NPK GH10, Operator'S Manual

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NPK
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HYDRAULIC INSTALLATION
HYDRAULIC QUICK DISCONNECTS
NPK recommends against the use of non-NPK quick disconnects on
hydraulic circuits operating NPK Products.
1. The hydraulic pulsations caused by hydraulic hammer operating can cause internal
pieces of non-NPK quick disconnects to disintegrate. These pieces would migrate
into the hammer, causing damage.
2. If quick disconnects are used when the hammer is removed from the excavator, the
quick disconnects should be capped to keep them clean. If this is not done,
contamination on the disconnect will be flushed into the hammer when re-connected.
This, again, can cause damage.
3. Most quick disconnects create a restriction in the circuit. NPK Hammers are not
back pressure sensitive, but restrictions cause unnecessary heating of the oil. Also,
the pressure required to operate the hammer, plus the restriction of the disconnects
may push an older, low pressure, carrier machine to the limit of its hydraulic system.
This would interfere with proper hammer operation.
However, the NPK approved
quick disconnects are properly sized so that the hammer operation is not
affected.
NOT RECOMMENDED CONNECTION
APPROVED CONNECTION (39) Non-NPK Quick Disconnects (32)
NPK APPROVED CONNECTION QUICK DISCONNECTS (DX)
CONTACT YOUR NPK DEALER FOR ADDITIONAL INFORMATION ABOUT
NPK QUICK DISCONNECTS