Created on 03/11/2016
c
2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 1 of 2
MODEL
LODB
Vent-to-open, spring biased closed, unbalanced poppet logic element with pilot
source from port 2
SERIES 1 / CAPACITY: 95 L/min. / CAVITY: T-11A
These unbalanced, vent-to-open logic valves are 2-way switching elements that are spring-biased closed and have
port 2 as a pilot source. With port 3 blocked, the valve will remain in the closed position in the 2 to 1 direction and
will function as a check valve from 1 to 2. With port 3 vented, the valve will open provided there is sufficient
pressure to overcome the spring force. The force generated at port 3, plus the spring force, must be greater than
the sum of the forces acting at port 1 and port 2 for the valve to remain closed. NOTE: The pilot area (port 3) is 1.8
times the area at port 1 and 2.25 times the area at port 2.
TECHNICAL DATA
Maximum Operating Pressure 350 bar
Maximum Valve Leakage at 110 SUS (24 cSt) 0,7 cc/min.
Pilot Volume Displacement 0,66 cc
Area Ratio, A3 to A1 1.8:1
Area Ratio, A3 to A2 2.25:1
Control Orifice Diameter 0,53 mm
Seal kit - Cartridge Buna: 990-011-007
Seal kit - Cartridge Polyurethane: 990-011-002
Seal kit - Cartridge Viton: 990-011-006
(X)CONTROL
X Not Adjustable
(D)CRACKING PRESSURE
D 50 psi (3,5 bar)
(N)SEAL MATERIAL
N Buna-N
V Viton
MATERIAL/COATING
Standard Material/Coating
/AP Stainless Steel, Passivated
snhy.com/
LODB
TECHNICAL FEATURES
These valves open quickly when vented. Time to close is difficult to predict as it is dependant on the rate of flow and the pressure drop created as it closes.
Because these valves are unbalanced, operation is pressure dependent. Opening and closing of the poppet are functions of the force balances on three areas: Port
1 = 100%, Port 2 = 80%, and the Pilot Area = 180%.
These valves are pressure responsive at all ports, therefore it is essential to consider all aspects of system operation through a complete cycle. Pressure changes
at any one port may cause a valve to switch from a closed to an open position, or vice versa. All possible pressure changes in the complete circuit must be
considered to assure a safe, functional system design.
All ports will accept 5000 psi (350 bar).
Corrosion resistant cartridge valves are intended for use in corrosive environments and are identified by the model code suffix /AP for external stainless steel
Model Code Example: LODBXDNCONFIGURATION OPTIONS
Created on 03/11/2016
c
2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 2 of 2
components, or /LH for external zinc-nickel plated components. See the CONFIGURATION section for all options. For further details, please see the Materials of
Construction page located under TECH RESOURCES.
Incorporates the Sun floating style construction to minimize the possibility of internal parts binding due to excessive installation torque and/or cavity/cartridge
machining variations.
PERFORMANCE CURVES
RELATED MODELS
LODB8 Vent-to-open, spring biased closed, unbalanced poppet logic element with pilot source from port 2 and integral T-8A control cavity
