Objet de la recherche «*».

Periodic change in the pressure in a device from values above atmospheric pressure to values below atmospheric pressure (e.g. on pumps between the suction and pressure phase).

Changes in the pressure due to a change in the inlet pressure with a given flow.

Valve with a rotating shaft as the control element that houses the control bores (Figure D 39) . Rotary valve are only used infrequently because their actuation is difficult to automate.

Distance covered by a piston from the starting point to an end point and back to the starting point. Forward stroke : extension of a piston (mostly the same as the working stroke), Return stroke : ret

Triggers an actual damping process that stabilises the drive as the load pressure changes. Damping devices can operate mechano-hydraulically as throttle valves or bypass valves or electro-mechanically

"Blowing past" a piston seal. With large pressure gradients it can occur that the seal is not pressed against the sealing surface, instead it is pressed into the grove (Figure B 21) .

Non-standardised short term used for hydraulic oils with additives designed to provide protection against ageing, corrosion and wear, as well as an additive with emulsifying (dispersing) and detergent

The control element is a flat plate that moves in the housing. Valves with flat slider are primarily used as directional valves.

Throttle valve that due to suitable formation of the control edge (e.g. by means of notches) has very good resolution in the low flow range.

The most important parameters for the effectiveness of filters are: Alpha value of filters , Beta value (β value) , Filter cumulative efficiency , (degree of retention), Dirt holding capacity of a fil