socket tester after the desired proof-load has
been reached.
13. Open the choker valve (20) on the hand
pump, and close the external load-release valve.
WARNING
Never apply proof-loading with the lid
open, and keep hands clear of pin and
crosshead area.
14. Using the hand pump, pressurize the system
to increase the test load to 120,000 pounds. (See
step 17.) Hold the test pressure for 2 minutes.
15. As the pressure is gradually increased,
observe the cable for evidence of slippage. If the
cable begins to slip, proceed as follows:
a. Relieve the pressure as in step 2.
b. Remove the safety lock pin and open the
lid. It maybe necessary to first strike the lid with a
soft mallet before it can be slid forward to open.
c. Retract the wedges.
d. Remove the cable and clean it
thoroughly.
e. Clean and inspect the wedge gripping
surfaces. Replace the wedges if necessary.
f. Lubricate the wedge sliding surfaces.
g. Remove the cable from the socket tester
and examine the poured terminal.
16. Check the accuracy of the tension gauge
every 3 months. Test by applying a known hydraulic
pressure to the gauge that will indicate an
equivalent load reading.
REPLACING PACKINGS
The efficiency of any hydraulic gear is directly
dependent on the proper selection, preparation, and
installation of its packings.
The replacement
packings must be those called for in the assembly
parts list, and no deviation in size or substitution of
type is to be made. Natural or synthetic packings
are not used if overage, whether packed separately
or preassembled in a component. The age of a
packing can be determined from the expiration date,
which is stamped on the packing container. If the
expiration date is reached, is illegible, or is
otherwise in doubt, discard the packing.
Preassembled components having packings that
are overage are repacked with new packings before
replacement on the arresting gear. In no case are
packings used that arc more than 3 years old. The
packings are to be properly prepared by immersion
in the fluid used in the component being packed.
The two primary requirements of workmanlike,
efficient installation are the protection of sealing
edges, to ensure their perfect condition, and the
assembly of rings in their proper position. Scratches
or cuts caused by improper handling or by forcing
the packing over threads, sharp keyways, machined
edges, or burrs result in ultimate failure of the
packings because of leakage.
Removing Old Packings
If practical, remove the shaft, ram, or other
sealed members from the installation, since this
permits inspection and correction of any defects in
the shaft or packing assembly.
Although it is
preferable to remove the scaled member, limitations
of time, design of the installation, or problems of
reassembly often make the removal impractical.
After the gland or flange is removed, the chief
problem usually encountered is removing the female
adapter. If this ring is provided with holes, insert a
suitable hoop of bent and flattened wire, or a
threaded rod if the holes are tapped, and pull the
ring back along the shaft. The packing can be
removed using a U-shaped pick made of No. 12
copper or brass wire.
The pick should be small
enough to enter the stuffing box, and the ends
should be bent and flattened. The pick should be
inserted behind the ring, and the ring removed. It
is usually not necessary to remove the male adapter.
If the adapters are not provided with holes or if
removal is difficult, they may be removed by
alternate methods, such as inserting a wire or piece
of flat stock behind the adapter and pulling it out (if
sufficient space exists), or by bumping the shaft or
stuffing box to dislodge the adapter. All traces of
the packing must be removed and the stuffing box
cleaned and inspected for scratches, burrs, or sharp
edges. Rough spots or sharp edges must be honed
down with a fine Carborundum stone. It is usually
not necessary to replace the metal support rings or
adapters when packings are replaced unless
inspection shows failure, defects, or excessive wear.
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