PRESSURE CONTROLS
PR58-38 Pressure Reducing/Relieving Spool Valve
DESCRIPTION
A screw-in, cartridge-style, direct-acting, spool-type, hydraulic pressure reducing/
relieving valve, with internal pilot and internal spring-chamber drain. It is designed to
act as a pressure regulating valve for secondary circuits. Internal damping makes this
valve particularly suitable for use in circuits with unstable input flows in demanding
applications requiring enhanced stability.
OPERATION
In its steady state, the PR58-38 allows flow to pass bidirectionally from port 2 to port
1, with the spring chamber constantly drained at port 3. Upon attainment of a prede-
termined pressure at 1, the spool shifts to block flow at 2, thereby regulating pressure
at 1. In this mode, the valve will also relieve from port 1 to port 3, at a user-specified
value over the set reducing pressure. Tank port pressure is additive to the pressure
setting at a ratio of 1:1.
FEATURES
• Adjustments cannot be backed out of the valve.
• Adjustments prohibit springs from going solid.
• Optional spring ranges to 248 bar (4200 psi).
• Optional 233 micron screen.
• Hardened parts for long life.
• Industry common cavity.
RATINGS
Maximum Operating Pressure: 345 bar (5000 psi)
Proof Pressure: 379 bar (5500 psi)
Burst Pressure: 896 bar (13000 psi)
Regulated Pressure Range: 10.3–220.6 bar (150–4200 psi)
Note: 241 bar (3500 psi) maximum for ‘F’ and ‘H’ adjustment options.
Maximum Tank Port Pressure: 68.9 bar (1000 psi)
Maximum Rated Flow: 18.9 lpm (5 gpm); See performance chart
Maximum Internal Leakage to Port 3: 82 ml/minute (5.0 cu. in./minute)
Temperature: -40 to 100°C (-40 to 212°F) with Buna N seals;
-26 to 204°C (-15 to 400°F) with fluorocarbon seals;
-54 to 107°C (-65 to 224°F) 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: VC08-3; See page 9.108.1
Cavity Tool: CT08-3XX; See page 8.600.1
Seal Kit: SK08-3X-BM; See page 8.650.1
USASI/ISO:
SYMBOLS
PERFORMANCE (Cartridge Only)
6.450.1
345/5000
276/4000
207/3000
138/2000
11.4
3
7.5
2
3.8
1
0 11.4
3
FLOW lpm/gpm
PRESSURE bar/psi
Maximum Setting for All Springs
32 cSt/150 sus oil at 40°C
7.5
2
3.8
1
Relieving 1 to 3 Reducing 2 to 1
69/1000
15.1
4
18.9
5
15.1
4
18.9
5
Typical Relieving and Reducing Pressure vs. Flow
3300 psi spring
4200 psi spring
2050 psi spring
550 psi spring
2
3
1
8.6/125
6.9/100
5.2/75
3.4/50
1.7/25
11.4
3
7.5
2
3.8
1
0 11.4
3
FLOW lpm/gpm
PRESSURE bar/psi
Fully Open Pressure Drop
32 cSt/150 sus oil at 40°C
7.5
2
3.8
1
Relieving 1 to 3 Reducing 2 to 1
15.1
4
18.9
5
15.1
4
18.9
5
Screen
No Screen
HYDRAFORCE
.com
®
Relief setting in bar
†
(Blank) for Adjustable, or
Specify, for example:
M25 25 bar
M100 100 bar
Relief setting in psi
†
(Blank) for Adjustable, or
Specify, for example:
10.0 1000 psi
23.5 2350 psi
TO ORDERMATERIALS
Cartridge: Weight: 0.28 kg. (0.61 lbs.)
maximum (some models may weigh
less). Steel with hardened work
surfaces. Zinc-plated exposed
surfaces. Buna N O-rings and
TFE back-ups standard. Anodized
aluminum knob.
Standard Ported Body: Weight:
0.27 kg. (0.60 lbs.) Anodized
high-strength 6061 T6 aluminum
alloy, rated to 207 bar (3000 psi),
dimensions may differ. Ductile iron
(code D) bodies are required for
operation over 207 bar (3000 psi).
See page 8.008.1
Note: Orifice Disc should not be
used with this valve.
Porting
Cartridge Only 0
SAE 6 6T
SAE 6 6TD
1/4 in. BSP* 2B
1/4 in. BSP* 2BD
3/8 in. BSP* 3B
3/8 in. BSP* 3BD
*BSP Body; U.K. Mfr Only
Seals
Buna N (Std.) N
Fluorocarbon V
Polyurethane P
1,000 Hour
Salt Spray Coating G
Spring Range
05 10.3 to 37.9 bar
(150 to 550 psi)
20 34.5 to 141.4 bar
(500 to 2050 psi)
32 55.2 to 220.6 bar
(800 to 3300 psi)
42 17.2 to 248.2 bar
(3301 to 4200 psi)
†
Adjustable valves will be
preset to approx. 50% of
spring max. potential, unless
specified.
DIMENSIONS
__PR58-38__ - __ - __ __ __ - __ - __ __ / __ __ __ __
Adjustment Option
1/4 in. Hex Allen Head A
1-1/2 in. Dia.
Alum. Knobs B
Option A with Cover Cap C
Factory Preset Non-Adj. F
Factory Preset;
Hidden Adjustment H
Option C
w/Lockwire Holes L
PR58-38
6.450.2
2.75
69.9
0.28
7.1
0.28
7.1
0.28
7.1
2.00
50.8
2.12
53.8
0.61
15.5
1.17
29.8
Thru
2 Places
TORQUE:
25 ft-lbs (33.9 Nm)
max.
1.25
31.8
1.28
32.5
2.56
65.0
Ductile iron
body shown
Damped, Direct-Acting
Note: Polyurethane
seals are required for
operation over 241
bar (3500 psi).
Note: 241 bar/3500 psi max. for
F and H adjustment options.
®
HYDRAFORCE
HYDRAFORCE
.com
®
Screen Option
None (Blank)
233μ on Inlet Port 2 S
Blue rectangles are links to other catalog pages.
