Question 340Steam Plants - 1st Asst/Chief70% to pass
If steam is admitted to the main propulsion turbine with the jacking gear engaged, which of the following problems can occur?
AI Explanation
The correct answer is A) Destruction of the jacking gear.
When steam is admitted to the main propulsion turbine with the jacking gear engaged, the sudden influx of steam can generate excessive torque and force, which can lead to the destruction of the jacking gear. The jacking gear is designed to rotate the turbine shaft slowly during maintenance or startup, and it is not built to withstand the full power of the turbine under steam. Engaging the jacking gear while the turbine is under steam can cause the gear to fail or become severely damaged.
The other options are incorrect because they do not accurately describe the primary risk of admitting steam to the turbine with the jacking gear engaged. Options B, C, and D may be potential issues, but they are not the most immediate and critical concern in this scenario.
Related Questions
#338 The original bridge gage reading for a reduction gear bearing was measured as .008 inches. A year later, the bridge gage reading for the same bearing is .010 inches. This indicates _______________.#339 The main propulsion turbine can be damaged by _______________.#341 The part shown in the illustration would be located between which of the following components of a modern geared turbine main propulsion unit? Illustration SE-0001 #342 Which of the following statements is true concerning the coupling shown in the illustration? Illustration SE-0001 #343 Which of the devices listed is commonly used to compensate for the expansion and minor misalignments occurring between the main turbine rotor and the reduction gear?