Open loop control system
series circuit) of several subsystems: For example, one subsystem is the plant to be influenced, in fluid technology this is often a cylinder with a connected load, the second subsystem is the immediately
Pipe capacity
accommodated based on the pressure increase required. It is a function of the compressibility of the fluid. The compressibility of the oil in a pipe is increased by the elasticity of the walls and any undissolved
External gear pump
gear wheels with teeth on the outside that rotate engaged in each other. As a result the hydraulic fluid is pressed out of the gaps between the teeth on the outlet side, while the necessary vacuum is produced
Contact seals
the pressure of the medium (elastomer seals). These sealing elements are predominantly elastic in fluid technology and made of elastomers or thermoplastics (materials for seals). In addition metal seals
Oil cooler
cooler : The oil flow passes through pipes with turbulence inserts to increase heat transfer. The fluid in these pipes flows in the opposite direction to the cooling water ( Figure O 4 ). Air-cooled oil
Hydromechanical efficiency
assembly, M Δp = losses due to pressure difference (friction and jamming forces), M ν = losses due to fluid friction and M ρ = flow losses. These give a total loss torque M V With hydraulic pumps, this loss
Internal gear pump
in most cases whose outer (ring gear) has teeth on the inside. The inner sprocket is smaller. The fluid is conveyed in the spaces between the gaps in the teeth of the two gear wheels. Thanks to a long contact
Flow resistance of filters
grade , the flow rate, the filter surface area and design as well as on the viscosity of the pressure fluid and therefore on its actual temperature (Figure F 13) . As the pressure drop is not linear, but instead
Filter size
atmosphere in which the system is operating, The permissible pressure drop The viscosity of the hydraulic fluid and thus its temperature at that moment For the selection of the size the figures are available from
Mineral oils
Most commonly used form of hydraulic fluid (" oil hydraulics "). Their high level of lubricity and relatively high viscosity make it possible to use gap seals in pumps and valves and therefore choose a