Nuclear Power Plant: Steam Turbine Inner Casing Closure

• Turnaround Time Shortened By ONE Month!!!
• Water Charged Hydraulic Nuts.
• Greater Loads Produced Within A Restricted Footprint.

Problem:

1. Insufficient loading using conventional torquing methods led to steam leaks due to warped (“smile”) flanges.
2. Labor intensive operations led to over budgeted turnarounds.
3. Steam path cannot be subjected to contaminants.

Solution:

1. Simultaneous tensioning of studs provided precise loading allowing full flange closure .
2. Labor hours drastically reduced. Turnaround shortened by one month.
3. Water charged hydraulic nuts eliminated contamination concerns.