A ball screw whose load is on the same side of the ball groove when operated in both directions is _______________ mounted.

• A. Horizontally
• B. Vertically
• C. Diagonally
• D. Inverted

Answer: (B)

Understanding how gravity interacts with a ball screw helps explain why vertical mounting is the right choice here. When the screw is mounted vertically, the weight of the load acts along the axis of the screw. As you move the nut in either direction, the load stays on the same side of the ball groove because gravity isn’t shifting from one side to the other relative to the groove. This leads to consistent loading of the groove in both directions and avoids changing which side of the groove bears the load.

In other orientations, gravity acts differently relative to the groove as you change direction, so the side of the ball groove carrying the load can change when you reverse motion. Horizontal mounting, inverted mounting, or diagonal mounting all introduce scenarios where the load may not stay on the same side of the groove in both directions, making vertical mounting the configuration where the stated condition is met.