The casing of steam turbine is generally made into horizontal split type, i.e. upper casing and lower casing. In order to make reasonable use of steel, the casing of small and medium-sized steam turbine is usually divided into high pressure section, 100 medium pressure section and low pressure section by one or two vertical joint surfaces. High-power steam turbines are equipped with high-pressure, medium-pressure and low-pressure casings respectively according to their operating characteristics. After the high pressure and high temperature adopt a double-layer casing structure, the casings divided into an inner casing and an outer casing. The steam is discharged into the condenser after the last stage blades of the steam turbine, and this part of the casing is called the exhaust casing. Know The casing is the casing of the steam turbine. The role of the casing is mainly to separate the flow passage of the steam turbine (nozzles, baffles, rotors, etc.) from the atmosphere to ensure that the steam completes the work process in the steam turbine. In addition, it also supports some stationary components of the steam turbine (diaphragm, nozzle chamber, steam jacket, etc.), withstanding their heavy passage and thermal stress due to uneven temperature distribution along the axial and radial direction of the casing.
Casing and assembly