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Insert packing rings making sure the joints are staggered 180 degrees and that each ring is
tamped firmly in place. When the packing box is sufficiently full to allow entry of the gland about
¼ inch, reassemble the packing gland, clip and nuts. Draw up evenly on the gland to assure
proper seating of the packing. The gland nuts should then be backed off until finger-tight. After
the pump is started, visually examine the stuffing box for excessive leakage. If the packing
leakage exceeds ten drops per minute, stop the pump and adjust the gland nuts. The gland nuts
should be adjusted evenly in 1/6 to 1/3 turn (1 to 2 flats on the nut) increments. Start the pump
and allow it to operate for several minutes. Again, visually examine the stuffing box for excessive
leakage. Repeat the above procedure until the stuffing box leakage is between five to ten drops
per minute.
DO NOT overtighten the packing. Slight leakage is a necessary requirement for proper packing
operation. Leakage of five to ten drops per minute when the pump is operating is desirable, as it
will preserve the packing and avoid scoring of the shaft. Overtight packing may score shafts,
increase torque requirements of the pump, damage couplings and drives, and generate excessive
heat.
The packing gland should be adjusted whenever leakage exceeds ten drops per minute. The
condition of the packing should be checked at regular intervals, the frequency depending on the
type of service. Experience will dictate how frequently the inspections should be made.
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