When a double acting cylinder is extending or retracting, the cylinder load includes the load to be moved, internal mechanical friction of the cylinder and what other factor?

When a double acting cylinder is extending or retracting, the cylinder load includes the load to be moved, internal mechanical friction of the cylinder and what other factor?

• A. System pressure
• B. Lubricant viscosity
• C. Back pressure
• D. Ambient temperature

Answer: (C)

Back pressure is the opposing pressure in the exhaust or return path that the cylinder has to work against. In a double-acting cylinder, pressure acts on both sides of the piston, so to extend or retract, the actuator must overcome not only the external load and the cylinder’s internal friction but also the pressure coming back through the opposite port. This back pressure reduces the net force available to move the load, effectively adding to what the system must overcome. System pressure supplies the driving force, so it isn’t the extra load themselves, and lubricant viscosity or ambient temperature aren’t treated as the additional resisting load in this context.

Back pressure is the opposing pressure in the exhaust or return path that the cylinder has to work against. In a double-acting cylinder, pressure acts on both sides of the piston, so to extend or retract, the actuator must overcome not only the external load and the cylinder’s internal friction but also the pressure coming back through the opposite port. This back pressure reduces the net force available to move the load, effectively adding to what the system must overcome. System pressure supplies the driving force, so it isn’t the extra load themselves, and lubricant viscosity or ambient temperature aren’t treated as the additional resisting load in this context.