Checking The Pre-Charge Pressure; Deinstallation Of The Bladder Accumulator - Freudenberg BA 15-B02 000/18 Instrucciones De Operación

6.2. Checking the pre-charge pressure

Checking the nitrogen pre-charge pressure and comparing the actual and set value allows conclusions to be
drawn about the condition of the bladder as well as a monitoring of the gas losses due to permeation over the
operating time.
The following main steps must be carried out to check the pre-charge pressure of the bladder accumulator:
•
Ensure system-side pressure relief.
•
Remove the outer protective cap and the inner valve cap at the gas port of the bladder accumulator.
•
Close the drain valve/plug of the filling and testing device.
•
Assembly of the filling and testing device on the gas valve body of the bladder accumulator.
(Detailed procedure can be found in the operating manual of the filling device)
•
Slowly open the gas valve by operating the filling and testing device.
(Detailed procedure can be found in the operating manual of the filling device)
•
If necessary, wait for the gas temperature compensation. Read the indicated pre-charge pressure.
•
Determine and evaluate the difference between actual and set pressure of the nameplate.
Refilling the bladder accumulator to its nominal pre-charge pressure is generally recommended as part of the
annual servicing. If the detected pressure loss is low and the efficiency of the accumulator is still sufficient for
the application, refilling can be refused, as long as the following operating criteria are met.
Max. allowable pressure ratio:
Max. allowable pressure range:
•
Refill the bladder to the accumulators set pressure if mendatory.
•
Disassemble the filling and testing device from the gas valve body of the bladder accumulator.
(Detailed procedure can be found in the operating manual of the filling device)
•
Check for nitrogen leakage at the gas valve.
•
Screw on and tighten the valve cap.
•
Mount the protective cap on the gas port of the accumulator.

6.3. Deinstallation of the bladder accumulator

For repairs and recurring inspections it is necessary to uninstall the bladder accumulator. Special care must be
taken in this regard. The following main steps must be carried out within the deinstallation process..
•
Ensure pressure relief of the system and of any residual pressure in the accumulator.
•
Remove the valve cap and mount the filling device on the gas valve body of the bladder accumulator.
•
Carefully relief the nitrogen pre-charge pressure.
CAUTION: When the gas is relieving, the nitrogen concentration in the environment of the bladder
accumulator increases. Adequate ventilation in closed rooms must therefore be ensured .
CAUTION: During the expansion of a gas, its temperature drops. This may result in a significantly
reduced surface temperature of the vessel, but definitely of the gas valve as well as the filling and
testing device. Touching these surfaces during or immediately after the gas relief may lead to
injury.
•
Wait for temperature compensation of the super cooled components and release any residual gas
pressure that may have built up.
•
Disassemble the filling and testing device.
•
Screw on the inner valve and outer protective cap.
•
Fasten the bladder accumulator in a lifting device using lifting straps or slings.
•
Disconnect the oil port from the system side fluid line and uninstall the accumulator.
∆
and
32