Function and configurationPressure relief valve types ZDB and Z2DB are pilot operated and sandwich structure. They are used to limit the pressure in a hydraulic system. They consist of the housing (7)...
Product Detail
Function and configuration
Pressure relief valve types ZDB and Z2DB are pilot operated and sandwich structure. They are used to limit the pressure in a hydraulic system. They consist of the housing (7), together with one or two pressure relief valve cartridges (4). The system pressure is set by the inserted relief valve(4).
At static position, the valves are closed. Pressure in port A acts on the spool (1). Pressure fluid flows through orifice (2) to the spring loaded side of the spool (1) and through orifice (3) to the pilot poppet (6). If the pressure in port A rises beyond the value setting at spring (5), the pilot poppet (6) opens. Fluid can flow from the spring loaded side of spool (1), orifice (3), and channel (8) into port T. The pressure drop moves spool (1) to open the connection from A to T, while the setting pressure at spring (5) is maintained. Pilot oil returns from the two spring chambers via port T externally.
Notes:
The pilot relief valves have more internal leakage, If lower leakage is demanded, such as safety valve, itis recommended to choose direct operated pressure relief valves, ZDBD type.
Symbols
11
Ordering code
Technical data
| Fluid | Mineral oil suitable for NBR and FKM seal |
| Phosphate ester for FKM seal | |
| Fluid temperature range ℃ | -30 to+80 (NBR seal) |
| -20 to+80 (FKM seal) | |
| Viscosity range m㎡/s | 10 to 800 |
| Degree of contamination | Maximum permissible degree of fluid contamination: Class 9. NAS 1638 or 20/18/15, ISO4406 |
| Max.operating pressure bar | to 315 |
| Max.adjustable pressure bar | 50;100;200;315 |
| Max. flow-rate L/min | 60 |
| Type ZDB6 kg Weight Type Z2DB6 kg | Approx.1.2 |
| Approx.1.9 |
Characteristic curves(Measured at oil =40°C +5°C, using HLP46)
Unit dimensions
Unit dimensions
