NPK DG16 - Replacement of the Seals in the Rotary Joint

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ROTARY JOINT MAINTENANCE
TESTING THE ROTARY JOINT SEALS FOR INTERNAL
LEAKAGE
PROCEDURE
Install a 0 – 5,000 psi gauge (g8f) in the NPK shut-off (k4) located on the stick of the
carrier. Close the arms and keep the function activated and read the pressure.
Compare the pressure reached with the specifications for your model Demolition Grab
(GZ). If the proper relief pressure cannot be reached, you must disassemble the rotary
joint to check for failed seals.
REPLACEMENT OF THE SEALS IN THE ROTARY JOINT
The arms (dg1 and dg2) of the Demolition Grab should be opened and safety bar (t79)
installed during repair. Close the NPK shut-off valves on the stick of the carrier.