PN10 flange is a rating of nominal pressure, full nominal pressure of PN have PN6 PN10 PN16 PN25 PN40 for Hyupshin Flange Supplying. Norms of DIN EN1092-1 BS4504 GOST33259-2015 and NFE29203 are have nominal pressure rating, PN10 flanges are medium pressure rating and used in medium pressure piping, PN10 flange thickness is bigger than PN6 but less than PN10-PN40. Pn10 Flanges manufacturer, din 2576 2632 2527 pn10 flanges, en1092-1 pn10 flanges, bs4504 pn10 flanges, gost 33259 pn10 flanges Jinan Hyupshin Flanges Co., Ltd , https://www.iflange.com
The chrome-plated steel sheet, which is called chrome plate for short, is a new type of can-making material that is developed due to the fact that the metal tin resource is small and the cost is high. The United States, Europe and Japan have more and more applications, replacing some of the tinplate materials, China's relatively few applications, which requires the correct understanding of this material, from the technical and ideological analysis. First, the development and characteristics of chrome plating Chromium is a hard, silvery white shiny metal, hardness, wear resistance, matrix binding are very good, high heat resistance, potential than iron negative, but passivation After the potential is more positive than iron. As early as the 20th century, the chrome plating process was used for industrial production. In the United States in 1940, the chrome plate was researched, followed by chromic acid chemical immersion treatment and electrolytic chromic acid treatment, and transferred to mass production. After living in Japan from 1955 onwards, the chromate passivation method was studied and many results were obtained. For example, the Hitop chrome plate of Dongyang Steel Company entered industrial production in 1961; Fuji Steel also produced Con Cupper chrome plates in succession; in 1972, Japanese steel pipes produced Bright Coat chrome. board. European countries also successively produced chrome plates in the 1970s. The original plate and the tin plate of the chrome plate are the same, they are low-carbon steel plates, but the chrome plating layer is very thin (<1.3μm=. The process is the same as that of the tin plate. Therefore, the original tin plating line is generally only required. With the addition of a chrome plating bath, tin plating or chrome plating can be applied.The chrome plating has four layers: a steel substrate, a metallic chromium layer, a hydrated chromium oxide layer and an oil film.Because the substrates are the same, the mechanical properties are the same as those of the tinplate. However, there are some characteristics in application: 1. The cost is about 10% lower than that of tinplate, the appearance of gloss is not as good as that of tinplate 2. The corrosion resistance is inferior to that of tinplate, and the plating is thin and the pinhole rate is high. When used, the inner and outer surfaces should be coated 3. The chrome plate has strong adhesion, and its adhesion to organic paint is 3 to 6 times stronger than that of tinplate, and its anti-sulfidation corrosion ability is also stronger than that of tin plate 4. Chrome plate cannot be soldered ,Can only use lap resistance welding or bonding.5ã€The coating is thin and the toughness is poor, the cans are easy to crack, so it is not suitable to redial the cans, and can be used for deep-flushing cans.6ã€The chrome plate has high temperature resistance, generally in 5000C color No significant change in hardness and no change to softness until 7000C Second, the main issues in the application of chrome plate in food can making From the above understanding, the technical problems restricting the application of chrome plate in the food can making industry are mainly two: one is the corrosion resistance problem.This problem can be from the chrome plating technology Improvements and improvements in post-plating paints to study.Remind that any technical improvements must take into account the cost, in order to maintain the advantages of chromium plating.Currently, the corrosion resistance of chrome plating is not as good as that of tin plating. There is also a certain degree of corrosion resistance, which is suitable for use in weakly acidic foods, packaging, etc. Such foods are very large in markets such as meat, fish, poultry, dairy products, vegetables, carrots, wrist beans, beets, potatoes and various beverages. Soups, etc.. If the strict technical guarantee for the coating, some PH in the 3.7 ~ 4.5 acidic foods can also be chrome plated packaging, such as fruits, pickles, etc.. It is worth mentioning that the corrosion resistance of chrome plate, can not The general concept of chromium corrosion resistance for iron is a general concept. The chrome plating is a cathodic coating and cannot play an electrochemical protective role. In case of high porosity, between the steel substrate and the chromium layer The gold effect is worth studying. Some people tested the corrosion resistance of chrome steel in seawater and found that short-term (2 years) soaking improves the corrosion resistance of carbon steel. However, long-term (more than 2 years) soaking is not only useless but also accelerated. The second problem is the can manufacturing process.The chrome plating has a thin coating and poor toughness, and lacks the flushing and lubricating agent like the tin, so the flushing process needs careful study. The punching process is still possible.Because it cannot be soldered, the three-piece cans must be welded or bonded together. If tinplates are used in combination with chrome-plated plates, tinplates are used for can bodies, and plating plates are used for can bottom covers. It is an application.In addition, the sealing of the can body and the lid is also not suitable for double curling process, otherwise it must be applied.The third, the ideological understanding of the application of chrome plate The above analysis shows that the application of chrome plate in food packaging has its limitations However, it also has its own characteristics and advantages, and it has a relatively large market, so it can be worthy of promotion and development.But as far as China's current reality is concerned, there are still two cognitive issues that belong to the development process. One of China's chrome plate manufacturing industry is almost blank. Since the reform and opening up, China's iron and steel industry has developed rapidly. At the end of the last century, China has become the world's top four steel producer. In 2000, the steel production reached 127 million tons and steel was 130 million tons. However, according to its variety and quality, it has a big difference from the developed countries in the world. About 40% of the products can meet the variety and quality needs, 30% of the varieties are not enough, 20% of the varieties are not good quality, and 10% of the varieties cannot be produced. In fact, China's steel products mainly consist of wire rods and profiles. Plates and pipes are relatively scarce. However, 25% of steel manufacturers are small enterprises, and 33% of steel products are small enterprises. They are old and outdated, and raw materials are unstable. Large enterprises also face the period of institutional reform and technological renovation. Therefore, as a whole, the gap in the quality of steel products in China is still large, the chemical composition fluctuates, the performance is unstable, the dimensional accuracy of finished products is not high, and there are many surface defects. Obviously, there is a high scrap rate for users. Many companies have imported advanced equipment from abroad, but they still need to import materials because domestic raw materials are not applicable. From the perspective of sheet steel materials, although it has grown rapidly every year, domestically produced 19,031,100 tons in 2000, an increase of 10.20%, but the apparent consumption amounted to 39.23 million tons. Therefore, the thin steel sheet has a very large gap in China. It can be imagined that in this context, the packaging industry wants to use chrome plated steel and can only rely on imports. It is worth mentioning that at present, China's tin plate production capacity is surplus, but unfortunately it is mostly low block production line, the product can only be used for dry food packaging. High-grade tinplates that can meet the canning and beverage packaging still rely on imports. It can be seen from this that the raw materials themselves are restricting the development and progress of food packaging. This involves many of the scientific management we are advancing and coordinating development issues. Second, how can our food canners know their packaging containers? Currently, canned food processing companies mainly use tinplates. Their food processing, canning sales, and corresponding equipment and mechanisms are all based on canned tinplates. Any technological innovations and innovations are related to the benefits of the company. It is related to the credibility of the market. Therefore, the application of chrome plate materials is a risk to them. There must be scientific and economic analysis, reliable conditional guarantees, and entrepreneurs with a spirit of reform. Foreign countries have ready experience and equipment, and whether they can adapt to the current situation in China must be carefully explored. The author has learned about individual plants. Due to the limitations of the enterprise mechanism, the factory manager dared not take the risk, because this is a major transformation. It can thus be seen that there are conditional issues in the acceptance of new things by Chinese enterprises, and there are also ideological and cognitive issues. The key is to establish a mechanism for continuous exploration and continuous improvement by enterprises. In particular, after China's entry into the WTO, it faces the internationalization of the market. This must be strengthened and it is imperative. (Wen/Liu Yusheng 1 Mo Haoguang 2 Zhuzhou Institute of Technology 1 Changsha Dairy Factory 2)