Question 615Steam Plants - Assistant Engineer

The correct answer is B) a deep flexible I beam support. The reason this is the correct answer is that the axial expansion of a steam turbine rotor due to temperature changes needs to be accommodated by the turbine design. This is typically achieved through the use of a deep flexible I-beam support structure, which allows the turbine casing to move and expand axially as the temperature changes, without imposing excessive stresses on the rotor. The other answer choices are not directly related to accommodating axial expansion. Casing flexible joints, pivoted-shoe type thrust bearings, and rotor position indicators serve other purposes in steam turbine design and operation, but do not specifically address the need for axial expansion allowance.