Eaton Vickers DG3V-8 Series Overhaul Manual page 12

3. Reducer Module (Fig 10): The reducer module is
required for piloted models when pilot pressure exceeds 210
bar (3000 psi). These two-stage spool valves maintain a
reduced outlet pressure against variations in inlet pressure.
These valves are able to act as relief valves (at 50% of the
maximum flow) to prevent excess pressure being developed
when an actuator is subject to a reactive load.
4. Fast Response Option: Some applications require the
main stage spool to shift at a faster than normal rate. For
such applications, the fast response option is used. This
option requires the removal of an orifice plug within the main
stage body. When the orifice plug is removed, larger volumes
of fluid will enter the pilot valve section. When the pilot valve
shifts, the main stage spool responds at a faster rate. However,
this also generates transients that increase system shock.
For this reason, the fast response option is not recommended
when pilot pressures exceed 210 bar (3000 psi). Fast
response models have the letter ''X'' stamped into the unit
nameplate (i.e. DG5V8-**X-**-M-**-10). Refer to catalog
5007.02/EN/0196/A for response time data. Figures 20 and
21 show the location of the orifice plugs that must be
removed for the fast response option.
16
8
9
10
14
11
12
13
15
Part No. Part Name
1 Plug
2 Back-up Ring
3 ''O'' Ring
4 ''O'' Ring
5 Spool
6 Body
7 Ball (2)
8 Spring Rest
9 Spring
Figure 10. Reducer Module
17
7
Part No. Part Name
10 Spring Rest
11 ''O'' Ring
12 Spring Housing
13 ''O'' Ring
14 Adjuster Housing
15 Adjuster
16 Nut
17 Dowel Pin
1
2
3
4
5
6
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