Which cylinder type has two working ports and can perform work in both directions by supplying fluid to either port?

Which cylinder type has two working ports and can perform work in both directions by supplying fluid to either port?

• A. Single-acting cylinder
• B. Poppet valve
• C. Double-acting cylinder
• D. Hydraulic Motor

Answer: (C)

This question tests how hydraulic cylinders achieve movement in both directions. A cylinder that can do work in both directions must be able to push the piston one way with pressure on one side and pull it back the other way with pressure on the opposite side. Two working ports provide that capability: pressurizing one port pushes the piston toward the other chamber, extending the rod; pressurizing the opposite port pushes it back, retracting the rod. A double-acting cylinder uses hydraulic fluid on both ends of the piston to control both extension and retraction.

In contrast, a single-acting cylinder has only one active port for pushing; its return is usually via a spring or external load, so it cannot actively move in both directions using fluid pressure. A poppet valve is just a valve component, not a cylinder, and a hydraulic motor converts hydraulic energy to rotation, not linear extension or retraction.