DIRECTIONAL VALVES
DESCRIPTION
A screw-in, cartridge-style, bypass-type, pressure-compensating element, with
integral fl ow regulator for load sense signal drain. The internal pressure-compensated
fl ow regulator restricts the load signal bleed fl ow in order to minimize system losses
even at high operating pressures. The main compensator element holds the valves
primary fl ow constant regardless of load pressure changes.
OPERATION
The EPFR20-S35 is a spring-biased spool-type valve with an internal pressure-com-
pensated fl ow regulator between
➁ and ➂. When used as a pump unloading com-
pensator, this valve will bypass fl ow to tank at port
➁ when system pressure reaches
the load pressure plus the bias spring value. When the system load is neutralized, the
load signal is bled through the fl ow regulator bringing the valve to stand-by condition.
FEATURES
• Multiple function in a single cavity.
• Low bleed fl ow throughout the operating pressure range.
• High system effi ciency.
• Industry common cavity
RATINGS
Operating Pressure: Cartridge only: 320 bar (4600 psi);
Aluminum housing: 207 bar (3000 psi); Ductile iron housing: 345 bar (5000 psi).
Flow: 303 lpm (80 gpm); See Performance Chart
Maximum Flow Loss between
➂ and ➁: 0.95 lpm (0.25 gpm) at 320 bar (4600 psi)
Bias Spring Pressure Options: 6.2 bar (90 psi); 11.0 bar (160 psi)
Operating Fluid Temperature: -40°C to 120°C with Buna N seals;
-35°C to 204°C with Fluorocarbon seals;
-54°C to 107°C with Polyurethane seals
Filtration: See page 9.010.1
Fluids: Mineral-based or synthetics with lubricating properties at viscosities of
7.4 to 420 cSt (50 to 2000 sus); See Temperature and Oil Viscosity, page 9.060.1
Installation: No restrictions; See page 9.020.1
Cavity: VC20-S3; See page 9.120.1; Cavity Tool: CT20-S3xx; See page 8.600.1
Seal Kit: SK20-S3x-MM; See page 8.650.1
PERFORMANCE (Cartridge Only)
SYMBOL
4.468.1
HYDRAFORCE
.com
®
EPFR20-S35 Pressure Compensator with Internal
10.3/150
13.8/200
17.2/250
20.7/300
24.1/350
27.6/400
31.0/450
34.5/500
37.9/550
6.9/100
3.4/50
38
10
76
20
114
30
151
40
189
50
227
60
365
70
303
80
PRESSURE DROP bar/psi
FLOW lpm/gpm
Inlet Pressure vs. Bypass Flow at No-Load Flow Demand
32 cSt/150 sus oil at 40nC
160 psi Spring
80 psi Spring
57/15
76/20
95/25
114/30
132/35
151/40
170/45
189/50
208/55
38/10
19/5
69
1000
138
2000
207
3000
276
4000
345
5000
FLOW lpm/gpm
PRESSURE bar/psi
Flow vs. Load Pressure
32 cSt/150 sus oil at 40nC
Blue rectangles are links to other catalog pages.
DIMENSIONS
TO ORDER
EPFR20-S35
4.468.2
EPFR20-S35__ - __ __ __ - __ - __ __
Bias Spring
80 5.5 bar (80 psi)
160 11 bar (160 psi)
Option
None
(Blank)
Seals
N Buna N (Std.)
V Fluorocarbon
P Polyurethane
(for pressures over
240 bar/3500 psi)
®
HYDRAFORCE
HYDRAFORCE
.com
®
Load-Sense Drain Flow Control
Ductile iron bodies are
available for pressures up
to 350 bar (5000 psi).
Cartridge: Weight: 0.77 kg. (1.7 lbs.)
Steel with hardened work surfaces.
Zinc-plated exposed surfaces.
Buna N O-rings and polyester
elastomer back-ups standard.
Standard Ported Body: Weight:
1.65 kg. (3.65 lbs.) Anodized high-
strength 6061 T6 aluminum alloy,
rated to 207 bar (3000 psi). Ductile
iron bodies available; dimensions
may differ. See page 8.020.1.
MATERIALS
Porting
Cartridge Only 0
SAE 16 w/SAE 6 Pilot Port 16T
Blue rectangles are links to other catalog pages.
