Question 573Steam Plants - Assistant Engineer

The correct answer is A) turbine steam chest. The main throttle valve on a main propulsion turbine admits steam directly into the turbine steam chest, which is the enclosed space that distributes the steam to the turbine blades. This allows the steam to expand and accelerate as it passes through the turbine blades, generating the rotational force that drives the propeller. The other answer choices are incorrect because: B) the nozzle diaphragm is not directly connected to the throttle valve, C) the turbine blades are downstream of the steam chest, and D) the crossover connection is not the direct admission point for the steam.