Figure 4: Joints of successive packing should be
staggered at 90°. When enough rings have been
installed so that the nose of the gland will reach
them, individual tamping should be supplemented by
using the gland.
5. After the last ring is installed.
Put the gland in place and take up bolts finger
tight or very slightly snugged up. Do not jam
packing into place with excessive
gland loading. Start the pump and take up bolts
until leakage is decreased to a tolerable minimum.
Make sure gland bolts are adjusted evenly.
Stopping leaking entirely at this point will cause
the packing to burn up.
6. Allow packing to leak freely when starting up a
newly packed pump.
Excessive leakage during the first hour of operation
will result in a better packing job over a longer
period of time. Take up gland bolts gradually as the
packing seats to a tolerable level of 10 to 12 drops
per minute per inch of shaft diameter.
Never try to stop leakage entirely, unless packing
manufacturer indicated that it is safe to do so.
7. When specified by the pump manufacturer, provide
means of lubricating the shaft and the packing
through the lantern ring by supplying water, oil,
grease or liquid handled in the pump.
Fittings for this purpose are standard on many
pumps.
8. If the stuffing box has a lantern ring
, make sure that the lantern ring, as installed, is
slightly behind the fluid inlet so that it will move
under the inlet as the follower pressure is
applied.See Figure 5
9. On both centrifugal and reciprocating pumps,
about 70% of wear is on the outer two packing rings
nearest the gland. However, each additional ring
does throttle some fluid pressure. On most
equipment, there must be enough rings so if one
fails, another does the sealing, and the machine
need not be shut down.
Installation of SEPCO's Patented Spiral Pack
Packing:
Warning:
Never wind bulk or coiled packing into the stuffing
box. Cut the packing into separate rings before
installation. Use the same procedure of installing
rings outlined in Steps 1-9.
Installation of PTFE 8 Graphite Yarn Packing:
Warning:
Seat rings gently, the gradually tighten bolts after
pump is on stream. Use the same procedure of
installing rings outlined in Steps 1-9.
>>The End
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