IR 05000413/1993033

Insp Repts 50-413/93-33 & 50-414/93-33 on 931129-1203.No Violations Noted.Major Areas Inspected:Isi of Pipe Supports & Snubbers & TS Surveillance of Snubbers

ML20059C150
Person / Time
Site:	Catawba
Issue date:	12/23/1993
From:	Blake J, Clou R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20059C148	List: IR 05000413/1993033 ML20059C145
References
50-413-93-33, 50-414-93-33, NUDOCS 9401040409
Download: ML20059C150 (9)

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UNITED STATES

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NUCLEAR REGULATORY COMMISSION i

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yak REGION 11

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g 101 MAR!ETTA STREET, N.W., SUITE HJO

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't j ATLANTA. GEORGIA 303230199 I

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Report Nos.:

50-413/93-33 and 50-414/93-33 Licensee: Duke Power Company

422 South Church Street

Charlotte, NC 28242 i

Docket Nos.:

50-413 and 50-414 License Nos.:

NPF-35 and NPF-52

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Facility Name:

Catawba 1 and 2 l

Inspection Conducted: November 29 to December 3, 1993

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Inspec or:

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.3 ihou Date Signed

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Approved by:

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J f( Blake, Chiaf Date Signed

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9 erials and Processes Section t

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Engineering Branch Division of Reactor Safety

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SUMMARY

Scope:

This routine, announced inspection was conducted in the areas of Inservice

Inspection (ISI) of pipe supports and snubbers and Technical Specification

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Surveillance of Snubbers.

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Results:

In the areas inspected, violations or deviations were not identified.

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Two unresolved items were identified in the area of inspection of pipe

supports for not removing insulation during ISI inspections (Paragraph 2.2)

.i and in the area of concerns about procedures and inspections of snubbers (Paragraph 3).

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9401040409 931229 DR ADOCK 05000413'

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REPORT DETAILS

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1.

Persons Contacted j

Licensee Employees

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• A. Bhatnagar, Component Engineer Manager-

• D. Caldwell, Civil Engineer Supervisor f

• C Cauthen, Component Engineer 1:

J. Coleman, Quality Control (QC) Supervisor

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• J. S. Forbes, Engineering Manager

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• R. Giles, Quality Assurance (QA) ISI Coordinator J

• D. Kimball, Catawba Safety Review Group Manager

• W. McCollum,-Station Manager

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• K. Nicholson, Compliance Specialist

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• G. Robinson, Mechanical Maintenance QA Supervisor i

• J. Stackly, Component Engineer Supervisor e

M. Wiles, QC Inspector

i Other licensee employees contacted during this '.nspection included

craftsmen, engineers, mechanics, technicians, and administrative i

personnel.

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NRC Resident Inspectors

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• R. Freudenberger, Senior Resident Inspector J. Zeiler, Resident Inspector

• Attended exit interview 2.0 Visual Examination of Pipe Support for Inservice Inspection - Unit 1

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2.1 Procedure Review

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The inspector reviewed the procedures listed below to determine whether:

they were consistent with regulatory requirements and licensee commitments.

The' procedures were also reviewed in the areas of

procedure approval, requirements for qualification of examiners, and

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compilation of required records.

i Procedures No.

Rev. No.

Title

'i QAF-9

Pipe Support Installation Inspection-l t

QAF-14

ISI Visual Examination, VT-3 and-VT-4 l

Procedure No. QAF-9 was only partially reviewed because the inspection.

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standards or acceptance criteria for the correct settings of snubbers

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and spring cans referred to QAF-14.

Procedure No. QAF-14 is to provide

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the examination requirements and records in accordance with American

Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV)

Code Section XI, 1980 Edition with Addenda through Winter 1981, for Catawba.

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2.2 Observations of Examination The' licensee provided updated status of pipe support inspections to the inspector as follows:

Class 1 Class 2 Class 3 Total

119 243 Completed

78 242 Remaining

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There were no discrepancies found on class 1 supports. -Th_e discrepancies found for classes 2 and 3 were listed below:

Support No, Rev. No.

ISI Item No.

Pipe Class Discrepancies e

1-R-SA-0029

Fl.02.793

Spring can out of tolerance.

1-R-KC-0515

Fl.03.590

Bushing out of position.

1-R-KC-0555

F1.03.606

Bushing out of position.

_l-R-KC-0875

- 0 Fl.03.624A

- A loose bolt on pipe clamp.

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- Anchor bolts and base plate

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pulled out from

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ceiling.

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The licensee issued Work Requests (WR) to fix the problems for the first three items; - Problem Investigation Process (PIP) No. 1-093-0875 was.

s written for root cause analysis and resolution of the fourth item.

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il To verify the licensee examination process, the inspector observed i

inspections conducted by the licensee examiner and then independently

inspected eight pipe supports 'after the examiner completed the

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examination to see if-any discrepancies were not found or recorded by

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the examiner. The eight pipe supports were in the Auxiliary Feed Water j

System and Steam Vent System. The examination procedures and acceptance

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criteria were Procedure Nos. QAF-9 and 14. The visual inspection:

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included a check for defects including:

distortion, cracks, bent members, and weld failures induced by plant operations; condition of connections to supporting structures; and component settings.

The inspector's observations generally agreed with the information recorded and reported by the licensee's ISI examiner.

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Table 1 Support No.

Rev. No.

Insulation Condition and Findinas 1-R-CA-1596

Hard insulation covered pipe clamp bolts and nuts and welds between pipe clamp and short bars welded to the clamps.

1-R-CA-1597

Hard insulation covered the U-bolt.

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1-R-CA-1598

Hard insulation covered two bolts and nuts next to the pipe.

1-R-SV-1514

Soft insulation covered two bolts and nuts next to the pipe.

The middle bolt and nuts (one of the two bolts next to the pipe) were found to be loose by the licensee's examiner when he lifted up slightly on the opening of the insulation.

1-R-SV-1515

Soft insulation covered two bolts and nuts next to the pipe.

The middle bolt and nuts (one of the two bolts next to the pipe) were found to be loose by the licensee's examiner when he lifted up slightly on the opening of the insulation.

1-R-SV-1516

The jam nut for the extension pipe

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for the snubber was found to be loose. A 4 inch gap was found at the rear bracket between the spherical bearing and washers.

Hard insulation covered two bolts and nuts next to the pipe.

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l - R-SV-1517

Hard insulation avered two bolts and nuts next to the pipe.

1-R-SV-1519

None.

Most of the above supports the pipe clamps were covered by installed hard or soft insulation. There are typically three bolts with nuts in the pipe clamps; these are the load bolt, middle bolt, and end bolt.

The middle bolt and the end bolt are next to the pipe.

During the first I

three support inspections, the NRC inspector noted that the examiner did not attempt to remove insulation for inspection, he only inspected up to the insulation. When the inspector questioned him as to why he did not

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remove insulation for the inspection, he said that it was not required i

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to remove insulation for ISI.

Later, he opened slightly the insulation for two supports.

He found both supports to have loose bolts and nuts in the middle bolts.

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j Per the licensee's QC inspector's and supervisor's. interpretations of j

their procedure and code requirements, there is no need to remove insulation during the ISI except where an integral weld exists between the support members and the pipe such as lugs.

The integral welds are required to be inspected to the requirements of the pipe classes with

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the removal of insulation.

The licensee's bases for not removing

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insulation are-as follows:

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ASME Code,Section XI, IWF-1300(e)

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ASME Reply to Inquiry Item IN90-027 about IWF-1300(c)

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ASME Reply to Inquiry Item IN92-010 about IWF-1300(e)

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The inspector believes that if you don't remove insulation during the -

ISI, you may miss defects either on the members or connections inside

insulation.

The-licensee agreed to-evaluate the problem of not removing insulation during ISI. This item is identified as Unresolved Item 50-413,414/93 33-01, Pipe Insulation Removal During ISI Support

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inspection.

The licensee currently only intends to issue the Work Requests to fix the loose bolts and nuts already identified.

i 2.3 Data Review

Records of completed ISI examinations for the pipe supports listed in Table I were reviewed.

These records were reviewed to determine whether-

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the methods, techniques, and extent of the examination complied with the

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ISI plan and applicable procedure and findings were properly recorded and evaluated by qualified personnel.

2.4 Personnel Qualification Review l

The inspector reviewed personnel qualification documentation for the ISI

examiners, as listed below in Table 2.

These qualifications were

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reviewed in the following areas:

employer's name; person certified; activity qualified to perform; current period of certification; signature of employer's designated representative; basis used for certification; and annual visual acuity; color vision examination, and periodic recertification.

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In the areas inspected, no violations or deviations were identified.

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Table 2 ISI Examiner Qualification (VT-1 to 41

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Initials Qualified Level Certified Period Eye Exam Expires

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TAB II 03/09/92 to 03/09/95 07/29/94 KMW Il 10/14/93 to 10/14/96 09/14/94-

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AL II 07/21/91 to 07/21/94 02/11/94 i

KBG II 09/24/91 to 09/24/94 03/08/94

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JAF II 09/24/91 to 09/24/94 05/25/94 JDB II 07/22/91 to 07/22/94 03/30/94

JHM II 09/24/91 to 09/24/94 03/03/94

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DTM II 03/09/92 to 03/09/95 04/15/94 BMW II 09/24/91 to 09/24/94 02/10/94 MDM II 07/22/91 to 07/22/94 03/15/94 i

HCM II 10/14/93 to 10/14/96 09/20/94 TSM II 09/24/91 to 09/24/94 03/15/94'

PDS II 07/22/91 to 07/22/94 06/17/94 TJW II 07/22/91 to 07/22/94

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'i 3.0 Technical Specification Snubber Inspection - Unit 1

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In accordance with Section 3.7.8 of the Technical Specification, all the snubbers shall be operable.

Per Section 4.7.8'of the same specification, each snubber shall be demonstrated operable by'the.

performance of visual inspection for all the snubbers plus stroking the mechanical snubbers through its full range of travel for six systems

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before or during the each refueling outage.

The six systems are the

systems with the potential dynamic events including the Main Steam System (upstream of the main. steam isolation valves), the Main Steam safety and power-operated relief valves and piping, Auxiliary Feedwater

.i System, Main Steam Supply to the Auxiliary Feedwater Pump Turbine,' and the letdown and charging portion of the Chemical Volume Control (CVC)

'3 System..All safety-related snubbers shall be visually examined to verify snubber operability. At least every 18 months, during shutdown,

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a representative sample of 10 percent, or 37 snubbers, of the total of

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each type (hydraulic, mechanical, or manufacturers) of safety-related

snubbers in use in the plant shall be functionally tested either in

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place or bench tested.

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i Catawba Unit I has 969 snubbers in safety-related piping systems of

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which 20 are hydraulic snubbers and 949 are mechanical snubbers.

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snubbers are to be stroked in the six high temperature o.r high energy

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systems.

The current status of the snubber inspection, functional test,

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and stroke testing in field is shown below.

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Two Anchor / Darling Type snubbers were tested and were I

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acceptable.

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37 Pacific snubbers were tested with one failure.

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additional sample of 18 snubbers had been tested and were acceptable.

The failed snubber was from Support 1-RKC-0814.

i Stroke testing of 280 of 294 snubbers. from the six systems,

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had been completed, with three snubber failures.

The failed snubbers were from Support Nns. 1-R-ND-0226, 1-R-ND-0596, l

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and 1-R-CF-1728.

Evaluation of those three failed snubbers

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determined that they had been. damaged by water.' hammer.

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Visual examination of 900 of 969 snubbers had been

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completed.

Three snubbers failed the visual examination.

Snubbers from Support Nos. 1-A-RN-9403 and 1-1 XC-8652 failed by binding near rear brackets.

The snubber on

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Support 1-R-NC-1767 had paint on the snubber tube about-1

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inch long.

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The licensee used the following procedures to perform visual i

examination, functional testing, field stroking, reinstallation after -

stroking, and maintenance of snubbers.

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Procedure No. MP/0/A/7650/59, Controlling Procedure for

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Support / Restraint Maintenance

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Procedure No. MP/0/A/7650/85, Visual Inspection of. Snubbers-i and Corrective Maintenance j

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Procedure No. MP/0/A/7650/87, Controlling Procedure for Steam Generator Snubber Maintenance / Testing Activities Procedures No. MP/0/A/9650/95, Post Transient. Piping and

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Hanger Inspection Procedurc No. MP/0/A/7650/131, Functional Testing of

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Snubbers

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.The inspector observed inspection of six snubbers by the licensee's snubber inspector. The NRC inspector independently inspected each snubber, after the licensee's inspector, and generally agreed with' the

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. findings.

The six snubbers observed and inspected are listed below in Table 3.

Field stroke testing of the snubber in Support 1-A-NV-4211 was

also observed.

Table 3

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Snubbers Observed and Inspected

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Support No.

Rev. No.

Comments

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l-A-NV-4211

Snubbers No. S/N 13680 i

1-R-NC-ll29 D2 1-R-NC-1603 D2

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l-R-NC-1604

1-R-NC-1767 D3 1-R-NI-4385

During the review of procedure No. MP/0/A/7650/85, Visual Inspection of l

Snubber and Corrective Maintenance, and observation of the snubber field-

inspection performed by the licensee's snubber inspector, the NRC

inspector noticed the following:

l Overall support Inspection

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The current snubber visual inspection procedure does not require the overall inspection for the supporting-

structures, or foundation, to support the snubber function.

'j The supporting structures should include the gang supports.

The procedure only requires visual-examiners to inspect.the l

snubber, pin to pin, which might extend to end attachments.

Currently, the licensee relies on the individual to perform the overall support inspections because this is not a requirement. The concern with not inspecting the overall supporting structure, or foundation, is that damage to the

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overall structure members or connections may impact the operability of the snubber.

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Gap Between the Spherical Bearing (Bushing) and Washers The current inspection procedure and' practice do not inspect-l the gap between the spherical bearing and clevis or washers at the rod end, near the rear bracket, or the piston rod eye

near the pipe clamps Conceivably, with an excessive gap, I

snubber movement or impact due to pipe movement or vibration could cause damage to the rods, pins or washers.

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Cold or Hot Setting Inspection and Record Comparison

There are v requirements in the procedure and to practice'

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in the fi:lu M pection to record the snubber cold or hot settings or,7j ompare them to the design documents to see if

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the snubber nas experienced unusual activities or j

transients.

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Tool to Inspect 4 degrees Alignment Between Center Lines of i

Clamp and SnLbber

Per Section 11.4.4 of Procedure MP/0/A/7650/85, there is a

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requirement to inspect and make sure that the alignment of I

pipe clamps and snubber center lines are within 4 degrees in

each direction.

Snubber in Support 1-R-NC-1604 appears to

be out of alignment between the pipe clamp and snubber. The

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NRC inspector did not see the licensee inspector carry any'

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tool to measure and to make sure that the alignment is

within 4 degrees.

The licensee agreed to evaluate the above concerns and find an appropriate resolution. The concerns shown above are identified as Unresolved item 50-413,414/93-33-02, Concerns with Snubber

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Procedure and Inspection.

4.0 Exit Interview The inspection scope and results were summarized on December 3, 1993, with those persons indicated in paragraph'I.

The inspector described

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the areas inspected and discussed in detail the inspection results listed below.

Proprietary information is not contained in this report.

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Dissenting comments were not received from the licensee.

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(0 pen) Unresolved item 50-413,414/93-33-01, Pipe Insulation Removal

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During ISI Support Inspection.

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(0 pen) Unresolved Item 50-413,414/93-33-02, Concerns with Inadequate Snubber Procedure and Inspection.

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