ML022520415
| ML022520415 | |
| Person / Time | |
|---|---|
| Issue date: | 09/09/2002 |
| From: | Lund A NRC/NRR/DE/EMCB |
| To: | Jeffrey Riley Nuclear Energy Institute |
| Murphy E | |
| Shared Package | |
| ML022520413 | List: |
| References | |
| Download: ML022520415 (6) | |
Text
ENCLOSURE 1 Sample Administrative Technical Specifications
- Steam Generators with Alloy 600 MA Tubing 5.5.9 Steam Generator Program a.
A Steam Generator Program shall be established and implemented to ensure that steam generator tube integrity is maintained. Steam generator tube integrity is maintained by meeting the following tube integrity performance criteria:
1.
Structural Integrity Performance Criteria: Steam generator tubing shall retain structural integrity over the full range of normal operating conditions (including startup, operation in the power range, hot standby and cooldown and all anticipated transients included in the design specification). This includes retaining a margin of 3.0 against burst under normal steady state full power operation and a margin of 1.4 against burst under the limiting design basis accident or combination of accidents as is required by the existing design and licensing basis. Note: revised words pertaining to the 1.4 factor may be necessary.
Burst is defined as gross structural failure of the tube wall. The condition typically corresponds to an unstable opening displacement (e.g., opening area increased in response to constant pressure) accompanied by ductile (plastic) tearing of the tube material at the ends of the degradation.
2.
Accident Leakage Integrity Performance Criteria: The primary-to-secondary accident induced leakage rate for the limiting design basis accident, other than a steam generator tube rupture, shall not exceed [the leakage rate assumed in the accident analyses in terms of total leakage rate for all steam generators and leakage rate for an individual steam generator]. Leakage is not to exceed [1 gpm per steam generator].
3.
Operational Leakage Integrity Performance Criteria: The RCS operational primary-to-secondary leakage rate through any one steam generator shall not exceed 150 gallons per day (gpd).
b.
Condition monitoring assessments shall be conducted during each outage during which the steam generators tubes are inspected, plugged, or repaired to confirm that the structural integrity and accident leakage performance criteria are being met.
Condition monitoring assessment means an evaluation of the as found condition of the tubing with respect to the structural integrity and accident leakage performance criteria. The as found condition refers to the condition of the tubing during a steam generator tube inspection outage, as determined from inservice inspection results or by other means, prior to the plugging or repair of tubes.
c.
Steam Generator Inspection Intervals: Steam generator tube inspection intervals shall be established and implemented to ensure that the steam generator tube integrity is maintained. In addition, the inspection interval for each steam generator shall not exceed one fuel cycle or 24 EFPM, whichever is less.
d.
Tube Repair Criteria (i.e., tube plugging limits): Tubes found by inservice inspection to contain flaws with a depth equal to or exceeding [40%] of the nominal tube wall thickness shall be plugged [or repaired] prior to plant restart (entry into Mode 4). [The following tube repair criteria may be applied as an alternative to the 40% depth-based limit:
Alternate tube repair criteria currently permitted by plant technical specifications are to be listed here. The description of these alternate tube repair criteria should be equivalent to the descriptions in current technical specifications.]
Tube repair criteria mean the acceptance criteria in terms of allowable flaw [depth] to be applied to the results of inservice inspection of the tubing.
[e.
Tube repair methods: Tubes found by inservice inspection to contain flaws not meeting the tube repair criteria may be repaired prior to plant restart in lieu of being plugged.
Repair methods shall be as follows:
Tube repair methods currently permitted by plant technical specifications are to be listed here. The description of these tube repair methods should be equivalent to the descriptions in current technical specifications.]
Tube repair methods refer to methods for restoring the integrity of flawed sections of tubing such that the tube is acceptable for continued service without plugging. Plugging of tubes does not constitute a tube repair method.]
Sample Administrative Technical Specifications
- Steam Generators with Alloy 600 TT Tubing 5.5.9 Steam Generator Program a.
A Steam Generator Program shall be established and implemented to ensure that steam generator tube integrity is maintained. Steam generator tube integrity is maintained by meeting the following tube integrity performance criteria:
1.
Structural Integrity Performance Criteria: Steam generator tubing shall retain structural integrity over the full range of normal operating conditions (including startup, operation in the power range, hot standby and cooldown and all anticipated transients included in the design specification). This includes retaining a margin of 3.0 against burst under normal steady state full power operation and a margin of 1.4 against burst under the limiting design basis accident or combination of accidents as is required by the existing design and licensing basis. Note: revised words pertaining to the 1.4 factor may be necessary.
Burst is defined as gross structural failure of the tube wall. The condition typically corresponds to an unstable opening displacement (e.g., opening area increased in response to constant pressure) accompanied by ductile (plastic) tearing of the tube material at the ends of the degradation.
2.
Accident Leakage Integrity Performance Criteria: The primary-to-secondary accident induced leakage rate for the limiting design basis accident, other than a steam generator tube rupture, shall not exceed [the leakage rate assumed in the accident analyses in terms of total leakage rate for all steam generators and leakage rate for an individual steam generator]. Leakage is not to exceed [1 gpm per steam generator].
3.
Operational Leakage Integrity Performance Criteria: The RCS operational primary-to-secondary leakage rate through any one steam generator shall not exceed 150 gallons per day (gpd).
b.
Condition monitoring assessments shall be conducted during each outage during which the steam generators tubes are inspected, plugged, or repaired to confirm that the structural integrity and accident leakage performance criteria are being met.
Condition monitoring assessment means an evaluation of the as found condition of the tubing with respect to the structural integrity and accident leakage performance criteria. The as found condition refers to the condition of the tubing during a steam generator tube inspection outage, as determined from inservice inspection results or by other means, prior to the plugging or repair of tubes.
c.
Steam Generator Inspection Intervals: Steam generator tube inspection intervals shall be established and implemented to ensure that the steam generator tube integrity is maintained. In addition, the inspection interval for each steam generator shall be limited as follows:
1.
Except as provided for in 2., inspect 100% of tubes at sequential intervals of 120, 90, and, thereafter, 60 EFPM. The first sequential interval shall be considered to begin at the first inservice inspection of the steam generators. In addition, inspect 50% of the tubes by the refueling outage nearest the mid point of the interval and the remaining 50% by the refueling outage near the end of the interval. No steam generator can operate for more than two fuel cycles or 48 EFPM, whichever is less, without being inspected.
2.
If any steam generator contains a degradation mechanism(s) exceeding the degradation activity threshold during a given inspection, the next inspection interval for each steam generator for the subject degradation mechanism(s) shall not exceed one fuel cycle or 24 EFPM, whichever is less.
Degradation activity threshold refers to any of the following:
1.
A combination of ten or more new indications (> 20% of the initial tube wall thickness) of thinning, pitting, wear, impingement, or other form of volumetric indications which display an average growth rate equal to or greater than 25% of the tube repair limit in one inspection-to-inspection interval. Damage from loose parts or foreign objects may be excluded from consideration only if the causal objects are identified and removed from the steam generators.
2.
One or more new or previously identified indications (> 20% of the initial tube wall thickness) which display a growth increment greater than or equal to the tube repair criteria in one inspection-to-inspection interval. Damage from loose parts or foreign objects may be excluded from consideration only if the causal objects are identified and removed from the steam generators.
3.
Any crack indication (e.g., outside diameter intergranular attack/stress corrosion cracking or inside diameter stress corrosion cracking).
d.
Tube Repair Criteria (i.e., tube plugging limits): Tubes found by inservice inspection to contain flaws with a depth equal to or exceeding [40%] of the nominal tube wall thickness shall be plugged prior to plant restart (entry into Mode 4).
Tube repair criteria mean the acceptance criteria in terms of allowable flaw depth to be applied to the results of inservice inspection of the tubing.
Sample Administrative Technical Specifications
- Steam Generators with Alloy 690 TT Tubing 5.5.9 Steam Generator Program a.
A Steam Generator Program shall be established and implemented to ensure that steam generator tube integrity is maintained. Steam generator tube integrity is maintained by meeting the following tube integrity performance criteria:
1.
Structural Integrity Performance Criteria: Steam generator tubing shall retain structural integrity over the full range of normal operating conditions (including startup, operation in the power range, hot standby and cooldown and all anticipated transients included in the design specification). This includes retaining a margin of 3.0 against burst under normal steady state full power operation and a margin of 1.4 against burst under the limiting design basis accident or combination of accidents as is required by the existing design and licensing basis. Note: revised words pertaining to the 1.4 factor may be necessary.
Burst is defined as gross structural failure of the tube wall. The condition typically corresponds to an unstable opening displacement (e.g., opening area increased in response to constant pressure) accompanied by ductile (plastic) tearing of the tube material at the ends of the degradation.
2.
Accident Leakage Integrity Performance Criteria: The primary-to-secondary accident induced leakage rate for the limiting design basis accident, other than a steam generator tube rupture, shall not exceed [the leakage rate assumed in the accident analyses in terms of total leakage rate for all steam generators and leakage rate for an individual steam generator]. Leakage is not to exceed [1 gpm per steam generator].
3.
Operational Leakage Integrity Performance Criteria: The RCS operational primary-to-secondary leakage rate through any one steam generator shall not exceed 150 gallons per day (gpd).
b.
Condition monitoring assessments shall be conducted during each outage during which the steam generators tubes are inspected, plugged, or repaired to confirm that the structural integrity and accident leakage performance criteria are being met.
Condition monitoring assessment means an evaluation of the as found condition of the tubing with respect to the structural integrity and accident leakage performance criteria. The as found condition refers to the condition of the tubing during a steam generator tube inspection outage, as determined from inservice inspection results or by other means, prior to the plugging or repair of tubes.
c.
Steam Generator Inspection Intervals: Steam generator tube inspection intervals shall be established and implemented to ensure that the steam generator tube integrity is maintained. In addition, the inspection interval for each steam generator shall be limited as follows:
1.
Except as provided in 2., inspect 100% of tubes at sequential intervals of 144, 108, 72, and, thereafter, 60 EFPM. The first sequential interval shall be considered to begin at the first inservice inspection of the steam generators. In addition, inspect 50% of the tubes by the refueling outage nearest the mid point of the interval and the remaining 50% by the refueling outage near the end of the interval. No steam generator can operate for more than three fuel cycles or 72 EFPM, whichever is less, without being inspected.
2.
If any steam generator contains a degradation mechanism(s) exceeding the degradation activity threshold during a given inspection, the inspection interval for each steam generator for the subject degradation mechanism(s) shall not exceed one fuel cycle or 24 EFPM.
Degradation activity threshold refers to any of the following:
1.
A combination of ten or more new indications (> 20% of the initial tube wall thickness) of thinning, pitting, wear, impingement, or other form of volumetric indications which display an average growth rate equal to or greater than 25% of the tube repair limit in one inspection-to-inspection interval. Damage from loose parts or foreign objects may be excluded from consideration only if the causal objects are identified and removed from the steam generators.
2.
One or more new or previously identified indications (> 20% of the initial tube wall thickness) which display a growth increment greater than or equal to the tube repair criteria in one inspection-to-inspection interval. Damage from loose parts or foreign objects may be excluded from consideration only if the causal objects are identified and removed from the steam generators.
3.
Any crack indication (e.g., outside diameter intergranular attack/stress corrosion cracking or inside diameter stress corrosion cracking).
4.
Tube Repair Criteria (i.e., tube plugging limits): Tubes found by inservice inspection to contain flaws with a depth equal to or exceeding [40%] of the nominal tube wall thickness shall be plugged prior to plant restart (entry into Mode 4).
Tube repair criteria mean the acceptance criteria in terms of allowable flaw depth to be applied to the results of inservice inspection of the tubing.