A182F53 Round Steel
The so-called duplex stainless steel F53 is composed of ferrite phase and austenite phase in its solid solution structure, which account for about half of the total amount of austenite phase, and the content of common small phase also needs to reach 30%. When the content of C is low, the content of Cr is 18%~28%, and the content of Ni is 3%~10%. Some steels also contain alloying elements such as Mo, Cu, Nb, Ti and N. Compared with ferrite, this kind of steel has higher plasticity, toughness, no room temperature brittleness, better intergranular corrosion resistance and weldability, and maintains 475 brittleness and high thermal conductivity of ferrite stainless steel, which has the characteristics of superplasticity. Compared with austenitic stainless steel, it has higher strength, better resistance to intercrystalline corrosion and chloride stress corrosion. Duplex stainless steel is a nickel-saving stainless steel with excellent pitting resistance.
Application of F53 Dual Phase Steel: Ship power comes from diesel engine, usually using heavy fuel oil. It is the remaining heavy oil after crude oil refining. It has a high viscosity. At room temperature, its viscosity is similar to peanut butter. Its price is not high, but its impurities are very high. Its sulfur content is especially high. It can reach up to 35000 ppm, or 3500 times the sulfur content of ultra-low sulfur diesel oil used in European highway transportation. That's why ocean transportation accounts for 8% of global emissions of sulphur dioxide.
Fuel combustion releases sulphur dioxide and enters the atmosphere in the form of exhaust gases. According to different environmental conditions, sulfur dioxide can easily react with tiny droplets of water to produce sulfuric acid, which is the cause of acid rain. The acidity of acid rain is 10-100 times higher than that of ordinary rain, which causes damage to trees, plants and buildings. If acid rain can not be decomposed in the atmosphere, it will cause a variety of hazards. Sulfur dioxide will cause respiratory diseases, inflammation, and even heart and lung failure when inhaled. In 2011, a Danish study showed that more than 50,000 premature deaths in Europe were related to air pollution caused by shipping.
In 1997, Annex VI to the International Convention for the Prevention of Pollution from Ships (MARPOL) was adopted, which limits the main air pollutants in ship exhaust. The newly revised rules reduce the global upper limit of sulfur content in fuel from 3.5% to 0.5%, which will come into effect in January 2020.
However, the revised edition, which was implemented in January 2015, has reduced the sulfur content caps in the Baltic, North Sea, North America and the Caribbean emission control zones to 0.1%. This means that more than 400 tons of ships traveling in these waters must either use more expensive low-sulfur fuel or modify the ship's flue gas desulfurization device to remove sulfur from the exhaust gas in order to meet the requirements of the new convention.
The wet scrubbing process can remove 99% sulfur dioxide from engine exhaust gas in the ship flue gas desulfurization unit. The liquid is sprayed on the exhaust gas column, which converts sulfur into sulfuric acid, similar to the formation process of acid rain in atmospheric environment.
In places where washing liquids can be safely discharged (offshore waters with moderate or high alkalinity), an open system can be used to wash the exhaust gas only with seawater. In low alkaline sea areas, such as ports, seaports, lakes and canals, closed systems must be used to prevent the discharge of detergents. The closed system uses sodium hydroxide aqueous solution to neutralize and remove sulfur from the formed sulfuric acid. In practical application, many emission control devices adopt open and closed systems, which are more flexible and efficient.
Molybdenum plays a key role in the corrosion resistance of stainless steel, which is very strong inside the flue gas desulfurization unit. According to the different corrosiveness of flue gas desulfurization equipment, several different stainless steel grades are generally used. 316L stainless steel is used in closed systems without using sea water. Open and mixed systems are more corrosive because of the use of seawater, so it is necessary to use molybdenum-containing duplex stainless steel, super duplex stainless steel, super austenitic stainless steel and nickel-based alloy with better corrosion resistance. According to the technical specifications of each manufacturer, pumps, valves and scrubbing towers themselves, especially those high-grade stainless steel and alloys containing molybdenum, need to be manufactured.
In summary, the use of dual-phase steel in ship desulfurization tower is due to its good corrosion resistance. Super austenitic stainless steel and nickel-based alloy can also be used, but the price gap is still there to use according to the situation.
Wuxi Hanyi Alloy Products Co., Ltd. A182F53 Round Steel
(Wuxi Hao Yi alloy products Co. Ltd.)
One-stop Purchasing for Spot Supply Platform
1. Alloy steel, stainless steel/duplex steel/forgings/forgings;
ASTM A182; F5 F9 F11 F22 F91 F92 F36 F51 F53 F55 F60 F6NM
2. Alloy steel/stainless steel, pipes and fittings;
ASTM A213 (ASTM A234) T5 T9 T11 T2 2 T91 T92 WB36 TP304 TP310S TP904L
Stainless steel/duplex steel/pipe/fittings;
ASTM A312 (ASTM A403) TP304L TP304H TP316L TP316Ti TP321H TP317L
IV. Harrington/Nickel Base Alloy/Pipe/Fittings
ASTM B163 (B564 B637) Inconel 600 Inconel 601 Inconel 625 Monel 400
Http://www.hyhjzp.com
Sales hotline 0510-85365099 13382249118 (Weixin and mobile phone number) contact manager Jiang
Sales Hotline 0510-85363330 18262229118 (Wechat and Mobile Phone No.) Contact Xiao Jing