Page 240 - Root Cause Failure Analysis

228 Root Cause Failure Analysis

Figure 18-10 Proper lantern ring installation (Bearings Inc. catalogue).

23. Tighten up the gland bolts with a wrench to seat and form the packing to
the stuffing box and shaft.
24. Loosen the gland nuts one complete turn and rotate the shaft by hand to get
running clearance.
25. Retighten the nuts finger tight only. Again, rotate the shaft by hand to make
sure the packing is not too tight.
26. Have the operator start the pump and allow the stuffing box to leak freely.
Tighten the gland bolts one flat at a time until the desired leakage is
obtained and the pump runs cool.
27. Clean up the work area and account for all tools before returning them to
the tool crib.
28. Inform operations of project status and complete all paperwork.
29. After the pump is in operation, periodically inspect the gland to check its
performance. If it tends to leak more than the allowable amount, tighten by
turning the nuts one flat at a time. Give the packing enough time to adjust
before tightening it more, If the gland is tightened too much at one time,
the packing can be compressed excessively, which can cause unnecessary
friction and subsequent packing burnout.

Mechanical Seals
Much more precision and attention to detail must be given to the installation of
mechanical seals than to packing. Nevertheless, it is not unusual for mechanical seals
to remain in service for many thousands of operational hours if they have been prop-