Gason NT8000, Operator'S & Parts Manual

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Maintenance & Service
21
Nordon Cylinders
This manual gives advice and procedures for disas-
sembling and servicing Hydraulic Cylinders manufac-
tured by Nordon Cylinders. It covers both NI and NIP
Phasing Cylinder ranges. The procedures should be
carried out by competent personnel, with the correct
tools.
Disassembly
Clean the cylinder body preventing contamination
and drain oil from the cylinder prior to commencing
any work. Hold the body of the cylinder securely in a
pipe vice, taking care not to distort the barrel. The rod end clevis can be left in place for all general
servicing. Using a C-spanner, unscrew the gland. It has a conventional thread, anti-clockwise to
loosen. Remove the Rod assembly (Rod, Gland and Piston) from the barrel.
Inspection of the Cylinder
Nordon Cylinders Phasing cylinders employ a
maintenance free bypass system. Re-phasing oc-
curs when the piston reaches full travel at either
end of the barrel. Oil is able to bypass over the
main seal via a small orifice port in the cylinder
barrel. This small orifice is located under the ex-
ternal port. Inspect, and blow compressed air
through the re-phasing orifices and port holes to
ensure there are no blockages.
Inspect the Piston seal for any signs of scoring or in-greased material which may indicate that foreign
matter may be present in the hydraulic system.
Inspect the general condition of the barrel’s internal surface; ensure it is free from scoring and con-
tamination. Any marks that can be felt using your finger nail will be detrimental to the seals. If the
barrel is damaged, a new cylinder will be required. The barrel is not a serviceable item and replace-
ment cost leads towards cylinder replacement.
Examine the rod for damage. Any marks that can be felt using your finger nail will be detrimental to
the seals. If the rod is damaged, a new rod, or rod assembly will be required. Examine all other parts
for signs of wear/damage particularly through the bore of the gland and piston.
Piston and Gland Removal
Removal of the piston should only be required if the gland seals need replacing. If required, follow
the steps below.