ML20072B059

Interim Deficiency Rept Re Underrated Terminal Strips & Use of Terminal Blocks W/O Proper Environ Qualification in Limitorque Valve Operators.Bechtel Has Requested Addl Info from Limitorque Re Qualifying Terminal Block Types

ML20072B059
Person / Time
Site:	Midland
Issue date:	06/07/1983
From:	Jackie Cook CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
10CFR-050.55E, 10CFR-50.55E, 81-01, 81-1, NUDOCS 8306130281
Download: ML20072B059 (12)

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Consumers Power James W Cook 0%8W vic, era,isa., - eroiac,,. e si. ,i.,

and Construction General offices: 1945 West Parnall Road, Jackson, MI 49201 * (517) 788-0453 June 7, 1983 81-01 #12 Mr J G Keppler, Regional Administrator US Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, IL 60137 MIDLAND NUCLEAR C0 GENERATION PLANT DOCKET NOS 50-329 AND 50-330 UNDERRATED TERMINAL STRIPS ON LIMITORQUE VALVE OPERATORS File: 0.4.9.47 Serial: 22219

Reference:

J W Cook letters to J G Keppler, same subject:

1) Serial 11190, dated February 13, 1981

2) Serial 11976, dated April 24, 1981

3) Serial 12041, dated July 8, 1981

4) Serial 13665, dated September 11, 1981

5) Serial 14617, dated November 20, 1981

6) Serial 14690, dated February 12, 1982

7) Serial 17503, dated June 4, 1982

8) Serial 17565, dated August 6, 1982

9) Serial 19070, dated October 22, 1982

10) Serial 20680, dated January 30, 1983

11) Serial 20729, dated March 16, 1983 This letter, as were the referenced letters, is an interim 50.55(e) report concerning the terminal strip voltage ratings on Limitorque valve operators.

Attachment 1 provides a status of the corrective actions in progress to resolve this problem.

Another report, either interim or final, will be sent on or before October 6, 1983.

JWC/WRB/cd

Attachment:

1) MCAR 46, Interim Report 12 " Qualification Concerns for Various Components on Limitorque Valve Operators,"

dated May 18, 1983.

8306130281 830607 PDR ADOCK 05000329 g 91983 OC0583-0030A-MP01 S PDR 95>f 7

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2 Serial 22219 81-01 #12 CC Document Control Desk, NRC Washington, DC RJCook, NRC Resident Inspector

-Midland Nuclear Plant CBechhoefer, ASLB Panel FPCowan, ASLB Panel AS&L Appeal Panel MMCherry, Esq MSinclair BStamiris CRStephens, USNRC WDPaton, Esq, USNRC FJKelley, Esq, Attorney General SHFreeman, Esq, Asst Attorney General WHMarshall GJMerritt, Esq, TNK&J t

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ii5ta8 Attachment 1 Bechtel Associates Professional Corporation ShBECT: MCAR 46 (issued 1/15/81)

Qualification Concerns for Various Components on j Limitorque Valve Operators '

INTERIM REPORT 12 DATE: May 18, 1983 PROJECT: Consumers Power Company Midland Plant Units 1 and 2 Bechtel Job 7220 Description of Deficiency The following deficiencies are covered by MCAR 46:

a) The use of underrated terminal blocks in Limitorque operators b) The use of terminal blocks without proper environmental qualification in Limitorque operators c) Additional concerns regarding qualification of various Limitorque operator components These concerns are detailed below.

A. Underrated Terminal Blocks While replacing a damaged terminal block on a Limitorque operator, Bechtel determined that some of the terminal blocks used for the termination of the leads from the 460 V motor were rated less than 460 V. These Limitorque operators, when used on safety-related valves, must function on an emergency core cooling actuation signal (ECCAS). In addition to being a personnel safety hazard, the potential exists for a short circuit /flashover, which could render the valves inoperative.

B. Environmental Qualification During random inspection for underrated terminal blocks, it was discovered that in some cases terminal blocks from manufacturers not covered by existing qualification reports were used.

Limitorque provided the following information on environmental qualification of terminal blocks in its July 31, 1981, letter.

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Bechtel Associates Professional Corporation NCAR 46 ll$$g7 Interim Report 12 Page 2 The Buchanan 0524 has been qualified by analysis. To supplement the qualification by analysis, Limitorque is currently running a type test on the Buchanan 0524 terminal block. The Buchanan 0824 terminal blocks are not qualified and must be replaced. .

Some of the Limitorque operators having Buchanan 0824 type terminal blocks have been used on safety-related valves located inside containment. These operators must function on an ECCAS.

The potential exists for a terminal block to fail during its

! intended service life because of aging and radiation effects, j

which would render the valve inoperable and prevent proper operation of the safety-related system.

C. Additional Qualification Concerns During June 1982, a random inspection was made of safety-related Limitorque valve operators supplied through various valve manufacturers and installed inside the reactor building. This inspection resulted in various potential concerns regarding qualification of these Limitorque operators.

Summary of Investimation and Historical Background A. Underrated Terminal Blocks

1. The manufacturer's name was the only form of identification found on a damaged terminal block. To order a replacement for the damaged terminal block, it was therefore necessary to measure the block's critical dimensions and compare them with those for blocks listed in Marathon Catalog 10M79.

This comparison indicated that the terminal blocks used for the termination of the leads from the 460 V motor could have been rated less than 460 V. Eighteen Limitorque operators on Bechtel Purchase Order (P.O.) 7220-M-132-AC were inspected, and eight were found to have underrated terminal blocks (Marathon 100 Series and Cinch Jones 140 Series).

! Thus, Bechtel determined that some terminal blocks in Limitorque valve operators may be underrated for their i intended function. The other ten operators inspected had Marathon 300 Series terminal blocks that are correctly rated for the intended service. Purchase Order 7220-M-132 is with Henry Pratt Company for the supply of nuclear service butterfly valves.

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li5too Bechtel Associates Professional Corporation E H 46 Interin Report 12 liSS87

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Page 3

2. Representatives from Limitorque and Henry Pratt visited the Midland jobsite on January 31, 1981. After inspecting the terminal blocks, they confirmed the results of Bechtel's investigation.

3. Random inspection was performed by Limitorque during the week of May 11, 1981, to establish the magnitude of the presence of the underrated terminal blocks in the Limitorque operators. Limitorque provided Bechtel with detailed reports of its inspection. After review of the inspection reports, Bechtel determined that underrated terminal blocks were not used on any Q-listed purchase orders except P.O. 7220-M-132(Q).

4. Seven different types of terminal blocks were identified (Buchanan 0222, 0524, and 0824; Marathon 300 Series; Beau 7600; Kulka 622; and General Electric EB-5) during the random inspection referred to in Item 3 above. All seven types are acceptable for 460 V service.

5. Arrangements were immediately made by Bechtel to inspect any unshipped valves upon receipt at the Midland jobsite for underrated terminal blocks. Inspection results are tabulated in Item B.7 below.

6. Limitorque/ Henry Pratt submitted the terminal block replacement procedure and Certificate of Compliance for the terminal blocks that Bechtel project engineering approved upon review. The actual replacement of all underrated terminal blocks on Limitorque's Purchase Order 7220-M-132(Q) was undertaken by Bechtel construction personnel under the supervision of Limitorque service engineering during the second week of June 1982. The replacement work is now I

complete; all operators on P.O. 7220-N-132(Q) were inspected.

7. Bechtel has received the inspection / replacement report from Limitorque for the work described in Item A.6 above.

8. Limitorque's letter dated June 25, 1981 (Ref: MCAR 46, Interim Report 4, Item A.1), states that terminal block l types Buchanan 0524 and Beau 7600 were previously rated for l 600 V service using the breakdown voltage method of rating.

l A concern was raised because no documents are currently available at Bechtel to support this statement. Limitorque Ol91u

1i5758 Bechtel Associates Professional Corporation I i 5 6 8 7 Mcia 4.

Interim Report 12 Page 4 has now provided additional documentation showing that the terminal blocks in question were previously rated at 750 V and 600 V, respectively.

B. Environmental Qualification

1. During the random inspection of underrated terminal blocks, referred to in Item A.3 above, Buchanan 0824 terminal blocks were found on three Limitorque operators purchased from Westinghouse on P.O. 7220-N-123A for nuclear service stainless steel valves. Voltage rating data submitted by Limitorque for these terminal blocks were found acceptable.

However, these terminal blocks are unacceptable because of Limitorque's previously cited finding that these blocks "are not" environmentally qualified and "must be replaced."

2. According to Limitorque, the use of unqualified terminal block type Buchanan 0824 is limited to P.O. 7220-M-123A(Q)-AC with Westinghouse Electric, based on Westinghouse's specific requirements. These blocks are not qualified and would require replacement with properly qualified terminal blocks. Based on random inspection results, it was concluded that Buchanan 0824 terminal blocks are not used on any other purchase order.

3. Of the seven terminal blocks listed in Item A.4 above, Limitorque stated that terminal blocks types Buchanan 0222,

, Buchanan 0524, Curtis Type L, Marathon 300 Series, and

! General Electric EB-5 were environmentally qualified for inside containment, but were unable to provide the required qualification documentation.

4. Limitorque presently has no specific plans for an environmental testing of the remaining terminal block types Kulka 622 and Beau 7600 for outside containment use.

4 5. Bechtel has completed the review of the environmental qualification documentation submitted by Limitorque for the terminal block types specified in Item B.3 above. On March 31, 1983, project engineering requested Limitorque to provide additional justification for qualifying the terminal block types, e.g., Buchanan 0524, Curtis Type L, Marathon 300 series, and General Electric EB-5. Limitorque will be requested to supply additional information on Buchanan 0222 type terminal blocks by May 31, 1983.

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'.' Ii5758 Bechtel Associates Professional Corporation I i 5 6 8M4AR 46 Interim Report 12 Page 5

6. Bechtel field engineering has generated Nonconformance Report (NCR) 3780 against valves 2MO-1111, 2MO-1101B, and 2MO-1120B purchased from Westinghouse Electric on P.O. 7220-M-123A(Q)-AC, Items 4.2, 5.4, and 5.8, respectively. This NCR was initiated at the request of project engineering because of the presence of an unqualified terminal block, Buchanan 0824.

7. The following 18 new operators were inspected upon receipt from the vendors at the jobsite for the presence of nonconforming terminal blocks as required in Item A.5 above P.O. Number Item (Ouantity) Terminal Block (TB) 7220-J-255A(Q) 23(8) TB Kulka 622 7220-N-117(Q) 5.1(1)* TB Marathon 300 7220-M-117(Q) 5.2(1)* TB Marathon 300 7220-M-117(Q) 5.3(1)* TB Marathon 300 7220-M-117(Q) 5.4(1)* TB Marathon 300 1 7220-M-168(Q) 1.5(1) TB Buchanan 0222 7220-M-398(Q) 1.1(1) TB Kulka 622 7220-M-398(Q) 1.2(1) TB Kulka 622 l 7220-M-398(Q) 3.1(1) TB Kulka 622 7220-N-398(Q) 3.2(1) TB Kulka 622 7220-M-398(Q) 3.3(1) TB Kulka 622

• These valves were converted to manual. To ensure that the surplus operators will not be used in any application, field engineering has tagged the motor operators and placed them on hold until MCAR 46 is closed..

a) All operators listed above are located outside containment.

The terminal blocks' voltage ratings are acceptable.

. b) However, environmental acceptability is pending review and

( acceptability of the Limitorque qualification documentation i

described in Item B.5 above.

C. Additional Qualification Concerns

1. The motor nameplate ambient temperature rating on various motors installed on some Limitorque operators is 40C.

Limitorque has verbally stated that the Class B insulation motors rated for a 40C ambient temperature have not undergone qualification testing in accordance with IEEE Std 382-1971 for the specified normal, accident, and post-accident environment. Class H insulation motors are 0191u

Ii5758 Bechtel Associates Professional Corporation wa 46 Interim Report 12 liS687 Page 6 rated for 50C ambient temperature, but the qualification testing in accordance with IEEE Std 382-1972 for these motors is presently unknown.

2. No identification was evident on certain materials internal to the Limitorque operators (e.g., wiring, insulation, etc). It is not presently known whether these types are qualified for the service conditions.

3. Various orientations of installed operators were observed.

It is not presently known whether the operators are qualified for all installed orientations.

4. Drain plugs on operators were observed to be both in place and removed. Orientation of the operators did not always result in the drain holes being at the lowest point of the installed operator. It is not presently known whether the existence of the drain plug or the orientation of the drain hole is essential to proper operation of the operator or is in conformance with the qualification tests for the operator.

5. Various Limitorque operator limit switch gear frames were observed to be made of a white metal. It is not presently known whether these gear frames are qualified for the service conditions.

6. Information obtained from purchase order files and QVDP files does not agree with the installed components.

7. It is presently not known whether space heaters are qualified or required to be qualified.

8. Various 0-rings are located throughout the actuator. It is not presently known whether these components are qualified for the service conditions.

9. Unidentifiable terminal blocks (nonpower lead connectors inside the operators) were observed in other Limitorque operators. It is not presently known whether these components are qualified for the service conditions.

To discuss concerns listed above, a meeting was held at Limitorque on August 31, 1982. Limitorque has conducted a component qualification document search for each I

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i ii5758 Bechtel Associates Professional Corporation  :

MCAR 46 'll}gg}

Interim Report 12 Page 7 safety-related Limitorque operator. Bechtel review of the subject component identification data is scheduled to be completed by August 1983. However, based on preliminary review of the component identification data, project engineering has initiated purchase of qualified components and Limitorque operators to replace those that are unqualified.

Safety Implications and Reportability

1. Seven of the eight valve operators having underrated terminal blocks are located in the component cooling water and service water systems and are used on safety-related valves. These must function on an emergency core cooling actuation signal. The potential exists for a short circuit /flashover, which could render the valves inoperative.

Based on the potential safety concerns, this item was considered reportable. This deficiency was reported by Consumers Power Company on January 14, 1981, to R. Sutfin, R. Cook, and R. Knop of the Office of Inspection and Enforcement, Region III, U.S.

Nuclear Regulatory Commission, as a reportable deficiency for Midland Plant Units 1 and 2 in accordance with 10 CFR 50.55(e).

2. Of the concerns expressed above, it is believed that Limitorque operators having a motor rating of 40C ambient temperature and Class B insulation have not been qualified for safety-related service inside the containment. Therefore, the operators may not perform their safety functions under postulated post-accident conditions. However, this concern and the remaining concerns listed above should be regarded as indeterminate because insufficient information exists to classify them otherwise. The status of these concerns is still under investigation and is dependent on the results of the Limitorque component qualification document search. The status will be reported accordingly in future interim reports.

i Probable Cause A. Underrated Terminal Block l

l According to Limitorque, it does not stock Marathon 100 Series

' terminal blocks. However, Limitorque believes (according to its January 21, 1981, letter) that when its field service engineer l

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)i5758 Bechtel Associates Professional Corporation E H 46 Interim Report 12 liS687 Page 8 visited the Midland jobsite in November 1977 to increase the number of points on the terminal blocks for 66 operators (P.O. 7220-M-132), he may have procured the subject terminal blocks locally. Limitorque further explained that an additional 20 terminal blocks (140 Series, manufactured by cinch Jones) were shipped to Midland to make up for quantities damaged in an l

earlier shipment. These blocks are similar to Marathon Series 100 blocks and may have been used by the Limitorque service engineer to terminate the 460 V motor leads. According to Limitorque's July 1, 1982, letter, the root cause for the 4 presence of underrated terminal blocks was the lack of adequate training for a newly employed field service engineer.

B. Unqualified Terminal Block According to Limitorque's July 1, 1982, letter, Buchanan 0824 terminal blocks have not been tested for environmental qualification. These terminal blocks were furnished with actuators built'in 1974 to the specific requirements of an individual valve manufacturer. However, the terminal blocks were considered qualified by analysis at the time they were supplied.

The Buchanan 0824 uses nylon construction, which is unacceptable in today's nuclear industry. It is Limitorque's opinion that this terminal block would pass a nuclear qualification test; however, because of the stigma attached to the use of nylon in this application, the terminal block would still be considered unacceptable.

C. Additional Qualification Concerns The additional concerns addressed above are still being evaluated. A discussion on the probable causes of these concerns will be covered in future interim reports.

Corrective Action l A. Underrated Terminal Blocks During Limitorque's June 1982 inspection / replacement trip to the Midland jobsite, all underrated terminal blocks were replaced by correctly rated Marathon 300 Series terminal blocks on operators purchased on p.0. 7220-M-132(Q). The reports from Limitorque and the field covering the inspection / replacement activities and documentation of terminal block types Buchanan 0524 and Beau 7600 0191u

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Ii5758 Bechtel Associates Professional Corporation MCia a li5687 Interim Report 12 l Page 9 1 l

1 have been accepted. Inspection of the P.O. 7220-M-117(Q) '

operators, as reported in Item B.7, on Page 5 indicate that the voltage rating of the terminal block is acceptable. Thus, this deficiency (B.7a) is considered completely resolved.

B. Unqualified Terminal Blocks

1. Limitorque is expected to resubmit the qualification reports by May 31, 1983.

2. The physical verification of the type of the terminal blocks used on each safety-related Limitorque operator will be included together with the inspection process to verify other concerns.

3. Disposition of NCR 3780 is scheduled to be completed by June 30, 1983.

4. Deletion of terminal blocks from Limitorque operators is under review. The decision will be reported in the next interim report.

C. Additional Qualification Concerns The data sheets submitted by Limitorque (based on its document search) are being reviewed by Bechtel. The review is scheduled to be complete by August 1983. Based on the results of this review, the unqualified components / operators shall be replaced with qualified components / operators in accordance with the applicable requirements. Further required action will be reported in future interim reports.

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Bechtel Associates Professional Corporation I i 5 iniW 46 ii5687 Interim Report 12 Page 10 bmitted  : IJ4c4/

e T. Ballweg Mechanical Group Supervisor Approved by: SC -

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E.M7 Hughes ~

Ann Arbor Project Engineer

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Concurrence by: .

M. Fravel Chief Mechanical '

Engineer Concurrence by: - ~-

/ 4 E. Smith Engineering Manager Concurrence by:

M.A. Dietrich gl Project Quality Assurance Engineer l

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