When calculating the work done by a hydraulic cylinder, you must know the hydraulic pressure and the pistons:

The calculation of work done by a hydraulic cylinder is fundamentally based on the hydraulic pressure and the effective area of the piston along with the stroke length.

The area of the piston is crucial because hydraulic force is determined by multiplying the pressure exerted by the fluid with the area of the piston that is acting on that pressure. In hydraulic systems, the force produced can be expressed as:

Force = Pressure x Area.

Thus, having the area allows for the accurate calculation of the force being exerted by the hydraulic fluid on the piston.

The stroke of the piston is also essential because work done is defined as force multiplied by distance. The stroke represents the distance over which the force is applied. Therefore, to determine the total work done by the hydraulic cylinder, the effective area of the piston and the length of the stroke must be known.

Combined, these two parameters enable the calculation of work as:

Work = Force x Stroke = (Pressure x Area) x Stroke.

Knowing just the rod diameter, diameter and speed, or stroke and speed does not provide the complete information necessary for calculating the total work. Thus, the area and stroke are indeed the critical factors that must be known when dealing with hydraulic cylinders.