Question 347Steam Plants - 1st Asst/Chief
70% to passWith vacuum up and the main propulsion turbine standing by while awaiting engine orders, it is necessary to roll the unit alternately ahead and astern every five minutes to _______________.
Areduce the possibility of warping the turbine rotors
Bwarm the astern guarding valve and the low lube oil pressure throttle trip
Cslowly bring the lube oil and bearings to operating temperature
Ddistribute the gland sealing steam evenly throughout the glands
AI Explanation
The correct answer is A) reduce the possibility of warping the turbine rotors. When a turbine is standing by, it is important to periodically roll the unit alternately ahead and astern in order to prevent the rotors from becoming warped or misaligned due to uneven heating or cooling. Constant rolling helps distribute the heat evenly throughout the turbine, maintaining the proper shape and alignment of the rotors. The other options, while relevant to turbine operation, do not directly address the need to prevent warping of the rotors during standby periods.
Related Questions
Q93:If the main condenser were operating at a vacuum of 28.5"Hg, a condensate discha... Q160:When operating under constant load, the superheated steam temperature may rise a... Q200:Which of the following represents a significant system limitation to be aware of... Q161:While steaming underway the second engineer reports a low superheater outlet tem... Q136:A boiler superheater safety valve is set to lift at 450 psi
Ready to test your knowledge?
Take a Steam Plants - 1st Asst/Chief Practice ExamOfficial Resources