ML20077P891

Supplemental Deficiency Rept CP-87-068 Re Hilti Kwik Bolt (HKB) Inadequacies.Initially Reported on 870824.Plant Installation Revised,Prohibiting Installation of HKBs on on Rotating/Reciprocating Equipment

ML20077P891
Person / Time
Site:	Comanche Peak
Issue date:	08/15/1991
From:	William Cahill TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
CP-87-068, TXX-91288, NUDOCS 9108200126
Download: ML20077P891 (4)

Text

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-- Lo # TXX-91288

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fi e # 10110 903.8 Ref. # 10CFR50.55(e) l TUELECTRIC August 15, 1991  ;

M litiam J. Caliill Jr.

I m un.e i u e theudem l

U. S. Nuclear Regulatory Commission ,

Attn: Document Control Desk '

Washington, DC 20555

$UBJECT: COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)-UNIT 2 ,

DOCKET NO. 50 446 HILTI BOLT INADEQUACIES .

SDAR: CP-87-068 (SUPPLEMENTAL REPORT) l Ref: 1) TV Electric letter from W. G. Counsil to  !

NRC dated February 5,1988, logged TXX i.2174.

2) TU Electric letter from W. J. Cahill Jr. to NRC dated September 21, 1989, logged TXX-89712.  !

t Gentlemen:  !

On August 24, 1987, TV Electric orally notified the NRC of deficiencies involving Hilti Kwik Bolt (HKB) ex)ansion anchors. In Reference 1, l TU Electric described the issue:; witch comprised this SDAR, each of which is summarized below. Reference 2 was the latest Unit I report on this 4 deficiency. This report provides a summary of the Unit 2 corrective actions  ;

for this deficiency.- t The Comanche Peak Response Team (CPRT) identified three trends which comprise ,

this issue: i

1) " bottomed out nuts" and " unacceptable torque" for HKBs on rotating equipment; '

2) lack of Quality Control (QC) documentation on certain HKB ,

installations that were inaccessibic to CPRI personnel due to grout t or topping; and  ;

3) lack of installation documentation relative to the adequacy of QC  ;

monitoring inspection frequencies (10 bolts per shift) for HKB f installations. l t

L CORRECTIVE ACTIONS:

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Rotatina Eouloment (trend no. 1) I Subsequent to identification of trend (1), the Unit 1 installation specification was revised to prohibit installation of HKBs on rotating /

l reciprocating equipment. Unit 1 personnel then examined existing anchorages for the presence of HKBs and issued Nonconformance Reports (NCRs). These HKBs i

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TXX-91288 Page 2 of 4 were then either replaced with a suitable means of anchorage or evaluated as acceptable by Engineering. For those installations evaluated as acceptable, subsequent " torque" and bottomed out nut" verifications were performed by QC.

The Unit 2 installation specification also prohibits the installation of IIKBs on rotating / reciprocating equipment. For Unit 2, TV Evaluation (TVE) forms (formerly NCRs) are issued for existing flKB installations used on rotating / reciprocating equipment. These HKBs will be replaced with a suitable means of anchorage or evaluated as acceptable by Engineering. For those installations evaluated as acceptable, HKB " torque" and " bottomed out nut" verifications will be conducted by QC if inspection documentation does not already exist for these attributes.

Other Commodities (trend nos. 2 and 31 for trend (2), a Corrective Action Report (CAR) was generated to investigate the scope and corrective / preventive actions required for trend resolution.

CAR 87-52 concluded that there was no deficiency associated with this trend because, at the time of the HKB installation in question, the inspection procedure required inspection of a minimum of 10 bolts per shift and that only unsatisfactory inspections be documented. The generic question (trend 3) relative to the adequacy of this inspection method is discussed below.

For trend (3), Unit 1 inspections were conducted for the attributes " torque" and " bottomed out nuts" on other commodities for the purpose of establishing the effectiveness of the 10 bolt per shift inspection frequency and documentation methods. A review of the Unit 1 Post Construction Hardware Validation Program (PCHVP) results has determined that certain commodities inspected in Unit I will not require reverification in Unit 2. These reviews were performed consistent with the " lessons learned" process described in let*er logged TXX-88373, dated April 14, 1988, which indicated that certain attributes reinspected in Unit I would not require reverification in Unit 2.

A summary of the Unit 2 corrective actions by commodity is provided below for these attributes.

Hilti Bolt Torgne A review of the attribute "HKB torque" indicates that the following previously installed Seismic Category 1 commodities do not require torque verifications:

Cable Tray Hangers Conduit Supports Electrical Equipment

TXX-91288 Page 3 of 4 Hilti Bolt Toroue (Cont'd)

Mechanical Equipment Supports Remote Valve Operators (Seismic Cat 11/l)

NF Equipment Supports Pipe Supports Structural Steel Fire Protection Instrumentation and Control Instrument Racks The following Seismic Category I commodity is being redesigned and includes torque setting inspections by QC:

HVAC Duct Supports Existing Seismic Category I commodities determined to require torque verifications by QC include:

HVAC Air Handling Units HVAC Equipment Supports Pipe Whip Restraints Bottomed Out Nut A review of the attribute ' bottomed out nut" indicates that the follow'rg previously installed Seismic Category I commodities do not require verifications:

Cable Tray Hangers Conduit Supports Electrical Eculpment HVAC Air Hancling Units HVAC Equipment Supports Mechanical Equipment Supports Remote Valve Operators (Seismic Cat II/I)

NF Equipment Supports Pipe Supports

• Instrumentation and Control Instrument Racks Fire Protection

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TXX 91288 Page 4 of 4 1

Bottomed Out N_ut (Cont'd) l The following Seismic Category I commodity is being redesigned and  ;

includes " bottomed out nut" inspections by QC: t HVAC Duct Supports ,

Existing Seismic Category I commodities determined to require " bottomed out nut" verif t :ations by QC include:

Pipe Whip Restraints Structural Steel for the commodities above which require reverification of the attributes

" torque" and " bottomed out nut", inaccessible attributes are documented by verifying that QC documentation exists which substantiates the acceptability '

of the installation, or an Attribute Evaluation or TUE Form is initiated and dispositioned by Engineering, ,

Existing Seismic Category 11 installations are addressed as part of the  !

seismic evaluation walkdown which demonstrates the seismic integrity of the .

commodity. Details of this program will be addressed by separate letter describing the Unit 2 corrective actions for SDAR-CP 86-045 " Seismic Category 11 Systems and Components". Any modifications to Seismic Category 11 installations identified as a result of this walkdown will be corrected and verified in accordance with the methodology described in letter logged. TXX- ,

91164, dated April 23, 1991. l The corrective actions associated with the Seismic Category I commodities noted above for the attributes of "HKB torque" and " bottomed out nuts" will be -

completed prior to Unit 2 fuel load.

PREVENTIVE ACTIONS:

Unit 2 installation specifications prohibit the use of HKBs on rotating / '

reciprocating equipment. Additionally, Unit 2 installation specifications provide installation and inspection criteria for torque and nut engagement and ,

establish the required frequency of inspection for HKB installations.  ;

Sincerely, J(

William J. Cahill, Jr.

CLW/RJB:rjb c- Mr. R. D. Martin, Region IV ,

Resident inspectors, CPSES (2) j Mr. T. A. Bergman, NRR Mr. M. B. Fields, NRR

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