| Live loading is designed to provide gland load retention for in-service consolidation
of the packing. A set of disc-spring washers placed on each gland stud bolt between the
gland flange and gland bolt nut helps to exert a continuous compressive force on the gland
follower flange and, therefore, on the packing set. The benefits of live loading are
found to be in applications where any one of five criteria is present:
- Valves where 5,000 or more complete stem actuations are anticipated prior to the next
scheduled re-packing or the valve stem is in a state of constant modulation
- Standard installation procedures can not be followed
- The valve in question has been determined to be "critical" to the operation
process
- Multiple thermal cycling of the valve is anticipated due to the process system in which
the valve is installed
- The valve's location makes it inaccessible for future adjustment
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