Response time of a cylinder
Time that is measured between the hydraulic fluid entering the cylinder and the start of the piston movement.
Electric-hydraulic analogy
The understanding of some processes in fluid technology is improved if use is made of the analogies that exist between electrical and hydraulic laws. Given specific boundary conditions, it is possible
Ageing of seals
Many of the additives contained in mineral oil act like a vulcanising agent on elastomers. For this reason vulcanisation can occur at high temperatures; this action is termed ageing. The consequence o
Settling time
Time span that starts when the value for the controlled variable after a step in the disturbance variable or reference variable exceeds a pre-defined portion of the control error and ends when it retu
Positioning error
Error in the of a which is below the response threshold of the continuously adjustable valve . Normally, less than 5% of the valve current is needed to bring the speed of a closed circuit position con
Control power
Power of the input signal, which is necessary to control a valve under defined conditions (DIN 24 311).
Area ratio
The area ratio of a hydraulic cylinder is calculated from the square of the piston diameter dp divided by the square of the difference between the piston and rod diameters dp - dr. Calculate the area
Flow rate-dependent pressure loss
Pressure difference as a function of the flow rate , e.g. for the reversed flow rate direction on valves with bypassing check valve:
Differential transformer
Inductive position measurement
Breather filter
Filter on the hydraulic fluid tank that filters the air flowing in as the pump draws fluid to prevent contamination by this route. Its filtration grade should correspond to that of the oil filter.