Design temperature 300℃
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May I ask whether chromium-molybdenum heat-resistant steel is required for pressure vessels and pipelines with a design temperature of 300°C? Are Q345R and 20 steel pipes acceptable? Operating temperature: 250°C; media: H2, CH4, H2O, etc.; design pressure: 1.0 MPa
Reply to 1# yc11311: That’s fine~ There’s no need to use chromium-molybdenum heat-resistant steel; 345 and 20 will do. It’s best not to let the temperature exceed 400 degrees
Temperature is one aspect of material selection. In addition, this equipment contains hydrogen (the exact concentration is unknown), and the temperature is above 200°C; it is recommended to consider the issue of hydrogen corrosion in accordance with clause 6.7.3 of HG 20581-1998, the regulations for selecting materials for steel chemical processing vessels. At an absolute pressure of 1.1 MPa, the saturated temperature of water is 184°C; therefore, if there is water vapor present in the equipment, corrosion issues need to be considered as well, unless the oxygen content is controlled.