Is the cylinder faster during the forward stroke (extension) or the reverse stroke (retraction)?

• A. Forward (extension)
• B. Roughly the same speed
• C. Reverse (retraction) because the rod side has a smaller area
• D. It depends on the load

Answer: (C)

Speed of a hydraulic cylinder is determined by the flow rate divided by the effective piston area. When the rod is inside the bore, it occupies part of the piston’s cross-sectional area, so the rod side has a smaller effective area than the extension side. With the same hydraulic flow, moving a smaller area takes less fluid per unit distance, so the velocity is higher on the rod side. That’s why the retraction stroke is faster than the extension stroke. In real systems, load and friction can modify speeds, but the fundamental reason is the smaller rod-side area leading to a higher retract speed.