Question 422General Subjects - 1st Asst/Chief

The correct answer is D) Misalignment. A vibration reading that exhibits high amplitude/displacement in both the vertical and horizontal directions at 2X the RPM frequency typically indicates a misalignment issue with the rotating machinery. Misalignment causes increased cyclic stresses on the bearings, resulting in high vibration at twice the rotational speed. The other options are incorrect because a bearing problem would typically show vibration at 1X RPM, an imbalance would show higher vibration at 1X RPM, and a bad belt drive issue would likely exhibit vibration at the belt pass frequency, not 2X RPM.