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 PDP. 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 .

The installationof a 14 "slip-on

flange in a pipeline was recently

witnessed by Al Justin, chief

inspectorfor the State of Minne- sota. Tieflange originallyhad a

14-3/4' inside diameter, which

was reduced by welding a 3/4"

ringand machine welding. The

ring, however, separatedfromthel

LII#

flange, giving the appearanceof a Figure 1 Gasket side of flange.

FAILURE crack. Theflange is reported to

ANALYSIS have been manufactured in the People's Republic of China.

OF A Several such flanges have been reported in thefield. All individuals in the

SLI P-ON industry should be on the alertfor theseflanges.

FLANGE The following is a report by Columbus MetallurgicalServices, 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.

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

1. . w--.e.<t- ^. A. .

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

Figure 2: A close-up of the the subject flange.

gasket side showing the

'crack indication.

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 A - 7 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 Eutes.

.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 A ,, , *_ E L macro ot

, - the pipe a raial

__ side section.

W ~ showing E~e

the 4 5 Hl

'crock-.: 1 mi

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: 72,69,70 HRB Ave = Figure 6: Photo showing general

70 HRB microstructure in the main flange (lower

76,78,80 HRB Ave = half). insert (upper half) and weld metal (left

Insert: edge). 25X. Nital etch.

78 HRB

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 NationalBoard Bullefin quired by the ANSI B16 specification, included an article regarding a serious although they do bear the B16 mark.

problem found to exist on 14" slip-on, raised-face flanges. NBBI advises double-checking all flanges

with the marking "China," especially

Since publication, NBBI has learned the before these flanges are placed in service.

problem described is only one of many

associated with flanges from the Peoples Certainly, flanges that have visible surface

Republic of China. discontinuities or incomplete markings

may be easy to see. But the machined

NBBI has been provided with a lab report surfaces of welded flanges can only be

for a 4" weld neck flange SA-105N B16-5 detected through a volumetric form of

with a BHN (Brinell Hardness Number) of NDE. The failure to meet heat treat, up to 500. Also, normalizing and chemis- mechanical or chemical requirements of

try requirements do not meet SA-105 the specifications can only be verified

requirements. through metallurgic examination. .

These flanges have been reported to have This update is being distributed in the

cracks and other surface discontinuities interest of public safety. Future updates

that might make them unfit for service. In will be published as more facts are learned.

addition, there have been reports that

some flanges do not meet thickness Further questions or concerns should be

requirements. NBBI also has been advised directed to A.M. 'Doc" Matthews, Jr. or

through reinspection reports that some R.D. Schueler, Jr. at National Board head- flanges may not bear the markings re- 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 Inspections John McLouglin, late in May

reports of several different types of in Bejing to discuss the problem.

flanges, ranging in sizes from 2 " to 20*

and marked 'China," that do not appear NBBI continues to advise double-checking

to be in accordance with ANSI B16 as all flanges with the marking China,'

markings. especially before these flanges are placed

in service.

As the number of suspect flanges contin- ues to grow, so does the different types of Flanges that have visible surface

problems related to these flanges. discontinuities or incomplete markings

may be easy to see. But the machined

To date, over 7,000 have been removed surfaces of welded flanges can only be

from service, including 1,600 recently detected through a volumetric form of

discovered in a newly-installed pipeline. NDE. The failure to meet heat treat, An injunction has been ordered to cease mechanical or chemical requirements of

work on the pipeline until the flange the specifications can only be verified

problem has been resolved. The remain- through metallurgic examination.

ing 5,200+ flanges have been found

mostly in refineries. NBBI will continue to publish updates as

information is learned. This update is

The president of the China Association of distributed in the interest of public safety.

Boiler and Pressure Vessel Inspection, Center of Boiler & Pressure Vessel Inspec- Further questions or concerns should be

tion & Research of the Ministry of Labour, directed to A.M. 'Doc" Matthews, Jr. or

P.R.C., Wang Hannuo, has agreed to meet R.D. Schueler, Jr. at National Board

with National Board Assistant Director of headquartersfl

Attachment 2 ..

IN 92-68 September 10, 1992 etter VOLUME I - NUMBER 18 - JUNE 1992 Flange Update: McLoughlin Meets Chinese

Boiler/Pressure Vessel Officials

John D. McLoughlin, assistant director of McLoughlin by Mr. Su Rung ji, vice premiie

Inspections,metwithseveral agendesof the of China. Mr. McLoughlin met with Mr.

Chinese government during his recent visit Zheng You Mel, director of the Reception

to the Peoples Republic of China. The visit Bureau, State Council, PRIC, Ms. Fan Jia

was to discuss problems with flanges mnanu- Nian, assistant director of the Reception Bu- factured in China (and distributed to the reau, and several members of the Center of

US.). Boiler and Pressure Vessel Inspection and

Research (representing the Ministry of La- Two meetings were held in Beijing. bor). CBPV[R has been assisting the Na- tional Board in its investigation

On May 28, 1992, McLoughlin met with

officials of the Center of Boilerand Pressure The director of the Reception Bureau was

Vessel Inspection and Research, as well as givencopiesofinformationaccnunulatedaur- representatives of Sha5ad Prvince Over- ing the course of Mr. McLoughlin's investi- seas Trading Corporation, Tian Gong Com- gation and provided witha briefexplanation

pany. and Oine Xinang Nan Xi U Flare of the documents and the significance of

Company. each.

Mr. McLoughlin learned that Ding Xinang Mr. Zheng You Mei reported that Mr. Su

Nan Xi Li has shipped seven to eight con- Rung ji has a great interest in the flange

tainers (each with 17 tons of various types situation. He said the government appreci- and sizes of flanges) to the US. thmugb ated the information provided by the Na- what is believed to be Tacksonville, Florid& tional Board. Mr. Zheng You Mei also said

ShipptngwasreportedlyprovidedbyShanxi that a complete report of the meeting would

Province, Tlan Gong and Billiongold (a be provided to Mr. Su Rung i.

Hong Kong trader with Beijing offices).

The etng concluded after Mr. McLoughln

Mr. Yang Li Min of Shanxi Province Over- provided Mr. Zheng You Mei with recom- seas Trading Corporation reported that the mrendations on steps the government could

base material for these flanges was 25 MN take to assure that steel mills and forging

and possibly 16 MN (both Chinese forging makers produce material and flanges that

specifications) and not the A105 identified meet ASTM and ANSI specfications. The

on both the flanges and material test report. National Board will be advised when or if

these recommnenda tions w-i be implxemnted.

It was stated by Mr. Yang U Min that manu- facturing identification on the flanges was Upon his return to the US., Mr. McLoughlin

specified by Billiongold (the Hong Kong received thelaboratoryresults of blind flange

trader) and not the flange manufacturer. and slip on flange tests that were ordered

prior to his departure. Results of these tests

A scnd meeting was arranged for Mr. are as follows:

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.

M%* NBIonfdLtt? ispubUahed monthly by

According to Mr. McLoughlin:This office 3d of &oilrand Prewuirt

AccordinghecNationalzB V Inp , 10 Crue Ave=ue, has probably accomplished all it can at this

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 09/10/92 All holders of OLs or CPs

Modifications to Ad- for nuclear power reactors.

dress Failures of

Hiller Actuators Upon

A Gradual Loss of

Air Pressure

92-66 Access Denied to NRC 09/01/92 All holders of OLs or CPs

Inspectors at Five Star for nuclear power reactors

Products, Inc. and and all reci pients of

Construction Products NUREG-0040, "Licensee, Con- Research, Fairfield, tractor and Vendor Inspec- Connecticut tion Status Report" (White

Book).

92-65 Safety System Problems 09/03/92 All holders of OLs or CPs

Caused by Modifications for nuclear power reactors.

That Were Not Adequately

Reviewed and Tested

92-64 Nozzl e Ring Settings 08/28/92 All holders of OLs or CPs

on Low Pressure Water- for nuclear power reactors.

Relief Valves

92-63 Cracked Insulators in 08/26/92 All holders of OLs or CPs

ASL Dry Type Transformers for nuclear power reactors.

Manufactured by Westing- house Electric Corporation

92-62 Emergency Response 08/24/92 All U.S. Nuclear Regulatory

Information Require- Commission licensees.

ments for Radioactive

Material Shipments

92-61 Loss of High Head 08/20/92 All holders of OLs or CPs

Safety Injection for nuclear power reactors.

92-60 Valve Stem Failure 08/20/92 All holders of OLs or CPs

Caused by Embrittlement for pressurized water

reactors (PWRs).

OL = Operating License

CP = Construction Permit