the extraction point 8 and flows via the open nonreturn valve 9 to the preheater not illustrated it should be explained in addition that some steam escapes in the locking steam lines 19 19 u2032 and the water vapor lines 20 20 u2032 during the starting up operation since a higher pressure is provided via the intermediate extraction lines 16 16 u2032 a further possibility for starting up the high pressure turbine 1 is now illustrated for this purpose increased locking steam pressure is used as can be seen the design of fig2 virtually corresponds to that of fig1 identical features are not explained again in order to avoid repetitions the sole difference is that there is no auxiliary steam line 18 for the supply of the intermediate extraction line 16 and that the steam flow in the locking steam lines 19 19 u2032 has a different direction during the starting up operation the method for starting up the high pressure turbine 21 is also relatively similar at the beginning the intermediate extraction valve 17 should also be closed the turbine sections 2 and 3 are then subjected to a steam treatment via the locking steam lines 19 and 19 u2032 all of the remaining steps and procedures.