Question 681Steam Plants - Assistant Engineer

The correct answer is C) a labyrinth packing ring. The labyrinth packing ring helps to minimize the flow of steam between the nozzle diaphragm and the rotor of the turbine. This is because the labyrinth packing ring creates a series of small, restricted flow paths that reduce the pressure drop across the diaphragm, limiting the amount of steam that can escape between the stationary and rotating components of the turbine. The other answer choices are incorrect because they do not specifically address the issue of minimizing steam flow between the nozzle diaphragm and the rotor. A Babbitt liner, deflector rings, and a fluid seal serve different purposes in turbine design and do not directly contribute to reducing the pressure drop and steam flow in this specific location.