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Packing Procedures

The importance of correct installation of gland packing to achieve satisfactory performance cannot be overemphasized. The following steps outline these procedures:

  1. Shut the system down, isolating the equipment to be packed. Flush the system if required, and relieve internal equipment pressure. Disable the motor to prevent accidental start-up. Use all safety equipment required.
  2. Remove all of the old packing from the stuffing box. Note the proper location of the lantern ring (if one is used). Clean the stuffing box and shaft thoroughly. Examine the shaft or shaft sleeve for excessive wear and replace the shaft or sleeve if it is worn or scored. Test the bearings and replace them if end play or whip is outside the equipment manufacturer’s specifications or more than 0.01mm TIR. Check bearing oil for contamination and change it and the oil seals if needed. Examine the stuffing box carefully. Large corrosion pits of ‘blow holes” in the casting can provide leak paths along the outside of the packing set which can be impossible to seal without placing excessive gland pressure on the packing set. This can cause premature failure by eliminating the lubrication film under the packing. Fill these pits with compatible epoxy or weld. Packing rings must not be “hung up” by a stuffing box bore that is too rough.
  3. From bulk packing, cut rings on a mandrel of the same diameter as the shaft. Slide the rings off the mandrel. Keep the packing clean. Remember that dirt on new packing reduces service life.
  4. Install one ring at a time. Twist the ring sideways to open it enough to slip over the shaft. Push each ring into the stuffing box individually until it is seated. Stagger the ring joints keeping them at least 90 degrees apart. Install the lantern ring in the proper location within the packing set.
  5. After the last ring is installed. Draw the gland up evenly and tighten the gland bolts Finger Tight only! Turn the pump shaft by hand to ensure that there is no binding.
  6. Do Not Start Dry! Turn on the seal water, enable motor, open the valves and fold the pump cavity. Bleed air from the system.
  7. Start the pump, allowing generous leakage, and take up on the gland bolts gradually one flat at a time. Continue to take up on the gland bolts until leakage is reduce to an acceptable level. Do not try to stop all leakage! With the exception of a few styles in certain application, dry running can glaze the packing set and cause packing failure. Remember that pump packing should leak a little to work. Allowing a little more leakage at start-up often multiples the packing service life.