JPH06316945A - Method for plating cast iron manhole cover - Google Patents
Method for plating cast iron manhole coverInfo
- Publication number
- JPH06316945A JPH06316945A JP5121921A JP12192193A JPH06316945A JP H06316945 A JPH06316945 A JP H06316945A JP 5121921 A JP5121921 A JP 5121921A JP 12192193 A JP12192193 A JP 12192193A JP H06316945 A JPH06316945 A JP H06316945A
- Authority
- JP
- Japan
- Prior art keywords
- plating
- manhole cover
- cover
- zinc
- cast iron
- 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
- Underground Structures, Protecting, Testing And Restoring Foundations (AREA)
- Coating With Molten Metal (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、鋳鉄製のマンホール蓋
のめっき方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for plating a cast iron manhole cover.
【０００２】[0002]
【従来の技術】路面に敷設されるマンホール蓋は、一般
に鋳造をした表面状態のままで敷設しているが、一部に
防食性を持たせるために、鋳造後の表面を清浄処理し、
タールに浸漬してタール皮膜を表面に形成したものがあ
る。2. Description of the Related Art A manhole cover laid on a road surface is generally laid in the state of a cast surface, but in order to have corrosion resistance on a part, the surface after casting is cleaned,
There is one in which a tar film is formed on the surface by immersing it in tar.
【０００３】[0003]
【発明が解決しようとする課題】上記タール皮膜は密着
性が弱く短時間ではがれ易い。とくに塩害を受けやすい
海岸近くや、各種薬品を被り易い路面に敷設のマンホー
ル蓋にいたっては、赤く錆び付き、これが市街の景観を
悪くしていた。とくに最近のカラー舗装路でこれが目立
っていた。The above-mentioned tar film has weak adhesion and is easily peeled off in a short time. Especially, the manhole cover laid near the coast, which is easily damaged by salt, and on the road where it is easily exposed to various chemicals, was red and rusted, which made the scenery of the city worse. This was especially noticeable on the recent color paved roads.
【０００４】そこで本発明者等は、この錆付きを防ぐた
めに、アルカリ脱脂等の表面処理をしたのち亜鉛めっき
をして、めっき皮膜を形成することを試みたが、次の問
題点があることに気づいた。すなわち、鋳鉄は組織中に
カーボンが多く含まれており、このカーボンが表面に多
く析出している。めっき時に蓋の表面の鉄面は亜鉛と金
属結合をするが、この表面に析出しているカーボンは亜
鉛とは金属結合をしない。従って、この部分が不めっき
状態あるいはめっきが乗っているだけの状態となりめっ
きの付着力が弱い。加えて蓋表面は総じて滑り止めのた
めに凹凸状に形成されているため、もともとめっき皮膜
が付着し難く密着性が悪い点である。In order to prevent this rusting, the present inventors have attempted to form a plating film by zinc plating after surface treatment such as alkaline degreasing, but there are the following problems. I noticed. That is, cast iron contains a large amount of carbon in its structure, and a large amount of this carbon is precipitated on the surface. During plating, the iron surface of the lid surface forms a metal bond with zinc, but the carbon deposited on this surface does not form a metal bond with zinc. Therefore, this portion is in a non-plated state or a state in which only the plating is overlaid, and the adhesive force of the plating is weak. In addition, since the lid surface is generally formed in an uneven shape so as to prevent slipping, the plating film is originally difficult to adhere and the adhesion is poor.
【０００５】更に、マンホール蓋の表面にめっき皮膜を
形成しただけでは、環境調和の問題がある。つまり路面
に敷設したマンホール蓋のめっき皮膜がキラキラして違
和感を与えるだけでなく、これに太陽光線が当たると、
その反射光が自動車の運転者や付近の住宅、工場などに
入り、まぶしいなどの問題である。本発明の目的は、亜
鉛又は亜鉛合金めっき皮膜の密着性がよく、表面防食性
に優れた鋳鉄製マンホール蓋のめっき方法を提供するに
ある。更に本発明の他の目的は、めっき皮膜のキラキラ
感をなくして環境調和を図った鋳鉄製のマンホール蓋を
得るにある。Further, if a plating film is formed on the surface of the manhole cover, there is a problem of environmental harmony. In other words, not only does the plating film on the manhole cover laid on the road surface glitter and give an unpleasant feeling, but if it hits the sun's rays,
The reflected light enters the driver of the car, nearby houses, factories, etc. and is a problem such as dazzling. An object of the present invention is to provide a method for plating a cast iron manhole cover which has good adhesion of a zinc or zinc alloy plating film and excellent surface corrosion resistance. Still another object of the present invention is to obtain a cast iron manhole cover that eliminates the glittering feeling of the plating film and is environmentally friendly.
【０００６】[0006]
【課題を解決するための手段】本発明は、鋳鉄製のマン
ホール蓋の鋳はだをショットブラスト処理する工程と、
マンホール蓋を酸洗いしたのち水洗いするめっき前処理
工程と、マンホール蓋の外表面に亜鉛又は亜鉛合金のめ
っき皮膜を形成するめっき工程とを順に経て鋳鉄製マン
ホール蓋を製造するにある。更に具体的には、めっき工
程でマンホール蓋を溶融亜鉛又は溶融亜鉛合金のめっき
浴に浸漬して、亜鉛又は亜鉛合金のめっき皮膜を形成
し、冷却時にめっき皮膜上にスパングルを現出させる。
そして、めっき工程後にマンホール蓋を皮膜化成処理し
て、めっき皮膜上に化成皮膜を形成するにある。SUMMARY OF THE INVENTION The present invention comprises a step of shot blasting a cast iron manhole cover made of cast iron,
A cast iron manhole cover is manufactured by sequentially performing a pre-plating process of pickling the manhole cover and then washing it with water, and a plating process of forming a zinc or zinc alloy plating film on the outer surface of the manhole cover. More specifically, in the plating step, the manhole cover is immersed in a bath of molten zinc or a molten zinc alloy to form a zinc or zinc alloy plating film, and spangles are exposed on the plating film during cooling.
Then, the manhole cover is subjected to a film conversion treatment after the plating step to form a conversion film on the plating film.
【０００７】[0007]
【作用】ショットブラスト処理を十分にすることによ
り、マンホール蓋の表面に析出しているカーボンをでき
るだけ落とすとともに、表面の鋳物砂、油分、酸化鉄を
除去する。さらにショットブラスト処理時における、小
さな鋼鉄粒子（ショット）又は鋼砕粒（グリット）の吹
き付けによって、マンホール蓋表面に微細な凹凸を全面
に形成し、亜鉛めっき皮膜を付着しやすくする。By sufficiently performing the shot blasting treatment, carbon deposited on the surface of the manhole cover is removed as much as possible, and molding sand, oil and iron oxide on the surface are removed. Further, during the shot blasting process, by spraying small steel particles (shots) or steel crushed particles (grit), fine irregularities are formed on the entire surface of the manhole cover, and the zinc plating film is easily attached.
【０００８】酸洗処理では、例えば１５〜４５℃に加温
した７〜２０％の塩酸又は硫酸水溶液にマンホール蓋を
浸漬し、これで表面の酸化皮膜を完全に除去する。その
後に水洗い処理し、フラックス処理に入る。フラックス
処理は、例えば５０〜８５℃に加温した飽和状態に近い
塩化亜鉛アンモニウム水溶液にマンホール蓋を浸漬し、
被めっき面を清浄化して、めっきまでの錆の発生を防
ぐ。In the pickling treatment, for example, the manhole cover is immersed in a 7 to 20% hydrochloric acid or sulfuric acid aqueous solution heated to 15 to 45 ° C. to completely remove the oxide film on the surface. After that, it is washed with water and then fluxed. For the flux treatment, for example, the manhole lid is immersed in an aqueous solution of zinc ammonium chloride which is heated to 50 to 85 ° C. and is close to a saturated state,
The surface to be plated is cleaned to prevent the formation of rust before plating.
【０００９】めっき工程では、例えば４４０〜４７０℃
に加熱した溶融亜鉛浴または溶融亜鉛・５％アルミ合金
浴にマンホール蓋を浸漬するが、好ましくはこれを繰り
返して不めっき部分が出ないようにチェックしながらめ
っき皮膜をつくる。亜鉛・アルミ合金めっきによるとき
は、耐食性の向上により有利である。亜鉛・５５％アル
ミ合金浴の場合は浴の温度は６００℃位に設定する。な
お、後述するスパングルをマンホール蓋の模様として利
用しない場合は、電気亜鉛めっきでもよい。In the plating process, for example, 440 to 470 ° C.
The manhole cover is immersed in a hot-dipped zinc bath or a hot-dipped zinc / 5% aluminum alloy bath, which is preferably repeated to form a plating film while checking that no unplated portion appears. Zinc / aluminum alloy plating is advantageous because of improved corrosion resistance. In the case of a zinc / 55% aluminum alloy bath, the bath temperature is set to about 600 ° C. If the spangles described below are not used as the pattern for the manhole cover, electrogalvanizing may be used.
【００１０】なお、めっき後すぐにマンホール蓋は常法
どおりに冷却することになる。すなわち鋳はだ面に鉄と
亜鉛の合金層を形成し、この金属層上に亜鉛層を形成す
ることになるが、冷却に時間をかけ過ぎると合金層が成
長し過ぎて亜鉛層が薄くなり過ぎ、防食性に問題が出
る。一方、急冷すると、めっき面上に現出するスパング
ル（亜鉛の結晶模様）が出にくく、このスパングルをマ
ンホール蓋の表面模様として利用するに不利となる。従
って、めっき後の冷却工程では、６０〜９０℃の温水に
マンホール蓋を１〜３分間浸漬して冷却したのち引き上
げることが望ましい。尤も、スパングルは積極的に現出
させることを必ずしも要さず、それらの場合は温水冷却
によらずに適宜水冷方式ないし空冷方式を採用してもよ
い。Immediately after plating, the manhole cover is cooled in the usual manner. That is, an iron-zinc alloy layer is formed on the casting surface, and a zinc layer is formed on this metal layer.However, if cooling is taken too long, the alloy layer grows too much and the zinc layer becomes thin. It passes, and there is a problem in anticorrosion. On the other hand, when rapidly cooled, spangles (zinc crystal pattern) that appear on the plated surface are less likely to appear, which is disadvantageous in using this spangle as a surface pattern of a manhole cover. Therefore, in the cooling step after plating, it is desirable to immerse the manhole cover in warm water at 60 to 90 ° C. for 1 to 3 minutes, cool it, and then pull it up. However, spangles do not necessarily have to be positively exposed, and in those cases, a water-cooling method or an air-cooling method may be appropriately adopted instead of hot water cooling.
【００１１】めっき後に、めっき皮膜のキラキラ感をつ
や消しするための皮膜化成処理工程に入る。これにはま
ず前処理として５０〜７５℃の弱脱脂液に１〜１０分間
浸漬して、清浄化したのち水洗いし、次に１５〜４０℃
のコロイド状チタン酸液（商品名：日本パーカライジン
グ社製プレバリンＺ）に0.５〜１分間浸漬攪拌して表面
調整する。その後にマンホール蓋を５０〜８０℃のリン
酸亜鉛浴に２〜５分間浸漬し、めっき皮膜上にリン酸亜
鉛の化成皮膜を厚さ５〜３０ｇ／m2に積層形成する。か
くして得られたリン酸亜鉛の化成皮膜は耐剥離強度に優
れグレー色に発色する。そして、溶融亜鉛又は溶融亜鉛
合金のめっき皮膜の場合は、これのめっき表面にスパン
グルが出て化成皮膜を通して見えることになる。なお、
皮膜化成処理は、先のリン酸亜鉛やリン酸鉄によるリン
酸塩皮膜が好ましいが、クロメート処理によることもで
きる。After plating, a film chemical conversion treatment step for matting the glitter of the plating film is started. For this, first, as a pretreatment, it is immersed in a weak degreasing liquid at 50 to 75 ° C for 1 to 10 minutes, cleaned and washed with water, and then 15 to 40 ° C.
The surface is adjusted by dipping and stirring in a colloidal titanic acid solution (trade name: Prevaline Z manufactured by Nippon Parkerizing Co., Ltd.) for 0.5 to 1 minute. Thereafter, the manhole cover is immersed in a zinc phosphate bath at 50 to 80 ° C. for 2 to 5 minutes to form a zinc phosphate conversion coating on the plating coating to a thickness of 5 to 30 g / m 2 . The zinc phosphate conversion film thus obtained has excellent peel resistance and develops a gray color. In the case of a hot-dip zinc or hot-dip zinc alloy plating film, spangles appear on the plated surface and are visible through the chemical conversion film. In addition,
The film chemical conversion treatment is preferably a phosphate coating with zinc phosphate or iron phosphate, but chromate treatment can also be used.
【００１２】[0012]
【発明の効果】本発明方法によれば、マンホール蓋１は
鋳鉄製ではあるが、ショットブラスト処理によって、不
めっきの原因である蓋表面に析出しているカーボンを除
去するとともに鋳砂、油分、酸化鉄等も除去すること、
同時に蓋の全表面に微細な凹凸を形成して、後のめっき
皮膜の付着性を向上してあることとが相まって、めっき
皮膜の密着性が良く、不めっき部分もない防食性に優れ
たマンホール蓋をつくることができる。According to the method of the present invention, although the manhole cover 1 is made of cast iron, the shot blasting treatment removes the carbon deposited on the cover surface, which is the cause of non-plating, and the cast sand, oil, Remove iron oxide, etc.,
At the same time, fine unevenness is formed on the entire surface of the lid to improve the adhesion of the plating film after that, and the adhesion of the plating film is good, and the manhole has excellent corrosion resistance with no unplated part. You can make a lid.
【００１３】また、めっき後にマンホール蓋を皮膜化成
処理してめっき皮膜上に化成皮膜を積層形成してあるの
で、化成皮膜が更なる防食性の向上に資するとともに、
めっき面のキラキラ面をつや消しし、環境調和のとれた
マンホール蓋を得ることができる。更に、溶融亜鉛又は
溶融亜鉛合金のめっき皮膜とし、めっき後の冷却時に徐
冷してめっき面にスパングルが現出するようにしたとき
は、化成皮膜を通して見える該スパングルがマンホール
蓋の表面模様として利用できる利点を有する。Further, since the manhole cover is subjected to a film conversion treatment after plating to form a chemical conversion film on the plating film, the chemical conversion film further contributes to the improvement of corrosion resistance.
You can obtain a manhole cover that is in harmony with the environment by matting the glitter surface of the plated surface. In addition, when a hot-dip zinc or hot-dip zinc alloy plating film is used and the spangle is exposed on the plated surface by slow cooling during cooling after plating, the spangle visible through the chemical conversion film is used as the surface pattern of the manhole cover. It has the advantage that it can.
【００１４】[0014]
ショットブラフト処理工程： 鋳鉄製のマンホール蓋１
の鋳はだにショットブラスト機で鋼製粒子にインペラで
強い遠心力を与えて繰り返し吹き付け、表面に析出のカ
ーボン、鋳砂、油分、酸化鉄を除去するとともに、表面
に微細な凹凸を形成し、該表面を粗面化処理する。同時
に、このときの衝撃で鋳造時の表面の残留応力を取り除
く。 酸洗工程： 次に、３０℃に加温した８％の塩酸水溶液
にマンホール蓋１を分間浸漬し、表面に残っている酸化
鉄を除去し、水洗いをした。 フラックス処理工程： ８０℃に加温した飽和状態に近
い塩化亜鉛アンモニウム水溶液にマンホール蓋１を１分
間浸漬し、フラックス処理をして、めっき面を清浄化す
るとともに酸化亜鉛の付着を防ぐ。Shot rafting process: Cast iron manhole cover 1
With a casting blast machine, a shot blast machine is used to repeatedly spray steel particles with an impeller by applying a strong centrifugal force to remove precipitated carbon, casting sand, oil, iron oxide, and to form fine irregularities on the surface. The surface is roughened. At the same time, the impact at this time removes the residual stress on the surface during casting. Pickling step: Next, the manhole cover 1 was immersed in an 8% hydrochloric acid aqueous solution heated to 30 ° C. for a minute to remove iron oxide remaining on the surface and washed with water. Flux treatment step: The manhole cover 1 is immersed in an aqueous solution of zinc ammonium chloride close to a saturated state heated to 80 ° C. for 1 minute to perform a flux treatment to clean the plated surface and prevent zinc oxide from adhering.
【００１５】めっき工程： マンホール蓋１を４５０℃
の溶融亜鉛浴に浸漬し、５分経過後に引きあげる。この
作業はめっき状態を見ながら数回繰り返してもよい。よ
って得られるめっき皮膜２の厚さを１００μｍとした。Plating process: Manhole cover 1 at 450 ° C.
Immerse in the molten zinc bath of, and pull up after 5 minutes. This operation may be repeated several times while observing the plating state. Therefore, the thickness of the plating film 2 obtained was 100 μm.
【００１６】冷却工程： めっき後１分間空冷し、６８
℃の温水にマンホール蓋を２分間浸漬して冷却し、めっ
き皮膜２には下層に鉄と亜鉛の合金層を形成し、その表
面に亜鉛層を形成し、めっき皮膜２上にスパングルを現
出させた。Cooling process: Air-cooling for 1 minute after plating, 68
Immerse the manhole cover in warm water at ℃ for 2 minutes and cool it. Form an alloy layer of iron and zinc as the lower layer on the plating film 2, form a zinc layer on the surface, and expose spangle on the plating film 2. Let
【００１７】皮膜化成処理工程： 冷却後のマンホール
蓋１を各種前処理後６０℃のリン酸亜鉛浴に３分間浸漬
し、めっき皮膜２上にリン酸亜鉛の化成皮膜３を厚さ２
０ｇ／m2に積層形成した。Coating conversion treatment step: After cooling, the manhole cover 1 is subjected to various pretreatments and immersed in a zinc phosphate bath at 60 ° C. for 3 minutes to form a zinc phosphate conversion coating 3 having a thickness of 2 on the plating coating 2.
It was laminated to form 0 g / m 2 .
【００１８】よって得られた製品マンホール蓋は塩水噴
霧試験によるも防食性が飛躍的に向上し、表面の化成皮
膜３がグレー色を呈してメッキ面のキラキラ感を消し、
かつめっき面のスパングルが縞模様をなして見えるもの
となった。The product manhole cover thus obtained has a dramatically improved anticorrosion property in a salt spray test, and the chemical conversion film 3 on the surface has a gray color to eliminate the glittering feeling on the plated surface.
Moreover, the spangles on the plated surface became visible in a striped pattern.
【図１】鋳鉄製マンホール蓋の要部の概略断面図であ
る。FIG. 1 is a schematic cross-sectional view of a main part of a cast iron manhole cover.
１ マンホール蓋 ２ めっき皮膜 ３ 化成皮膜 1 Manhole cover 2 Plating film 3 Chemical conversion film
───────────────────────────────────────────────────── フロントページの続き (72)発明者 高松 伸悟 大阪府大阪市住之江区北加賀屋３丁目３番 44号 オーエム工業株式会社内 (72)発明者 河野 功 大阪府大阪市住之江区北加賀屋３丁目３番 44号 オーエム工業株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shingo Takamatsu 3-44 Kitakagaya, Suminoe-ku, Osaka City, Osaka Prefecture OEM Industry Co., Ltd. (72) Inventor Isao Kono 3-chome Kitakagaya, Suminoe-ku, Osaka City, Osaka Prefecture No.3, No.44 OM Industrial Co.
Claims (3)
トブラスト処理する工程と、 マンホール蓋を酸洗いしたのち水洗いするめっき前処理
工程と、 マンホール蓋の外表面に亜鉛又は亜鉛合金めっき皮膜を
形成するめっき工程とからなる鋳鉄製マンホール蓋のめ
っき方法。1. A step of shot blasting a cast iron of a cast iron manhole cover, a pretreatment process of pickling the manhole cover with acid and then washing with water, and a zinc or zinc alloy plating film on the outer surface of the manhole cover. A method for plating a cast iron manhole cover, which comprises a plating step to be formed.
又は溶融亜鉛合金のめっき浴に浸漬して、亜鉛又は亜鉛
合金のめっき皮膜を形成し、 冷却時にめっき皮膜上にスパングルを現出させてある請
求項１記載の鋳鉄製マンホール蓋のめっき方法。2. In the plating step, the manhole cover is immersed in a molten zinc bath or a molten zinc alloy plating bath to form a zinc or zinc alloy plating film, and spangles are exposed on the plating film during cooling. The method for plating a cast iron manhole cover according to claim 1.
して、めっき皮膜上に化成皮膜を積層形成する皮膜化成
処理工程を含む請求項１又は２記載の鋳鉄製マンホール
蓋のめっき方法。3. The method for plating a cast iron manhole cover according to claim 1, further comprising a film chemical conversion treatment step of forming a chemical conversion film on the plating film by plating the manhole cover after plating.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12192193A JP3301044B2 (en) | 1993-04-26 | 1993-04-26 | Plating method for cast iron manhole cover |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12192193A JP3301044B2 (en) | 1993-04-26 | 1993-04-26 | Plating method for cast iron manhole cover |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06316945A true JPH06316945A (en) | 1994-11-15 |
| JP3301044B2 JP3301044B2 (en) | 2002-07-15 |
Family
ID=14823215
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12192193A Expired - Fee Related JP3301044B2 (en) | 1993-04-26 | 1993-04-26 | Plating method for cast iron manhole cover |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3301044B2 (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001527157A (en) * | 1997-12-19 | 2001-12-25 | エスエムエス・デマーク・アクチエンゲゼルシャフト | Method for producing strip metal composites by high temperature dip coating |
| JP2010248571A (en) * | 2009-04-15 | 2010-11-04 | Kodama Imono Kk | Method for manufacturing cast iron having erosion resistance to molten aluminum, and cast iron having erosion resistance to molten aluminum |
| WO2019065721A1 (en) * | 2017-09-26 | 2019-04-04 | 日立金属株式会社 | Method for producing plated black-heart malleable cast iron member, plated black-heart malleable cast iron member, and pipe fitting |
| CN110106460A (en) * | 2019-05-21 | 2019-08-09 | 安徽伟宏钢结构集团股份有限公司 | A kind of continuous operation steel member hot-dip galvanizing technique |
| CN110394424A (en) * | 2019-08-29 | 2019-11-01 | 安徽普瑞明精密机械有限公司 | A method of melting, which is carried out, using the pig iron improves spheroidal graphite cast-iron manhole cover intensity |
| CN112609139A (en) * | 2020-12-11 | 2021-04-06 | 东北大学 | Centrifugal spraying equipment for hot-dip galvanized strip steel small spangle production and control system thereof |
| CN113250037A (en) * | 2021-05-08 | 2021-08-13 | 徐静 | Waterlogging prevention device for road safety |
-
1993
- 1993-04-26 JP JP12192193A patent/JP3301044B2/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001527157A (en) * | 1997-12-19 | 2001-12-25 | エスエムエス・デマーク・アクチエンゲゼルシャフト | Method for producing strip metal composites by high temperature dip coating |
| JP2010248571A (en) * | 2009-04-15 | 2010-11-04 | Kodama Imono Kk | Method for manufacturing cast iron having erosion resistance to molten aluminum, and cast iron having erosion resistance to molten aluminum |
| WO2019065721A1 (en) * | 2017-09-26 | 2019-04-04 | 日立金属株式会社 | Method for producing plated black-heart malleable cast iron member, plated black-heart malleable cast iron member, and pipe fitting |
| JPWO2019065721A1 (en) * | 2017-09-26 | 2020-09-17 | 日立金属株式会社 | Manufacturing method of plating-formed black core malleable cast iron member, and plating-formed black core malleable cast iron member and pipe joint |
| CN110106460A (en) * | 2019-05-21 | 2019-08-09 | 安徽伟宏钢结构集团股份有限公司 | A kind of continuous operation steel member hot-dip galvanizing technique |
| CN110394424A (en) * | 2019-08-29 | 2019-11-01 | 安徽普瑞明精密机械有限公司 | A method of melting, which is carried out, using the pig iron improves spheroidal graphite cast-iron manhole cover intensity |
| CN112609139A (en) * | 2020-12-11 | 2021-04-06 | 东北大学 | Centrifugal spraying equipment for hot-dip galvanized strip steel small spangle production and control system thereof |
| CN112609139B (en) * | 2020-12-11 | 2021-09-24 | 东北大学 | Centrifugal spraying equipment for hot-dip galvanized strip steel small spangle production and control system thereof |
| CN113250037A (en) * | 2021-05-08 | 2021-08-13 | 徐静 | Waterlogging prevention device for road safety |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3301044B2 (en) | 2002-07-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5601695A (en) | Etchant for aluminum alloys | |
| US3977839A (en) | Coated metal article and method of coating | |
| JPH06316945A (en) | Method for plating cast iron manhole cover | |
| JP2006057114A (en) | Method of combining surface coating and electroplating for hub | |
| JPS62174385A (en) | Pretreatment for painting by cationic electrodeposition | |
| US3961993A (en) | Coated metal article and method of coating | |
| JPH0759755B2 (en) | Method for manufacturing A-l alloy coated plate for automobiles having excellent system rust resistance | |
| JP3479753B2 (en) | Steel surface treatment method and aqueous chromate treatment liquid | |
| JPS6049711B2 (en) | Manufacturing method of single-sided hot-dip galvanized steel pipe | |
| JPH01108392A (en) | Zn alloy electroplated steel sheet for trim of automobile body and production thereof | |
| JP3263746B2 (en) | Iron manhole cover | |
| US3632453A (en) | Method of manufacturing aluminum-coated ferrous base articles | |
| JPH06116739A (en) | Coating pretreatment and coating method for magnesium alloy product | |
| JPH01108396A (en) | Production of galvannealed steel sheet for coating by cationic electrodeposition | |
| JPS6386888A (en) | Production of zinc-nickel alloy electroplated steel sheet with plated film having superior adhesion under shock at low temperature after painting | |
| JPS6393888A (en) | Zinc alloy electroplated steel sheet having superior resistance to exfoliation by shock after coating | |
| JPS58100691A (en) | Surface-treated steel plate with high corrosion resistance | |
| JPH0432585A (en) | Production of aluminum sheet having superior coatability | |
| JPS63238297A (en) | Production of steel sheet plated with zinc-base alloy | |
| JP2978073B2 (en) | Manufacturing method of electro-galvanized steel sheet excellent in uniform surface appearance | |
| JPH0653935B2 (en) | Multi-layer plated steel | |
| JPS6311692A (en) | Production of zn alloy electroplated steel sheet having superior adhesion to plating | |
| JPH04224666A (en) | Production of hot-dip galvanized stainless steel strip excellent in adhesive strength of plating and corrosion resistance | |
| JPS6293383A (en) | Surface treated steel material having superior corrosion resistance and its manufacture | |
| JPH04378A (en) | Alloyed molten zinc plates steel sheet having superior outside and inside corrosion resistance |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080426 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090426 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100426 Year of fee payment: 8 |
|
| LAPS | Cancellation because of no payment of annual fees |