Created on 02/10/2016

 2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 1 of 2

MODEL

PBDB8

Pilot operated, pressure reducing main stage with integral T-8A control cavity

SERIES 1 / CAPACITY: 40 L/min. / CAVITY: T-11A

This valve is a normally open modulating element that incorporates an integral pilot control cavity. The pilot control

cavity will accept any T-8A pressure control cartridge. The valve reduces a high primary pressure at the inlet (port 2)

to a constant reduced pressure at port 1. The pilot cartridge's setting determines the difference in pressure between

reduced pressure (port 1) and the drain (port 3).

TECHNICAL DATA

Maximum Operating Pressure 350 bar

Control Pilot Flow 0,11 - 0,16 L/min.

Pilot Control Cavity T-8A

Seal kit - Cartridge Buna: 990-011-007

Seal kit - Cartridge EPDM: 990-011-014

Seal kit - Cartridge Polyurethane: 990-011-002

Seal kit - Cartridge Viton: 990-011-006

(W)BIAS PRESSURE

W 100 psi (7 bar)

D 25 psi (1,7 bar)

(N)SEAL MATERIAL

N Buna-N

E EPDM

V Viton

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PBDB8

TECHNICAL FEATURES

All three-port pressure reducing and reducing/relieving cartridges are physically interchangeable (i.e. same flow path, same cavity for a given frame size). When

considering mounting configurations, it is sometimes recommended that a full capacity return line (port 3) be used with reducing/relieving cartridges.

Full reverse flow from reduced pressure (port 1) to inlet (port 2) may cause the main spool to close. If reverse free flow is required in the circuit, consider adding a

separate check valve to the circuit.

Main stage orifice is protected by a 150 micron stainless steel screen.

Compound cartridge (pilot and main stage) assembly information is provided for reference only. Cartridges must be ordered separately and assembled at

point of use.

NOTES

Model Code Example: PBDB8WNCONFIGURATION OPTIONS

Created on 02/10/2016

 2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 2 of 2

Pilot operated valves exhibit very low dead-band transition between reducing and relieving modes.

Pilot operated valves exhibit exceptionally flat pressure/flow characteristics, are very stable and have low hysteresis.

Pressure at port 3 is directly additive to the valve setting at a 1:1 ratio and should not exceed 5000 psi (350 bar).

Maximum inlet pressure is determined by the bias spring. The D spring is tested with 2000 psi (140 bar) maximum differential pressure and the W spring is tested

with 5000 psi (350 bar) maximum inlet pressure.

NOTE: With the -8 control option, the main stage valve should first be installed to the correct torque value. The T-8A pilot control valve should then be installed into

the main stage valve to its required torque value.

The -8 control option allows the pilot control valve to be incorporated directly into the end of the relief cartridge via the T-8A cavity. These pilot control cartridges are

sold separately and include electro-proportional, solenoid, air pilot, and hydraulic pilot operation. See Pilot Control Cartridges.

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.

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

PBDB Pilot operated, pressure reducing valve