Pressure Control Valves

PR50-38 — Pressure Reducing/Relieving Spool Valve, High Pressure, Damped, Direct-Acting
  Selection guide - similar valves.
  PDF file of this page.
  STP file for PR50-38.
  Request a quote.

PR50-38 Valve

PR58-38 Valve symbol

A screw-in, cartridge-style, direct-acting, spool-type, hydraulic pressure reducing/relieving
valve with internal spring-chamber drain and spool damping chamber. It is designed to act
as a pressure-regulating device for secondary circuits. Internal damping makes this valve
particularly suitable for use in circuits with unstable input flows in demanding applications
requiring enhanced stability.

In its steady state, the PR50-38 allows flow to pass bidirectionally from 2 to 1, with the spring
chamber constantly drained at 3. On attainment of a pre-determined pressure at 1, the cartridge
shifts to block flow at 2, thereby regulating pressure at 1. In this mode, the valve also will relieve
1 to 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.

• Adjustments cannot be backed out of the valve.
• Adjustments prohibit springs from going solid.
• Optional spring ranges to 227.5 bar (3300 psi).
• Hardened spool and cage for long life.
• Industry-common size.

Maximum Rated Pressure at Supply Port: 345 bar (5000 psi)
at ports 1 and 2;
   241 bar (3500 psi) max for F and H Adjustment options
Proof Pressure: 48.2 bar (7000 psi) at ports 1 and 2;
   68.9 bar (1000 psi) at port 3

Burst Pressure: 1034 bar (5000 psi)
Standard Spring Ranges:
Spring code -5 -15 -21 -33
Adjustment range 10 to 38 bar
150 to 550 psi
7 to 103 bar
100 to 1500 psi
28 to 145 bar
500 to 2100 psi
55 to 228 bar
800 to 3300 psi
Adjustment per turn (F/H adjuster) 7.5 bar
(109 psi)
15.5 bar
(225 psi)
27.5 bar
(399 psi)
43.5 bar
(631 psi)
Adjustment per turn (A/B/C/L adjuster) 6 bar
(87 psi)
12.4 bar
(180 psi)
22 bar
(319 psi)
34.8 bar
(505 psi)
Note: It may be possible to adjust the valve either lower or higher than the nominal ratings shown. If the valve is adjusted beyond the recommended maximum pressure range for F and H style adjuster options, the valve may not open to relieve pressure.
Flow: up to 72 lpm (19 gpm); see performance chart
Internal Leakage: to port 3: 82 ml/minute (5 cu. in/minute) maximum
Temperature: -40° to 100°C (-40° to 212°F) with Buna seals;
   -26° to 204°C (-15° to 400°F) with Fluorocarbon seals;
   -54° to 107°C (-65°F to 225°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: VC10-3; See page 9.110_3w
Cavity Tool: CT10-3xx; See page 8.600.1
Seal Kit: SK10-3x-BM; See page 8.650.1


PR50-38  Performance Chart

PR50-38  Performance Chart

PR50-38 Valve Dimensions


Cartridge: Weight: 0.27 to
0.31 kg (0.59 to 0.69 lb) depending on adjustment type; 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: 0.36 kg (0.80 lb); Anodized high-strength 6061 T6 aluminum alloy, rated to 207 bar (3000 psi); Ductile iron (code ‘D’) bodies are required for operation over 207 bar
(3000 psi), dimensions may differ.
See page 8.010_3w.

Adjustment Option Details:
See page 6.003.1

PR50-38 Ordering Chart

Selection guide - similar valves.
PDF file of this page. STP file for PR50-38 Request a quote.