JP2009250567A - Flooded type shell-and-tube exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress retention of lubricating oil by a simple structure without requiring cost. <P>SOLUTION: In this flooded type shell-and-tube exchanger, multiple heat-transfer pipes 2 in which cooled fluid W is made to flow are arranged within a body 1 in which a refrigerant is made to flow. A refrigerant passage 4 in which a refrigerant is made to flow toward a refrigerant outlet 3 provided in the body 1 at predetermined speed is formed above a liquid level L within the body 1, and lubricating oil included in a liquid refrigerant X is made to flow out to the refrigerant outlet 3 together with the refrigerant flowing on the refrigerant passage 4 at the predetermined speed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a shell-and-tube type full-tube multi-tube heat exchanger used as a full-cooler.

  For example, as shown in FIG. 2, a shell-and-tube type liquid-filled multi-tube heat exchanger has a large number of heat transfer tubes in which a fluid to be cooled (for example, water) flows in a body 1 in which a liquid refrigerant X flows. In the body 1, the heat transfer tubes 2, 2... Through which the fluid to be cooled circulates are immersed in the liquid refrigerant X. Reference numeral 3 denotes a refrigerant outlet (in other words, a compressor suction pipe).

  This type of liquid-filled multi-tube heat exchanger has been well known as disclosed in Patent Document 1.

JP-A-8-254373.

  When the full-liquid multitubular heat exchanger having the above configuration is used as a full-liquid cooler, as shown in FIG. 3, the compressor 11, the condenser 12, the expansion mechanism 13, and the full-liquid multitubular heat exchanger. It is used by being incorporated in a refrigeration cycle consisting of 14. Reference numeral 11 a is a suction portion of the compressor 11, and 11 b is a discharge portion of the compressor 11.

  In the case of the refrigeration cycle, the gas refrigerant compressed by the compressor 11 is condensed and liquefied in the condenser 12 to become liquid refrigerant, and the liquid refrigerant is decompressed by the expansion mechanism 13 and then functions as an evaporator. The fluid to be cooled (for example, water W) flowing through the body 1 is cooled in the process of being led to the multi-tube heat exchanger 14 and evaporating and evaporating in the full-liquid multi-tube heat exchanger 14. Yes. By the way, the flow rate of the liquid refrigerant containing the lubricating oil disappears in the central part of the body of the full-liquid multitubular heat exchanger 14, and the lubricating oil does not reach the refrigerant outlet (in other words, the compressor suction pipe). As a result, there was a problem that the lubricating oil collected inside the fuselage. In order to cope with this problem, in the conventional system, as shown in FIG. 2, a refrigerant pressure feed such as an ejector or a pump is provided between the body 1 of the full-tube type multi-tube heat exchanger and the suction portion 11a of the compressor 11. An oil return pipe 16 provided with a means 15 is separately provided to return the lubricating oil accumulated in the body 1 to the suction portion 11a of the compressor 11 together with the liquid refrigerant X.

  However, in the conventional method, it is necessary to separately provide the oil return pipe 16, and an ejector or a pump is required as the refrigerant pressure feeding means 16, which causes a new problem of increasing the cost.

  The present invention has been made in view of the above points, and an object of the present invention is to prevent accumulation of lubricating oil with a simple structure without cost.

  In the present invention, as a first means for solving the above problem, a full liquid type in which a large number of heat transfer tubes 2, 2.. In the multi-tubular heat exchanger, a refrigerant passage 4 is formed above the liquid level L in the body 1 so that the refrigerant flows at a predetermined speed toward the refrigerant outlet 3 provided in the body 1.

  With the configuration described above, the lubricating oil contained in the liquid refrigerant X together with the refrigerant flowing through the refrigerant passage 4 at a predetermined speed flows out to the refrigerant outlet 3, and the refrigerant passage 4 is provided in the body 1. With the structure, accumulation of lubricating oil in the body 1 is suppressed. Therefore, when it is incorporated in the refrigeration cycle, oil can be returned to the suction portion of the compressor, and the shortage of lubricating oil in the compressor is solved.

  In the present invention, as a second means for solving the above-mentioned problem, in the full-liquid multitubular heat exchanger provided with the first means, the refrigerant passage 4 is connected to the inlet of the refrigerant outlet 3. It can also be formed between the cover member 5 that covers the side and the inner surface of the fuselage 1, and in such a configuration, by adding a simple structure in which the cover member 5 is disposed in the fuselage 1, This prevents the accumulation of lubricating oil on the surface.

  In the present invention, as a third means for solving the above-described problem, in the full-liquid multitubular heat exchanger provided with the second means, the cover member 5 is connected to the inner surface of the body 1. A plate-shaped member having substantially the same shape can be used. In such a case, the body 1 is added by adding a simple structure in which a plate-shaped member having the same shape as the inner surface of the body 1 is added to the body 1. The accumulation of lubricating oil in the inside will be suppressed.

  In the present invention, as a fourth means for solving the above-described problems, in the full-tube type multi-tube heat exchanger provided with the first, second or third means, the size of the refrigerant passage 4 is increased. Further, the flow rate of the refrigerant flowing through the refrigerant passage 4 can be set to be about 0.5 m / s. In such a configuration, the mixing ratio of the lubricating oil to the refrigerant flowing through the refrigerant passage 4 is It becomes optimal and the accumulation of lubricating oil in the body 1 is effectively suppressed.

  In the present invention, as a fifth means for solving the above problems, in the full-tube type multi-tube heat exchanger provided with the second, third or fourth means, the cover member 5 It can also be provided over the entire length of the body 1, and in such a case, even in the case of a liquid-filled multi-tube heat exchanger provided with the body 1 having a plurality of refrigerant outlets, a single cover member is used. A plurality of refrigerant outlets can be covered, and the structure can be simplified.

  According to the first means of the present invention, a liquid-filled multi-tube heat exchanger comprising a large number of heat transfer tubes 2, 2.. The refrigerant passage 4 in which the refrigerant flows at a predetermined speed toward the refrigerant outlet 3 provided in the trunk 1 is formed above the liquid level L in the fuselage 1, and together with the refrigerant flowing in the refrigerant passage 4 at a predetermined speed Since the lubricating oil contained in the liquid refrigerant X flows out to the refrigerant outlet 3, it is possible to suppress the accumulation of the lubricating oil in the fuselage 1 with a simple structure in which the refrigerant passage 4 is provided in the fuselage 1. There is an effect that can be. Therefore, when it is incorporated in the refrigeration cycle, oil can be returned to the suction portion of the compressor, and the shortage of lubricating oil in the compressor can be solved.

  As in the second means of the present invention, in the liquid-filled multi-tubular heat exchanger provided with the first means, the refrigerant passage 4 is covered with the cover member 5 that covers the inlet side of the refrigerant outlet 3 and the cover member 5. It can also be formed between the inner surface of the fuselage 1, and in such a configuration, the addition of a simple structure in which the cover member 5 is disposed in the fuselage 1 causes the accumulation of lubricating oil in the fuselage 1. It will be suppressed.

  As in the third means of the present invention, in the full-tube type tube heat exchanger provided with the second means, the cover member 5 is formed by a plate-like member having substantially the same shape as the inner surface of the body 1. In such a case, the addition of a simple structure in which a plate-like member having the same shape as the inner surface of the fuselage 1 is added to the fuselage 1 makes it possible for the lubricating oil to accumulate in the fuselage 1. Will be suppressed.

  As in the fourth means of the present invention, in the full-tube type multi-tubular heat exchanger provided with the first, second or third means, the size of the refrigerant passage 4 is set so that the refrigerant passage 4 The flow rate of the flowing refrigerant can be set to be about 0.5 m / s. In such a configuration, the mixing ratio of the lubricating oil to the refrigerant flowing through the refrigerant passage 4 is optimal, and the flow rate into the body 1 is increased. The accumulation of lubricating oil is effectively suppressed.

  As in the fifth means of the present invention, in the full-tube type multi-tube heat exchanger provided with the second, third or fourth means, the cover member 5 is extended over the entire length of the body 1. In such a case, even in the case of a full-liquid multitubular heat exchanger having a body 1 having a plurality of refrigerant outlets, a single cover member 5 covers the plurality of refrigerant outlets. Therefore, the structure can be simplified.

  Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

  As shown in FIG. 1, this full-liquid multitubular heat exchanger is configured by arranging a large number of heat transfer tubes 2, 2... Through which a fluid W to be cooled flows in a body 1 through which refrigerant flows. ing. Reference numeral 3 denotes a refrigerant outlet (in other words, a compressor suction pipe).

  When the full-liquid multitubular heat exchanger having the above configuration is used as a full-liquid cooler, as shown in FIG. 3, the compressor 11, the condenser 12, the expansion mechanism 13, and the full-liquid multitubular heat exchanger. It is used by being incorporated in a refrigeration cycle consisting of 14.

  In the present embodiment, a refrigerant passage 4 in which the refrigerant flows at a predetermined speed or more toward the refrigerant outlet pipe 3 provided in the trunk 1 is formed above the liquid level L in the trunk 1. The refrigerant passage 4 is formed between a cover member 5 that covers the inlet side of the refrigerant outlet pipe 3 and the inner surface of the body 1. The cover member 5 is configured by a plate-like member having substantially the same shape as the inner surface of the body 1, and is provided over the entire length of the body 1. The size of the refrigerant passage 4 is set so that the flow rate of the refrigerant flowing through the refrigerant passage 4 is about 0.5 m / s.

  In the case of the refrigeration cycle, the gas refrigerant compressed by the compressor 11 is condensed and liquefied in the condenser 12 to become liquid refrigerant, and the liquid refrigerant is decompressed by the expansion mechanism 13 and then functions as an evaporator. The fluid to be cooled (for example, water W) flowing through the heat transfer tubes 2, 2... Is cooled in the process of being led to the multi-tube heat exchanger 14 and evaporating and evaporating in the full-liquid multi-tube heat exchanger 14. It is supposed to be. At this time, the flow rate of the liquid refrigerant containing the lubricating oil disappears at the center of the body 1 in the full-liquid multitubular heat exchanger 14, and the lubricating oil reaches the refrigerant outlet 3 (in other words, the compressor suction pipe). As a result, the lubricating oil may accumulate in the body 1.

  However, in the present embodiment, since the liquid level L of the liquid refrigerant X in the body 1 undulates due to the evaporating action, it flows through the refrigerant passage 4 at a predetermined speed (for example, about 0.5 m / s). Lubricating oil contained in the liquid refrigerant X together with the refrigerant flows out to the refrigerant outlet pipe 3, and a simple structure in which the cover member 5 made of a plate-like member is provided in the body 1 to provide the refrigerant passage 4. The accumulation of lubricating oil in the body 1 is suppressed. Therefore, when incorporated in the refrigeration cycle, the oil can be returned to the suction portion 11a of the compressor 11, and the shortage of lubricating oil in the compressor 11 can be resolved. In addition, since the size of the refrigerant passage 4 is set so that the flow velocity of the refrigerant flowing through the refrigerant passage 4 is about 0.5 m / s, the mixing ratio of the lubricating oil to the refrigerant flowing through the refrigerant passage 4 is optimal. Thus, the accumulation of lubricating oil in the body 1 is effectively suppressed. Further, since the cover member 5 is provided over the entire length of the body 1, one cover member is provided even in the case of a full-liquid multitubular heat exchanger provided with the body 1 having a plurality of refrigerant outlets. 5, it becomes possible to cover a plurality of refrigerant outlets, and the structure can be simplified.

  By the way, in the case of a full-liquid multitubular heat exchanger provided with the body 1 having a plurality of refrigerant outlets, the cover member 5 can be equally arranged so as to correspond to the refrigerant outlets.

  In addition, as the refrigerant passage, there is a case where a flat tube communicating with the refrigerant outlet is disposed in the body other than that formed between the cover member and the inner surface of the body, and the inside of the flat tube is used as the refrigerant passage. .

  The invention of the present application is not limited to the above-described embodiment, and it is needless to say that the design can be appropriately changed without departing from the gist of the invention.

It is an expanded sectional view of a full liquid type multi-tube heat exchanger concerning an embodiment of the invention of this application. It is an expanded sectional view of the conventional full liquid type multi-tube heat exchanger. This is a refrigeration cycle using a full-liquid multi-tube heat exchanger.

Explanation of symbols

1 is fuselage 2 is heat transfer pipe 3 is refrigerant outlet (compressor suction pipe)
4 is a refrigerant passage 5 is a cover member (plate-shaped member)
L is liquid level W is fluid to be cooled (water)
X is liquid refrigerant

Claims (5)

  A full-liquid multitubular heat exchanger in which a large number of heat transfer tubes (2), (2),... In which a fluid to be cooled (W) flows is disposed in a fuselage (1) in which a refrigerant flows. A refrigerant passage (4) in which the refrigerant flows at a predetermined speed toward the refrigerant outlet (3) provided in the fuselage (1) is formed above the liquid level (L) in the fuselage (1). A full liquid multi-tube heat exchanger.   The full liquid mold according to claim 1, wherein the refrigerant passage (4) is formed between a cover member (5) covering an inlet side of the refrigerant outlet (3) and an inner surface of the body (1). Multi-tube heat exchanger. The full-liquid multitubular heat exchanger according to claim 2, wherein the cover member (5) is constituted by a plate-like member having substantially the same shape as the inner surface of the body (1). The size of the refrigerant passage (4) is set so that the flow velocity of the refrigerant flowing through the refrigerant passage (4) is about 0.5 m / s. Fully filled multitubular heat exchanger as described. The full-tube type multi-tube heat exchanger according to any one of claims 2 to 4, wherein the cover member (5) is provided over the entire length of the body (1).

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