (2) divides the inner cavity of the cylinder into an upper and a lower chamber; The upper sealed chamber (21) is connected to the one-way valve (7), and the lower sealed chamber (22) is connected to the control air port of the valve body (3); the piston (2) is fixedly connected to the upper cylindrical rod of the valve core (5) through a thread; the cylindrical rod of the valve core (5) passes through the guide hole (3-1) and is in clearance fit with the guide hole (3-1); the valve core (5) is designed with a circular structure for sealing, and a spring (4) is arranged between the upper end face of the valve core (5) and the upper inner wall of the valve body (3), and the lower end face of the valve core (5) is tightly fitted with the valve seat (6) by the action of the spring (4) to achieve sealing; the valve seat (6) is connected to the lower end face of the valve body (3) through a flange structure and is sealed;

[0015] The one-way valve (7) is composed of a one-way valve core (7-1), a clamping ring (7-2), a filter screen (7-3) and a one-way valve spring (7-4); the one-way valve core (7-1) is pressed against the cylindrical hole of the cylinder (1) by the force of the one-way valve spring (7-4), the other end of the one-way valve spring (7-4) is arranged on the filter screen (7-3), and the filter screen is fixed in position by the clamping ring (7-2);

[0016] The one-way valve (7) and the cylinder (1) can also be designed as an integral whole, so as to prevent humid air from the environment from entering the upper cavity of the piston (2), and the filter screen (7-3) is used as a spring seat, so that it also has a dust-proof function;

[0017] During operation, the liquid oxygen output by the turbo pump of the liquid rocket engine enters the valve body (3) from the inlet of the stop valve of the present invention. At this time, the valve core (5) is in contact with the valve seat (6), so that the liquid medium cannot flow out from the outlet. When the liquid rocket engine is started, the liquid medium needs to flow out from the outlet. At this time, the gas cylinder of the liquid rocket engine outputs high-pressure gas to the control gas port above the spherical shell of the stop valve, so that the lower closed chamber (22) is filled with high-pressure gas, pushing the piston (2) to move upward, compressing the upper closed chamber (21), and the one-way valve (7) is opened to discharge the compressed gas inside; at the same time, the piston (2) drives the valve core (5) to move upward, and at this time, the lower end surface of the valve core (5) is separated from the valve seat (6), so that the liquid medium flows out from the outlet, and the upper end surface compresses the spring (4). When the upper end surface of the valve core (5) contacts the cylinder (3-2) arranged inside the valve body (3), the valve core (5) stops moving, and the piston (2) stops moving upward. When the pressure of the liquid oxygen flowing in from the inlet reaches a certain range (usually 7MPa~9MPa), so that the pressure of the liquid oxygen in the valve body (3) acting on the valve core (5) is equal to the compression force of the spring (4) and its gravity, the gas cylinder of the liquid rocket engine connected to the control gas port is removed. At this time, although the lower closed chamber (22) is connected to the outside atmosphere through the control gas port, so that the pressure change of the gas inside is the same as that of the outside atmosphere, the pressure of the liquid oxygen acting on the valve core (5) is equal to the compression force of the spring (4) and its gravity, so the valve core (5) will not move and still maintain Figure 2 When the pressure of the liquid oxygen flowing into the inlet decreases, the liquid oxygen pressure acting on the valve core (5) is less than the force of the spring (4) and its gravity. At this time, the valve core (5) moves downward under the force of the spring (4), so that the stop valve is closed and returns to the Figure 1 Status shown;

[0018] Preferably, the one-way valve (7) and the cylinder (1) can be designed as an integrated whole, which can prevent the humid air from the environment from entering the upper cavity of the piston (2), and the filter (7-3) is used as a spring seat, so that it also has a dustproof function. It effectively prevents the influence of the external harsh environment on the low-temperature stop valve actuating cylinder, so that it has dustproof and waterproof functions;

[0019] The above is only a specific implementation of the present invention, but the protection of the present invention is not limited thereto. Any improvement without substantial change made by those skilled in the art without changing the principle shall also be regarded as the protection scope of the present invention.

[0020] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in this field.

Claims

1. A liquid rocket engine high pressure liquid oxygen stop valve, Features: The valve body (3) is composed of a cylinder (1), a piston (2), a valve body (3), a spring (4), a valve core (5), a valve seat (6) and a one-way valve (7); wherein the one-way valve (7) is located at the top of the stop valve and is arranged in the cylindrical hole at the upper part of the cylinder (1); the cylinder (1) is connected to the valve body (3) through a flange and the connection surface is sealed; the valve body (3) is composed of a spherical shell, an internal cylinder (3-2) and a cylindrical guide hole (3-1); a control air port is opened above the spherical shell; the spherical shell, the internal cylinder (3-2) and the cylindrical guide hole (3-1) are formed by integrated processing; a piston (2) is arranged in the cylinder (1); the piston (2) divides the inner cavity of the cylinder into an upper closed cavity (21) and a lower closed cavity (22). 2), the upper sealed chamber (21) is connected to the one-way valve (7), and the lower sealed chamber (22) is connected to the control air port of the valve body (3); the piston (2) is fixedly connected to the cylindrical rod designed on the upper part of the valve core (5) through a thread; the cylindrical rod of the valve core (5) passes through the cylindrical guide hole (3-1) and is in a clearance fit with the cylindrical guide hole (3-1); the lower end of the valve core (5) is designed with a circular structure for sealing, and a spring (4) is arranged between the upper end face of the valve core (5) and the upper inner wall of the valve body (3), and the lower end face of the valve core (5) and the valve seat (6) are tightly fitted and sealed by the action of the spring (4); the valve seat (6) is connected to the lower end face of the valve body (3) through a flange structure and sealed; The one-way valve (7) is composed of a one-way valve core (7-1), a clamping ring (7-2), a filter screen (7-3) and a one-way valve spring (7-4); the one-way valve core (7-1) is pressed against the cylindrical hole of the cylinder (1) by the action force of the one-way valve spring (7-4), the other end of the one-way valve spring (7-4) is arranged on the filter screen (7-3), and the filter screen is fixed in position by the clamping ring (7-2).

2. The liquid rocket engine high pressure liquid oxygen stop valve according to claim 1, Features: The one-way valve (7) and the cylinder (1) can also be designed as an integrated whole, which can prevent the ambient humid air from entering the upper cavity of the piston (2), and the filter screen (7-3) is used as a spring seat, so that it also has a dustproof function.

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