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MODEL

LOKC

Pilot-to-close, spring biased closed, unbalanced poppet logic element

SERIES 4 / CAPACITY: 1100 L/min. / CAVITY: T-19AU

(X)CONTROL

X Not Adjustable

(D)CRACKING PRESSURE

D 50 psi (3,5 bar)

(N)SEAL MATERIAL

N Buna-N

E EPDM

V Viton

MATERIAL/COATING

Standard Material/Coating

/AP Stainless Steel, Passivated

/LH Mild Steel, Zinc-Nickel

NOTE: DATA MAY VARY BY CONFIGURATION. SEE CONFIGURATION SECTION.

These unbalanced, pilot-to-close logic valves are 2-way switching elements that are spring biased closed. Pressure

at either work port 1 or 2 will oppose the spring and tend to open the valve while pressure at port 3 will tend to

close it. 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

Cavity T-19AU

Series 4

Capacity 1100 L/min.

Maximum Operating Pressure 350 bar

Maximum Valve Leakage at 110 SUS (24 cSt) 0,7 cc/min.

Pilot Volume Displacement 7,7 cc

Pilot Passage into Valve 2,3 mm

Area Ratio, A3 to A1 1.8:1

Area Ratio, A3 to A2 2.25:1

Valve Hex Size 41,3 mm

Valve Installation Torque 474 - 508 Nm

Seal kit - Cartridge Buna: 990019007

Seal kit - Cartridge EPDM: 990019014

Seal kit - Cartridge Polyurethane: 990019002

Seal kit - Cartridge Viton: 990019006

Model Weight 1.16 kg.

snhy.com/

LOKC

Model Code Example: LOKCXDNCONFIGURATION OPTIONS

 2018 Sun Hydraulics Corporation 2 of 2

TECHNICAL FEATURES

These valves will work in Sun's standard T-19A cavity at lower capacity. To realize the full stated capacity, the T-19AU cavity should be used.

Cartridges configured with EPDM seals are for use in systems with phosphate ester fluids. Exposure to petroleum based fluids, greases and lubricants will damage

the seals.

These valves have positive seals between port 2 and the pilot area.

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).

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

LOKCZ Pilot-to-close, spring biased closed, unbalanced poppet logic element with position switch