Abstract:

In order to improve the heating capacity of the heat supplied unit, the unit needs to be retrofitted. Compared with different steam extraction schemes, the one that uses intermediate valve to control hot reheat steam is feasible, which can meet the needs of users for high temperature and high pressure steam under low load operating conditions. After the transformation, the economy and safety of the unit is analyzed. The results show that with decrease of the load, the main steam flow increases, the efficiency of the high pressure cylinder increases, the efficiency of the medium pressure cylinder decreases and the inflow to mediumpressure and lowpressure cylinder is slightly reduced, the power consumption of the auxiliary machine is slightly increased, and the vibration and axial displacement of the unit are satisfied.

Key words:

heat supplied unit, heating reform, intermediate pressure valve, hot reheating steam, steam extraction