SUPERVISION AND MAINTENANCE
Stuffing Box:
The purpose of a stuffing box is to limit or eliminate leakage of the pump fluid and
to prevent air from
entering the suction spaces along the pump shaft. Pumps are
equipped with packing (limited leakage) or
mechanical seals (no leakage).
Normally, the pumped liquid is used to lubricate the stuffing box seal. If
the liquid
is dirty, gritty, or contains material that would gum or jam the seal, use a sealing
liquid from an
external source. If suction pressure is above atmospheric pressure,
seal piping may not be required. For
pumps equipped with packing, there must
always be leakage of 100 drops/minute aproxi, but we recommend a steady
dripping of liquid through the gland. Stuffing box
glands should be adjusted after
the pump is started. When leakage is excessive, tighten gland bolts evenly a little
at a time. Allow an interval for packing to adjust to new position. Never tighten
gland to be leak proof, as this will cause overheating and undue wear on shaft
sleeves. Replace stuffing box packing as follows:
1. Shutdown the pump.
2. Take precautions to prevent the driver from being inadvertently started.
3. Remove the gland bolt nuts and gland.
4. Remove and discard old packing rings
– note location of lantern ring. When
repacking stuffing box, lantern ring must be positioned such that the water seal
connection is opposite lantern ring.
5. Clean out the stuffing box.
6. Inspect shaft sleeve, if it is scored or grooved, it should be replaced.
7. Make sure the st. box bushing (if furnished) is set at the bottom of the box.
8. Insert rings of packing and tap lightly to seat against bushing. Be sure rings are
of the proper size an length and installed with cuts staggered. Lantern ring must
be installed opposite sealing water connection.
9. Install gland and finger tight. While the pump running, adjust gland. Care
should be taken during the first hour of operation to take up on the packing
gradually just enough to maintain the required amount of leakage. If the pump is
operated continuously the packing should be renewed about every two to three
months before it gets hard and scores the shaft sleeves. Mechanical seals should
be removed, assembled, and/or adjusted according to the seal manufacturer's
instructions. There should be no leakage from the gland if mechanical seals are
used, except for a brief run in period.
Bearings:
Frequency of lubrication depends upon operating conditions and environment,
therefore, lubrication intervals must be determined by experience. Lubricants
need replacing only because of
contamination by dirt or dust, metal particles, moisture or high temperature
breakdown.
A small amount of grease may be added about every 400 hours of operation. The
bearing housing should be about 1/3 full of grease. All lubricants have a