Information Notice 1992-68, Potentially Substandard Slip-On, Welding Neck, and Blind Flanges

Potentially Substandard Slip-On, Welding Neck, and Blind Flanges

ML031210730
Person / Time
Site:	Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant
Issue date:	09/10/1992
From:	Rossi C Office of Nuclear Reactor Regulation
To:
References
IN-92-068, NUDOCS 9209030274
Download: ML031210730 (10)

UNITED STATES NUCLEAR REGULATORY

COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 September

10, 1992 NRC INFORMATION

NOTICE 92-68: POTENTIALLY

SUBSTANDARD

SLIP-ON, WELDING NECK, AND BLIND FLANGES

Addressees

All holders of operating

licenses or construction

permits for nuclear power reactors.PurDose The U.S. Nuclear Regulatory

Commission (NRC) is issuing this information

notice to alert licensees

to problems with potentially

substandard

slip-on, welding neck, and blind flanges. It is expected that recipients

will review this information

for applicability

to their facilities

and consider actions, as appropriate, to avoid similar problems.

However, suggestions

contained

in this information

notice are not NRC requirements;

therefore, no specific action or written response is required.Description

of Circumstances

On July 9, 1992, the NRC staff met with a representative

of The National Board of Boiler and Pressure Vessel Inspectors (Board) to discuss the Board's investigation

of problems associated

with flanges that originated

from the People's Republic of China. The Board has received numerous reports of flanges marked "China" that contain cracks, inclusions, and slugged weld repairs, and that were constructed

from two pieces of material.The suspect China flanges were sold to U.S. suppliers

through several trading companies.

Three of the trading companies

identified

were: Billiongold

Company Limited of Hong Kong, Tain Gong Company, and Shanxi Province Overseas Trading Corporation.

The suspect flanges were marked as forgings that complied with the requirements

of the American Society for Testing and Materials (ASTM) Standard A-105, "Specification

for Forgings, Carbon Steel, for Piping Components," and the American National Standards

Institute (ANSI)Standard B16.5, "Dimensional

Standards

for Steel Pipe Flanges and Flanged Fittings." However, the suspect flanges were manufactured

with ring-inserts

welded to the inside diameter of the flange and the outer surfaces were machined.

Consequently, a visual inspection

would not detect either the welding or the two-piece

construction.

Other flanges were found with slugged weld repairs to the flange hub and still others failed to meet the material specification

requirements

for thermal treatment, mechanical

properties, or chemistry.

9209030274 PD P. TE

IN 92-68 September

10, 1992 Discussion

The Board determined

that one Chinese flange manufacturer, of the several known factories

that supply the U.S., shipped more than 110 tons of ASTM A-105, ANSI B16, China flanges to this country. The Board stated that over 7,000 flanges are being removed from refineries

and petro-chemical

plants as a result of failures that occurred during welding, bolting, and hydrostatic

and pre-operational

testing. The Virginia Electric and Power Company informed NRC staff that China flanges are installed

in two of its fossil power plants and others are in its warehouse.

At the time of discussion, Virginia Power had not determined

whether any suspect China flanges are installed

in its nuclear power plants.The NRC does not have evidence that any suspect China flanges have been installed

in U.S. nuclear power plants. However, specific examples and discussions

of the problems are attached for information.

A potentially

substandard "China" flange can pass between two or more distributors

before reaching the end-user facility.

A nuclear power plant could buy a commercial

grade China flange from a distributor

to dedicate the flange for safety-related

use, or safety-related

components

or subassemblies

that contain China flanges could be supplied by licensee-approved

manufacturers

or fabricators.

Establishing

and verifying

procedures

to trace procured equipment

and material to the original manufacturer

or mill is an important

prerequisite

to inspecting

and testing during the dedication

process. It is possible for a licensee to install potentially

substandard

or defective

equipment

or material if it does not adequately

verify that the product can be traced to the original manufacturer.

This information

notice requires no specific action or written response.

If you have any questions

about this matter, please contact the technical

contact listed below, one of the Board representatives

listed on the attachments, or the appropriate

Nuclear Reactor Regulation (NRR) project manager.I-Cha4rles E. ROssi, Director Division of Operational

Events Assessment

Office of Nuclear Reactor Regulation

Technical

contact: Steven M. Matthews, NRR (301) 504-3191 Attachments:

1. 1992 Board article, "Failure Analysis of a Slip-On Flange." 2. Selected 1992 Board "NBBInfdletters." 3. List of Recently Issued NRC Information

Notices

Attachment

1 -'IN 92-68 September

10, 1992 .FAILURE ANALYSIS OF A SLI P-ON FLANGE The installation

of a 14 "slip-on flange in a pipeline was recently witnessed

by Al Justin, chief inspector

for the State of Minne-sota. Tieflange

originally

had a 14-3/4' inside diameter, which was reduced by welding a 3/4" ring and machine welding. The LII#ring, however, separatedfrom

thel flange, giving the appearance

of a Figure 1 Gasket side of flange.crack. Theflange

is reported to have been manufactured

in the People's Republic of China.Several such flanges have been reported in thefield.

All individuals

in the industry should be on the alertfor theseflanges.

The following

is a report by Columbus Metallurgical

Services, Inc. on the failure analysis of a slip-on flange.A 'cracked" 14" diameter slip-on flange was non-destructively

inspected

by using magnetic particle, dye penetrant

and ultrasonic

test methods. The flange was also checked for material chemical analysis and macro and microstructure.

On the basis of the results and observations

reported, the following

conclusion

is drawn: The subject slip-on flange is not an integral forging or a casting. It has been fabricated

by welding and machining

a ring insert within a large diameter flange. The flange "cracked" because the welds between the flange and the insert were inadequate

to withstand

the bolting pressures.

1. .w--.e.<t-

^. A. .Figure 2: A close-up of the gasket side showing the'crack indication.

BACKGROUND

The "cracked" slip-on flange was received by Columbus Metallurgical

Services, Inc. in one piece. It had two diametrically

opposite cracks located on pipe and gasket sides. It has been reported that se% eral such flanges are in the field. The subject flange has the following engraved markings on the outside diameter (OD): "14 300 SO RF B16.5 A105 848 CHINA 02F" To identify the cause of the failure it was planned to perform dye penetrant, dry magnetic particle, ultrasonic

and radiographic

tests on the subject flange.

Attachment

1 IN 92-68 September

10, 1992 NON-DEsTRUCTIVE

TESTS First, the flange was UT tested from the _ _ ;OD. The indications

were rather puzzling because the reflections

were consistently

from a cylindrical

surface about 3.75" from the OD. A dry mag- -netic particle examination

confirmed that the cracks extended more or less continuously

in a circular path. The 7 A -NDT examination

was concluded

with [ 'dye penetrant

tests as shown in the H i --photographs

in Figures 1 through 4. It Figure 3: Pipe side of flange.was quite evident that the flange was not a single piece component.

A large inside diameter (ID) flange was reduced to a 14" ID unit by welding a 0.75" thick ring. The welding faces had been machined.CHEMICAL ANALYSES AND METALLOGRAPHY

The flange was sectioned

into four pieces to obtain specimens

for chemistry, as well as for macro and microscopic

examination.

The original engraved markings have been retained on one of the segments.

The chemical analyses are as follows: C Mn P S Si Cu Sn Ni Cr Mo Al V Main Flange Steel.23 .62 .024 .038 .24 .27 .016 .094 .079 .026 .006 .003 Welded Insert Steel.26 1.02 .017 .039 .28 .063 .003 .050 .046 .032 .008 .000 ANSI/ASTM

A 105.35 .60-1.05 .040 .050 .35 (listed for reference

only)_7 Figure4: A 5Figure : A~~-close-up

of E L A ,, , *_ macro ot , -the pipe a raial__ side section.W ~ showing E~e the 4 5 Hl'crock-. 1 : mi Eutes.

Attachment

I IN 92-68 September

10, 1992 Figure 5 shows the radial macro section of the flange. Note the insert ring welded to the main flange. When another similar piece was further sec-tioned to retrieve specimens

for mounting and polishing, the insert separated

from the main flange. The general microstructure (ferritic-pearlitic)

at 25X (Nital etch) is shown in Figure 6.ROCKWELL HARDNESS TEST Main Flange: 70 HRB Insert: 78 HRB 72,69,70 HRB Ave =76,78,80 HRB Ave =Figure 6: Photo showing general microstructure

in the main flange (lower half). insert (upper half) and weld metal (left edge). 25X. Nital etch.No further work was deemed necessarvO

BULLETIN/WINTER

1992 Attachment

2 IN 92-68 September

10, 1992 VOLUME I -NUMBER 16 -3/27/92 Alert Continues

for Flanges from China The Winter 1992 National Board Bullefin included an article regarding

a serious problem found to exist on 14" slip-on, raised-face

flanges.Since publication, NBBI has learned the problem described

is only one of many associated

with flanges from the Peoples Republic of China.NBBI has been provided with a lab report for a 4" weld neck flange SA-105N B16-5 with a BHN (Brinell Hardness Number) of up to 500. Also, normalizing

and chemis-try requirements

do not meet SA-105 requirements.

These flanges have been reported to have cracks and other surface discontinuities

that might make them unfit for service. In addition, there have been reports that some flanges do not meet thickness requirements.

NBBI also has been advised through reinspection

reports that some flanges may not bear the markings re-quired by the ANSI B16 specification, although they do bear the B16 mark.NBBI advises double-checking

all flanges with the marking "China," especially

before these flanges are placed in service.Certainly, flanges that have visible surface discontinuities

or incomplete

markings may be easy to see. But the machined surfaces of welded flanges can only be detected through a volumetric

form of NDE. The failure to meet heat treat, mechanical

or chemical requirements

of the specifications

can only be verified through metallurgic

examination.

.This update is being distributed

in the interest of public safety. Future updates will be published

as more facts are learned.Further questions

or concerns should be directed to A.M. 'Doc" Matthews, Jr. or R.D. Schueler, Jr. at National Board head-quarters.

\-_a Attachment

2 -IN 92-68 September

10, 1992 NBBInfoletr/VOLUME

I -NUMNER 17- 5/1/92 Number of Suspect Flanges Growing at Alarming Rate The National Board continues

to receive reports of several different

types of flanges, ranging in sizes from 2 " to 20*and marked 'China," that do not appear to be in accordance

with ANSI B16 as markings.As the number of suspect flanges contin-ues to grow, so does the different

types of problems related to these flanges.To date, over 7,000 have been removed from service, including

1,600 recently discovered

in a newly-installed

pipeline.An injunction

has been ordered to cease work on the pipeline until the flange problem has been resolved.

The remain-ing 5,200+ flanges have been found mostly in refineries.

The president

of the China Association

of Boiler and Pressure Vessel Inspection, Center of Boiler & Pressure Vessel Inspec-tion & Research of the Ministry of Labour, P.R.C., Wang Hannuo, has agreed to meet with National Board Assistant

Director of Inspections

John McLouglin, late in May in Bejing to discuss the problem.NBBI continues

to advise double-checking

all flanges with the marking China,'especially

before these flanges are placed in service.Flanges that have visible surface discontinuities

or incomplete

markings may be easy to see. But the machined surfaces of welded flanges can only be detected through a volumetric

form of NDE. The failure to meet heat treat, mechanical

or chemical requirements

of the specifications

can only be verified through metallurgic

examination.

NBBI will continue to publish updates as information

is learned. This update is distributed

in the interest of public safety.Further questions

or concerns should be directed to A.M. 'Doc" Matthews, Jr. or R.D. Schueler, Jr. at National Board headquartersfl

Attachment

2 ..IN 92-68 September

10, 1992 VOLUME I -NUMBER 18 -JUNE 1992 etter Flange Update: McLoughlin

Meets Chinese Boiler/Pressure

Vessel Officials John D. McLoughlin, assistant

director of Inspections,metwithseveral

agendesof

the Chinese government

during his recent visit to the Peoples Republic of China. The visit was to discuss problems with flanges mnanu-factured in China (and distributed

to the US.).Two meetings were held in Beijing.On May 28, 1992, McLoughlin

met with officials

of the Center of Boilerand

Pressure Vessel Inspection

and Research, as well as representatives

of Sha5ad Prvince Over-seas Trading Corporation, Tian Gong Com-pany. and Oine Xinang Nan Xi U Flare Company.Mr. McLoughlin

learned that Ding Xinang Nan Xi Li has shipped seven to eight con-tainers (each with 17 tons of various types and sizes of flanges) to the US. thmugb what is believed to be Tacksonville, Florid&ShipptngwasreportedlyprovidedbyShanxi

Province, Tlan Gong and Billiongold (a Hong Kong trader with Beijing offices).Mr. Yang Li Min of Shanxi Province Over-seas Trading Corporation

reported that the base material for these flanges was 25 MN and possibly 16 MN (both Chinese forging specifications)

and not the A105 identified

on both the flanges and material test report.It was stated by Mr. Yang U Min that manu-facturing

identification

on the flanges was specified

by Billiongold (the Hong Kong trader) and not the flange manufacturer.

McLoughlin

by Mr. Su Rung ji, vice premiie of China. Mr. McLoughlin

met with Mr.Zheng You Mel, director of the Reception Bureau, State Council, PRIC, Ms. Fan Jia Nian, assistant

director of the Reception

Bu-reau, and several members of the Center of Boiler and Pressure Vessel Inspection

and Research (representing

the Ministry of La-bor). CBPV[R has been assisting

the Na-tional Board in its investigation

The director of the Reception

Bureau was givencopiesofinformationaccnunulatedaur- ing the course of Mr. McLoughlin's

investi-gation and provided witha briefexplanation

of the documents

and the significance

of each.Mr. Zheng You Mei reported that Mr. Su Rung ji has a great interest in the flange situation.

He said the government

appreci-ated the information

provided by the Na-tional Board. Mr. Zheng You Mei also said that a complete report of the meeting would be provided to Mr. Su Rung i.The etng concluded

after Mr. McLoughln provided Mr. Zheng You Mei with recom-mrendations

on steps the government

could take to assure that steel mills and forging makers produce material and flanges that meet ASTM and ANSI specfications.

The National Board will be advised when or if these recommnenda

tions w-i be implxemnted.

Upon his return to the US., Mr. McLoughlin

received thelaboratoryresults

of blind flange and slip on flange tests that were ordered prior to his departure.

Results of these tests are as follows: A scnd meeting was arranged for Mr.

Attachment

2 -P IN 92-68 September

10, 1992 NBBIfoletterivowUmg

1 -NUMUER is-Jums 1992 Flanges continued 1.Blind flange withanidentific

of'PP` and-ked A1O is reported to be aplatemate- riaL 2Slip on flange with an identifier

of USC or UlSIO and a heat #1406 contains slugged weld repairs. The W weld repair indicator required by AIOS Is not stapTed on the flange. The chemistry

does not eet A105.The mill report does not indicate any type of heat treat even though the flange is marked -AIO5N and has also been weld repaired.

'Finally, photo micographs

indicate plate \ \materiaL The flange makers name is Shou '_Roles Gang Machinery

Engineering

Company.According

to Mr. McLoughlin:This

office M%* NBIonfdLtt?

is pubUahed monthly by AccordinghecNationalzB

3d of &oilr and Prewuirt has probably accomplished

all it can at this V Inp , 10 Crue Ave=ue, point, with the resources

available.

The Cohlubus, Ohio 4329,(614)

888-2D National Board will publish a spedil edition of Xte National Boad Bulletin that will ad- D.I. MCDonaL dress this problems Hopefully, we will be Exsputivr

Drcw able to report steps the Chinese government

A.KM Doe Matthews, Jr.are taking to insure that their flange prod. ASS3StWt EpAy= Dirctar ucs meet spedficadon.e

PD. Bnreut A, Diractof WUMMhotIS The National Board will be providing

vanr- sC Nbcos ous appropriate

agencies of the US. govern-ment with information

it has acquired through the investigation

processO

I I Attachment

3 IN 92-68 September

10, 1992 LIST OF RECENTLY ISSUED NRC INFORMATION

NOTICES Information

Date of Notice No. Subject Issuance Issued to 92-67 Deficiency

in Design Modifications

to Ad-dress Failures of Hiller Actuators

Upon A Gradual Loss of Air Pressure 09/10/92 All holders of OLs or CPs for nuclear power reactors.92-66 Access Denied to NRC Inspectors

at Five Star Products, Inc. and Construction

Products Research, Fairfield, Connecticut

09/01/92 All holders for nuclear and all reci NUREG-0040, tractor and tion Status Book).of OLs or CPs power reactors pients of"Licensee, Con-Vendor Inspec-Report" (White 92-65 92-64 92-63 92-62 92-61 92-60 Safety System Problems Caused by Modifications

That Were Not Adequately

Reviewed and Tested Nozzl e on Low Relief Ring Settings Pressure Water-Valves Cracked Insulators

in ASL Dry Type Transformers

Manufactured

by Westing-house Electric Corporation

Emergency

Response Information

Require-ments for Radioactive

Material Shipments Loss of High Head Safety Injection Valve Stem Failure Caused by Embrittlement

09/03/92 08/28/92 08/26/92 08/24/92 08/20/92 08/20/92 All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All U.S. Nuclear Regulatory

Commission

licensees.

All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for pressurized

water reactors (PWRs).OL = Operating

License CP = Construction

Permit