Rotech ANSI LTR, Инструкция по установке, эксплуатации и обслуживанию

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9. Replace packing when leakage cannot be controlled by
further take up on the gland.
Some of the most common reasons for packing
failure are:
• Improper installation
• Uneven gland adjustment
• Shaft misalignment and shaft whip
• Improper selection of packing for liquid
• Improper selection for pressure and temperature
• Contaminated liquid (dirt, abrasives, etc.)
• Operation without fluid
MECHANICAL SEALS
1. Blue the shaft sleeve Scribe a mark at the face of stem
plate to use as reference for installation of mechanical
seal.
2. Remove the impeller, shaft sleeve, and stem plate.
3. Install stationary seat of mechanical seal into seal
gland per seal manufacturer’s instructions.
4. Slide seal gland with stationary seat and seal gland
gasket onto shaft.
5. Install mechanical seal and locking collar onto shaft
sleeve per seal manufacturer’s instructions.
6. Install shaft sleeve with mechanical seal onto shaft.
7. Then mount stem plate to stem.
8. Reinstall impeller following same method previously
used.
9. Mount seal gland to stem plate.
Some of the most common reasons for seal
failure are:
• Improper installation
• Shaft misalignment and shaft whip
• Wrong selection for liquid pumped
• Dirt or grit between faces
• Seal gland tightened unevenly so stationary seat is not
perpendicular to shaft
• Operation without fluid
shaft sleeve. Hold the coil packing tightly and firmly on
the mandrel but do not stretch excessively. Cut the ring
and try it in the stuffing box to make certain it fills the
packing space properly with no gap in the joint at the
O.D. of the ring. It is necessary that the rings be cut to the
correct size, otherwise service life is reduced.
4. Install one ring at a time. Make sure it is clean and has
not picked up any dirt in handling. If clean oil is available,
lubricate the shaft and inside of the stuffing box. Seat
rings firmly. (Except for TFE filament and graphite 19 yarn
packings which should be snugged up very gently. Then
wrench in gradually.. .after the pump is back in opera-
tion.) Joints of successive rings should be staggered and
kept at least 90° apart. Each individual ring should be
firmly seated with a tamping tool. When enough rings
have been individually seated so the nose of the gland will
reach them, individual tamping should be supplemented
by the gland. Never depend entirely on the gland to seat a
set of rings properly-this practice will jam the last rings
installed, but leave the bottom rings loose in the box.
5. After the last ring is installed, take up bolts finger tight
or very slightly snugged up. Do not jam the packing into
place by excessive gland loading. Start pump, and take
up bolts until leakage is decreased to a minimum. Make
sure gland bolts are taken up evenly, stopping leakage
entirely at this point will cause 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. Final adjustment should allow approxi-
mately 30 drops per minute to leak from the packing.
7. When specified, Rotech can provide means of lubricat-
ing the shaft and packing through a lantern ring by
supplying water, oil, grease, or liquid handled in the
pump.
8. If the stuffing box has a lantern ring, make sure the
lantern ring, as installed, is slightly behind the fluid inlet
as gland pressure is applied. (Fig 10)
Fig. 10