Pressure Controls: Counterbalance, Sequence and Pressure Reducing Valves
DGMR(1)-3-4*
DGMX*-3-4*
General Description
These single-stage valves operate by
the application of pressure on the end of
the valve spool, acting against a spring
which is loaded by means of the
adjustment mechanism.
In the counterbalance and sequence
valves the spool is offset by the spring
such that flow cannot pass through the
valve. When the force exerted by the
pilot pressure on the spool end exceeds
the force of the main spring, the spool is
moved to allow flow through the valve.
In the pressure reducing valve the flow
path is normally open and is closed as
the pilot pressure exceeds the setting of
the valve. Excessive pressure in the
reduced-pressure line is prevented by a
pressure relieving function.
Pressure adjustment options of control
knob (with or without keylock) or
screw/locknut design are available.
Typical Section
Functional Symbols
PTBA
DGMR-3-TA
DGMR1-3-PP
DGMX*-3-PA
DGMX*-3-PB
DGMX*-3-PP
PTBA
PTBA
PTBA
PTBA
9
Model Code for Counterbalance, Sequence and Pressure Reducing Valves
DGM *(*) -3- ** (*) * 4*
1
1
2
*
3 4
5 6 7
Type
R = Counterbalance function
R1 = Sequence function
X1 = Pressure reducing, underlapped
X2 = Pressure reducing, overlapped
X3 = Pressure reducing, overlapped,
low leakage
Function ports
For DGMR only:
TA = Counterbalance control function in
“T” port, controlled by pressure in
“A” port
For DGMR1 only:
PP = Sequence control in “P” port,
controlled by pressure in “P” port
For DGMX only:
PA = Pressure reducing function in line
P, piloted from A
PB = Pressure reducing function in line
P, piloted from B
PP = Pressure reducing function in line
P, piloted from P
Adjuster location
Option on DGMX only
L = Adjuster at “A”-port end of valve
Blank = Adjuster at “B”-port end of valve
Pressure adjustment range
For DGMX only:
Y = 1,40-7,0 bar (21-101 psi)
R = 1,40-45,0 bar (21-652 psi)
For DGMR and DGMX:
A = 3-30 bar (43.5-435 psi)
B = 3,5-70 bar (51-1000 psi)
C = 10-140 bar (145-2000 psi)
F = 20-250 bar (290-3625 psi)
Pressure adjustment/ locking
method
H = Handknob
K = Micrometer with keylock
W = Screw and locknut
2
3
4
5
--*-
6
7
Gage port
B=G
1
/
8
I (
1
/
8
BSPF)
S = SAE 4 (
7
/
16
I-20 UNF-2B)
Design number, 40 series
Subject to change. Installation
dimensions unchanged for design
numbers 40 to 49 inclusive.
10
Typical performance with mineral oil at 21 cSt (102 SUS) and at 50_C (122_F).
0
bar
50 6040302010 L/min
0 4 8 12 16 USgpm
0
1000
psi
10
20
30
40
50
60
70
200
400
600
800
Reduced pressure setting
Q max.
DGMX*-3-P*
Low Pressure/Flow Rate Minimum Performance
Effect of Back-Pressure
The effective reduced pressure is equal
to the valve adjustment setting plus any
back-pressure in line T
Dead Head Leakage
Typical leakage flow at 250 bar inlet
pressure from reduced pressure line into
T at “Dead Head” condition (i.e. No flow
required at the reduced pressure outlet.)
This leakage flow must be provided at
the inlet line P in order to maintain the
reduced outlet pressure.
DGMX1-3 = 1600
DGMX2-3 = 400
DGMX3-3 = 80
300
250
200
150
100
50
0
bar
50 6040302010 L/min
0 4 8 12 16 USgpm
0
1000
2000
3000
4000
psi
Pressure
Flow rate
DGMR1-3-PP
300
250
200
150
100
50
0
bar
50 6040302010 L/min
0 4 8 12 16USgpm
0
1000
2000
3000
4000
psi
Pressure
Flow rate
DGMX*-3-P*
DGMX1-3
DGMX2-3
DGMX3-3
462
1020
0
Reduced pressure lineReverse flow to T line
Performance Characteristics
11
DGMR-3-TA-**-*-4*
DGMR1-3-PP-**-*-4*
DGMX(*)-3-P*(L)-**-*-4*
Models with type W adjuster
To adjust valve setting slacken off locknut and turn
adjuster screw
Turn clockwise to increase pressure;
counter-clockwise to decrease pressure.
Re-tighten locknut after completing adjustment.
DGMX2-3-**L models have adjuster and end
cap/gage port locations interchanged from positions
shown.
Installation Dimensions in mm (inches)
A
P
B
T
A
P
B
T
14 (0.55) max.
4 (
5
/
32
) A/F hex. socket
40
(1.57)
3,5 (0.14)
Ø3 (0.12 dia)
20
(0.79)
47,6
(1.87)
46
(1.8)
39 (1.54)
76 (3)
4 off “O” seals supplied for this mounting face4 holes through: Ø5,3 (0.21 dia)
12,7 (
1
/
2
) A/F hex. locknut
Torque to 25-30 Nm (18-22 lbf ft)
80 (3,1) max.
For gage port thread options see model code ,
(pressure plug fitted)
6
12
