JPS6045799B2 - Heat exchanger for water heater - Google Patents
Heat exchanger for water heaterInfo
- Publication number
- JPS6045799B2 JPS6045799B2 JP8988681A JP8988681A JPS6045799B2 JP S6045799 B2 JPS6045799 B2 JP S6045799B2 JP 8988681 A JP8988681 A JP 8988681A JP 8988681 A JP8988681 A JP 8988681A JP S6045799 B2 JPS6045799 B2 JP S6045799B2
- Authority
- JP
- Japan
- Prior art keywords
- heat exchanger
- nickel
- plating
- copper
- water heater
- 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.)
- Expired
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims description 15
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 34
- 238000007747 plating Methods 0.000 claims description 20
- 230000007797 corrosion Effects 0.000 claims description 18
- 238000005260 corrosion Methods 0.000 claims description 18
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 17
- 229910052802 copper Inorganic materials 0.000 claims description 17
- 239000010949 copper Substances 0.000 claims description 17
- 229910052759 nickel Inorganic materials 0.000 claims description 17
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims description 10
- 239000000463 material Substances 0.000 claims description 10
- 229910052751 metal Inorganic materials 0.000 claims description 8
- 239000002184 metal Substances 0.000 claims description 8
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 5
- 238000009713 electroplating Methods 0.000 description 5
- 229910001220 stainless steel Inorganic materials 0.000 description 5
- 239000010935 stainless steel Substances 0.000 description 5
- 238000004381 surface treatment Methods 0.000 description 5
- 229910052725 zinc Inorganic materials 0.000 description 5
- 239000011701 zinc Substances 0.000 description 5
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 239000003973 paint Substances 0.000 description 4
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 3
- 230000005856 abnormality Effects 0.000 description 3
- 229910001369 Brass Inorganic materials 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 2
- 229910000881 Cu alloy Inorganic materials 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000010951 brass Substances 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 239000011651 chromium Substances 0.000 description 2
- 229940116318 copper carbonate Drugs 0.000 description 2
- GEZOTWYUIKXWOA-UHFFFAOYSA-L copper;carbonate Chemical compound [Cu+2].[O-]C([O-])=O GEZOTWYUIKXWOA-UHFFFAOYSA-L 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910021586 Nickel(II) chloride Inorganic materials 0.000 description 1
- 241001311547 Patina Species 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-N carbonic acid Chemical compound OC(O)=O BVKZGUZCCUSVTD-UHFFFAOYSA-N 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000002845 discoloration Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- QMMRZOWCJAIUJA-UHFFFAOYSA-L nickel dichloride Chemical compound Cl[Ni]Cl QMMRZOWCJAIUJA-UHFFFAOYSA-L 0.000 description 1
- LGQLOGILCSXPEA-UHFFFAOYSA-L nickel sulfate Chemical compound [Ni+2].[O-]S([O-])(=O)=O LGQLOGILCSXPEA-UHFFFAOYSA-L 0.000 description 1
- 229910000008 nickel(II) carbonate Inorganic materials 0.000 description 1
- 229910000363 nickel(II) sulfate Inorganic materials 0.000 description 1
- ZULUUIKRFGGGTL-UHFFFAOYSA-L nickel(ii) carbonate Chemical compound [Ni+2].[O-]C([O-])=O ZULUUIKRFGGGTL-UHFFFAOYSA-L 0.000 description 1
- KBJMLQFLOWQJNF-UHFFFAOYSA-N nickel(ii) nitrate Chemical compound [Ni+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O KBJMLQFLOWQJNF-UHFFFAOYSA-N 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- 230000002250 progressing effect Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- XOSXWYQMOYSSKB-LDKJGXKFSA-L water blue Chemical compound CC1=CC(/C(\C(C=C2)=CC=C2NC(C=C2)=CC=C2S([O-])(=O)=O)=C(\C=C2)/C=C/C\2=N\C(C=C2)=CC=C2S([O-])(=O)=O)=CC(S(O)(=O)=O)=C1N.[Na+].[Na+] XOSXWYQMOYSSKB-LDKJGXKFSA-L 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F19/00—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers
- F28F19/02—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers by using coatings, e.g. vitreous or enamel coatings
- F28F19/06—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers by using coatings, e.g. vitreous or enamel coatings of metal
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
Description
【発明の詳細な説明】
本発明は太陽熱集熱器などで加熱された熱媒体を用いて
水を加熱する温水器用熱交換器の耐食性表面処理に関す
るものてある。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to corrosion-resistant surface treatment of a heat exchanger for a water heater that heats water using a heat medium heated by a solar collector or the like.
従来この種の熱交換器材料には熱伝導のよい銅および銅
合金などが使用されてきた。Conventionally, materials such as copper and copper alloys, which have good thermal conductivity, have been used as materials for this type of heat exchanger.
しかし、これらの金属は、水質環境（たとえばｐＨ、導
電率、Ｃｌ−、５０｜−−、ＮＯ３−、ＮＯ２−、遊離
炭素など）により、緑青、脱亜鉛、隙間腐食などの腐食
が発生し、短期間に穴があいてしまう欠点があつた。こ
れらの耐食性を向上させるために、従来は金属材料の表
面処理としてメッキ膜の形成、例えばニッケル、クロム
などの電気メッキ、アルミニウム、亜鉛などの溶融メッ
キ、およびシリコン系塗料などの塗膜形成が検討されて
きた。しかし、ニッケル、クロムなどの電気メッキはピ
ンホール部からの腐食がさけられず、すぐ素材が露出し
てしまうのでメッキの効果が得られなかつた。特に銅に
ニッケルなどを電気メッキした熱交換器を遊離炭酸の多
い水で使用すると、まずピンホール部の銅が遊離炭酸と
次式のように反応して塩基性炭酸銅になり、ＣＵ＋Ｃ０
２＋Ｈ２Ｏ→ＣＵＣ０ａ−ＣＵ（ＯＨ）２さらにメッキ
下側の銅まで腐食が進行して、ついにはメッキが剥離し
てしまう。However, these metals suffer from corrosion such as patina, dezincification, crevice corrosion, etc. depending on the water quality environment (e.g. pH, conductivity, Cl-, 50|--, NO3-, NO2-, free carbon, etc.). There was a drawback that holes appeared in a short period of time. In order to improve these corrosion resistances, conventional methods of surface treatment for metal materials include forming plating films, such as electroplating with nickel and chromium, hot-dip plating with aluminum and zinc, and forming coatings with silicon-based paints. It has been. However, electroplating of nickel, chromium, etc. cannot avoid corrosion from the pinholes, and the material is exposed immediately, so the plating effect cannot be obtained. In particular, when a heat exchanger made of copper electroplated with nickel or the like is used with water containing a large amount of free carbonate, the copper in the pinholes first reacts with the free carbonate as shown in the following equation and becomes basic copper carbonate, CU+C0
2+H2O→CUC0a-CU(OH)2 Corrosion further progresses to the copper underneath the plating, and the plating eventually peels off.
このような状態になると熱交換器の表面全体にグリーン
の塩基性炭酸銅が生成して給湯水が青くなつたり、つい
には穴があいてしまう欠点があつた。また、銅合金、例
えば黄銅にニッケルなどを電気メッキした熱交換器を導
電率のやゝ高い水の中で使用すると、ピンホール部の黄
銅中の亜鉛は電位が銅に比較して卑であるため、亜鉛の
み溶出してしまい脱亜鉛現象をおこしてしまう欠点があ
つた。Under such conditions, green basic copper carbonate would form on the entire surface of the heat exchanger, turning the hot water blue and eventually causing holes. Additionally, when a heat exchanger made of a copper alloy, such as brass, electroplated with nickel, is used in water with relatively high conductivity, the potential of the zinc in the brass in the pinhole area is less base than that of the copper. Therefore, there was a drawback that only zinc was eluted and a dezincing phenomenon occurred.
さらに、亜鉛などの溶融メッキした銅熱交換器は表面の
亜鉛が犠牲陽極の働きをして、溶解してしまい、すぐ素
材の銅が露出してしまうのでメッキの効果が得られなか
つた。シリコン系塗料などの塗布は、塗膜にさけられな
いピンホールに起因して、腐食が発生し塗膜のフクレ、
剥離が発生して、さらに激しい腐食へと進行している。Furthermore, with hot-dip plated copper heat exchangers, the zinc on the surface acts as a sacrificial anode and melts, immediately exposing the copper material, making the plating ineffective. When applying silicone-based paints, corrosion occurs due to unavoidable pinholes in the paint film, causing blistering and blistering of the paint film.
Peeling has occurred, progressing to even more severe corrosion.
そこで単に、耐食性の面からのみ考えると、耐食性にす
ぐれた高価な金属材料、たとえば白金、金、ステンレス
などを使用すれば耐食性は向上するように考えられるが
、白金、金などは経済性、機械加工性などの面から実用
性に欠けると考えられる。Therefore, if we consider only from the perspective of corrosion resistance, it is thought that corrosion resistance can be improved by using expensive metal materials with excellent corrosion resistance, such as platinum, gold, and stainless steel. It is thought that it lacks practicality in terms of workability and other aspects.
また、ステンレスは機械加工性が欠けるとともに、応力
腐食割れ、すきま腐食、孔腐などが懸念され、これらの
課題を解決して使用することは容易でない。本発明は、
これらの欠点を除去したもので、熱交換器素材の表面に
素材よりイオン化傾向の大きい金属をメッキし、さらに
該メッキ金属よりイオン化傾向の小さい金属をメッキし
て２重のメッキ層を形成して、従来の欠点を除去したも
のを提供する。In addition, stainless steel lacks machinability, and there are concerns about stress corrosion cracking, crevice corrosion, pitting rot, etc., and it is not easy to solve these problems and use it. The present invention
These drawbacks have been removed by plating the surface of the heat exchanger material with a metal that has a greater ionization tendency than the material, and then plating a metal that has a smaller ionization tendency than the plated metal to form a double plating layer. , which eliminates the drawbacks of the conventional technology.
以下図面を参照しながら詳述する。本発明の１実施例を
図に示す。A detailed description will be given below with reference to the drawings. An embodiment of the invention is shown in the figure.
−同図のように熱交換器素材として銅１および、それを
固定するフランジ部４の表面に銅よりイオン化傾向の大
きいニッケルを電気メッキしてニッケル層−２を形成；
し、さらに該ニッケルよりもイオン化傾向の小さく、し
かも素材の銅よりイオン化傾向の大きいスズを電気メッ
キ３して２重のメッキ層を形成したものである。このよ
うに、ニッケルメッキの上にニッケルよりイオン化傾向
の小さいスズをメッキ２することにより次の効果が得ら
れる。（１）スズは前述の亜鉛のようにイオン化傾向が
大でなく、上述のようにニッケルより小であるから溶解
しにくい。- As shown in the figure, a nickel layer 2 is formed by electroplating nickel, which has a higher ionization tendency than copper, on the surface of copper 1 as a heat exchanger material and the flange part 4 that fixes it;
Furthermore, tin, which has a smaller ionization tendency than the nickel and a greater ionization tendency than the copper material, is electroplated to form a double plating layer. In this way, the following effects can be obtained by plating tin, which has a smaller ionization tendency than nickel, on nickel plating. (1) Tin does not have a strong ionization tendency like zinc, but is smaller than nickel as mentioned above, so it is difficult to dissolve.
（２）スズはメッキしやすい金属であるのでピンホこー
ルができにくく、下地ニッケルメッキのピンホールをカ
バーしてくれる。(2) Tin is a metal that is easy to plate, so pinholes are less likely to form, and it covers pinholes in the underlying nickel plating.
（３）ニッケルは水に含まれているＳＯ４−、ＮＯ３−
、Ｃ１八ＮＯ２−、遊離炭酸などと反応して、硫酸ニツ
ケ、硝酸ニッケル、塩化二ツケ３ル、炭酸ニッケルなど
になつて腐食されやすいが、スズは比較的水質環境には
強いのて表面にスズメッキ層があると水の中ての耐久性
は強くなる。(3) Nickel is contained in water SO4-, NO3-
, C18NO2-, free carbonic acid, etc., forming nickel sulfate, nickel nitrate, nickel chloride, nickel carbonate, etc., and is easily corroded, but tin is relatively resistant to aqueous environments and does not adhere to the surface. The presence of a tin plating layer increases durability in water.
上記構成の本熱交換器は前述のように各種類の４過酷な
水質環境下で使用するため、各種の腐食試験を通して、
その効果を確認した。As mentioned above, this heat exchanger with the above configuration is used in various types of harsh water quality environments, so it has been tested through various corrosion tests.
We confirmed its effectiveness.
（１）塩水溶液試験
各種表面処理を行つた銅板およびステンレス板を８５℃
の塩水溶液（Ｃ１一濃度：５００ｐｐｍ）中に５０ＣＢ
！ｆ間侵漬した結果を第１表に示す。(1) Salt aqueous solution test Copper plates and stainless steel plates with various surface treatments were tested at 85°C.
50CB in a salt aqueous solution (C1 concentration: 500 ppm)
! Table 1 shows the results of immersion for f.
この結果より、銅の表面にニッケルとスズを電気メッキ
法で２重に形成することにより全く異常のないことを確
認した。（２）硫酸溶液試験
上記の各種表面処理を行つた銅板およびステンレス板を
８５℃の硫酸溶液（ＳＯ，一濃度：１００ｐｐｍ）中に
５００時間浸漬した結果は、ほＳ゛第１表の結果と同じ
であつたが、銅にＮｉＯ．５ミクン以下、Ｓｎ２ミクロ
ン以下のメッキ試料も数個所に黒い変色が見られた。From this result, it was confirmed that there was no abnormality at all when nickel and tin were formed twice on the copper surface by electroplating. (2) Sulfuric acid solution test The results of immersing the copper plates and stainless steel plates that had been subjected to the various surface treatments mentioned above in a sulfuric acid solution (SO, concentration: 100 ppm) at 85°C for 500 hours are similar to those shown in Table 1. It was the same, but with NiO. Black discoloration was observed in several places on the plated samples of 5 microns or less and Sn of 2 microns or less.
しかし、銅にＮｉＯ．５ミクロン以上、Ｓｎ２ミクロン
以上のメッキ試料は全く異常のないことを確かめた。However, NiO. It was confirmed that there were no abnormalities in the plated samples of 5 microns or more and Sn of 2 microns or more.
（３） 発露試験
実際の使用環境因子の腐食促進試験を相定して７０℃、
湿度１００％の中をＣＯ２５％、ＮＯ２ｌＯＰＰｍ，．
ＳＯ２５ＰＰｍの雰囲気にして、各種表面処理を行つた
銅板およびステンレス板を入れて、発露、乾燥をくり返
して腐食試験を行つた結果を第２表に示す。(3) Dew test: 70°C, in accordance with the corrosion acceleration test of actual usage environmental factors.
In 100% humidity, CO25%, NO2lOPPm, .
Table 2 shows the results of a corrosion test in which a copper plate and a stainless steel plate that had been subjected to various surface treatments were placed in an atmosphere of SO25PPm, and dew was repeatedly exposed and dried.
第２表より、水質環境（たとえば遊離炭酸、ＮＯ２−、
ＮＯ３−、ＳＯ４一つのきびしい条件でも銅の表面にニ
ッケルとスズを電気メッキ法で２重に形成することによ
り全く異常のないことを確認した。以上のごとく、本構
成の熱交換器は、あらゆる水質環境による耐食性が極め
て優れたものであり水の中で使用する場合は非常に実用
的てある。From Table 2, water quality environment (e.g. free carbonate, NO2-,
It was confirmed that there was no abnormality even under the severe conditions of NO3- and SO4 by forming nickel and tin in double layers on the copper surface by electroplating. As described above, the heat exchanger of this configuration has extremely excellent corrosion resistance in all water environments, and is very practical when used in water.
Claims (1)
キし、さらにその上にメッキした金属よりイオン化傾向
の小さい金属をメッキして、２重のメッキ層を形成した
ことを特徴とする温水器用熱交換器。 ２ 素材銅にニッケルをメッキし、さらにその上に耐食
性に優れたスズをメッキして２重のメッキ層を形成した
ことを特徴とする特許請求の範囲第１項記載の温水器用
熱交換器。 ３ 銅にニッケルを０．５ミクロン以上メッキし、さら
にその上にスズを２ミクロン以上メッキして２層を形成
したことを特徴とする特許請求の範囲第２項記載の温水
器用熱交換器。[Claims] 1. A double plating layer is formed by plating a metal with a greater ionization tendency than the heat exchanger material and then plating a metal with a smaller ionization tendency than the plated metal. A heat exchanger for water heaters featuring: 2. The heat exchanger for a water heater according to claim 1, characterized in that a double plating layer is formed by plating copper material with nickel and further plating tin with excellent corrosion resistance thereon. 3. The heat exchanger for a water heater according to claim 2, characterized in that copper is plated with nickel to a thickness of 0.5 microns or more, and tin is further plated on top of the nickel to a thickness of 2 microns or more to form two layers.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8988681A JPS6045799B2 (en) | 1981-06-11 | 1981-06-11 | Heat exchanger for water heater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8988681A JPS6045799B2 (en) | 1981-06-11 | 1981-06-11 | Heat exchanger for water heater |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57204799A JPS57204799A (en) | 1982-12-15 |
| JPS6045799B2 true JPS6045799B2 (en) | 1985-10-12 |
Family
ID=13983233
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8988681A Expired JPS6045799B2 (en) | 1981-06-11 | 1981-06-11 | Heat exchanger for water heater |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6045799B2 (en) |
-
1981
- 1981-06-11 JP JP8988681A patent/JPS6045799B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57204799A (en) | 1982-12-15 |
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