Abstract:In the process of repairing the hydraulic turbine in a hydropower plant, the adjustment of the clearance of the guide vane of the turbine is an important and fine work. The main purpose of this work is to adjust the 24 rectangular guide vane of the turbine to a cylinder with a dense and impermeable water. the traditional clearance adjustment method can meet the technical requirements of zero gap after the adjustment , the adjustment process is time-consuming and laborious because of the lack of accurate feedback and monitoring. It may also cause a different pressure between the guide vane, which has a certain influence on the subsequent adjustment. Through collecting the data of the leading water guiding mechanism of the unit, the three-dimensional modeling software is introduced to model accurately, and the clearance of the guide blade of the turbine is simulated under several initial conditions, and the standard position of the guide vane under the condition of the maintenance is compared with the data before the maintenance. In the actual field adjustment process, according to the clearance distribution of the guide vane of different hydraulic turbine and the level of unit maintenance, the adjustment strategy of differential hydraulic turbine guide blade clearance adjustment is put forward according to the standard position of guide vane, which improves the efficiency and precision of the clearance adjustment of the guide vane of the turbine, and ensures the safety of the unit operation.