What is the difference between 16MnR and carbon steel?
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What is the difference between 16MnR and carbon steel? Why are the tubes in many devices, such as heat exchange equipment, made of carbon steel, while the tube boxes are made of 16MnR? Additionally, in what applications is 16MnR suitable, and what materials cause severe corrosion to it?
16MnR is a plate used for containers, primarily for pressure vessel shells. Composition (%): C, Si, Mn. Mechanical properties: σb (MPa), σs (MPa), δs (%). Steel for containers: 16MnRs – 0.12–0.2, 0.2–0.6, 1.2–1.6; 450–655, 265–345, 18–21. The Q345b grade possesses excellent comprehensive mechanical properties, welding properties, processability, and low-temperature impact resistance. Its mechanical properties at medium temperatures (450°C) and low temperatures (above -40°C) are superior to those of Q235, 15#, and 30# carbon steels, and its quality is stable. This steel is more sensitive to notches than carbon steel; in the presence of notches, its fatigue strength is lower than that of Q235, and cracks tend to form more easily, so care should be taken during processing. Q345 and D grades are suitable for use in harsh conditions in cold regions, as their steel plate strength and low-temperature impact toughness exceed the standard requirements. Such products are suitable for use in the welded structural components of locomotives and vehicles, lifting equipment, mining machinery, motors, boilers, as well as in industries such as petroleum, chemicals, shipbuilding, and bridge construction, as well as in construction machinery used in low-temperature environments. Their advantage lies in their ability to save steel and reduce the weight of structures. The 16MnR series of pressure vessel plates possess excellent comprehensive properties and low-temperature impact toughness; they are also less sensitive to aging and notches, and have superior welding properties (when the thickness is below 30 mm, preheating before welding is generally not required, and heat treatment after welding is not necessary). It is suitable for use as pressure-bearing components in medium-temperature and normal-pressure, as well as medium- and low-pressure vessels, and can also be used to manufacture other non-pressure vessel components. Last edited by The echoes linger on on 2009-3-17 09:26]
16MnR is now renamed Q345R
The pipe is made of carbon steel, and 16MnR is also carbon steel; both are used in environments where corrosion is not a concern. The ‘R’ in 16MnR indicates that it is a plate intended for use in containers, specifically for constructing pressure-bearing container shells.
The pipes are replaced regularly without considering a corrosion margin.
16MnR has a lower carbon content than Q235 and higher strength. The yield stress of Q235 is 235 (at room temperature), while that of 16MnR is 345 (at room temperature). Compared to Q235, it also has better performance in low-temperature conditions and can be used at temperatures above -20°C
16MnR is a specialized steel material for containers
16MnR is now referred to as Q345R; it belongs to the category of low-alloy steels. Its sensitivity to stress corrosion is higher than that of carbon steel, so in environments prone to stress corrosion, carbon steel with lower strength is generally preferred
16Mn steel is a low-alloy structural steel of the 345MPa grade, possessing excellent comprehensive mechanical properties, weldability, processability, and low-temperature impact toughness. Its mechanical properties at medium and low temperatures are superior to those of carbon steels such as Q235-A, 15, and 20; it is a highly mature steel grade with stable quality, suitable for use in temperatures ranging from -40 to 400°C.