What does the term "double-acting cylinder" mean?

A double-acting cylinder refers to a type of hydraulic cylinder that can exert force in both the extension (outward) and retraction (inward) strokes. This is achieved by having two separate chambers within the cylinder, which allows hydraulic fluid to enter and exit both sides of the piston. When hydraulic fluid is directed into one chamber, the piston moves in one direction, creating an extension. Conversely, when fluid is directed into the opposing chamber, the piston moves back, resulting in retraction. This dual functionality enables double-acting cylinders to perform work in both directions, making them versatile for various applications, including lifting and pushing tasks.

In contrast, options like the cylinder that can only apply force in one direction describe a single-acting cylinder, which operates using pressure on just one side of the piston. The mention of not using hydraulic fluid is inaccurate because hydraulic fluid is essential for their operation. Furthermore, the idea of operating at double standard pressure does not pertain to the classification of cylinder types but rather refers to the pressure at which hydraulic systems can function.