MTS Series 111 Accumulator - Manual (Page 37)

6.4.0 Purge Fluid from the Gas Chamber
Piston-type accumulators may collect hydraulic fluid in the gas chamber, which then reduces the gas volume
of the accumulator. The fluid should be purged from the gas side if a pressure check procedure shows one
or more of the following:
• A consistent trend of pressure being higher than expected.
• Precharging requires smaller volumes of gas than expected to obtain a desired pressure level.
• Fluid is expelled from a gas valve during gas venting.
Caution:
Venting pressurized gasses can generate loud noises and freezing temperatures.
Transferring gasses from high to low pressure containers creates freezing temperatures.
Do not work with pressurized gasses without wearing protective clothing. Wear heavy gloves,
safety glasses, and ear plugs when working with pressurized gases.
1. If the valve stem of the accumulator is facing down, go directly to Step 2. If the valve stem of the accumulator
is facing up or the accumulator is on its side, remove the accumulator as described in “Remove the
Accumulator” and turn it so that the valve stem is facing down.
2. Remove the accumulator valve protective cover and the valve stem cap. Securely position the accumulator
with the gas valve down.
3. Place a suitable container under the valve stem to capture any expelled fluid. Use an open-end wrench
and open the locknut on the accumulator valve assembly two or three full turns. Allow gas pressure to
reduce to zero and any hydraulic fluid to be expelled.
4. Replace the accumulator as described in the Installation chapter. Then precharge the accumulator as
described in “Change the Precharge Pressure.”
Series 111 Accumulator Product Information 37
6.0 Maintenance