HYDAC International SB 330 Notice D'utilisation page 32

4. Commissioning
NOTICE
Bladder accumulators must be charged with
nitrogen. Check before commissioning (see
section 5.3).
The hydraulic accumulator must be checked
for corrosion.
Before commissioning and after charging the
hydraulic accumulator to the required pre-
charge pressure, check that the connections
on the fluid and gas sides are tightened
to the correct torque, and tighten further
if necessary. It must be ensured that no
attachment parts become twisted.
For tightening torques, see fold-out page.
The closing elements on the fluid side that
serve as transport protection must be removed.
The min./max. operating data is permanently
marked on the hydraulic accumulator. The
marking should be kept in a legible condition.
EN
If venting is required, this must be done on
the oil-side connection prior to commissioning
the bladder accumulator, by opening the vent
screw (item 19) located on the oil valve.
4.1 Pre-charge pressure
Hydraulic accumulators are supplied with a
transit pressure (less than 2 bar) or with a
pre-charge pressure defined with the order (p
The pre-charge pressure (p
label on the accumulator shell, or stamped on
the accumulator body or engraved on the type
code label.
The level of the pre-charge pressure (p
corresponds to the operation of the system.
This must be checked by the owner before
commissioning and corrected as necessary.
Critical values of the pre-charge pressure
p ≤ 0.9 • p (p
0 1
Permitted pressure ratio: p
32
) is indicated on a
0
= minimum operating pressure)
1
: p ≤ 4:1
2 0
4.2 Charging gas
In principle, only use nitrogen of at least
Class 4.0 (99.99 %). Deviations from these
specifications must be agreed with HYDAC.
4.3 Charging the hydraulic
accumulator
The HYDAC FPU charging and testing
unit must be used to charge the bladder
accumulator.
The max. operating pressures of the FPU must
be observed:
FPU-1: 350 bar
FPU-2: 800 bar
The charging and testing unit is supplied with
detailed operating instructions, see:
"Instruction manual for charging and testing unit
FPU"
No. 3.501.BA
During the charging process the hydraulic
accumulator must be securely mounted.
4.4 Permitted operating
temperatures
The permitted operating temperature is
).
0 determined by the material of the accumulator
shell, valve and bladder and is indicated on the
name plate and the documentation.
4.5 Permitted operating pressure
)
The permitted operating pressure is determined
0
by the material of the accumulator shell and
valve and is indicated on the name plate and
the documentation.
4.6 Hydraulic fluids
Hydraulic accumulators must only be operated
with pressure fluids with a minimum cleanliness
class of:
– NAS 1638 Class 6 or
– ISO 4406 Class 17/15/12
Hydraulic accumulators must only
be charged with nitrogen.
Never use other gases.
Risk of explosion!