KR100603053B1 - Flexible pipe for keeping flow pattern of cryogenic fluid uniform - Google Patents

Abstract

The present invention relates to a cryogenic corrugated pipe for securing a flow field, in particular in the piping for delivering a cryogenic liquid fluid; A circular upstream flange formed integrally with the first pipe; A straight pipe portion having the same inner diameter as the first pipe and formed to a thin thickness so as to coincide with the first pipe and the inner diameter so as to be joined to the end of the first pipe by welding; A downstream flange integrally formed with a second pipe having an inner diameter wider than an outer diameter of the straight pipe, and inserting the straight pipe into the second pipe; And positioned on the outer periphery of the straight pipe portion, characterized in that it comprises a corrugated pipe coupled to both ends of the end of the first pipe and the second pipe, respectively.

According to the present invention as described above it is possible to prevent the structure damage by thermal contraction in the cryogenic environment, such as liquid nitrogen or liquid oxygen at the same time to secure the flow field by placing a straight pipe portion inside the corrugated pipe.

Corrugated pipe, cryogenic, liquid, vibration, heat shrinkage, flow field

Description

Flexible pipe for keeping flow pattern of cryogenic fluid uniform

1 is a perspective view showing the configuration of a cryogenic corrugated pipe for securing a flow field according to the present invention,

2 is a cross-sectional view taken along line AA ′ of FIG. 1;

3 is an enlarged view illustrating main parts of FIG. 2;

<Explanation of symbols on main parts of the drawings>

110: upstream flange 111: first piping

113: bolt member 120: straight pipe portion

121: upstream 123: downstream

125: hollow 130: downstream flange

131: second pipe 133: bolt member

135: third space portion 140: corrugated pipe

141: first space portion 143: second space portion

The present invention relates to a corrugated pipe, and more particularly, in order to prevent a change in the flow field pattern of the fluid due to the bending inside the corrugated pipe, a straight pipe part is provided to maintain the flow form of the fluid at the front end of the flowmeter or the like. The present invention relates to a cryogenic corrugated pipe for securing a flow field capable of absorbing stress generation and preventing damage to a structure due to thermal contraction of a metal in an ultra low temperature state.

The bending caused by the wrinkles inside the corrugated pipe generally changes the flow of the fluid flowing therein. This leads to turbulent flow in the laminar flow, which is fatal in areas where fluid flow is important.

In particular, in the field of flow measurement, such as turbine type flow meter, the form of fluid flow upstream of the flow meter is one of the important factors for ensuring accurate flow rate.

It is preferable not to use a corrugated pipe upstream of a general flow meter. However, in order to prevent breakage due to heat shrinkage due to strong vibration or cryogenic environment from upstream, such corrugated pipe insertion is essential, but the conventional corrugated pipe form does not satisfy all the requirements. Fatigue breakdown caused by vibration and thermal stress conditions caused by cryogenic environment can not be solved simultaneously.

The present invention is to solve the above problems, by placing a straight pipe inside the corrugated pipe to ensure a flow field and at the same time ultra-low temperature for securing a flow field that can prevent structural damage due to heat shrinkage in the cryogenic environment, such as liquid nitrogen or liquid oxygen The purpose is to provide a corrugated tube for use.

Features of the present invention for achieving the above object,

In the piping for delivering the cryogenic liquid fluid; A circular upstream flange formed integrally with the first pipe; A straight pipe portion having the same inner diameter as the first pipe and formed to a thin thickness so as to coincide with the first pipe and the inner diameter so as to be joined to the end of the first pipe by welding; A downstream flange integrally formed with a second pipe having an inner diameter wider than an outer diameter of the straight pipe, and inserting the straight pipe into the second pipe; And positioned on the outer periphery of the straight pipe portion, characterized in that it comprises a corrugated pipe coupled to both ends of the end of the first pipe and the second pipe, respectively.

Here, a first space portion is formed between the outer periphery of the straight pipe portion and the inner periphery of the corrugated pipe.

Here, the straight pipe portion may have a plurality of hollows formed in the circumferential direction in the downstream portion so as to transfer the pressure increase due to the vaporization of cryogenic liquid to the inner passage to the inner passage so as to prevent the corrugated pipe from being damaged.

Here, between the outer peripheral edge of the downstream portion of the straight pipe portion and the inner circumferential edge of the second pipe, the straight pipe portion and the second pipe may be slipped to prevent breakage due to heat shrinkage of the second pipe due to the cryogenic environment. The second space portion is formed to be.

Here, between the downstream end of the straight pipe portion and the downstream flange to secure a flow field in consideration of the difference in the degree of heat shrinkage of the straight pipe portion and the second pipe and to prevent the fatigue fracture by the temperature and vibration at the same time The space part is formed.

Hereinafter, the configuration of the cryogenic corrugated pipe for securing the flow field according to the present invention in detail with reference to the accompanying drawings as follows.

1 is a perspective view showing the configuration of a cryogenic corrugated pipe for securing a flow field according to the present invention, Figure 2 is a cross-sectional view taken along line AA 'of Figure 1, Figure 3 is an enlarged view of the main portion of FIG.

1 to 3, the cryogenic corrugated pipe 100 for securing the flow field according to the present invention, the upstream flange 110, straight pipe portion 120, downstream flange 130, corrugated pipe 140 It consists of.

The upstream flange 110 is integrally protruded from the first pipe 111 having a constant inner diameter, the bolt member 113 is formed to extend the bolt on the downstream side.

The straight pipe portion 120 has the same inner diameter as the first pipe 111, is formed with a relatively thinner thickness, and the end of the upstream portion 121 and the first pipe so as to coincide the inner diameter of the first pipe (111) ( 111 is joined by welding. Here, the straight pipe portion 120 transmits the pressure increase due to the vaporization of the cryogenic liquid to the inner space to the first space portion 141, which will be described later, to prevent the corrugated pipe 140, which will be described below, from being damaged. A plurality of hollows 125 are formed at 123 in the circumferential direction.

The downstream flange 130 is integrally protruded from the second pipe 131 having an inner diameter wider than the outer diameter of the straight pipe portion 120, the bolt member 133 that can be fastened to the bolt from the downstream side is formed extending. Here, between the downstream end 123 of the straight pipe portion 120 and the downstream flange 130 in consideration of the difference in the heat shrinkage degree of the straight pipe portion 120 and the second pipe 131 to secure a flow field and at the same time And forming a third space portion 135 having a gap at a predetermined interval to prevent fatigue destruction due to vibration.

Corrugated pipe 140 is located on the outer periphery of the straight pipe portion 120, both ends are coupled to the ends of the first pipe 111 and the second pipe 131, respectively. Here, the first space portion 141 is formed between the outer periphery of the straight pipe portion 120 and the inner periphery of the corrugated pipe 140. Here, between the outer circumferential edge of the downstream part 123 of the straight pipe part 120 and the inner circumferential edge of the second pipe 131, the straight pipe part 120 and the second pipe 131 are slipped to cause the cryogenic environment. The second space part 143 is formed at a minute interval so as to prevent damage due to thermal contraction of the second pipe 131.

That is, the cryogenic corrugated pipe 100 for securing the flow field according to the present invention is formed in one piece by attaching both ends of the corrugated pipe 140 to the upstream flange 110 and the downstream flange 130 in a welded form. At this time, the straight pipe portion 120 is the upstream portion 121 is integrally formed by welding with the first pipe 111 on the basis of the fluid flow direction, the downstream portion 123 is the second space portion 143 and the third The clearance of the space 135 is fixed in a non-contact form with the second pipe 131.

Hereinafter, the operation of the cryogenic corrugated pipe for securing the flow field according to the present invention will be described in detail with reference to FIGS. 1 and 3.

First, the cryogenic corrugated pipe 100 for securing a flow field according to the present invention is installed in a piping system for dealing with cryogenic liquid fluids, such as aviation, rocket engine.

In such a state, when the ultra-low temperature liquid fluid such as liquid nitrogen or liquid oxygen flows to the straight pipe part 120, the liquid fluid is vaporized by heat transfer from the outside to form a space formed between the straight pipe part 120 and the corrugated pipe 140. In one space 141, a sudden pressure rise occurs. At this time, the pressure of the first space portion 141 is transmitted to the inner flow path through the straight pipe portion 120 by a plurality of hollows 125 formed in the straight pipe portion 120, the corrugated pipe 140 is damaged by a high pressure You can prevent it.

On the other hand, when the cryogenic liquid fluid flows to the straight pipe portion 120, the thermal deformation of the straight pipe portion 120 and the second pipe 131 of the downstream flange 130 due to the ultra-low temperature in the outside and the normal temperature pipe 120 is In this case, the second space part 143 may prevent the occurrence of thermal stress of the second pipe 131 and the straight pipe part 120.

In addition, the length in the axial direction is changed by the thermal deformation of the straight pipe portion 120 to interfere with the downstream flange 130, in this case, a third gap between the straight pipe portion 120 and the downstream flange 130 The space 135 may prevent interference due to a change in length.

Therefore, as described above, according to the present invention, in the piping system that handles cryogenic liquid fluids, the flow field is preserved in the field of dealing with aviation, rocket engines, and cryogenic, where the shape of the upstream flow field is important, such as a turbine flowmeter. At the same time, the system can be prevented from being damaged by the heat shrinkage of the metal due to the vibration and heat transfer of the pipe, and the corrugated pipe can be protected against the rapid vaporization of the cryogenic liquid fluid.

According to the cryogenic corrugated pipe for securing the flow field of the present invention configured as described above, by placing a straight pipe portion inside the corrugated pipe to secure the flow field and at the same time it can prevent the structure damage by heat shrinkage in the cryogenic environment, such as liquid nitrogen or liquid oxygen.

Claims (5)

delete A circular upstream flange 110 in which the first pipe 111 is integrally formed; A straight pipe portion 120 coupled to the first pipe by welding; A downstream flange 130 inserted into the second pipe; And a pipe located at an outer periphery of the straight pipe portion and delivering a cryogenic liquid fluid by a corrugated pipe 140 having both ends coupled to ends of the first and second pipes, respectively. The straight pipe portion 120 transmits a pressure increase due to vaporization of cryogenic liquid to the first space portion 141 to an internal flow path to prevent the corrugated pipe from being damaged by a plurality of hollows 125 in a circumferential direction downstream thereof. Ultra-low temperature corrugated pipe for securing the flow field, characterized in that formed. delete delete The method of claim 2, Between the downstream end of the straight pipe portion 120 and the downstream flange 130, The third space portion 135 is formed to secure the flow field in consideration of the difference between the heat shrinkage degree of the straight pipe portion and the second pipe and to prevent fatigue destruction due to temperature and vibration. Cryogenic tube for cryogenic use.

Images