With the aid of the general washing diagram (see Fig. 3) a special diagram for the particular turbine should be prepared on the basis of the results of the first washing operation. A temperature difference of 30 to 50°C, referred to the duration of the washing operation, will be sufficient. This value corresponds to a pressure difference of 2.5 to 7.5 bar gauge. Enclosed is a washing diagram recorded on a 2.5 MW turbine (see Fig. 4).