1. Steve Lefler - Principal Engineer Duke Energy
Catawba Nuclear Station Industry Perspective – HDPE Applications and Economic Benefits
Steve Lefler - Principal Engineer Duke Energy

2. Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Located 19 miles southwest of Charlotte, NC on shores of Lake Wylie
Two Units 1160 MW each (net) Westinghouse PWR
Main condenser cooling provided by forced draft cooling towers
Once through service water systems use Lake Wylie for cooling
Commercial operation in 1985 (Unit 1) and 1986 (Unit 2)
Catawba is jointly owned by:
North Carolina Electric Membership Corporation
North Carolina Municipal Power Agency Number One
Piedmont Municipal Power Agency
Duke Energy

3. Both systems combined total approximately 45,000-50,000 feet of piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Site Background
Low Pressure Service Water System secondary cooling and cooling tower makeup. (Designed to ASME B31.1 Code or Civil Building Codes)
Nuclear Service Water System cooling to nuclear safety related components that now includes 4000 feet of HDPE. (Designed to ASME Section III ND Code)
Both systems combined total approximately 45,000-50,000 feet of piping

4. Both systems combined total approximately 45,000-50,000 feet of piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Site Background
Low Pressure Service Water System secondary cooling and cooling tower makeup. (Designed to ASME B31.1 Code or Civil Building Codes)
Nuclear Service Water System cooling to nuclear safety related components. (Designed to ASME Section III ND Code)
Both systems combined total approximately 45,000-50,000 feet of piping

5. Operating Issues with original carbon steel piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Operating Issues with original carbon steel piping
Fouling and Occlusion
General Corrosion
Through wall pin hole leaks
Selective Weld Zone Attack

6. Fouling of carbon steel piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Fouling of carbon steel piping

7. Fouling of carbon steel piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Fouling of carbon steel piping

8. HDPE piping -generator hydrogen coolers
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
HDPE piping -generator hydrogen coolers

9. Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
comparison of carbon steel and HDPE generator hydrogen cooler pipe

10. Reliability improved with use of HDPE Before replacement with HDPE:
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Reliability improved with use of HDPE
Before replacement with HDPE:
Flow control valves fully open to the containment ventilation chillers
Chiller condenser pressures near 150 psig trip set point
After replacement with HDPE and two operating cycles:
Flow control valves 50% open
Chiller condenser pressure around 125 psig

11. Unit 1 realized a 20-25% flow margin improvement due to HDPE.
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
ASME Class 3 HDPE
Unit 1 realized a 20-25% flow margin improvement due to HDPE.
Unit 2 has data indicates that improvement will be on the order of 15%. The Unit 2 improvement is less than Unit 1 improvement because of the smaller amount of buried piping on Unit 2.

12. Selective weld attack of carbon steel piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Selective weld attack of carbon steel piping

13. Selective weld attack of carbon steel piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Selective weld attack of carbon steel piping

14. External corrosion of buried carbon steel piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
External corrosion of buried carbon steel piping

15. Installation of 32 inch HDPE piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Installation of 32 inch HDPE piping

16. Installation of 32 inch HDPE piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Installation of 32 inch HDPE piping

17. Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
HDPE Piping

18. Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
HDPE piping

19. Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Success with use of HDPE for non safety system service water system led to decision to pursue use of HDPE for safety related nuclear service water system
EDF Sizewell B Nuclear Station installed HDPE in ASME Section III Class 3 system and now has several miles of HDPE installed in nuclear safety related cooling water piping in the United Kingdom.

20. Summary of Catawba Relief Request
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Summary of Catawba Relief Request
Limited to replacement of buried ASME Section III Class 3 service water piping for the four emergency diesel generators for Units 1 and 2
HDPE design and installation requirements based on draft of Code Case N-755 Rev. 0
Limited to HDPE Pipe, Mitered Elbows and Flange Adapters
Limited to Butt fused joints and flanged joints

21. Timeline – Catawba HDPE Use
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Timeline – Catawba HDPE Use
1995 – HDPE used in non safety service water system
June 2005 – Meeting with NRC to discuss HDPE for ASME Class 3
October 2006 – Relief request submitted to the NRC
March 2007 – ASME Code Case N-755 issued
May 2009 – NRC issued Catawba safety evaluation
June 2009 – Began installation of ASME Class 3 HDPE piping
October 2010 – Unit 2 ASME Class 3 HDPE, buried service water piping to the emergency diesel generators completed and in service
June 2011 – Unit 1 ASME Class 3 HDPE, buried service water piping to the emergency diesel generators completed and in service

22. Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic
Summary of Catawba HDPE for nuclear safety related cooling water piping
4,000 feet of 12 inch HDPE pipe, SDR 11 (1.159 in. wall thickness)
HDPE 4710 Material (ASTM D3350 cell classification C)
Replaced 10 inch sch 40 carbon steel piping abandoned in place
Transitions from HDPE to steel were made in underground vaults
Impact tensile testing performed to demonstrate joint integrity

23. Safety Evaluation for Catawba
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Safety Evaluation for Catawba
Supplemental Requirements to Code Case N-755 imposed by the NRC safety evaluation issued for the Catawba relief request.
HDPE flaw depth allowance of inches
Reporting of ongoing industry HDPE test program results
Periodic tensile impact testing of field joints
Provision for access to inside of pipe
Remote visual inspection of fused joints from inside pipe

24. Installation of 12 inch ASME Cl. 3 HDPE piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Installation of 12 inch ASME Cl. 3 HDPE piping

25. Installation of 12 inch ASME Class 3 HDPE piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Installation of 12 inch ASME Class 3 HDPE piping

26. Access to inside of HDPE piping provided by tee with blind flange
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Access to inside of HDPE piping provided by tee with blind flange

27. Fusing 12 inch ASME Class 3 HDPE piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Fusing 12 inch ASME Class 3 HDPE piping

28. Fusing joint for ASME Class 3 HDPE
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Fusing joint for ASME Class 3 HDPE

29. Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits

30. Installation of 12 inch ASME Cl. 3 HDPE piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Installation of 12 inch ASME Cl. 3 HDPE piping

31. Evaluation for Gouge Depth in HDPE Piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Evaluation for Gouge Depth in HDPE Piping

32. Evaluation for Gouge Depth in HDPE Piping
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Evaluation for Gouge Depth in HDPE Piping
Typical scratches in HDPE
Sample
NPS DR
Depth % 1 24 9
0.022 in
0.8 2
0.140 in
6.3 3 8 17
0.029 in
5.5 4 11
3.7 5 30 21
0.049 in
2.7 6
0.032 in
2.3 7 12
0.039 in
3.3
0.071 in
6.1 10
0.047 in
4.9 20
0.002 in
0.001
Sample 5

33. Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Catawba NRC Safety Evaluation Requirements
Periodic Tensile Impact Testing
Impact tensile testing performed on daily and random samples of fused joints.
Impact tensile test first fusion joint of each work shift for each fusing machine (daily joint).
Impact tensile test one random fusion joint chosen during a four work shift period.
At least 10 percent of field joints from each machine required to be tested during a production shift.
Fused joints involving fittings were excluded from random testing.

34. ASTM F 2634, Standard Test Method for Testing PE Butt Fusion Joints
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
ASTM F 2634, Standard Test Method for Testing PE Butt Fusion Joints

35. Catawba NRC Safety Evaluation Requirements
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Catawba NRC Safety Evaluation Requirements
Periodic Tensile Impact Testing U N I T
Joints
Daily Joints
Random
Total
% of Joints
Tested 1
107 66 16
189
43% 2 63 40 8
111
1&2
170
106 24
300

36. Catawba NRC Safety Evaluation Requirements
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Catawba NRC Safety Evaluation Requirements
Periodic Tensile Impact Testing
No failures of tensile impact tests provided high level of confidence in installed fused joints
A minimum of 20% of the joints were tested each work shift compared to the minimum of 10% required by the safety evaluation
Random testing performed on 13% of the Unit 1 joints
Random testing performed on 11% of the Unit 2 joints

37. Estimated Project Cost August 2006
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Estimated Project Cost
August 2006
Item
6% Moly
HDPE
Total Project
$ (millions)
32.6
20.9
Material Cost
13.8
2.9
Labor Cost
18.5
17.6

38. Relative Material Costs
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Relative Material Costs

39. Comparison of 6% Moly and HDPE Materials
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Comparison of 6% Moly and HDPE Materials
Item
6 % Moly
HDPE
Carbon Stl
Pipe
$750
$61.70
$33.30
90o Elbow
$8070
$600
$558.31
Tee
$8507 NA -
Flange
$4336
Joints
10 hours
30 minutes

40. Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Much of the potential cost savings was not realized.
Project costs that were not accurately estimated or considered:
Cost for testing of HDPE joints
Qualification of fusing process
Excavation
Backfilling
Transition vaults for flanged joints
Costs associated with schedule delays and changes

41. Regulator approval of ASME Code Case for use of HDPE
Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Target Areas to Support Future HDPE for nuclear safety related cooling water service
Regulator approval of ASME Code Case for use of HDPE
Non Destructive Testing for Joints and Acceptance Standard
Resistance to slow crack growth at higher temperatures
Fusion joint process qualification
Complete development of code requirements for above ground use of HDPE and regulator approval.
Develop approval for use of electrofusion joints
Approval of additional fittings (tees, reducers, branch fittings)

42. Catawba Nuclear Station Industry Perspective on HDPE Applications and Economic Benefits
Summary
HDPE used in service water piping at Catawba has proven to be effective and cost efficient for solving fouling and corrosion problems.
Questions?