The turbine is used as a power source for air compressors in large air separation units, saving a large amount of energy for air separation users, and is a turbine-type mechanical device that converts the thermal energy of steam into mechanical energy. The main steam temperature or pressure has a direct impact on the safety performance of the turbine.
In actual operation, as the steam inlet and high pressure parts of the turbine are in direct contact with the high temperature steam, when the steam temperature is too high, the turbine parts will increase in temperature, resulting in lower mechanical strength and lower allowable stress, making the life of the unit relatively shorter; when the main steam temperature decreases, the output power of the turbine decreases accordingly, and in order to keep the power of the unit unchanged, the steam inlet needs to be increased, which causes the axial thrust of the rotor to In addition, the main steam temperature is too low, which will easily lead to increased moisture loss at the low-pressure level and will intensify the erosion of the dynamic blades. The main steam pressure rises and the work capacity of the steam increases. But the pressure is too high, the corresponding nozzle inlet and outlet pressure difference increases, the regulation level blade bending stress increases, will cause blade and nozzle damage and guide tube, steam chamber, steam door and other pressure-bearing parts stress increases, to the unit safety operation caused by the threat; main steam pressure is too low, large air separation unit operating economy is reduced, the turbine available enthalpy drop reduced, steam consumption, axial thrust increases, so that the final stage blade withstand the stress increases resulting in blade deformation.
DEAR air separation in the steam temperature and pressure have design specifications, within the range and according to the actual situation of appropriate adjustments to ensure that the large air separation units economic and stable operation.