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VFD120 Series
Variable Priority Flow Dividers
Aimed at mobile and industrial applications the VFD120 can
be used for controlling hydraulic motor and cylinder speeds by
manually adjusting the flow rate.
Variable priority flow dividers split a single input (P) flow into a
priority (REG) flow and an excess or by-pass (BP) flow which can
be returned directly to the oil reservoir or used to power a second
system. This is possible due to the valve’s adaptive pressure
compensation characteristics meaning both the priority and by-
pass flows can be used to drive separate circuits, even under
varying loads. In many instances this dispenses with the need for
another pump to operate a second system.
The VFD120 design has also been optimised to reduce energy
wastage by minimising the pressure losses across the valve,
resulting in a significant reduction in running costs.
Specications
Maximum Rated Pressure: Up to 420 bar, 6000 psi
Total Flow: Up to 120 L/min, 32 US gpm
Maximum Priority (REG) Flow: Up to 95 L/min, 25 US gpm
Fluid Temperature Range: -30 to 120 °C, -22 to 248 °F
Ambient Temperature Range: -30 to 50 °C, -22 to 122 °F
Porting: BSPP, SAE, NPT, METRIC
Material: Steel components in cast Ductile Iron body painted black
Aluminium knob
Weight: Typically 2.0 kg, 4.4 lb
Mounting: 2 Bolts - M8 or 5/16”
Features
● Clearly marked single-turn
hand dial permits fast
visual adjustments to pre-
determined ‘Priority’ flow.
● Pressure compensated
permitting both ‘Priority’
and ‘By-Pass’ to be used
simultaneously at varying
pressures without affecting
the ‘Priority’ flow rate.
● Anti-tamper locknut option
available. Contact Sales
Office for more informa-
tion.
● Reverse flow capable (De-
pending upon control knob
position) Contact Sales
office for more information.
VFD120-BU-ENG-3376.pdf - 10/24 - ISSUE 4.0
Symbol:
IN
BP
REG
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Table 1: Valve Type
CODE DESCRIPTION
RD Standard
LN Lock Nut Version
Table 2: Priority (REG) Flow Capacity*
CODE FLOW SIZE
L/min US GPM
030 0 -11 0 - 3
050 0 - 19 0 - 5
080 0 - 30 0 - 8
120 0 - 45 0 - 12
160 0 - 60 0 - 16
200 0 - 76 0 - 20
250 0 - 95 0 - 25
Use for Lock Nut Version Only
X??** ?? L/min
Notes:
* Input flow will affect the maximum seen
priority flow capacity. To achieve the given flow
capacity, the input flow needs to be greater.
** Unless otherwise stated, factory set to 47 L/
min (CODE X47).
VFD120-BU-ENG-3376.pdf - 10/24 - ISSUE 4.0
Sales Order Code
Please contact our technical sales team to discuss any special order requirements.
TYPICAL CODE DESCRIPTION SEE TABLE YOUR CODE
VFD120 Basic Valve -
RD Valve Type Table 1
120 Priority (REG) Flow Capacity Table 2
J Porting Table 3
Table 3: Porting
CODE PORT THREAD TYPE
H 1/2” BSPP ***
J 3/4” BSPP
G 1-1/16” -12UN # 12 SAE ORB
A 3/4” NPTF ****
M M22 X 1.5 ***
Notes:
*** M22 and 1/2” BSPP threads only available in flow
codes 030 to 120.
**** All NPTF threads are to ANSI B1.20.3 -1976 Class
1. As stated in the standard it is recommended that
“sealing is accomplished by the means of a sealant
applied to the thread”. NPT fittngs may also be used to
connect to NPTF ports (also with a sealant applied to
the thread).
Priority (Reg) Flow vs. Load
Flow L/min
Pressure BAR
Priority > Bypass
Priority > Bypass
0
10
20
30
50
40
60
70
80
90
100
-200 -150 -100 -50 0 50 100 150 200
All tests completed using ISO32 Mineral oil at 40 degrees C (32 cSt)
120 L/min Input Flow
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HEIGHT REDUCED BY 7mm
WHEN USING LOCKNUT OPTION
VFD120-BU-ENG-3376.pdf - 10/24 - ISSUE 4.0
Installation Details Dimensions in mm [inches]
Max Pressure Drop Between Inlet (P) and priority (REG) port
Inlet Flow - 120 L/min, REG port 100 Bar, BP port to tank
LN (Anti-Tamper Locknut Option)
Select Sales Order Code ‘LN’
from Table 1 ‘Valve Type’.
State flow setting required,
otherwise factory setting is used.
030
160
200
250
050
080
120
10
20 30 40 50
60
70
80 90
100
26.4
23.8
21.1
18.5
15.9
13.2
10.6
7.9
5.3
2.6
17.0
9.0
11.0
13.0
15.0
246.6
217.6
188.5
159.5
130.5
78
3.07
46
1.81
49.5
1.95
39
1.54
23.6
0.93
63
2.49
2 MTG HOLES
Ø8.5 (0.33") THRU'
35.9
1.41
62.7
2.47
95
3.73
21
0.83
PRIORITY
(REG)
INPUT
(P)
135
5.30
60
2.35
21
0.83
BYPASS
(BP)
THIRD ANGLE PROJECTION
Pressure BAR
Priority (REG) Flow L/min
Priority (REG) Flow US GPM
Pressure PSI
All tests completed using ISO32 Mineral oil at 40 degrees C (32 cSt)
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Circuit Suggestions
1. Variable Speed of Hydraulic Motor Drive on Agricultural Tractor
This circuit gives the capability to vary the speed of a hydraulic motor as required. Also, for a given control knob setting, the hydraulic motor
speed stays constant regardless of the tractor speed.
Circuit 1
Circuit Suggestions
2. Two Circuits From a Single Pump
Using only one pump, this circuit gives speed control of the hydraulic motor and powers a hydraulic cylinder. Each function can be used
either simultaneously or independently because pressure variations between priority (REG) and By-Pass (BP) flows do not effect the flow
on the priority (REG) circuit.
Circuit 2
Circuit Suggestions
3. Multiple Circuits From a Single Pump
Using one pump, this circuit gives independently variable speed drive from three hydraulic motors. Motors can be used simultaneously or
independently.
Circuit 3
VFD120-BU-ENG-3376.pdf - 10/24 - ISSUE 4.0
Webtec
®
reserve the right to make improvements and changes to the specification without notice
Webtec
®
, Make it BLUE
®
, FlowHUB
®
, ViscoCorrect
®
, Interpass
®
and QuickCert
®
are registered trademarks of Webtec Products Limited.
