A liquid nitrogen discharge pipe

Abstract

The present invention discloses a liquid nitrogen discharge pipe, comprising an outer exhaust pipe, a middle exhaust pipe, an inner exhaust pipe, a heating wire, a heating plate and a sleeve, wherein the outer exhaust pipe is sleeved with a middle exhaust pipe, the middle exhaust pipe is sleeved with an inner exhaust pipe, a first cavity is formed between the inner wall of the outer exhaust pipe and the outer wall of the middle exhaust pipe, a second cavity is formed between the inner wall of the middle exhaust pipe and the inner exhaust pipe, the output end of the outer exhaust pipe is sealed with the outer wall of the inner exhaust pipe, and one end of the middle exhaust pipe close to the input end of the outer exhaust pipe is a sealing end, so that nitrogen flows in the first cavity, the second cavity and the inner cavity of the inner exhaust pipe in an S-shaped direction. The present invention has the advantage that the flow of nitrogen in the S-shaped direction can not only avoid the nitrogen exhaust pipe from being too long, but also increase the flow resistance of nitrogen during the flow process, enhance the heat exchange effect between nitrogen and the pipe wall, and prevent the nitrogen from frosting the pipe during the transportation process.

Description

Technical Field

[0001] The invention relates to the technical field of liquid nitrogen, in particular to a liquid nitrogen discharge pipe. Background Art

[0002] Liquid nitrogen tanks can generally be divided into two types: liquid nitrogen storage tanks and liquid nitrogen transport tanks. Storage tanks are mainly used for static storage of liquid nitrogen indoors and are not suitable for long-distance transportation in working conditions. Liquid nitrogen transport tanks have been specially designed to be shockproof in order to meet transportation conditions. In addition to static storage, they can also be used for transportation when filled with liquid nitrogen, but violent collisions and vibrations should also be avoided.

[0003] For example, a Chinese utility model patent document with publication number CN213747541U discloses an air separation device that is conducive to shortening maintenance time, in which it is disclosed that the cold storage box is connected to the liquid nitrogen tank through a liquid nitrogen discharge pipe. However, when the liquid nitrogen is discharged from the liquid nitrogen tank, it changes from liquid to gas, which will cause frost and condensation on the liquid nitrogen discharge pipe, or even freeze, blocking the liquid nitrogen discharge pipe, resulting in exhaust obstruction, affecting the normal use of the liquid nitrogen tank, and even causing the liquid nitrogen tank to be over-pressurized and explode. Summary of the invention

[0004] The technical problem to be solved by the present invention is how to prevent the liquid nitrogen discharge pipe from frosting.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A liquid nitrogen discharge pipe comprises an outer exhaust pipe, a middle exhaust pipe, an inner exhaust pipe, a heating wire, a heating plate and a sleeve, wherein the middle exhaust pipe is sleeved in the outer exhaust pipe, and the inner exhaust pipe is sleeved in the middle exhaust pipe, a first cavity is formed between the inner wall of the outer exhaust pipe and the outer wall of the middle exhaust pipe, and a second cavity is formed between the inner wall of the middle exhaust pipe and the inner exhaust pipe, the output end of the outer exhaust pipe is sealed with the outer wall of the inner exhaust pipe, and one end of the middle exhaust pipe close to the input end of the outer exhaust pipe is a sealed end, so that nitrogen flows in the first cavity, the second cavity and the inner cavity of the inner exhaust pipe along an S-shaped direction; the heating wire is wound around the outer wall of the outer exhaust pipe, and the outer exhaust pipe, the middle exhaust pipe and the inner exhaust pipe are all provided with heating plates connected to the heating wire, and the output end of the outer exhaust pipe is also sleeved.

[0007] The S-shaped flow of nitrogen can not only avoid the nitrogen exhaust pipe from being too long, but also increase the flow resistance of nitrogen during the flow process, enhance the heat exchange effect between nitrogen and the pipe wall, and prevent the nitrogen from frosting the pipe during transportation. In addition, a sleeve is installed on the outside of the inner wall of the outer exhaust pipe outside the nitrogen tank to prevent the outer exhaust pipe from directly exchanging heat with the indoor air through radiation and convection, thereby preventing condensed water from forming on the outside of the outer exhaust pipe and flowing back into the tank.

[0008] Preferably, one end of the sleeve close to the input end of the outer exhaust pipe is also provided with an external thread.

[0009] Preferably, a temperature control system is also fixed on the sleeve, and the temperature control system includes a control box, a temperature sensor and a control system. The control box is fixed on the sleeve, and a wire hole is provided on the control box. The heating wire passes through the wire hole and extends into the control box to be electrically connected to the control system. The collection end of the temperature sensor passes through the sleeve and the inner exhaust pipe in turn and extends into the inner cavity of the inner exhaust pipe. The temperature sensor is electrically connected to the control system.

[0010] By collecting the temperature of the nitrogen when it is discharged through a temperature sensor to control the heating temperature of the heating wire, the exhaust port temperature can be kept within a reasonable range, avoiding energy waste caused by excessive temperature and achieving the purpose of energy saving; in addition, the nitrogen exhaust pipe has a simple structure and low cost.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] 1. The S-shaped flow of nitrogen can not only avoid the nitrogen exhaust pipe from being too long, but also increase the flow resistance of nitrogen during the flow process, enhance the heat exchange effect between nitrogen and the pipe wall, and prevent the nitrogen from frosting the pipe during transportation. In addition, a sleeve is installed on the outside of the inner wall of the outer exhaust pipe outside the nitrogen tank to prevent the outer exhaust pipe from directly exchanging heat with the indoor air through radiation and convection, thereby preventing condensed water from forming on the outside of the outer exhaust pipe and flowing back into the tank.

[0013] 2. The temperature of the nitrogen when it is discharged is collected by the temperature sensor to control the heating temperature of the heating wire, so that the exhaust port temperature can be kept within a reasonable range, avoiding energy waste caused by excessive temperature and achieving the purpose of energy saving; in addition, the outer exhaust pipe has a simple structure and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of an embodiment of the present invention;

[0015] Figure 2 It is a cross-sectional view of an embodiment of the present invention. DETAILED DESCRIPTION

[0016] In order to facilitate those skilled in the art to understand the technical solution of the present invention, the technical solution of the present invention is further described in conjunction with the accompanying drawings of the specification.

[0017] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0018] In this application, unless otherwise expressly specified and limited, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise clearly and specifically limited.

[0019] See also Figure 1 and Figure 2 The present embodiment discloses a liquid nitrogen exhaust pipe, comprising an outer exhaust pipe 1, a middle exhaust pipe 2, an inner exhaust pipe 3, a heating wire 4, a heating plate 5, a sleeve 6 and a temperature control system. The outer exhaust pipe 1 is sleeved with the middle exhaust pipe 2, the middle exhaust pipe 2 is sleeved with the inner exhaust pipe 3, a first cavity 7 is formed between the inner wall of the outer exhaust pipe 1 and the outer wall of the middle exhaust pipe 2, a second cavity 8 is formed between the inner wall of the middle exhaust pipe 2 and the inner exhaust pipe 3, and the output end of the outer exhaust pipe 1 is sealed and connected to the outer wall of the inner exhaust pipe 3. The end of the middle exhaust pipe 2 close to the input end of the outer exhaust pipe 1 is a sealed end, so that the nitrogen flows in the first cavity 7, the second cavity 8 and the inner cavity of the inner exhaust pipe 3 along the S-shaped direction; the heating wire 4 is wound around the outer wall of the outer exhaust pipe 1, and the outer exhaust pipe 1, the middle exhaust pipe 2 and the inner exhaust pipe 3 are all provided with a heating plate 5 connected to the heating wire 4. The output end of the outer exhaust pipe 1 is also sleeved with a sleeve 6, and the end of the sleeve 6 close to the input end of the outer exhaust pipe 1 is also provided with an external thread 61 that can be threadedly connected to the nitrogen tank.

[0020] The nitrogen in the nitrogen tank passes through the first cavity 7 between the inner wall of the outer exhaust pipe 1 and the middle exhaust pipe 2, then enters the second cavity 8 between the inner wall of the middle exhaust pipe 2 and the inner exhaust pipe 3, and finally enters the inner cavity of the inner exhaust pipe 3 and is discharged. During the flow of nitrogen in the first cavity 7, the second cavity 8 and the inner cavity of the inner exhaust pipe 3 along the S-shaped direction, the heating wire 4 heats the inner wall of the outer exhaust pipe 1 and the heating plate 5, thereby heating the nitrogen during the flow process; the S-shaped flow of nitrogen can not only avoid the nitrogen exhaust pipe from being too long, but also increase the flow resistance of nitrogen during the flow process, enhance the heat exchange effect between nitrogen and the pipe wall, and prevent the nitrogen from frosting the pipe during the transportation process. In addition, a sleeve 6 is installed on the outer inner wall of the outer exhaust pipe 1 outside the nitrogen tank to prevent the outer exhaust pipe from directly exchanging radiation heat and convection heat with the indoor air, thereby preventing condensed water from forming outside the outer exhaust pipe and flowing back into the tank.

[0021] The temperature control system includes a control box 9, a temperature sensor 10 and a control system (not shown in the figure). The control box 9 is fixed on the sleeve 6. The control box 9 is provided with a wire hole. The heating wire 4 passes through the wire hole and extends into the control box 9 to be electrically connected to the control system. The collection end of the temperature sensor 10 passes through the sleeve 9 and the inner exhaust pipe 3 in sequence and extends into the inner cavity of the inner exhaust pipe 3 to collect the temperature of nitrogen when it is discharged. The temperature sensor 10 is electrically connected to the control system.

[0022] By collecting the temperature of the nitrogen when it is discharged through the temperature sensor 10 to control the heating temperature of the heating wire 4, the exhaust port temperature can be kept within a reasonable range, avoiding energy waste caused by excessive temperature, and achieving the purpose of energy saving; in addition, the nitrogen exhaust pipe has a simple structure and low cost.

[0023] The working principle of the present invention is as follows: the outer exhaust pipe 1 not covered by the sleeve 6 is inserted into the nitrogen tank, the external thread 61 on the sleeve 6 is connected to the thread of the nitrogen tank, and the heating wire 4 is turned on for heating through the control system. The nitrogen in the gas tank passes through the first cavity 7 between the inner wall of the outer exhaust pipe 1 and the middle exhaust pipe 2, and then enters the second cavity 8 between the inner wall of the middle exhaust pipe 2 and the inner exhaust pipe 3, and finally enters the inner cavity of the inner exhaust pipe 3 and is discharged. During the flow of nitrogen in the first cavity 7, the second cavity 8 and the inner cavity of the inner exhaust pipe 3 along the S-shaped direction, the heating wire 4 heats the inner wall of the outer exhaust pipe 1 and the heating plate 5, thereby heating the nitrogen during the flow; and the temperature of the nitrogen when discharged is collected by the temperature sensor 10 to control the heating temperature of the heating wire 4, so that the temperature of the nitrogen discharge is within a reasonable range.

[0024] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention, and any reference numerals in the claims should not be regarded as limiting the claims involved.

[0025] The embodiments described above only represent implementation methods of the invention. The protection scope of the present invention is not limited to the embodiments described above. For those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A liquid nitrogen discharge pipe, characterized in that: The utility model comprises an outer exhaust pipe, a middle exhaust pipe, an inner exhaust pipe, a heating wire, a heating plate and a sleeve, wherein the middle exhaust pipe is sleeved in the outer exhaust pipe, the inner exhaust pipe is sleeved in the middle exhaust pipe, a first cavity is formed between the inner wall of the outer exhaust pipe and the outer wall of the middle exhaust pipe, a second cavity is formed between the inner wall of the middle exhaust pipe and the inner exhaust pipe, the output end of the outer exhaust pipe is sealed with the outer wall of the inner exhaust pipe, and the end of the middle exhaust pipe close to the input end of the outer exhaust pipe is a sealing end, so that nitrogen flows in the first cavity, the second cavity and the inner cavity of the inner exhaust pipe along an S-shaped direction; the heating wire is wound around the outer wall of the outer exhaust pipe, the outer exhaust pipe, the middle exhaust pipe and the inner exhaust pipe are all provided with heating plates connected with the heating wire, and the output end of the outer exhaust pipe is also sleeved; the outer exhaust pipe not sleeved by the sleeve is inserted into the nitrogen tank.

2. A liquid nitrogen discharge pipe according to claim 1, characterized in that: An end of the sleeve close to the input end of the outer exhaust pipe is also provided with an external thread.

3. A liquid nitrogen discharge pipe according to claim 1, characterized in that: A temperature control system is also fixed on the sleeve, and the temperature control system includes a control box, a temperature sensor and a control system. The control box is fixed on the sleeve, and a wire hole is provided on the control box. The heating wire passes through the wire hole and extends into the control box to be electrically connected to the control system. The collection end of the temperature sensor passes through the sleeve and the inner exhaust pipe in turn and extends into the inner cavity of the inner exhaust pipe. The temperature sensor is electrically connected to the control system.

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