A ship is equipped with the illustrated turbine gear set and a right hand turning propeller. When steam is admitted to the astern element, with sternway on, the high-speed pinion on the high pressure side is__________. See illustration SE-0016.
• Trace the direction of rotation from the propeller shaft back through each gear mesh to the high‑speed pinion. • Remember that each pair of meshing gears rotates in opposite directions. • For a right‑hand propeller, know which way the shaft turns for AHEAD and which way it turns for ASTERN when viewed from astern.
• Start at the propeller: with sternway on a right‑hand propeller, which way is the shaft turning when viewed from astern? • Follow that shaft rotation into the large low‑speed reduction gear, then through the intermediate pinions to the high‑speed pinion on the high‑pressure side. How many gear meshes are there, and how many times does the direction reverse? • Compare the final rotation direction you find for the high‑speed pinion with the described directions in the answer choices.
• Be sure you are viewing all rotations from the same end (the aft end of the reduction gear, as stated in one choice). • Carefully count the number of gear meshes between the propeller shaft and the high‑speed pinion; each mesh flips direction. • Confirm which shafts are directly connected (same shaft = same direction; meshed gears = opposite direction).
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