Valves - Pressure Controls - Relief Valve - Crossover

CR08-28

BIDIRECTIONAL RELIEF VALVE

Overview

Description

The CR08-28H is a screw in, cartridge style, direct acting, differential area, poppet type, internally vented, bidirectional hydraulic relief valve intended for use as a pressure limiting device for common hydraulic circuit protection

Operation

The CR08-28H blocks flow from either port 1 or port 2. On attainment of a predetermined pressure at either port 1 or port 2, the spring-opposed poppet is forced from its seat. The cartridge offers fast response to load changes in typical hydraulic circuits requiring low hysteresis, low pressure rise and low internal leakage

Features

  • Factory preset hidden adjustment.
  • Pressure setting range of 138-276 bar (2000-4000 psi)
  • Corrosion-protection of 960 hours salt spray per ASTM B117.
  • Hardened parts for long life.
  • Industry common cavity.

Ratings

Pressure Ratings
Pressure rating
276 bar (4000 psi)
Proof pressure
689.7 bar (10000 psi)
Burst pressure
827.6 bar (12000 psi)
Crack pressure defined
Pressure evident at 0.95 lpm (0.25 gpm)
Reseat pressure
Nominal 85% of crack pressure leakage to
1 ml/min (20 drops/min)
Flow Ratings
Flow rating
37.9 lpm (10 gpm)
Maximum internal leakage
1 ml/min (20 drops/min)
Temperature Ratings
Maximum operating fluid 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 225 °F) With polyurethane seals
Storage temperature
-40 to 70 °C (-40 to 160 °F)
Ambient temperature
-40 to 70 °C (-40 to 160 °F)
Other Ratings
Corrosion protection
960 hr salt spray per ASTM b117

Operating Parameters

Fluids
Mineral based or synthetic with lubricating properties
Fluid viscosity range
7.4 to 420 cSt
Maximum operating contamination level
18/16/13 per ISO 4406

Properties

Cartridge weight
0.24 kg (0.52 lb)
Internal wetted surface area
167 cm² (25.9 in²)

Performance

CR08-28H_Flow-Pressure

Dimensions

CR08-28H_Dim

Materials

Materials

Cartridge: Weight: 0.24 kg (0.52 lb). Steel with hardened work surfaces. Zinc-plated exposed surfaces.

Standard Ported Body: Weight: 0.63 kg (1.38 lb). Ductile iron, rated to 350 bar (5075 psi). Aluminum body available; weight and dimensions may differ.

Installation Specifications

Cavity
VC08-2
Cartridge installation torque
25.8 to 28.5 N-m (19 to 21 ft-lb)
H style plug torque
34 to 40.7 N-m (25 to 30 ft-lb)
Orientation restriction
None

Accessories

Seal kit
SK08-2X-M X = seal option

Order code

POSITION
CODE
DESCRIPTION
CR08-28F-H-J-R/S
F
Adjustment Option
F
A
1/4" Hex Allen Head
F
B
1-1/2" Diameter Aluminum Knob with Aluminum Lock Knob
F
C
1/4" Hex Allen Head with Cover Cap
F
F
Factory Preset Non-Adjustable
F
H
Factory Preset Hidden Adjustment
F
L
1/4" Hex Allen Head with Cover Cap and Lockwire Holes
H
Line Body
H
0
No Body
H
4T
Aluminum SAE 4
H
6T
Aluminum SAE 6
H
8T
Aluminum SAE 8
H
6TD
Ductile Iron SAE 6
H
8TD
Ductile Iron SAE 8
H
2B
Aluminum BSPP 1/4" (2)
H
3B
Aluminum BSPP 3/8" (3)
H
3BD
Ductile Iron BSPP 3/8" (3)
J
Seal
J
N
Buna-N
J
V
Fluorocarbon
J
P
Polyurethane
J
U
PPDI Urethane
R
Spring
R
40
137.9 to 275.9 bar (2000 to 4000 psi) Spring Range
S
Setting
S
MXXX
Spring Setting in XXX bar
S
XX
Spring Setting in XX psi (x 100)