Function and configurationTypes DB and DBW pressure valves are pilot operated pressure relief valves, used to limit (DB) or limit and unload (DBW) pressure via solenoid operation. The pressure relief ...
Product Detail
Function and configuration
Types DB and DBW pressure valves are pilot operated pressure relief valves, used to limit (DB) or limit and unload (DBW) pressure via solenoid operation. The pressure relief valves consist of main valve (1) with main spool cartridge (3) and pilot operated valve (2) with pressure adjustment elements.
Type DB pressure relief valves
The pressure of channel A acts on the main spool (3), meanwhile, pressure is applied via control line (6) and (7) with orifice (4) and (5) on the spring loaded side of the main spool (3) and on the ball (8) in the pilot operated valve(2). If the pressure in channel A rises excess the setting value at the spring (9), the ball (8) opens against the spring (9). As for the internal control forms, signal is given by control oil (10) and (6) supplied by channel A. The oil from the spring loaded side of the main spool (3), via control line (7), orifice(11), and ball (8), then flows into spring chamber (12). External drain - type DB...L5X...Y, oil flows via control line(14) into the tank. In virtue of the orifice (4) and (5), the pressure drop arises at the main spool (3), and the connection from port A to port B is open while the operational pressure setting maintained stable. The pressure relief valve may unload or shift the different pressure (second rated pressure value) in virtue of external control port X (15).
Type DBW pressure relief valves
The function of pressure relief valve type DBW is the same with pressure relief valve type DB, the difference is that valve type DBW operates unloading via a built-on directional valve(16).
Function and configuration
Pressure relief valves with switching shock damping (sandwich), type DBW../..S..R12
Switching shock damping (17), the connection from B2 to B1 opens with delay to avoid peak pressure spikes and decompression in the return line. It is fitted between pilot valve (2) and the directional valve (16).
The relief degree (decompression impact) is determined by the size of the orifice (18).
Orifice Ø1.2mm is recommended. (ordering detail:..R12 ..).
Symbols
11
Technical data
| Fixing position | Optional | ||||||
| Weight | DB...10 | DB...15 | DB...20 | DB...25 | DB...30 | ||
| Sub-plate mounting | DB kg | Approx.3 | - | Approx.3.9 | - | Approx.5.3 | |
| DBW kg | Approx.4.5 | - | Approx.5.4 | - | Approx.6.8 | ||
| DBC kg | Approx.1.2 (Type DBWC add 1.5)kg | ||||||
| DBC10 or 30 kg | Approx.1.5 (Type DBWC10 and 30 add 1.5)kg | ||||||
| Threaded connection | DB..G.. kg | Approx.5.3 | Approx.5.2 | Approx.5.1 | Approx.5.9 | Approx.5.8 | |
| DBW..G.. kg | Approx.6.8 | Approx.6.7 | Approx.6.6 | Approx.7.4 | Approx.7.3 | ||
| Switching shock damping kg | Approx.0.6 | ||||||
| Techinical parameters of directional valve | Refer to the solenoid valvetype WE6,normally close use 3WE6A9,normally open use3WE6B9 | ||||||
| Fluid | Mineral oil - suitable for NRB and FRMseal | ||||||
| phosphate ester-suitable for FKM seal | |||||||
| Fluid temperature range ℃ | -30 to +80(NRB 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 | Port A,B,X,P 4 bar | 350 | |||||
| Port T (DB) bar | 315 | ||||||
| Max.back pressure | Port Y DB bar | 315 | |||||
| Port Y or T DBW bar | AC up to 160,DC up to 210 | ||||||
| Max.setting pressure bar | 50;100;200;315;350 | ||||||
| Min.setting pressure bar | Interrelated with Q(refer to the curve) | ||||||
| Sizes | 10 | 15 | 20 | 25 | 30 | ||
| Max.flow- rate | sub-plate mounting L/min | 250 | - | 500 | - | 650 | |
| threaded connection L/min | 250 | 500 | 500 | 500 | 650 | ||
Ordering code
Notes:
The pilot relief valves may have lower starting pressure and higher flow, but have higher internal leakage,
If lower leakage is required, such as safety valve, it is recommended to choose direct operated pressure relief valves, DBD type.
The integrative performance of pilot relief valves with 'U' is not good as the standard version, except lower opening pressure.
Performance curves(Measured at oil =40°C +5°C, using HLP 46)
The characteristic curves are measured with external pilot oil drain at zero pressure.With internal pilot oil drain, the inlet pressure at port B should be added to the value presented as curves.
Unit dimensions
·Sub-plate mounting
| Type | L1 | L2 | L3 | L4 | L5 | L6 | L7 | L8 | L9 | B1 | B2 | D1 | D2 | D3 | D4 | O-ring(A, B) | O-ring(X) |
| DB/DBW 10 | 91 | 53.8 | 22.1 | 27.5 | 22.1 | 47.5 | 0 | 25.5 | 2 | 78 | 53.8 | 14 | M12 | 6 | 12 | 17.12x2.62 | 9.25x1.78 |
| DB/DBW 20 | 116 | 66.7 | 33.4 | 33.3 | 11.1 | 55.6 | 23.8 | 22.8 | 10.5 | 100 | 70 | 18 | M16 | 6 | 22 | 28.17x3.53 | 9.25x1.78 |
| DB/DBW 30 | 147.5 | 88.9 | 44.5 | 41 | 12.7 | 76.2 | 31.8 | 20 | 21 | 115 | 82.6 | 20 | M18 | 7 | 30 | 34.52x3.53 | 9.25x1.78 |
Unit dimensions
.Threaded connection
Note:
On threaded connection valve,series L5X and series 30 havedifferent connection dimensions.If series 30 valves need to bereplaced by series L5X ones, thepitch of installation holes andthe position of external tappingshall be changed.
different connection dimensions. If series 30 valves need to be replaced by series L5X ones, the pitch of installation holes and the position of external tapping shall be changed.Outline and installation dimension of series30 threaded connection valve:
| Type | B1 | D3 | H1 | H2 | H3 | H4 | L1 | L2 | L3 |
| DB 10 G | 63 | 9 | 27 | 125 | 10 | 62 | 85 | 14 | 62 |
| DB 15 G | |||||||||
| DB 20 G | 57 | ||||||||
| DB 25 G | 70 | 11 | 42 | 138 | 13 | 66 | 100 | 18 | 72 |
| DB 30 G |
Unit dimensions
With main spool valve (DBC10 or 30) or without main spool valve (DBC, DBT)
Remote pressure adjusting valve
.Ordering code
.Symbol
.Connection dimension
