Refers to the compliance of system elements (compressibility of the oil, elasticity of the pipe, spring effect of a hydraulic accumulator):
The hydraulic capacity should be kept as low as possible in the interest of having a stiff drive. This can be achieved by having a low dead volume V o between control and actuator. The hydraulic capacity for cylinder drives is dependent on the piston position (Figure H 18). In the event of pressure reductions, an
increase in C h may have a beneficial effect on dynamic performance.
Figure H 18: Hydraulic capacity of a cylinder based on the stroke