Question 305Steam Plants - 1st Asst/Chief

The correct answer is C. Explanation: 1) Scratching - Hard particulates in lubricating oil: Scratches on gear teeth are often caused by hard particles in the lubricating oil, which can score the surface. 2) Pitting - Lubrication deficiency, local micro welding: Pitting on gear teeth is typically caused by a lack of lubrication, leading to localized welding and tearing of the surface. 3) Galling - Seizure on pitch line with plastic metal flow: Galling is a form of severe adhesive wear caused by seizure of the gear teeth, resulting in plastic deformation of the metal. 4) The other options do not accurately describe the causes of these gear tooth conditions as they relate to helical main reduction gearing.