JP2013068358A - Twisted tube type heat exchanger with different diameter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive twisted tube type heat exchanger with a different diameter capable of suppressing flow interruption of high temperature water even when a scale adheres thereto due to the high temperature water, and effectively exchanging heat.SOLUTION: The twisted tube type heat exchanger with a different diameter includes a water pipe 3 provided with a plurality of lines of spiral grooves 2 in the outer periphery and a plurality of refrigerant pipes 4 wound along the spiral grooves 2 in the outer periphery of the water pipe 3. The outlet of the water pipe 3 continuously includes the spiral grooves 2 and the plurality of refrigerant pipes 4 in the outer periphery, and wherein an inner diameter of the outlet is larger than an inner diameter of an inlet.

Description

  The present invention relates to a different diameter twisted tube heat exchanger for promoting heat exchange between water and a refrigerant, for example, a different diameter twisted tube heat exchanger for a heat pump water heater.

A water-refrigerant heat exchanger that performs heat exchange between water and a refrigerant uses a torsion pipe having a spiral groove on the outer periphery for the water pipe, and the refrigerant pipe from the outer peripheral side along the spiral groove of the water pipe. It is a heat exchanger in which a water pipe and a refrigerant pipe are wound and heat-transfer joined to each other by solder, brazing material, etc., and performs heat exchange between water flowing in the water pipe and refrigerant flowing in the refrigerant pipe.
Moreover, the spiral groove on the outer periphery of the water pipe generates a turbulent flow on the water side, and the effect thereof improves the heat exchange performance.

  By the way, in the conventional water-refrigerant heat exchanger that performs heat exchange between the water flowing in the water pipe and the refrigerant flowing in the refrigerant pipe, depending on the water to be used, the scale ( For example, there is a problem that calcium carbonate) adheres and accumulates, and the flow of hot water is obstructed.

Therefore, conventionally, a sufficient flow cross-sectional area between the refrigerant pipe and the water pipe is ensured so as not to hinder the flow of hot water even if the scale accumulates (for example, see Patent Document 1).
In addition, a proposal has been made that the water pipe is made of a synthetic resin so that it can be easily peeled off even if the scale adheres, and scale accumulation is effectively prevented (see, for example, Patent Document 2).
Moreover, the proposal which suppresses deposition of a scale by using the copper alloy pipe | tube containing 0.005-0.02 mass% Zr is also made | formed (for example, refer patent document 3).

JP 2006-046877 A JP 2009-144932 A JP 2010-139101 A

  However, as in Patent Document 1, when the outer diameter of the water pipe is formed over the entire length of the gas cooler or the outlet side is formed with a pipe having a large diameter, the material cost increases, the productivity decreases due to an increase in the number of parts, and the joints increase. There is a concern about reliability degradation.

  In addition, as in Patent Document 2 and Patent Document 3, when a copper pipe made of synthetic resin or added with special elements is used for water piping, there is a problem that the selection range of material selection and processing method becomes very narrow. Arise.

  The present invention has been made in order to solve the above-described problems, and is an inexpensive different-diameter torsion pipe that can suppress the flow inhibition of high-temperature water even when scales due to high-temperature water adhere and can efficiently exchange heat. An object is to provide a shape heat exchanger.

  The different diameter torsion tube heat exchanger according to the present invention includes a water pipe having a different diameter provided with a plurality of spiral grooves on the outer periphery, and a plurality of refrigerants wound along the spiral grooves on the outer periphery of the water pipe. And an outlet part of the water pipe is provided with the spiral groove and the plurality of refrigerant pipes continuously on the outer periphery, and the inner diameter of the outlet part is larger than the inner diameter of the inlet part.

  In the different diameter torsion tube heat exchanger according to the present invention, the outlet portion of the water pipe has a spiral groove and a plurality of refrigerant pipes on the outer periphery, and the inner diameter of the outlet portion is larger than the inner diameter of the inlet portion. Even if scale due to high-temperature water adheres, there is an effect that it is possible to suppress the flow inhibition of high-temperature water, perform efficient heat exchange, reduce the number of parts, and reduce the cost.

It is a fragmentary sectional view of the different diameter twist tube type heat exchanger concerning an embodiment of the invention. 1 is an overall perspective view of a different diameter twisted tube heat exchanger according to an embodiment of the present invention. It is a figure which shows the manufacture middle state of the water piping of the different diameter torsion pipe | tube heat exchanger which concerns on embodiment of this invention. It is a figure which shows the mandrel used for manufacture of the water piping of the different diameter torsion pipe | tube type heat exchanger which concerns on embodiment of this invention. It is sectional drawing of the inlet_port | entrance part of the different diameter torsion pipe | tube heat exchanger which concerns on embodiment of this invention. It is sectional drawing of the exit part of the different diameter torsion pipe | tube heat exchanger which concerns on embodiment of this invention.

  Hereinafter, an embodiment of a different diameter twisted tube heat exchanger according to the present invention will be described with reference to the drawings.

FIG. 1 is a partial cross-sectional view of a different diameter twisted tube heat exchanger according to an embodiment of the present invention.
The different diameter torsion tube heat exchanger 1 according to this embodiment includes a water pipe 3 provided with a plurality of (for example, three) spiral grooves 2 on the outer periphery, and a spiral groove 2 on the outer periphery of the water pipe 3. And a plurality of refrigerant pipes 4 wound around.
Further, the water pipe 3 has a small diameter part 3a and a large diameter part 3b connected via a tapered part 3c, and is formed as a seamless integral pipe (different diameter pipe). The multiple spiral grooves 2 are formed over substantially the entire length of the water pipe 3. However, in FIG. 1, the spiral groove 2 in the tapered portion 3c is omitted.

  Each refrigerant pipe 4 is fitted into and wound around a spiral groove 2 on the outer periphery of the water pipe 3, and more preferably, the water pipe 3 is made of solder or brazing material (not shown) to improve heat transfer. It is joined with.

  As shown in FIG. 1, the feature of the present invention is that the outlet part of the water pipe 3 is continuously provided with a spiral groove 2 and a plurality of refrigerant pipes 4 on the outer periphery, and the inner diameter of the outlet part. Is larger than the inner diameter of the inlet. By comprising in this way, while being able to improve heat exchange performance, even if a scale adheres to the exit part of the water piping 3, the distribution | circulation of warm water is not inhibited. In addition, since the water pipe 3 is composed of a seamless integral pipe, the heat exchanger can be an inexpensive heat exchanger with a small number of parts.

FIG. 2 is an overall perspective view of the different diameter torsional heat exchanger 1 according to the embodiment of the present invention. As shown in FIG. 2, this different diameter torsional heat exchanger 1 is used by being wound in an elliptical coil shape.
On the inlet side (smaller diameter side) of the water pipe 3, an outlet refrigerant pipe 7 and a refrigerant merging portion 8 connected thereto are provided. The refrigerant merging portion 8 has a plurality of (three in this example) refrigerants. Pipes 4 are connected to each other.
In addition, an inlet refrigerant pipe 5 and a refrigerant distribution section 6 connected to the inlet refrigerant pipe 5 are provided on the outlet side (large diameter side) of the water pipe 3, and the refrigerant distribution section 6 includes a plurality of strips (three in this example). The refrigerant pipes 4 are connected to each other.

As shown by arrows in FIG. 2, water flows in from the small diameter side of the water pipe 3, and flows out as hot water having a higher temperature than the large diameter side.
On the other hand, the refrigerant is sent in such a way as to be opposed to the water flow in order to improve heat exchange efficiency. Therefore, the refrigerant flows in from the inlet refrigerant pipe 5 provided on the large diameter side of the water pipe 3, and flows in a divided manner in each refrigerant pipe 4 in the refrigerant distribution section 6. And the refrigerant | coolant piping which the refrigerant | coolant gas which became high temperature by being compressed with the compressor of the refrigerant circuit which is not shown in figure was wound by the helical groove | channel 2 (it abbreviate | omitted in FIG. 2) of the outer periphery of the water piping 3 of a water circuit (hot-water supply circuit). By flowing through 4 toward the small diameter side of the water pipe 3, heat exchange is efficiently performed between water and the refrigerant. That is, each refrigerant pipe 4 is wound not only on the small diameter part but also on the large diameter part of the water pipe 3 over the entire length of the spiral groove 2, so that the heat transfer area is increased and the efficiency is high. Heat exchange takes place. Further, since the water flowing in the water pipe 3 generates a turbulent flow due to the spiral groove 2, heat exchange is promoted.
The refrigerant that has flowed through each refrigerant pipe 4 is cooled by heat exchange with water, merges at the refrigerant junction 8 on the small diameter side of the water pipe 3, and then flows out from the outlet refrigerant pipe 7 to circulate in the refrigerant circuit. It is like that.

FIG. 3 is a diagram showing a state in the middle of manufacturing the water pipe 3, and FIG. 4 is a diagram showing a mandrel 10 used for manufacturing the water pipe 3.
As shown in FIGS. 3 and 4, the mandrel 10 is formed in different diameters having a small diameter portion 10a and a large diameter portion 10b via a tapered portion 10c.
The water pipe 3 is manufactured by twisting using a mandrel 10 as a core metal. That is, a phosphorous deoxidized copper pipe (element tube) having a length that can be easily brazed or bent is used, for example, about 5 m, and a plurality of ( Here, three dents (dents) are provided at a predetermined circumferential angle. Next, by inserting the above-mentioned different-diameter mandrel 10 into the inner diameter side of the element tube 12, one end of the element tube 12 is expanded over a predetermined length, and a small diameter portion 3a, a tapered portion 3c, and a large diameter portion 3b. A base tube 12 having the following is formed. Then, with the different diameter mandrels 10 inserted, the above three dents of the expanded pipe 12 are chucked and fixed, and the other end of the pipe 12 is rotated to start the dent. Three spiral grooves 2 can be formed on the outer periphery of the blank 12. Thus, by twisting the raw tube 12 using the different diameter mandrel 10, the water pipe 3 having a plurality of spiral grooves 2 on the outer periphery and having one end portion expanded in diameter by a predetermined length is provided. It can be manufactured easily. Further, the water pipe 3 can be easily bent into a coil shape with the refrigerant pipe 4 wound around the spiral groove 2.
The manufacturing method of the water pipe 3 by such a twisting process can manufacture the water pipe 3 more easily than the method of forming a spiral groove by pressing a tool on the outer periphery of the raw pipe.

FIG. 5 shows the inner diameter Di of the small diameter side (inlet part) of the water pipe 3 manufactured by the above twisting process, and FIG. 6 shows the inner diameter Do of the large diameter side (outlet part) of the water pipe 3.
By performing processing so that the inner diameter Do of the outlet portion of the water pipe 3 is 1.1 times or more and 1.25 times or less than the inner diameter Di of the inlet portion, torsion processing by the mandrel 10 can be stably performed. In addition, since the ratio of the peaks and valleys of the spiral groove 2 is not significantly changed, a heat exchange effect due to turbulent flow can be expected even in a high temperature part (water pipe 3 outlet part).

  As described above, the water pipe 3 having a different diameter in which a plurality of spiral grooves 2 are provided on the outer periphery can be formed by twisting using the different diameter mandrel 10. Further, the outlet portion of the water pipe 3 continuously includes the spiral groove 2 and the plurality of refrigerant pipes 4 on the outer periphery, and the inner diameter of the outlet portion is larger than the inner diameter of the inlet portion. Heat can be efficiently exchanged between the water and the refrigerant flowing through the refrigerant pipe 4, and even if a scale adheres to the outlet of the water pipe 3, the flow of hot water is not hindered. In addition, since the water pipe 3 is composed of a seamless integral pipe, the heat exchanger can be an inexpensive heat exchanger with a small number of parts. In other words, since there is no need to newly connect a pipe with a large inner diameter, it can be manufactured inexpensively without increasing the number of processes, and the number of connection points does not increase, so there is no risk of leakage failure and highly reliable heat exchange for hot water supply. Can be manufactured.

  Furthermore, since the spiral groove 2 can be continuously manufactured in the high temperature portion (water pipe 3 outlet portion) where the heat exchange performance is most required, the conventional hot water supply heat exchanger that does not increase the diameter on the high temperature portion side. Compared with the specification, the heat transfer contact area does not decrease, so that the heat exchange performance equal to or higher can be maintained.

  1 heat pipe with different diameters, 2 spiral groove, 3 water pipe, 3a small diameter part, 3b large diameter part, 3c taper part, 4 refrigerant pipe, 5 inlet refrigerant pipe, 6 refrigerant distribution part, 7 outlet refrigerant Piping, 8 Refrigerant merge part, 10 mandrel, 10a small diameter part, 10b large diameter part, 10c taper part, 12 elementary pipe.

Claims (4)

Water pipes with different diameters provided with a plurality of spiral grooves on the outer periphery;
A plurality of refrigerant pipes wound along the spiral groove on the outer circumference of the water pipe,
The outlet portion of the water pipe is continuously provided with the spiral groove and the plurality of refrigerant pipes on the outer periphery, and the inner diameter of the outlet portion is larger than the inner diameter of the inlet portion. Heat exchanger.   2. The different diameter torsion pipe shape according to claim 1, wherein the water pipe has a small diameter portion and a large diameter portion connected via a tapered portion, and is constituted by an integrated pipe having no joint. Heat exchanger.   The inner diameter (Do) of the outlet part of the water pipe is 1.1 times or more and 1.25 times or less of the inner diameter (Di) of the inlet part, The different diameter torsion according to claim 1 or 2 Tube heat exchanger.   Inserting a mandrel with a different diameter having a small diameter part, a taper part, and a large diameter part into the inner diameter side of the raw pipe having a smooth surface to expand one end, and twisting the expanded raw pipe The water pipe having a plurality of spiral grooves formed on the outer periphery thereof is used for the different diameter torsion tube heat exchanger according to any one of claims 1 to 3.

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