HYDAC FPS Series - Manual (Page 5)

5 Charging & Gauging Units
PN#02068202
• ACU1107-1367 / 09.11
ACCUMULATORS
Pressure Increase
When charging an accumulator that has
an existing gas precharge, allow 5 to 10
minutes for the gas temperature and thus
pressure to stabilize.
FPS Unit
Turn T-handle clockwise until the gauge
needle begins to deflect, then turn it another
full turn. Proceed to “Filling”.
FPK Unit
Turn T-handle counter clockwise until the
gauge needle begins to deflect, then turn it
another full turn. Proceed to “Filling”.
FPK Unit (with adapter FPK/SB)
Turn T-handle clockwise until the gauge
needle begins to deflect, then turn it another
full turn. Proceed to “Filling”.
Filling
Open the shut-off valve on the commercially
available nitrogen bottle and slowly fill the
accumulator with dry nitrogen gas.
Precharge very slowly until the pressure
in the accumulator reaches 100 psi. Once
100 psi is reached, the charging rate can
increase. Charging too quickly may damage
the accumulator.
Note: The gauge registers the line pressure,
not necessarily the accumulator pressure
while charging.
After allowing the appropriate time for
the gas temperature and thus pressure to
stabilize, adjust the gas precharge pressure
as required, refer to “Pressure Increase” (see
page 4) or “Pressure Release” (see page 3) .
Once the desired gas precharge pressure
is reached close the shutoff valve on the
commercially available nitrogen bottle.
Remove the charging and gauging unit from
the gas valve as described under “Removal
of Charging and Gauging Unit” (see page 5) .
Removal of Charging and
Gauging Unit
Close the shut-off valve on the commercially
available nitrogen bottle before removing
the charging and gauging unit.
FPS Unit
Turn T-handle counter clockwise until
resistance is felt to close the gas valve.
Open manual bleed valve to relieve pressure
in the charging and gauging unit. Proceed to
“Disconnecting”.
FPK Unit
Turn T-handle clockwise until resistance
is felt to close the socket head cap screw,
hand tighten. Open manual bleed valve to
relieve pressure in the charging and gauging
unit. Proceed to “Disconnecting”.
FPK Unit (with adapter FPK/SB)
Turn T-handle counter clockwise until
resistance is felt to close the gas valve.
Open manual bleed valve to relieve pressure
in the charging and gauging unit. Proceed to
“Disconnecting”.
Disconnection
Unscrew the charging and gauging unit
from the gas valve. Note: For FPK unit with
adapter FPK/SB it may be necessary to
loosen the connection between cap nut
and the adapter to remove the charging
and gauging unit. Check for leaks. None are
permissible.
Completion
HYDAC gas valve version 1
(see fig. 1)
Tighten socket head screw cap to 20 Nm
(15 lb-ft), and screw on valve protection cap
(where applicable) ; hand tighten.
HYDAC gas valve version 4
(see fig. 1)
Screw on valve seal cap torquing to 30 Nm
(22 lb-ft), and valve protection cap (where
applicable) ; hand tighten.