Hydraulics glossary
12 entries: short, precise definitions, with an example from our lines and the reference standard.
- Compact hydraulic power pack
- A compact unit that generates hydraulic power: it integrates electric motor, pump, reservoir, manifold and valves in a single block, powering cylinders and actuators on machines and vehicles. At Gazzera: three lines, Group 1 AC, Group 1 DC and Group 0.5 DC. Read more
- Hydraulic power unit (HPU)
- A larger hydraulic power system, custom-engineered for higher flows, pressures and complex control logic, often serving multiple actuators with heat exchangers. At Gazzera: Beyond about 5.5 kW and 20 l/min, the limits of the Group 1 AC line, or with several simultaneous circuits, a compact pack gives way to a power unit. Read more Standard: ISO 4413, safety requirements for hydraulic systems
- Manifold
- An aluminium or cast-iron block on which pump and valves are mounted: it contains the galleries that distribute oil, eliminating most piping. At Gazzera: Aluminium manifolds, machined to drawing with a configurable cavity count. Read more
- Flow rate
- Oil volume moved per unit of time (l/min). It determines actuator speed and equals pump displacement × rotation speed. At Gazzera: Group 1 AC and DC lines up to about 20 l/min, Group 0.5 DC line up to about 3 l/min. Read more
- Working pressure
- The pressure (bar) at which the circuit operates in nominal conditions; it determines the force available at the actuators. At Gazzera: Up to 230 bar continuous, depending on pump displacement. Read more
- Displacement
- Oil volume moved by the pump per revolution (cm³/rev). Together with motor speed it defines the flow rate. At Gazzera: Group 1 pumps from 0.9 to 9.8 cm³/rev; Group 0.5 pumps of 0.88 and 1 cm³/rev. Read more Standard: ISO 4391, parameter definitions for hydraulic pumps and motors
- Pressure relief valve
- A safety valve that limits maximum circuit pressure by discharging excess oil to the reservoir. At Gazzera: In our scissor lift power pack example, it is set at 190 bar. Read more Standard: ISO 4413, safety requirements for hydraulic systems
- Solenoid valve
- A valve operated by an electric coil that routes oil flow; in compact packs it is typically NG6/CETOP 3 interface or cartridge type. At Gazzera: CETOP 3 solenoid valves and modular elements mounted on the manifold. Read more
- S1 / S3 duty
- Electric motor duty classification: S1 = continuous duty, S3 = intermittent periodic duty (percentage of on-time over a 10-minute cycle). At Gazzera: The Group 1 AC line runs in S1 or S3 duty; the DC lines in S3. Read more Standard: IEC 60034-1, electric motor duty types
- NG6 / CETOP 3
- International standard for directional valve mounting interfaces: it guarantees interchangeability between manufacturers. At Gazzera: It is the interface of the solenoid valves fitted on our power packs. Read more Standard: ISO 4401, mounting surfaces for directional valves (size 03)
- Coil
- The electromagnetic winding that operates a solenoid valve; available in several voltages (12/24V DC, 24/110/230V AC) with standard EN 175301-803 (formerly DIN 43650) connectors. At Gazzera: On the DC lines the coil follows the vehicle voltage, 12V or 24V. Read more Standard: EN 175301-803, coil connectors
- Suction kit
- The strainer, filter and fittings that carry oil from reservoir to pump; it must be sized to flow rate and reservoir type. At Gazzera: Strainer, filter and fittings matched to the reservoir and to pump flow. Read more
Have an application in mind?
Send us your diagram or specs: we reply with a technical proposal sized for your application.