ML20199K735

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Responds to 981123 Request by Providing Copy of Latest Draft of Info Notice Being Prepared Which Discusses Failure of Several Preaction Sprinker Sys Deluge Valves.Requests Submittal of Comments by 981120
ML20199K735
Person / Time
Site: Farley  Southern Nuclear icon.png
Issue date: 01/21/1999
From: Dennig R
NRC (Affiliation Not Assigned)
To: Pounder D
GRINNELL CORP. (FORMERLY ITT GRINNELL CORP.)
References
NUDOCS 9901270005
Download: ML20199K735 (6)
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Text

{{#Wiki_filter:- - - ..- . . January 21, 1999 Mr. Donild B. Pounder DISTRIBUTION G. Holthin M. Sallay Engineering S:ction Min!gsr - Central Files- ' L. Mirsh T. Johnson, Rll Research and Development PUBLIC . R. Dennig P. Skinner, Ril Grinnell Corporation PECB R/F S. West R. Caldwell, Ril 1467 Elmwood Avenue D. Matthews W. Bur +on H. Berkow Cranston, Rhode island 02910 J. Stolz J. Zimmerman OGC ACRS

SUBJECT:

REVIEW OF DRAFT INFORMATION NOTICE REGARDING INSERVICE TESTING OF THE A-4 MULTIMATIC DELUGE VALVE

Dear Mr. Pounder:

Per the request in your letter dated November 23,1998, we are providing you with a copy of the 

                . latest draft of an information notice (IN) we are preparing which discusses the failure of several preaction sprinkler system deluge valves at the Farley Nuclear Plant. This draft reflects comments provided by Mr. David Morey of Southem Nuclear Operating Company provided to Mr. Herbert Berkow by letter dated November 20,1998.

Please review the enclosed draft IN to ensure that the technical information regarding the event is accurate. Your cooperation in this matter is appreciated. Please return any commenti, you may have by close of business on February 12,1999. A copy of this request and your response will be placed in the Public Document Room for review by the public. Your response should be mailed to: U.S. Nuclear Regulatory Commission ' ATTN: William Burton Mail Stop: 0-12D1 -  !( Washington, D.C. 20555-0001 Please address any questions you may have on this matter to William Burton of my staff. . 1 Mr. Burton can be reached at 301-415-2853. If no comments are received by the close of ' 

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business on 1999 February 12,1999, we will assume the technical information in the notice is I correct. Sincerely, , Original signed by Thomas Koshy FOR Robert L. Dennig, Section Chief , Events Assessment And Genenc j 9901270005 990121 - , Communications Branch l PDR ADOCK'05000348 , Division of Reactor Program Management , P PDR - Office of Nuclear Reactor Regulation

Enclosure:

Draft Information Notice DOCUMENT NAME: G:\WFB\ GRIN _.LTR.WPD To roceive a copy of this document. indicate in the box C= Copy w/o attachment / enclosure E= Copy with attachment / enclosure N = No copy OFFICE PECB:DRPM SPLB . yJ SPLB PECB CPECB:D NAME W. Burton ihl M. Salley, h L. Marshh R. Denni & JSt  ! DATE lM/99 l1899 W !- I N99 / W99 //[99 \ ' OPflCIAL RECORD COPY l 

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         .                                                                                                                                           I UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF NUCLEAR REACTOR REGULATION WASHINGTON, D.C. 20555-0001 February xx,1999 NRC INFORMATION NOTICE 99-XX: FAILED FIRE PROTECTION DELUGE' VALVES AND POTENTIAL TESTING DEFICIENCIES IN PREACTION SPRINKLER SYSTEMS
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Addressees 

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All NRC licensees. Purpose g The U.S. Nuclear Regulatory Commission (NRC)isissuing this information notice to alert addressees to test methodologies for fire protodion deluge valves that may not adequately demonstrate valve operability. It is expected that recipients will review the information for applicability to their facilities and consideractions, as appropnate, to avoid similar problems. However, suggestions contained in thisinformation notice are not NRC requirements; therefore, no specific action or written response is required. } 

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Valves for sprinkler system automatic cordrol (SSAC) are used in fire protection systems that protect areas housing safety-related equipment and that also protect non-safety-related equipment used for safeWwidown. Many of these systems are used to provide primary fire I protectioriwid to meet the' s of 10 CFR Part 50, Appendix R, Section Ill.G. Poor l design, deficient maintenance inadequate testing of SSAC valves and associated selenoid valves can lead 20 a common-mode failure of the valves to perform their design function of providing adequate and reliable fire protection. This, in tum, can result in the failure of safety-related a fire coeurs. equipment arid (Aho inability to achieve and maintain a safe reac i l f L' The Model A 4 Multimap Valve manufactured by Grinnell is a deluge valve designed for use in fpe protection systemp. ~1t is used as a system control valve in deluge, preaction, and special of fire protepct' systems and may also provide for actuation of fire alarms when the operate, 

                          .        .rs valves contain connections for monitoring pressure in the diaphragm chamber and in the main water supply, for providing valve drainage and for supplying water to the diaphragm chamber. All required components for these connections are typically supplied by the valve                                           ,

manufacturer as " trim packages" and are included as part of the Underwriters Laboratories (UL) I' and Factory Mutual, Inc. (FM) certifications of the valves. Enclosure  : l I

IN 99-xx 

   .                                                                                   February xx,1999
 .                                                                                     Page 2 of 5 Description of Circumstances in ine week of March 4,1996, during surveillance testing of preaction sprinkler systems in the Farley Unit 1 fire protection system,5 of 11 SSAC valves (Grinnell Model A4 deluge valves) failed to trip open when water pressure was vented out of the diaphragm chamber. Upon additional testing, the licensee found that several other SSAC valves failed. The root-cause team, formed after the initial valve failures, concluded that the diaphragm was1 sticking to its retainer and push rod disk, that the push rod assembly showed weer4dts and eroded plating),

and that the associated solenoid valves were not properlydWeeding heter pressure out of the diaphragm area. / fa, The investigators found that the licensee was using a brasivedea ing p clean the chrome-plated push rod and the push rod guide in the naphragm retainers. The team theorized that this activity may have created rust particy that caused the sticking. In like manner, abrasives used to clean the solenoid valves coum cause the plunger assembly to stick. Grinnell does not recommend using any abrasives that fem metal because the solvents attack the valve seats and the main orifice. Grinnell r'ecomme cleaning the push rods, guides, and solenoid valves with only soap, watef,and clean clot . 

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The root-cause team also found that the solenoid valves were designed for operating pressures of approximately 150 psig (UL maximum rated pressurgis 175 psig), whereas the actual operating pressures often exceeded 150 psig (pressuresymetimes went as high as 225 psig). The staff theorizes that the valves may not be able to open against this pressure. 

                                                /         l           l Although the team did not conclusively deterinine the root cause of the valve failures, it recommended (1) replacing the diaphragms and solenoid valves, (2) installing new solenoid valves with a design pressure di 200 psi (and factory tested to 300 psi), (3) flushing the solenoid valve piping and diaphragm chamber when cleaning the solenoids, (4) requiring the use of only soap, water,'imd a clean cloth when cleaning the solenoid valves, (5) cleaning the solenoid and SSAC valves rngre fmquently, and (6) testing the valves more often - every 12 months in' stead of 18 montfisim the short term, the licensee increased testing to every 2,6, and 12 months After resetting theylves to improve reliability).

f s in subsequent walkdowns the team found that the piping for the deluge valve control drain lines had a 3/8-inch diametehn, stead of the %-inch diameter line usually supplied as part of the trim package provided by thd manufacturer and listed by the independent testing laboratory (i.e., UL orfM). The use of thehmaller drain line could potentially inhibit the bleedoff of water from the phragm chamber, ulting in increased pressure in the chamber. The staff notes that this ction, in tum, ld prevent the clapper from opening. 

          ^
                  . ' 'ry 1998, the licensee performed a scheduled surveillance test on several deluge v        in the preaction sprinkler system. One valve failed to trip, and the push rod had to be force'd back manually after completely iso!ating and draining the diaphragm chamber, closing the main isolation valve, opening the main drain, and opening the valve faceplate. Inspection of the rubber diaphragm showed a
  • dimple
  • near the diaphragm chamber supply inlet. The valve
had been left in the tripped condition for about 22 days in May 1997, then it was reset and left in l this position until this surveillance (for about 9 months). As a result of this failure, the licensee tes'ed a sample of six additional valves that had been left in a tripped condition for long periods.

i l l 

 .                                                                                                                         IN 99-xx
  • Februtry xx,1999 Page 3 of 5 One of these valves failed to trip electrically, inspection of this valve indicated that the push rod appeared to be misaligned in the retainer ring slot and iome corrosion had formed where the rod slides through the ring. Also, the diaphragm was stuck to the face of the push rod. In total, five of the six sample valves and one other valve failed to trip properly.
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In June 1998, as part of the ongoing testing program, one of the delugg valves)das manually actuated from its pull station; it failed to operate. An investigation ind d that the pull station housing had rotated and was preventing complete travel (i , fully )of the valve handle. After adjusting the pull station housing, the handle was ag the deluge valve successfully tripped. v The team commissioned by the licensee to study the . lems M the A-4 concluded that, although the cause and effect are not known, it ap that the failure ocogred within a tripped open valve exposed to pressure over time. Thisexposure s caused the valve to fail when reset. The team noted that the manufacturer does not rpoommend leaving the tripped-open valves pressurized for a significant length of time. 

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The staff is continuing to monitor the licensee's investigation into%e valve failures. Discussion 7 \ 

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The staff noted several potential problems as a result o event. First, as discussed above, when deluge valves were left in thejripped condition for i periods, the potential arose for the rubber diaphragm to bond to the pdsh rod and the flange When the valves are reset, the diaphragm could remain partially bonded to the flange,destricting flow from the diaphragm  ; chamber, and keeping the valve from operating. Bonding may be particularly pronounced in i systems using well waterpraw river water. It is a common practice for many plants to keep their preaction sprinkler deluge valves in a tripped condition for long periods, usually during owpges when we or other activities are taking place, which increases the likelihood l ' of spurioutgystem actuation.gGrinnell recommends that the valve be reset within 24 hours of any valve opershon and that tht(niemal components of valves be cleaned and incpected after l any valve operation. N a Second, the use of plant supplied or plant-designed trim packages instead of the UL- or FM-certified packages and ' ns supplied by the valve manufacturer may result in issues such as undersized drain lines, ich may restrict the bleedoff from the diaphragm chamber and further i valve actuation. . 

                          , an evaluatio        'Grinnell concluded that the valve release mechanism may be jamming the highp           re and surging conditions in the deluge system. The jamming may be toGaspindentations on the valve latch. Cleaning and inspection of the valves'intemal

! should reveal these potential problems. l While reviewing this event, the staff hoted that the licensee performs full-flow testing. It is the steff's understanding that many plants isolate the deluge valves from the main water supply

during valve testing. This practice is a potential testing weakness and may mask the actuation i

problems discussed herein. With the deluge valve isolated, a limited volume of water is trapped l In both the main line and the diaphragm chamber supply line. The water in the diaphragm i I l l l

IN 99-xx { i Fcbruary xx,1999 l ' Page 4 of 5 

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l chamber is slowly bled off until the clapper opens. If the diaphragm has conded to the flange, the inlet to the diaphragm chamber could be partially blocked, inhibiting (but not preventing) l valve actuation. However, during normal operation with full flow from the diaphragm chamber supply line, the prirnary flow path would follcw the supply line to the drain, thus trapping water in the diaphragm chamber and preventing valve actuation. Note the following statement in National Fire Protection Association Standard 25 (* Standard for the inspection, Testing, and Maintenance of Water-Based Fire Protection Systems,' 1995 edition, Jlection 6-4.3.2.2): *Each deluge or preaction valve shall be trip tested annually at fullflow [erJiphasis added] in warm l weather and in accordance with the manufacturer's instrusons." Th'e valve manufacturer may also have special requirements for inservice testing. Th6 A-4 valve rosnufacturer recommends partial flow testing where full-flow testing is undesirable, \ f / j \  % Another event involving the failure of automatic deluge valves took place at Grand Gulf in 1983, and is discussed in Information Notice (IN) 84-16, *Faildte of Automatic Sprinkler System Valves to Operate." While the licensee was performing an operational test of the emergency diesel generator (EDG), a fire occurred in the diesel. Jhe ablomatic deluge valve (6-inch Model C valve manufactured by the Automatic Sprinkler Company of America (ASCO)) failed to open. Approximately 3 months later, a Model Cyatve in a preaction sprinkler system for the 1 EDG room at Grand Gulf failed to operate during a test. In both cases, scoring was found in the actuation weight upper guide collar and in the box t encloses the weight guide bushing. Another instance of repeated failures of'a preaction de valve occurred in 1997 at Limerick Unit 1. A Model *D" 6-inch deluge valve manufactured by Btar Sprinkler, Inc., did not actuate , during a surveillance test. The frequency of testing had been increased because of earlier i failures caused by suspected mpchanical pr6blems. Continued troubleshooting of the valve tailures uncovered a potential v6ttage misr6atch between the deluge valve and the Chemetron release control panel, resulting in marginal power available to operate the valve. The Model "D" valves were subsequently eplaced with Model *G" valves, also manufactured by Star Sprinkler. Related Generic Communications y y e Inform.ation Notice (IN) 8446," Failure of Automatic Sprinkler System Valves to Operate,*% sued M6rch 2,1984. 9 92-28, *lna\ dequgte Fire Suppression System Testing," issued April 8,1992. S' IN 97-22, Totehtial for Failure of the OMEGA Series Sprinkler Heads," issued 

         /      Septener 2'1997.
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 .                                                                                                 IN 99-xx             l
   - .                                                                                             Fsbru ry xx,1999
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This information notice requires no specific action or written response. However, addressees l are reminded that they are required to consider industry-wide operating experience (including NRC information notices) where practical, when setting goals and performing periodic evaluations under 10 CFR 50.65,

  • Requirement for Monitoring the Effectiveness of i Maintenance at Nuclear Power Plants." If you have any questions about the information in this I notice, please contact one of the technical contacts listed below or the propriale Office of Nuclear Reactor Regulation (NRR) project manager. -

f ti 

                                                                                                 'T David B.            hews, Djrector                      ..

Division o Reactor 14ogram Mahegement  ! Office of Reactor Regulation Technical contacts: Mark H. Salley, NRR Robpt Caldwell, Ril I 301-415-2840 3p99 E-mail: mxs3@nrc. gov E-Tnail: rk rc. gov . 

                                                                   "                                                    l William F. Burton, NR .~

301-415-2853 - j-E-mail: wfb@nrc. gov 

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Attachment:

List of Recently issued NRC InforMation Notices 

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