JPH09257384A - Welded tube with inner surface groove of air-conditioning heat exchanger - Google Patents
Welded tube with inner surface groove of air-conditioning heat exchangerInfo
- Publication number
- JPH09257384A JPH09257384A JP9333796A JP9333796A JPH09257384A JP H09257384 A JPH09257384 A JP H09257384A JP 9333796 A JP9333796 A JP 9333796A JP 9333796 A JP9333796 A JP 9333796A JP H09257384 A JPH09257384 A JP H09257384A
- Authority
- JP
- Japan
- Prior art keywords
- groove bottom
- vertical groove
- inclined groove
- bottom portion
- width direction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
- Details Of Heat-Exchange And Heat-Transfer (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、内部に気液二相状
態の冷媒が流通する空調用熱交換器の内面溝付き溶接管
に係り、薄い金属製条材の内面側に多数の突条及び溝を
並列させ、それを管状に塑性変形して継目を溶接した溶
接管に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grooved welded pipe of an air-conditioning heat exchanger in which a gas-liquid two-phase refrigerant flows, and a large number of ridges are formed on the inner surface of a thin metal strip. Also, the present invention relates to a welded pipe in which grooves are juxtaposed and the pipe is plastically deformed to weld a seam.
【０００２】[0002]
【従来の技術】空調用熱交換器は、冷媒が気液二相状態
で流通する管を有し、その管内面に冷媒攪拌用の多数の
溝及び突条を形成したものが提案されている。例えば、
薄い金属製条材の表面に傾斜する溝を一方向にのみ設
け、それを管状に丸めその継目を溶接固定したもの或い
は、多数の傾斜溝を条材の中心線に対し対称に形成し、
それを管状に丸めて溶接固定してもの等が知られてい
る。2. Description of the Related Art It has been proposed that an air conditioning heat exchanger has a pipe through which a refrigerant flows in a gas-liquid two-phase state, and a large number of grooves and projections for stirring the refrigerant are formed on the inner surface of the pipe. . For example,
A slanting groove is provided on the surface of a thin metal strip only in one direction, and it is rolled into a tubular shape and its seam is welded and fixed, or a number of slanted grooves are formed symmetrically with respect to the center line of the strip,
It is known that it is rolled into a tubular shape and fixed by welding.
【０００３】[0003]
【発明が解決しようとする課題】内面溝付き管は、溝な
し管に比べて冷媒側の熱伝達率を向上することが認めら
れているが、さらに熱伝達率の良いものが求められてい
た。そこで本発明者は、各種実験の結果、冷媒側熱伝達
率を向上する方法として、傾斜溝に加えてさらに管の軸
線に平行な縦溝が有効であることを見出し、さらにはそ
の縦溝と傾斜溝との境目のおける冷媒の挙動が熱伝達率
に大きな影響を与えることを見出し、その知見に基づい
で本発明を完成してものである。It has been recognized that the inner grooved tube improves the heat transfer coefficient on the refrigerant side as compared with the non-grooved tube, but a tube having a higher heat transfer coefficient has been required. . Therefore, the present inventor has found that, as a result of various experiments, in addition to the inclined groove, a vertical groove parallel to the axis of the pipe is effective as a method for improving the heat transfer coefficient on the refrigerant side. The present invention has been completed based on the finding that the behavior of the refrigerant at the boundary with the inclined groove has a great influence on the heat transfer coefficient.
【０００４】[0004]
【課題を解決するための手段】本発明の空調用熱交換器
の内面溝付き溶接管は、薄い金属製条材の長手方向に平
行で且つ幅方向に互いに離間して内面に形成された複数
の縦溝底部１と、夫々の縦溝１間で前記長手方向に対し
て斜方向に突条部２と傾斜溝底部３とが交互に多数並列
された複数の傾斜溝群４と、を具備し、前記縦溝底部１
が前記傾斜溝底部３よりも浅く形成され、その縦溝底部
１の幅方向側端に僅かに立ち上げられた側壁部５と、そ
の側壁部５上縁から前記傾斜溝群の幅方向の中央部に向
けて先下がりとなるスロープ面６とが形成され、前記金
属製条材が幅方向に横断面円形に湾曲されて、その継目
が液密に溶接固定されてなるものである。次に、第２の
本発明は、上記構成において、前記縦溝底部１の幅方向
両側に前記側壁部５が存在し、前記縦溝底部１を境とす
る隣り合う前記傾斜溝群４の傾斜方向が互いに異なって
ハの字または逆ハの字状に形成されたものである。ま
た、第３の本発明は、上記第１の発明の構成において、
前記縦溝底部１の幅方向両側に前記側壁部５が存在し、
前記縦溝底部１を境とする隣り合う前記傾斜溝群４の傾
斜方向が同一に形成されたものである。The welded pipe with groove on the inner surface of the heat exchanger for air-conditioning according to the present invention is formed on the inner surface parallel to the longitudinal direction of the thin metal strip and spaced from each other in the width direction. Vertical groove bottom portions 1 and a plurality of inclined groove groups 4 in which a large number of ridges 2 and inclined groove bottom portions 3 are alternately arranged in parallel with each other in the oblique direction with respect to the longitudinal direction. Then, the vertical groove bottom 1
Is formed to be shallower than the inclined groove bottom portion 3, and is slightly raised at the widthwise side end of the vertical groove bottom portion 1, and the center of the inclined groove group in the width direction from the upper edge of the side wall portion 5. The sloped surface 6 is formed so as to descend toward the end, the metal strip is curved in a transverse cross section in the width direction, and the seam is welded and fixed in a liquid-tight manner. Next, 2nd this invention WHEREIN: In the said structure, the said side wall part 5 exists in the width direction both sides of the said vertical groove bottom part 1, and the inclination of the said adjacent inclined groove group 4 which makes the said vertical groove bottom part 1 a boundary. The directions are different from each other and are formed in a V shape or an inverted V shape. A third aspect of the invention is based on the configuration of the first aspect of the invention.
The side wall portions 5 are present on both sides in the width direction of the vertical groove bottom portion 1,
The slanting directions of the slanting groove groups 4 adjacent to each other with the vertical groove bottom portion 1 as a boundary are the same.
【０００５】[0005]
【発明の実施の形態】次に、本発明の実施の態様につき
説明する。図１は本発明の第１の実施の態様を示す溶接
管８の一部展開図、図２は図１のII−II矢視端面図、図
３は同斜視略図である。この溶接管８は、銅板の条材に
予め傾斜溝群４，４ａ及び縦溝底部１を形成し、次いで
次工程で条材を次第に断面円形に形成し、その継目を電
気溶接により溶接固定するものである。そして、管内面
には複数の縦溝底部１が等間隔に周方向に互いに離間し
て配置され、その縦溝底部１を挟んで両側に互いに逆向
きに傾斜した傾斜溝群４，４ａが形成されている。この
縦溝底部１の溝の深さは図２及び図３に示す如く傾斜溝
群４の傾斜溝底部３よりも浅く形成されている。多数の
傾斜溝底部３の深さは管の平均肉厚の 0.3倍〜 0.7倍で
ある。そして、縦溝底部１の深さは傾斜溝底部３の深さ
の 3/4〜 1/2程度である。また、管の平均肉厚は 0.25m
m 〜 0.5mm程である。そして、縦溝底部１の幅方向両側
には0.03〜0.05mm程の側壁部５が立ち上げられ、その側
壁部５の先端から傾斜溝群４及び傾斜溝群４ａの幅方向
中心部に向けて先下がりとなるスロープ面６が形成され
ている。このスロープ面６の傾斜角度は、10度前後であ
る。また、図４は本発明の他の実施の形態を示し、この
例が図１のそれと異なることは、縦溝底部１を挟んでそ
の両側に形成された一方の傾斜溝群４と他方の傾斜溝群
４ａの傾斜方向が全く同一である点のみである。BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described. FIG. 1 is a partially developed view of a welded pipe 8 showing a first embodiment of the present invention, FIG. 2 is an end view taken along the line II-II of FIG. 1, and FIG. 3 is a schematic perspective view of the same. In this welded pipe 8, the inclined groove groups 4 and 4a and the vertical groove bottom portion 1 are formed in advance on the strip material of the copper plate, then the strip material is gradually formed into a circular cross section in the next step, and the seam is welded and fixed by electric welding. It is a thing. A plurality of vertical groove bottom portions 1 are arranged at equal intervals on the inner surface of the pipe in the circumferential direction, and inclined groove groups 4 and 4a are formed on both sides of the vertical groove bottom portion 1 so as to be opposite to each other. Has been done. The depth of the vertical groove bottom portion 1 is formed to be shallower than that of the inclined groove bottom portion 3 of the inclined groove group 4 as shown in FIGS. The depth of the bottoms 3 of the plurality of inclined grooves is 0.3 to 0.7 times the average wall thickness of the pipe. The depth of the vertical groove bottom portion 1 is about 3/4 to 1/2 of the depth of the inclined groove bottom portion 3. The average wall thickness of the pipe is 0.25m.
It is about m to 0.5 mm. Then, side walls 5 of about 0.03 to 0.05 mm are erected on both sides of the vertical groove bottom 1 in the width direction, and from the tips of the side walls 5 toward the center in the width direction of the inclined groove group 4 and the inclined groove group 4a. The slope surface 6 is formed so as to descend downward. The slope angle of this slope surface 6 is around 10 degrees. FIG. 4 shows another embodiment of the present invention. This example differs from that of FIG. 1 in that one inclined groove group 4 formed on both sides of the vertical groove bottom portion 1 and the other inclined groove group 4 are formed. The only difference is that the inclination directions of the groove groups 4a are exactly the same.
【０００６】[0006]
【実施例】次に、本発明の一実施例につき説明すると、
外径が７mmで平均肉厚が0.31mmのヒートポンプ型空調用
熱交換器の冷媒管において、傾斜溝群４（４ａを含む）
のリード角α（図１）は１８度で、その傾斜溝底部３の
深さｈ２＝0.17mm（図２）であり、図１に示す如く周方
向に６分割され、夫々の傾斜溝群４，４ａは互いに逆向
きに配置されている。そして軸に直角な横断面におい
て、傾斜溝群４の傾斜溝底部３の数は４８本である。ま
た、互いに逆向きに配置された傾斜溝群４，４ａの境目
には縦溝底部１が形成されている。この縦溝底部１は、
その幅Ｗ１が 0.4mmであり、外表面からの厚みｈ３が0.
28mmである。また、側壁部５の高さh4は0.03〜0.05mmで
ある。さらに、スロープ面６の幅は 0.5mmである。EXAMPLE Next, an example of the present invention will be described.
Inclined groove group 4 (including 4a) in a refrigerant tube of a heat pump type air conditioner heat exchanger having an outer diameter of 7 mm and an average thickness of 0.31 mm
Has a lead angle .alpha. (FIG. 1) of 18 degrees, and the depth h2 of the inclined groove bottom portion 3 is 0.17 mm (FIG. 2), and is divided into 6 in the circumferential direction as shown in FIG. , 4a are arranged opposite to each other. The number of the inclined groove bottom portions 3 of the inclined groove group 4 is 48 in the transverse section perpendicular to the axis. Further, a vertical groove bottom portion 1 is formed at the boundary between the inclined groove groups 4 and 4a arranged in opposite directions. This flute bottom 1 is
The width W1 is 0.4 mm and the thickness h3 from the outer surface is 0.
28 mm. The height h4 of the side wall portion 5 is 0.03 to 0.05 mm. Further, the width of the slope surface 6 is 0.5 mm.
【０００７】[0007]
【交換熱量の比較】次に、図１における実施例の溶接管
と、従来型の溶接管で縦溝底部１が存在せず傾斜溝群
４，４ａのみが同一条件で形成された溶接管との比較実
験をしてところ、図１に示す本発明の溶接管は凝縮器及
び蒸発器のいずれにおいても熱伝達率が 5〜 7％向上し
た。そのときの条件は次の通りである。上記実施例の溶
接管をコンデンサーとしての熱交換器に用いた条件は、
入口空気の乾球温度が35度で湿球温度が24度である。ま
たコンデンサの入口圧は20.8Kg／cm2 Ｇであり、過熱度
は25deg 、過冷却度は５deg 、ファン流速は1.0m／s 、
冷媒流量は50Kg／hrとした。そして、従来の溶接管の交
換熱量を 100としたとき、図１に示す溶接管は複数回の
実験において 105〜 107となった。[Comparison of heat exchange amount] Next, the welded pipe of the embodiment shown in FIG. 1 and the welded pipe of the conventional welded pipe in which the vertical groove bottom portion 1 does not exist and only the inclined groove groups 4 and 4a are formed under the same condition. As a result of a comparative experiment, the heat transfer coefficient of the welded pipe of the present invention shown in FIG. 1 was improved by 5 to 7% in both the condenser and the evaporator. The conditions at that time are as follows. The conditions of using the welded pipe of the above example in the heat exchanger as the condenser are:
The dry-bulb temperature of the inlet air is 35 degrees and the wet-bulb temperature is 24 degrees. The inlet pressure of the condenser is 20.8Kg / cm 2 G, the degree of superheat is 25deg, the degree of supercooling is 5deg, and the fan flow velocity is 1.0m / s.
The refrigerant flow rate was 50 kg / hr. When the heat exchange amount of the conventional welded pipe was 100, the welded pipe shown in FIG. 1 was 105 to 107 in a plurality of experiments.
【０００８】次に本発明の溶接管及び従来型溶接管を夫
々エバポレーターとしての熱交換器の性能試験を行っ
た。このときの実験条件は入口空気の乾球温度が27度で
湿球温度が19度である。また、エバポレータ出口圧は管
内圧は5.4Kg ／cm2 Ｇであり、過熱度は５deg、過冷却
度は５deg 、ファン流速は0.8m／s 、冷媒流量は70Kg／
hrである。そして、従来の溶接管と 100としたときの熱
交換量は、本発明の図１における実施例の溶接管が 106
〜 107であった。次に、比較例として図１〜図３に示す
溝付き溶接管において、スロープ６を全く設けず、その
部分に傾斜溝部３をそのまま延長した溝付き管を用意
し、それを前記同様に実験したところ、本発明の溝付き
溶接管より２〜３％熱交換量が悪くなった。このように
本発明の溶接管は、何れの比較例よりも熱交換量が向上
することが実験によりわかった。その理由は明確ではな
いが、後述する発明の作用の如く推測できる。Next, the welded pipe of the present invention and the conventional welded pipe were each subjected to a performance test of a heat exchanger as an evaporator. The experimental conditions at this time were that the inlet air had a dry-bulb temperature of 27 degrees and the wet-bulb temperature was 19 degrees. The outlet pressure of the evaporator is 5.4 kg / cm 2 G in the pipe, the superheat degree is 5 deg, the supercooling degree is 5 deg, the fan flow velocity is 0.8 m / s, and the refrigerant flow rate is 70 kg / cm.
hr. The heat exchange amount when the conventional welded pipe is set to 100 is 106 in the welded pipe of the embodiment in FIG. 1 of the present invention.
It was ~ 107. Next, as a comparative example, in the welded tube with grooves shown in FIGS. 1 to 3, a grooved tube was prepared in which the slope 6 was not provided at all, and the inclined groove portion 3 was extended as it was, and it was tested in the same manner as above. However, the heat exchange amount was 2-3% worse than that of the grooved welded pipe of the present invention. As described above, it has been experimentally found that the welded pipe of the present invention has a higher heat exchange amount than any of the comparative examples. The reason for this is not clear, but it can be inferred from the action of the invention described later.
【０００９】[0009]
【発明の作用・効果】本発明の空調用熱交換器の内面溝
付き溶接管は、複数の傾斜溝群４の間に縦溝底部１が設
けられ、縦溝底部１の幅方向側縁に僅かに立ち上げられ
た側壁部５と、その側壁部５上縁から傾斜溝群４の幅方
向中央部に向けて先下がりとなるスロープ面６を設けた
から、気液二相状態で管内を流通する冷媒は、その液相
部分が傾斜溝群４に沿って移動するとき、スロープ面６
によって冷媒を管の中心側に、かき上げ、それを液相の
存在しない乾いた突条２表面に散布して、蒸発を促し熱
交換を促進させる効果がある。すなわち、蒸発器として
の性能を向上し得る。また、本溶接管が凝縮器としての
熱交換器を構成する場合には、傾斜溝群４の傾斜溝底部
３に沿って比較的ゆっくり移動してきた凝縮液はスロー
プ面６を超えて円滑に縦溝底部１の導かれ、軸線方向に
円滑に排除される。そして、それが傾斜溝底部３側に逆
流することを側壁の立ち上がり面により防止できる。そ
のため、傾斜溝群４が凝縮液の皮膜で覆われることを可
能な限り防止し、それにより凝縮性能を向上し得る。即
ち、本溶接管は凝縮器としてもその熱伝達率を向上する
ことができる。また、縦溝底部１は傾斜溝底部３よりも
浅く形成されているから、薄い金属製条材を管状の塑性
変形する際に、縦溝底部１の部分が他の部分より大きく
変形することを防止して、管外周が多角形になることを
防ぎ、真円度の高い信頼性の高い溶接管を提供できる。In the welded pipe with the inner groove of the heat exchanger for air conditioning of the present invention, the vertical groove bottom portion 1 is provided between the plurality of inclined groove groups 4, and the widthwise side edge of the vertical groove bottom portion 1 is provided. Since the side wall portion 5 that is slightly raised and the slope surface 6 that descends from the upper edge of the side wall portion 5 toward the widthwise central portion of the inclined groove group 4 are provided, the gas flows through the pipe in a two-phase gas-liquid state. When the liquid phase part of the cooling medium moves along the inclined groove group 4, the slope surface 6
By this, the refrigerant is scooped up toward the center of the pipe, and is sprayed on the surface of the dry ridge 2 where the liquid phase does not exist, which has the effect of promoting evaporation and promoting heat exchange. That is, the performance as an evaporator can be improved. Further, when the main welded pipe constitutes a heat exchanger as a condenser, the condensate that has moved relatively slowly along the inclined groove bottom portion 3 of the inclined groove group 4 smoothly extends vertically beyond the slope surface 6. The groove bottom 1 is guided and smoothly removed in the axial direction. Then, it can be prevented by the rising surface of the side wall that it will flow backward to the inclined groove bottom 3 side. Therefore, it is possible to prevent the inclined groove group 4 from being covered with the film of the condensate as much as possible, thereby improving the condensing performance. That is, the present welded tube can improve the heat transfer coefficient even as a condenser. Further, since the vertical groove bottom portion 1 is formed shallower than the inclined groove bottom portion 3, when the thin metal strip is plastically deformed into a tubular shape, the portion of the vertical groove bottom portion 1 is deformed more than other portions. It is possible to prevent the outer circumference of the pipe from becoming polygonal, and to provide a highly reliable welded pipe with high roundness.
【図１】本発明の空調用熱交換器の内面溝付き溶接管の
一部展開正面図。FIG. 1 is a partially developed front view of a welded tube with an inner groove of a heat exchanger for air conditioning of the present invention.
【図２】図１のII−II矢視端面図。FIG. 2 is an end view taken along the line II-II of FIG.
【図３】同要部拡大斜視図。FIG. 3 is an enlarged perspective view of the relevant part.
【図４】本発明の第２の例を示す溶接管の一部展開正面
図。FIG. 4 is a partially developed front view of a welded pipe showing a second example of the present invention.
１ 縦溝底部 ２ 突条 ３ 傾斜溝底部 ４，４ａ 傾斜溝群 ５ 側壁部 ６ スロープ面 ７ 溶接部 ８ 溶接管 1 Vertical groove bottom 2 Ridge 3 Inclined groove bottom 4, 4a Inclined groove group 5 Side wall part 6 Slope surface 7 Welded part 8 Welded pipe
Claims (3)
幅方向に互いに離間して内面に形成された複数の縦溝底
部１と、 夫々の縦溝底部１間で前記長手方向に対して斜め方向に
突条部２と傾斜溝底部３とが交互に多数並列された複数
の傾斜溝群４と、 を具備し、前記縦溝底部１が前記傾斜溝底部３よりも浅
く形成され、 その縦溝底部１の幅方向側端に僅かに立ち上げられた側
壁部５と、その側壁部５の上縁から前記傾斜溝群４の幅
方向の中央部に向けて先下がりとなるスロープ面６が形
成され、 前記金属製条材が幅方向に横断面円形に湾曲されて、そ
の継目が液密に溶接固定されてなる空調用熱交換器の内
面溝付き溶接管。1. A plurality of vertical groove bottom portions 1 formed on an inner surface of a thin metal strip parallel to the longitudinal direction and spaced from each other in the width direction, and between the vertical groove bottom portions 1 with respect to the longitudinal direction. A plurality of inclined groove groups 4 in which a large number of ridges 2 and inclined groove bottoms 3 are alternately arranged in parallel, and the vertical groove bottoms 1 are formed to be shallower than the inclined groove bottoms 3. A side wall portion 5 slightly raised at the widthwise side end of the vertical groove bottom portion 1 and a slope surface which is lowered from the upper edge of the side wall portion 5 toward the center portion in the width direction of the inclined groove group 4. 6 is formed, and the metal strip is curved in a circular cross-section in the width direction, and the seam of the metal strip is welded and fixed in a liquid-tight manner.
方向両側に前記側壁部５が存在し、前記縦溝底部１を境
とする隣り合う前記傾斜溝群４の傾斜方向が互いに異な
ってハの字または逆ハの字状に形成された溶接管。2. The side wall portions 5 are present on both sides of the vertical groove bottom portion 1 in the width direction, and the inclination directions of the adjacent inclined groove groups 4 with the vertical groove bottom portion 1 as a boundary are different from each other. Welded pipe that is formed in a V shape or an inverted V shape.
方向両側に前記側壁部５が存在し、前記縦溝底部１を境
とする隣り合う前記傾斜溝群４の傾斜方向が同一に形成
された溶接管。3. The side wall portions 5 are provided on both sides of the vertical groove bottom portion 1 in the width direction, and the inclination directions of the adjacent inclined groove groups 4 with the vertical groove bottom portion 1 as a boundary are the same. Formed welded pipe.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP09333796A JP3541334B2 (en) | 1996-03-22 | 1996-03-22 | Welded pipe with internal groove for heat exchanger for air conditioning |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP09333796A JP3541334B2 (en) | 1996-03-22 | 1996-03-22 | Welded pipe with internal groove for heat exchanger for air conditioning |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH09257384A true JPH09257384A (en) | 1997-10-03 |
| JP3541334B2 JP3541334B2 (en) | 2004-07-07 |
Family
ID=14079462
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP09333796A Expired - Fee Related JP3541334B2 (en) | 1996-03-22 | 1996-03-22 | Welded pipe with internal groove for heat exchanger for air conditioning |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3541334B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006514733A (en) * | 2003-05-10 | 2006-05-11 | チンファ ユニバーシティ | Enhanced heat exchanger tube with discontinuous bi-directionally inclined internal ribs |
-
1996
- 1996-03-22 JP JP09333796A patent/JP3541334B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006514733A (en) * | 2003-05-10 | 2006-05-11 | チンファ ユニバーシティ | Enhanced heat exchanger tube with discontinuous bi-directionally inclined internal ribs |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3541334B2 (en) | 2004-07-07 |
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