EATON Slip-in Cartridge Valve Catalog E-VLSC-MC002-E March 201278
Valvistor
®
Proportional Throttles
CVCS-**-HFV, 1* Series, Covers and CVI-**-HFV-A/B, 1* Series, Inserts
General Description
Eaton’s Vickers
®
HFV (Hydraulic Feedback Valvistor
®
) range of
slip-in cartridge valves uses a self-regulating hydraulic design
for the control of flow rate by a current-controlled PWM sig-
nal. The design achieves servo-type control of the main pop-
pet without using an electrical feedback transducer.
The construction and features of these valves open up a wide
range of applications with hydraulic cylinders and motors.
Such applications include ie casting, deep drawn presses,
injection molding, container handling, shovel loaders, forestry
and dump trucks. With the addition of HFV valves to the
established ISO 7368 (DIN 24342) cartridge valves, Eaton has
further enhanced an already comprehensive range.
Valvistor Technology
In “Valvistor” designs a main poppet amplifies a small flow
through the pilot circuit, comparable to a transistor. Thus
the name “Valvistor”, derived from “valve” and “transis-
tor”. Figures 39 and 40 show the construction of proportional
throttles to ISO 7368. In both cases a Vickers type KTG4V-3S
proportional valve is used as the pilot control valve. KBTG4V-
3S-EN427 (refer catalog V-VLDI-MS-04-E) & KBFTG4V-3S-
EN427 (refer catalog V-VLPO-MC007-E1) can also be used
as pilot valves. Hydraulic position feedback is obtained by
providing the main poppet with a longitudinal slot (5) in its
cylindrical surface. This slot, together with a metering edge
inside the sleeve, forms a variable orifice between the inlet
of the valve and the volume above the main poppet (3). When
the valve is closed and the main poppet is seated, the variable
orifice area is almost closed.
Figure 39
Construction for flow direction A to B; poppet in the closed
(no flow) condition. (Note: For flow A-B, poppet drilled from
A.)
Figure 40
Construction for flow direction B to A; poppet partially open.
(Note: For flow B-A, poppet drilled from B.)
Basic Characteristics
Nominal Sizes:
ISO 7368 DIN 24342
06 NG16
08 NG25
09 NG32
10 NG40
11 NG50
12 NG63
Maximum operating pressure ......................350 bar (5000 psi)
Flow ratings ............................. up to 2160 L/min (571 USgpm)
Catalog data based on pilot valve KTG4V-3S-EN427.
As the main poppet opens, the variable orifice area increases.
The slot is a part of one leg of a hydraulic bridge circuit and
provides an internal position feedback. With the pilot throttle
valve closed (figure 39), there is no pilot flow through the
closed-off slot in the seated poppet. The pressure above the
main poppet (3) is equal to the pressure at the valve inlet (1),
due to the controlled small opening at the variable orifice. As
the upper area of the poppet is greater than the area facing
the inlet (1), the poppet is held against its seat (6) by a force
proportional to the difference between valve inlet and outlet
pressures.
Opening the pilot throttle valve (figure 40) lowers the pressure
in volume (3) allowing the main poppet to move off its seat.
As this occurs the slot passes the metering edge (7), open-
ing the variable orifice and allowing flow through the pilot
circuit. Initially the flow through the pilot valve equals the
flow through the slot plus the volume displaced by the open-
ing movement of the main poppet. The main poppet moves
upwards until the pressure drops across the slot and the pilot
effects a force balance on the poppet. The poppet is then
held in a steady-state condition with equal flow across the
slot and the pilot.
If the flow through the pilot valve is reduced (by reducing the
command current to the solenoid), the force balance of the
main poppet is again disturbed and the main poppet moves
downwards reducing
the slot area and decreasing flow to the
upper chamber until the force balance is restored. Thus by
controlling flow through the pilot valve, the main poppet can
be controlled in any position from fully closed to fully open. In
this manner a very simple, effective servo-control of the main
poppet is obtained. If the outlet pressure exceeds inlet pres-
sure when the pilot valve is closed, the main poppet allows
reverse flow (see CVCS model code). The main valve function
is determined by the type of pilot fitted.
If pressure compensation is added to the pilot stage, the
complete valve is pressure compensated. If a pilot relief valve
is fitted, the main stage operates as a relief valve. As the pilot
flow is returned to the valve outlet (i.e. no “drain” connec-
tion) the valve is energy efficient. Therefore the position of
the main poppet is controlled by a closed-loop system with
a variable orifice in the poppet acting as the internal position
feedback element. The command signal in this feedback sys-
tem is pilot flow, as set at the proportional pilot throttle valve
(4).
6
5
4
1
2
Inlet A
3
Outlet B
7
1
2
3
4
Outlet A
Inlet B
7
6
General Description
Eaton’s Vickers
®
HFV (Hydraulic Feedback Valvistor
®
) range of
slip-in cartridge valves uses a self-regulating hydraulic design
for the control of flow rate by a current-controlled PWM sig-
nal. The design achieves servo-type control of the main pop-
pet without using an electrical feedback transducer.
The construction and features of these valves open up a wide
range of applications with hydraulic cylinders and motors.
Such applications include ie casting, deep drawn presses,
injection molding, container handling, shovel loaders, forestry
and dump trucks. With the addition of HFV valves to the
established ISO 7368 (DIN 24342) cartridge valves, Eaton has
further enhanced an already comprehensive range.
Valvistor Technology
In “Valvistor” designs a main poppet amplifies a small flow
through the pilot circuit, comparable to a transistor. Thus
the name “Valvistor”, derived from “valve” and “transis-
tor”. Figures 39 and 40 show the construction of proportional
throttles to ISO 7368. In both cases a Vickers type KTG4V-3S
proportional valve is used as the pilot control valve. KBTG4V-
3S-EN427 (refer catalog V-VLDI-MS-04-E) & KBFTG4V-3S-
EN427 (refer catalog V-VLPO-MC007-E1) can also be used
as pilot valves. Hydraulic position feedback is obtained by
providing the main poppet with a longitudinal slot (5) in its
cylindrical surface. This slot, together with a metering edge
inside the sleeve, forms a variable orifice between the inlet
of the valve and the volume above the main poppet (3). When
the valve is closed and the main poppet is seated, the variable
orifice area is almost closed.
Figure 39
Construction for flow direction A to B; poppet in the closed
(no flow) condition. (Note: For flow A-B, poppet drilled from
A.)
Figure 40
Construction for flow direction B to A; poppet partially open.
(Note: For flow B-A, poppet drilled from B.)
Basic Characteristics
Nominal Sizes:
ISO 7368 DIN 24342
06 NG16
08 NG25
09 NG32
10 NG40
11 NG50
12 NG63
Maximum operating pressure ......................350 bar (5000 psi)
Flow ratings ............................. up to 2160 L/min (571 USgpm)
Catalog data based on pilot valve KTG4V-3S-EN427.
As the main poppet opens, the variable orifice area increases.
The slot is a part of one leg of a hydraulic bridge circuit and
provides an internal position feedback. With the pilot throttle
valve closed (figure 39), there is no pilot flow through the
closed-off slot in the seated poppet. The pressure above the
main poppet (3) is equal to the pressure at the valve inlet (1),
due to the controlled small opening at the variable orifice. As
the upper area of the poppet is greater than the area facing
the inlet (1), the poppet is held against its seat (6) by a force
proportional to the difference between valve inlet and outlet
pressures.
Opening the pilot throttle valve (figure 40) lowers the pressure
in volume (3) allowing the main poppet to move off its seat.
As this occurs the slot passes the metering edge (7), open-
ing the variable orifice and allowing flow through the pilot
circuit. Initially the flow through the pilot valve equals the
flow through the slot plus the volume displaced by the open-
ing movement of the main poppet. The main poppet moves
upwards until the pressure drops across the slot and the pilot
effects a force balance on the poppet. The poppet is then
held in a steady-state condition with equal flow across the
slot and the pilot.
If the flow through the pilot valve is reduced (by reducing the
command current to the solenoid), the force balance of the
main poppet is again disturbed and the main poppet moves
downw
ards reducing the slot area and decreasing flow to the
upper chamber until the force balance is restored. Thus by
controlling flow through the pilot valve, the main poppet can
be controlled in any position from fully closed to fully open. In
this manner a very simple, effective servo-control of the main
poppet is obtained. If the outlet pressure exceeds inlet pres-
sure when the pilot valve is closed, the main poppet allows
reverse flow (see CVCS model code). The main valve function
is determined by the type of pilot fitted.
If pressure compensation is added to the pilot stage, the
complete valve is pressure compensated. If a pilot relief valve
is fitted, the main stage operates as a relief valve. As the pilot
flow is returned to the valve outlet (i.e. no “drain” connec-
tion) the valve is energy efficient. Therefore the position of
the main poppet is controlled by a closed-loop system with
a variable orifice in the poppet acting as the internal position
feedback element. The command signal in this feedback sys-
tem is pilot flow, as set at the proportional pilot throttle valve
(4).
6
5
4
1
2
Inlet A
3
Outlet B
7
1
2
3
4
Inlet B
7
6
General Description
Eaton’s Vickers
®
HFV (Hydraulic Feedback Valvistor
®
) range of
slip-in cartridge valves uses a self-regulating hydraulic design
for the control of flow rate by a current-controlled PWM sig-
nal. The design achieves servo-type control of the main pop-
pet without using an electrical feedback transducer.
The construction and features of these valves open up a wide
range of applications with hydraulic cylinders and motors.
Such applications include ie casting, deep drawn presses,
injection molding, container handling, shovel loaders, forestry
and dump trucks. With the addition of HFV valves to the
established ISO 7368 (DIN 24342) cartridge valves, Eaton has
further enhanced an already comprehensive range.
Valvistor Technology
In “Valvistor” designs a main poppet amplifies a small flow
through the pilot circuit, comparable to a transistor. Thus
the name “Valvistor”, derived from “valve” and “transis-
tor”. Figures 39 and 40 show the construction of proportional
throttles to ISO 7368. In both cases a Vickers type KTG4V-3S
proportional valve is used as the pilot control valve. KBTG4V-
3S-EN427 (refer catalog V-VLDI-MS-04-E) & KBFTG4V-3S-
EN427 (refer catalog V-VLPO-MC007-E1) can also be used
as pilot valves. Hydraulic position feedback is obtained by
providing the main poppet with a longitudinal slot (5) in its
cylindrical surface. This slot, together with a metering edge
inside the sleeve, forms a variable orifice between the inlet
of the valve and the volume above the main poppet (3). When
the valve is closed and the main poppet is seated, the variable
orifice area is almost closed.
Figure 39
Construction for flow direction A to B; poppet in the closed
(no flow) condition. (Note: For flow A-B, poppet drilled from
A.)
Figure 40
Construction for flow direction B to A; poppet partially open.
(Note: For flow B-A, poppet drilled from B.)
Basic Characteristics
Nominal Sizes:
ISO 7368 DIN 24342
06 NG16
08 NG25
09 NG32
10 NG40
11 NG50
12 NG63
Maximum operating pressure ......................350 bar (5000 psi)
Flow ratings ............................. up to 2160 L/min (571 USgpm)
Catalog data based on pilot valve KTG4V-3S-EN427.
As the main poppet opens, the variable orifice area increases.
The slot is a part of one leg of a hydraulic bridge circuit and
provides an internal position feedback. With the pilot throttle
valve closed (figure 39), there is no pilot flow through the
closed-off slot in the seated poppet. The pressure above the
main poppet (3) is equal to the pressure at the valve inlet (1),
due to the controlled small opening at the variable orifice. As
the upper area of the poppet is greater than the area facing
the inlet (1), the poppet is held against its seat (6) by a force
proportional to the difference between valve inlet and outlet
pressures.
Opening the pilot throttle valve (figure 40) lowers the pressure
in volume (3) allowing the main poppet to move off its seat.
As this occurs the slot passes the metering edge (7), open-
ing the variable orifice and allowing flow through the pilot
circuit. Initially the flow through the pilot valve equals the
flow through the slot plus the volume displaced by the open-
ing movement of the main poppet. The main poppet moves
upwards until the pressure drops across the slot and the pilot
effects a force balance on the poppet. The poppet is then
held in a steady-state condition with equal flow across the
slot and the pilot.
If the flow through the pilot valve is reduced (by reducing the
command current to the solenoid), the force balance of the
main poppet is again disturbed and the main poppet moves
downwards reducing the slot area and decreasing flow to the
upper chamber until the force balance is restored. Thus by
controlling flow through the pilot valve, the main poppet can
be controlled in any position from fully closed to fully open. In
this manner a very simple, effective servo-control of the main
poppet is obtained. If the outlet pressure exceeds inlet pres-
sure when the pilot valve is closed, the main poppet allows
reverse flow (see CVCS model code). The main valve function
is determined by the type of pilot fitted.
If pressure compensation is added to the pilot stage, the
complete valve is pressure compensated. If a pilot relief valve
is fitted, the main stage operates as a relief valve. As the pilot
flow is returned to the valve outlet (i.e. no “drain” connec-
tion) the valve is energy efficient. Therefore the position of
the main poppet is controlled by a closed-loop system with
a variable orifice in the poppet acting as the internal position
feedback element. The command signal in this feedback sys-
tem is pilot flow, as set at the proportional pilot throttle valve
(4).
6
5
4
1
2
Inlet A
3
Outlet B
7
1
2
3
4
Outlet A
Inlet B
7
6