E 5.169.1.1/01.13
94
Pressure Relief Valve
Poppet Type, Direct-Acting
Metric Cartridge – 420 bar
DB12120A
Up to 120 l/min
Up to 420 bar
The pressure relief valve DB12120A is a
direct-acting, spring-loaded poppet valve. Its
function is to relieve pressure in the system.
It is normally closed. If the pressure at port
1 exceeds the pre-set spring tension, the
poppet is lifted off the seat and oil ows from
port 1 to port 2.
This continues until the system pressure is
equal to the spring tension and the valve
closes again.
Important: Pressures at port 2 are additive
to the opening pressure! If the connections
are incorrect or if the pressure has been set
above the operating pressure, the safety
function of the valve is disabled.
FEATURES
z Excellent stability throughout the entire ow range
z External surfaces zinc-plated and corrosion-proof
z Hardened and ground internal valve components to ensure minimal wear and
extended service life
z Low pressure drop by CFD optimized ow path
z Various pressure ranges up to 420 bar
FUNCTION
SPECIFICATIONS
Operating pressure: max. 420 bar
max. 100 bar at port 2 (tank)
Nominal ow: max. 120 l/min
Pressure setting ranges: 5 to 30 bar
30 to 55 bar
55 to 90 bar
10 to 150 bar
10 to 250 bar
10 to 350 bar
10 to 420 bar
Media operating temperature range: min. -20 °C to max. +120 °C
Ambient temperature range: min. -20 °C to max. +120 °C
Operating uid: Hydraulic oil to DIN 51524 Part 1 and 2
Viscosity range: min. 7.4 mm²/s to max. 420 mm²/s
Filtration: Class 21/19/16 according to ISO 4406 or
cleaner
MTTF
d
: 150 years (see "Conditions and
instructions for valves" in brochure 5.300)
Installation: No orientation restrictions
Materials: Piston: hardened and
ground steel
Seals: FKM (standard)
NBR (optional, media
temperature range
-30 °C to +100 °C)
Back-up rings: PTFE
Cavity: 12120A
Weight: 0.42 kg