Bosch Rexroth Corp., Model HAB..-7X,
RA 50175-B/07.2016
9 Charging the accumulator
9.1
Procedures
WARNING
Risk of Explosion
▶
USE only dry 99.99% pure nitrogen for charging accumulators.
▶
NEVER USE OXYGEN OR AIR, due to the risk of explosion.
1.
Close the drain valve on the charging and testing device and connect the hose to the
nitrogen bottle.
2.
Remove the valve guard and valve cap and screw the charging and testing device onto the
gas valve. More detailed information is provided in the instruction sheet furnished with the
charging and testing device.
3.
Open the gas shut-off valve on the nitrogen bottle and allow the gas to flow slowly into the
accumulator.
4.
Close the shut-off valve frequently and check the value of the precharge pressure on the
gauge.
5.
If the precharge pressure is too high, it may be reduced by opening the drain valve and
allowing some nitrogen to escape.
NOTE! The precharge pressure will vary depending on the gas temperature. Once the
desired precharge is reached, it is necessary to wait 2 minutes until the gas temperature
has equalized.
6.
Once again the precharge pressure needs to be checked and adjusted if necessary.
7.
Unscrew the charging and testing device and replace the valve guard and cap (see Fig. 1,
Item #1 & #2) A check for leaks with a soapy solution should follow. If a leak is found, it
should be repaired following recommended repair procedures.
8.
If the gas valve core is replaced, use only valve cores approved for accumulator service,
NOTE! NEVER USE AN AUTOMOTIVE TYPE VALVE CORE.
2
1
3
4
5
To System
Fig. 6: Typical circuit
22
Charging
1. Accumulator
2. Bleed automatic discharge valve
3. Check valve
4. Pump
5. Oil pressure gauge
