United States Nuclear Regulatory Commission - Protecting People and the Environment

Information Notice No. 89-28: Weight and Center of Gravity Discrepancies for Copes-Vulcan Air-Operated Valves

                                  UNITED STATES
                          NUCLEAR REGULATORY COMMISSION
                      OFFICE OF NUCLEAR REACTOR REGULATION
                             WASHINGTON, D.C.  20555

                                 March 14, 1989


Information Notice No. 89-28:  WEIGHT AND center OF GRAVITY DISCREPANCIES
                                   FOR COPES-VULCAN AIR-OPERATED VALVES


Addressees:

All holders of operating licenses or construction permits for nuclear power 
reactors.

Purpose:

This information notice is being provided to alert addressees to potential 
problems resulting from incorrect weight and center of gravity information 
provided by Copes-Vulcan, Incorporated (CV) with air-operated valves which 
they supplied before 1980.  It is expected that recipients will review the 
information for applicability to their facilities and consider actions, as 
appropriate, to evaluate the significance of any discovered discrepancies.  
However, the suggestions contained in this information notice do not consti-
tute NRC requirements; therefore, no specific action or written response is 
required.

Description of Circumstances:

During recent reverification of piping stress analyses at the Prairie Island 
Nuclear Station, significant discrepancies were discovered in valve weight 
and center of gravity information for air-operated valves supplied by CV.  
Copes-Vulcan, (formerly the Blaw Knox Company), is a division of White 
Consolidated Industries.  Before 1980, the information listed on the valve 
drawings in many cases did not account for the air operator and, consequently, 
significant-ly understated the valve assembly weight and center of gravity.  
Some of these valves are located in various lines connected to the accumulator 
tanks of the safety injection system, and in the charging and letdown systems.  
The new piping stress analyses performed for Prairie Island with the corrected 
values have shown that, as a result of this discrepancy, the allowable code 
stresses have been exceeded in many cases.  In several instances, the piping 
stress analyses brought into question the ability of the associated system to 
withstand a seismic event.  

The NRC has also confirmed the existence of this discrepancy at the D. C. Cook 
and Zion stations at which a number of the same valves were identified in 
safety systems.  Reanalyses at the D. C. Cook station using the appropriate 
values for valve weight and center of gravity resulted in piping stresses that 
exceeded the allowable code limits.  In at least one instance, the stresses 
exceeded the allowable limits to the extent that the operability of the 
associated piping 


8903080372
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system was brought into question.  At Zion, the extended valve operators were 
supported independently minimizing the impact of the discrepancies in the 
weight or center of gravity location on the stress analyses.

Discussion:

As far as the NRC is aware, the incorrect information supplied by CV has only
affected small-bore piping systems having valves ranging in size from 3/4 inch 
to 3 inches with pressure ratings ranging from 150 psi to 1500 psi. Table 1 is 
a partial listing of the valves supplied with the incorrect information.  NRC 
does not know if any larger valves are affected.  The actual valve weights are 
as much as 40 percent greater than the values originally provided, although in 
a few cases the actual weights are less.  All of the center of gravity values 
are significantly different from the original values provided.  The original 
center of gravity locations were given as approximately 5 inches from the 
datum points, while the actual locations range from 15 to 20 inches from the 
datum points.  The corrections of the center of gravity values typically have 
resulted in the most significant problems in meeting allowable code stress 
levels.

IE Bulletin 79-14, "Seismic Analyses for As-Built Safety-Related Piping 
Systems," which was issued July 2, 1979, required all power reactor owners to 
verify that their seismic analyses applied to the actual configuration of 
safety-related piping.  That bulletin applied only to safety-related piping 2 
1/2 inches in diameter and greater and to seismic Category I piping, 
regardless of size, that was dynamically analyzed by computer.  The incorrect 
information supplied with the CV valves mainly affected small-bore piping 
systems and is generally outside of the scope of Bulletin 79-14.  However, 
since the small-bore piping had been analyzed by computer, the licensee for 
Prairie Island included this piping in its verification program required by 
Bulletin 79-14.  It was during a reverifi-cation of the Bulletin 79-14 program 
that the recent CV valve data was found to differ from the original data.

The discovery of the incorrect CV valve data at D. C. Cook and Zion was made 
as a result of NRC inquiries following the Prairie Island discovery.  The 
original design criteria for small-bore piping at these plants was based on 
generic span and standardized support criteria and was not part of the 
Bulletin 79-14 scope.  At Zion, the extended valve operators are independently 
supported, therefore, the incorrect valve information did not cause any 
significant problems.  However, CV typically recommended that attachments be 
made no higher than the body-to-bonnet flange connection.  If the valves are 
supported in a manner not recommended by the manufacturer, it is important 
that the utility ensure that the valves are requalified with appropriately 
induced loads from the piping system.  Analyses of the valve assemblies at 
Zion showed that the valves are qualified with the installed support systems, 
even though they do not comply with the vendor recommendations for supports.

Additional information on this problem was obtained during an NRC inspection 
at CV.  The incorrect valve weight and center of gravity information typically 
was supplied to the licensees' Nuclear Steam System Suppliers or 
Architect-Engineers before 1980, who supplied it along with the system designs 
to the licensees.  In 1988, CV notified its purchasers of the incorrect valve 
weights and center of 

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                                                            March 14, 1989
                                                            Page 3 of 3


gravity values.  A copy of the CV letter to the purchasers is attached.  
However, as these pur-chasers were usually Nuclear Steam System Suppliers and 
Architect-Engineers, some licensees who were the final users may not have been 
notified of the problem in a timely fashion.  Additional technical information 
and a partial list of licensees who may have received the incorrect 
information can be found in the NRC inspection report (99900080/88-01).  

No specific action or written response is required by this information notice.  
If you have any questions about this matter, please contact one of the techni-
cal contacts listed below or the Regional Administrator of the appropriate 
regional office.




                                   Charles E. Rossi, Director
                                   Division of Operational Events Assessment
                                   Office of Nuclear Reactor Regulation


Technical Contacts:  J. A. Gavula, RIII
                     (312) 790-5761

                     J. J. Petrosino, NRR
                     (301) 492-0979


Attachments:
1.  Table 1
2.  Copes-Vulcan Letter 
3.  List of Recently Issued NRC Information Notices 
..                                                            Attachment 3 
                                                            IN 89-28
                                                            March 14, 1989
                                                            Page 1 of 1

                             LIST OF RECENTLY ISSUED
                             NRC INFORMATION NOTICES
_____________________________________________________________________________
Information                                  Date of 
Notice No._____Subject_______________________Issuance_______Issued to________

89-27          Limitations on the Use        3/8/89         All holders of OLs
               of Waste Forms and High                      or CPs for nuclear
               Integrity Containers for                     power reactors, fuel
               the Disposal of Low-Level                    cycle licenses and
               Radioactive Waste                            certain by-product
                                                            materials licenses.

89-26          Instrument Air Supply to      3/7/89         All holders of OLs
               Safety-Related Equipment                     or CPs for nuclear
                                                            power reactors.

89-25          Unauthorized Transfer of      3/7/89         All U.S. NRC source,
               Ownership or Control of                      byproduct, and 
               Licensed Activities                          special nuclear 
                                                            material 
                                                            licensees.

89-24          Nuclear Criticality Safety    3/6/89         All fuel cycle
                                                            licensees and other
                                                            licensees 
                                                            possessing more 
                                                            than critical 
                                                            mass quantities of
                                                            special nuclear 
                                                            material.

89-23          Environmental Qualification   3/3/89         All holders of OLs
               of Litton-Veam CIR Series                    or CPs for nuclear
               Electrical Connectors                        power reactors.

89-22          Questionable Certification    3/3/89         All holders of OLs
               of Fasteners                                 or CPs for nuclear
                                                            power reactors.

89-21          Changes in Performance        2/27/89        All holders of OLs
               Characteristics of Molded-                   or CPs for nuclear
               Case Circuit Breakers                        power reactors.

88-73,         Direction-Dependent Leak      2/27/89        All holders of OLs
Supplement 1   Characteristics of Contain-                  or CPs for nuclear
               ment Purge Valves                            power reactors.

__________________________________________________________________________________
OL = Operating License
CP = Construction Permit 
..
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