老子午夜影院-老子影院我不卡-老子影院我不卡在线理论-老子影院午夜精品欧美视频-伊在人亚洲香蕉精品区-依人九九

Language
working principle
Free appointment to visit the factory

Telephone:0755-26648581/26648781 mobile phone:18033428604

Working principle


For a long time, corrosion is one of the most troublesome hazards of chemical equipment. If you are careless, you may damage the equipment, or cause accidents or even disasters. According to relevant statistics, about 60% of the damage of chemical equipment is caused by corrosion. Therefore, when selecting chemical valves, we should first pay attention to the scientificity of material selection. There is usually a misunderstanding that stainless steel is a "universal material". It is very dangerous to hold stainless steel valves regardless of medium and environmental conditions.


Here are the key points of material selection for some common chemical media:


sulphuric acid


As one of the strong corrosive media, sulfuric acid is an important industrial raw material with a wide range of applications. Sulfuric acid with different concentration and temperature has great corrosion difference on materials. For concentrated sulfuric acid with concentration above 80% and temperature less than 80 ℃, carbon steel and cast iron have good corrosion resistance, but it is not suitable for high-speed flow sulfuric acid and is not suitable for pump valve materials; Ordinary stainless steels such as 304 (0Cr18Ni9) and 316 (0Cr18Ni12Mo2Ti) are also limited to sulfuric acid medium. Therefore, the pump valve for transporting sulfuric acid is usually made of high silicon cast iron (difficult to cast and process) and high alloy stainless steel (No. 20 alloy). Fluoroplastics have good resistance to sulfuric acid, so using fluorine lined valve is a more economical choice.


hydrochloric acid


Most metal materials are not resistant to hydrochloric acid corrosion (including various stainless steel materials), and molybdenum containing high silicon iron can only be used for hydrochloric acid below 50 ℃ and 30%. In contrast to metal materials, most non-metallic materials have good corrosion resistance to hydrochloric acid, so lined rubber valves and plastic valves (such as polypropylene, fluoroplastics, etc.) are the best choice for transporting hydrochloric acid.


nitric acid


Most general metals are rapidly corroded and damaged in nitric acid. Stainless steel is the most widely used nitric acid resistant material and has good corrosion resistance to all concentrations of nitric acid at room temperature. It is worth mentioning that the corrosion resistance of molybdenum containing stainless steel (such as 316 and 316L) to nitric acid is not only better than that of ordinary stainless steel (such as 304 and 321), but sometimes even worse. For high temperature nitric acid, titanium and titanium alloy materials are usually used.


acetic acid


It is one of the most corrosive substances in organic acids. Ordinary steel will be seriously corroded in acetic acid at all concentrations and temperatures. Stainless steel is an excellent acetic acid resistant material. 316 stainless steel containing molybdenum can also be used for high temperature and dilute acetic acid steam. For high temperature and high concentration acetic acid or other corrosive media, high alloy stainless steel valve or fluoroplastic valve can be selected.


主站蜘蛛池模板: 爱草在线 | 中文字幕成人 | 性满足久久久久久久久 | 91人成亚洲高清在线观看 | 日本免费不卡视频一区二区三区 | 亚洲码在线中文在线观看 | 国产在线观看不卡免费高清 | 精品自拍视频在线观看 | 91高端极品外围在线观看 | 国产日韩一区二区三区在线观看 | 一级毛片免费全部播放完整 | 日韩a在线观看 | 欧美亚洲另类综合 | 手机看片自拍自拍自拍 | 日日做日日摸夜夜爽 | 亚洲第一黄色网 | 国产一区二区精品尤物 | 自拍偷拍国语对白 | 亚洲成人国产 | 视频在线一区 | 国产在线91精品入口 | 成人欧美视频在线看免费 | 欧美亚洲综合另类在线观看 | 欧美三级一区二区三区 | 一级毛片在线不卡直接观看 | 99热在线观看免费 | 天天操你 | 欧美日韩综合高清一区二区 | 91免费网站 | 久久好色 | 亚洲国产成人99精品激情在线 | 2021精品国产综合久久 | 国产高清在线精品 | 91国视频在线| 清纯唯美亚洲综合激情 | 欧美成人午夜精品免费福利 | 99久久免费国产精精品 | 精品国产品国语在线不卡丶 | 久久免费福利 | 亚洲蜜芽在线精品一区 | 欧美成a人片在线观看久 |