SSC-21 3

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A GUIDE FOR ULTRASONIC TESTING ANDEVALUATION OF WELD FLAWS

This document has been approved

for public release and sale; its

distribution is unlimited.

i

SHIP STRUCTURE COMMITTEE

I 970

SHIP STRUCTURE COMMITTEE

MEMBER AGENCIES:

UNITED STATES COAST GUARD

NAVAL SHIP sys TEMs COMMANDMILITARY SEA TRANSPORTATION sERVICE

MARITIME ADMINISTRATION

AMERICAN BUREAU OF SHIPPING

Dear Sir:

10ability in shiphas completed ation quide that

ADDRESS CORRESPONDENCE TO:

SECRETARY

SHIP STRUCTURE COMMITTEE

U.S. COAST GUARD HEADQUARTERS

WASHINGTON, D.C. 20591

1970

maintain the high degree of safety and reli-fabrication, the Ship Structure Committeeproject that provides an ultrasonic inspec-retain~ the comparable radiographic standard

provided earlier.

The results of this project are contained inthis report,

Rear Admiral, U,S. CoastChairman, Ship Structure

GuardCommittee

:!i

,—-,

SSC-213

Final Report

on

Project SR-188,, ‘[UltrasonicTest Guide”

to the

Ship Structure Committee

A GUIDE FOR ULTRASONIC TESTING AND EVALUATIONOF MELD FLAWS

by

R. A. Youshaw

U.S. Naval Ordnance Laboratory

under

Department of the NavyNaval Ship Engineering CenterProject No. SF 35422306

Task 02022

This document haz been approved foY publicrelease and sale; its

dist~ibution is unlimited.

U. S. Coast Guard HeadquartersWashington, D.C.

1970

ABSTRACT

This document presents procedures and acceptance limitsfor contact ultrasonic inspection of steel butt welds in thethickness range of 1/4 to 2 inches. The acceptance limits de-scribed in the following sections are compatible with those setforth in SSC-177, “Guide for Interpretation of NondestructiveTests of Welds in Ship Hull Structures” for radiographic inspec-tion and should therefore result in satisfactory ship welds.

ii

program topertaining

SHIP STRUCTURE COMMITTEE

The SHIP STRUCTURE COMMITTEE is constituted to prosecute a researchimprove the hull structures of ships by an extension of knowledgeto design, materials and methods of fabrication.

RADM W. F. Rea, 111, USCG, ChairmanChief, Office of Merchant Marine Safety

U. S. Coast Guard Headquarters

Capt. Id.R. Riblett, USN Mr. E. S. DillonHead, Ship Engineering Division Deputy ChiefNaval Ship Engineering Center Office of Ship Construction

Maritime AdministrationCapt. T. J. Banvard, USNMaintenance and Repair Officer Mr. C. J. L. $choefer, Vice PresidentMilitary Sealift Command American Bureau of Shipping

SHIP STRUCTURE SUBCOMMITTEE

The SHIP STRUCTURE SUBCOMMITTEE acts for the Ship Structure Committeeon technical matters by providing technical coordination for the determinationof goals and objectives of the program, and by evaluating and interpreting theresults in terms of ship structural design, construction and operation.

NAVAL SHIP ENGINEERING CENTER U. S. COAST GUARD

Mr. J. B. O’Brien - Acting Chairman LCDR C. S. Loosmore, USCG - SecretaryMr. J. B. O’Brien - Contract Administrator CDR C. R. Thom~son. USCG - MemberMr. G. Sorkin - MemberMr. H. S. Sayre - AlternateMr. I. Fioriti - Alternate

MARITIME ADMINISTRATION

Mr. F. Dashnaw - MemberMr. A. Maillar - MemberMr. R. Falls - AlternateMr. W. G. Frederick - Alternate

AMERICAN BUREAU OF SHIPPING

Mr. S. G. Stiansen - MemberMr. F. J. Crum - Member

OFFICE OF NAVAL RESEARCH

Mr. J. M. Crowley - MemberDr. W, G. Rauch - Alternate

NAVAL SHIP RESEARCH & DEVELOPMENT CENTER

Mr. A. B. Stavovy - Alternate

MILITARY 5EALIFT COMMAND

Mr. R. R. Askren - MemberLt. J. G. T. E. I<oster,USN, - Member

LCDR J. W. Kime, U~CG - AlternateCapt. L. A. Colucciello, USCG - Alternat~

NATIONAL ACADEMY OF SCIENCES

Mr. A. R. Lytle, LiaisonMr. R. W. Rumke, LiaisonProf. R. A. Yagle, Liaison

SOCIETYOF NAVAL ARCHITECTS & MARINEENGINEERS

Nr. T. H. Buermann, Liaison

AMERICAN IRON AND STEEL INSTITUTE

Mr. J. R. LeCron, Liaison

BRITISH NAVY STAFF

Dr. V. Flint, LiaisonCDR P. H. H. Ablett, RCNC,

WELDING RESEARCH COUNCIL

Mr. K. H. Koopimn, LiaisonMr. C. Larson, Liaison

Liaison

iii

CONTENTS

SCOPE. . . . . . . . . . . . . . . .

TEST METHOD . . . . . . . . . . . . .

PERSONNEL QUALIFICATION. . . . . . .

CALIBRATION STANDARDS. . . . . . . .

INSTRUMENT CALIBRATION . . . . . . .

WELD INSPECTION. . . . . . . . . . .

DISCONTINUITY LENGTH DETERMINATIONS.

DISCONTINUITY EVALUATION . . . . . .

RECORD OF INSPECTION . . . . . . . .

GLOSSARY OF TERMS. . . . . . . . . .

. . . . . . . . .1

. . . . . . . . .1

. . . . . . . . .3

. . . . . . . . .4

. . . . . . . . .4

. . . . . . . . .5

. . . . . . . . .5

. . . . . . . . .8

. . . . . . . . .8

. . . . . . . . 11

iv

—.

SCOPE

This document presents procedures and acceptance limitsfOr COntact ultrasonic inspect~n of steel butt welds in thethickness range of 1/4 to 2 inches. The acceptance limitsdescribed in the following sections are compatible withthose set forth in SSC-177, “Guide for Interpretation ofNondestructive Tests of Welds in Ship HU1l Structures” forradiographic inspection and should therefore result in satis-factory ship welds. Occasions may arise where radiographicinspection could provide additional information.

TEST METHOD

General - The procedures given apply to the contactultrasonic inspection of butt welds. Weld inspection isaccomplished by introducing shear waves into a Plate at aselected angle and manipulating the transducer so as to scanthe entire weld$ Fig. A-l.

\,/’--

FIG. A-1. TECHNIQUE FOR INSPEC”rIiiGBIJT’ildELESMITH SHEAR WAVES

EuuiPment - The ultrasonic instrument shall be of Ehepulse-echo type with an A-scan presentation. It shall be

capable of generating~ receiving and displaying screen pulsesfrom 1 to 5 MHz on the cathode ray tube. The instrument shallhave a circuitry to provide a continuously increasing ampli-fication with respect to time or distance of travel. Acalibrated decibel attenuator control is recommended. Battery

-.—

-2-

powered equipment must contain an alarm to signal batterydepletion prior to instrument shut-off due to battery exhaustion.

Transducers - The maximum dimension (manufacturers’specifications) of the transducer active element shall notexceed one inch. A ratio of 2:1 width to height of the activeelement is recommended. A nominal test frequency of 2.25 MHzis recommended.

Selection of Probes - The primary consideration forselecting a probe shall be the thickness of the plate. Thefollowing shear wave angles are recommended:

70” for plate thicknesses 1/4” to 1/2”

60° or 70° for platie thicknesses 1/2” to 1-1/2’”

45° or 60° for plate thicknesses l-l\2° to 2-112”.

The transducer angle should be checked periodically with theInternational Xnstitute of Welding Test Block, Fig. A-2.

Couplant - A liquid such as glycerin diluted with alcoholor water and to which a wetting agent has been added isrecommended for acoustic coupling between the transducer andthe plate. Most oils are acceptable. For overhead work andfor places of difficult access certain types of grease may

“..

r ,200~r215

–A–41 G ,/’400509 60” L

I-35+ \PLASTICDISC

NOTE: ALL DIMENSIONS IN MILLIMETERS1 INCH=25.4MM

FIG. A-2. INTERNATIONAL INSTITUTE OF WELDING TEST BLOCK FOR ULTRASONIC CALIBRATION

-3-

prove useful. Any couplant should be removed upon completionof the inspection.

Surface l?re~aratioq - The average plate as receiv~ fromthe mill has a surface that is smooth enough for ultrasonicinspection. l?latewith loose scale, flaked paint, excess rust,or pitting will require grinding. After welding, the surfaceof the base metal where the probe is to be manipulated shouldbe cleaned of weld splatter. If surface irregularities on theweld bead interfere with the ultrasonic test or cause diffi-culties in interpretation then the weld bead should be groundreasonably smooth.

Base Metal Inspection - Although the presence of laminationsin the base metal may not be a basis for rejection, thesereflectors may mask a part of the weld from the ultrasonicbeam, Fig. A-3, or cause the operator to incorrectly locatea discontinuity Fig. A-4. Laminations can be detectedultrasonically with a straight beam (longitudinal waves) .When laminations are encountered, the inspection should bemade from the other side of the weld.

Supplement C, Ultrasonic Testing Method, TC-lA RecommendedPracticeJ American Society for Nondestructive Testing, shall apply.Ultrasonic testing may be carried out by a Level 11 operator orby a Level I operator under the direct supervision of a Level 11operator.

\ LAMINATION //

\, x

/’ ‘p ~\// \

\ /~ /

FIG.A-3. MASKING EFFECT OF A BASEMETALLAMINATION

P’T-T\ ~ / ACTLJALDEFFCT ILOCATION

\> INFERRED DEtitCT LOCATION

,/ \/ \

\/’ \

FIG.A-4. POSITIO!IERRORSINTRODUCEDBY BASE.METALLAMINATION

-4-

CALIBRATION STFJJWW13S

A test block shall be prepar- from material experimentallydetermined to be defect free and which is acoustically similarto thq work material. This block should Ix= 1-1/4” thick witha series of 1/16” diameter drilled holes spaced to provide pathlengths equivalent to the longest and shortest path lengths tobe used in the weld inspection. intermediate distances shouldalso be provided. The scanning surfaces should be approximately250 RMS, prepared by the grinding method with the direction ofgrind parallel to the long dimension of the test block. Figure 5illustrates an acceptable design.

SURFACE FINISH ON THE SCANNING SURFACESTO BE

APPROXIMATELY 250RMS PREPARED BY GRINDING METIIODWITH THE DIRECTION OF GRIND PARALLELTO THE LONGDIMENSIONS OF THE BLOCK.

SCANNING SURFACE

i

“~”D f --- ~ -~ ‘~~

2-1/2” 2-3/4’”~1,

2“ 2-1/4”1-1/2” 1-3/4”

J J I4

1 I JSCANNING SURFACE

FIG. A-5. TYPICAL REFERENCE CALIBRATION STANDARD

INSTRUMENT CAL1BRATIOM

Two levels of signal ampli”kude are defined in this Guide -ARL (Amplitude Reject Level) and DIIL (Disregard Level). Thesetwo levels are established as follows:

The delay controls are used to position the initial pulseat the left of the viewing screen at”a location marked zeroon a reticule or screen scale. The instrument range controlscan then be adjusted to display signals from the referencecalibration drilled holes for the distances to be considered.

The distance amplitude correction controls are to beadjusted to compensate for signal loss due to distance oftravel, i.e., the height of signals from all the reference

-5-

drilled holes should be made equal.

When a decibel attenuator is available, the instrumentgain control is to b~ adjusted to sek the equalized signalsZrom the reference reflectors at 40% of full screen heig-n’c~Fig. A-6. The gain is then increased by 6 decibels. At &hissetting, the ARL is 6 decibels above the 40°Aline and the JNKL(scr@~~ ~~%~~ belowwhich indications are to be disregarded)Shall be the 40% line, Fig. A-6.

When a decibel attenuator is not available~ the instrumentgain control is to be adjusted to set the equalized signalsfrom the reference reflectors at S0?4of full screen height,Fig. A-7. l?or&is setting the 40% line shall be the 131Uandthe 80$!line shall be the ARL, Fig. A-7.

In both of the above cases the calibration should bechecked frequently.

Longitudinal defectis are found by directing the sound beamnormal to the length .ofthe weld and moving the tian~ducer backand forth, Fig. A-8, to scan the entire weld. Simulkaneously$the transduce is oscillated through a small angle. me hackand far~h motions should be repeated at intervals which do notexceed 80% of the width of the transducer as the probe is moved.aI.mqthe weld.

Transverse defects are de~~ted as f~~~ows:

For welds ground smooth the transducer isplace~”on top of the weld and moved along its length,Fig. A-g.

b. For welds not ground smooth the transduceris placed alongside and not quite parallel to theweld and moved along the length, Fig. A-10.

The entire weld and heat affected zone should be scanned.The weld should be inspected from both sides of one surface.

kihendiscontinuities are deteeked$ the sound beam =Imuldbe directed so as to maximize %he signal amplitud~. Thetransducer is then moved parallel to the discontimiky andaway from the position of maximum signal amplitud~. Theextremity of the discontinuity is defined as the point atwhich the signal arnplikudedrops to on-half of tihepeakvalue. This point is markd using the center line of the wedgeas an index. In a similar manner, the other extremity is foundand the distance between marks is defined as the length of thediscontinuity. The minimum recordable length of a discontinuityshall be 1/8”.

-6-

J? 40

.—— .- 30

4 .. . .— 20

... - 10I I I I I <1 I I 0

1

FIG. A-6. TYPICAL VIEWING SCREEN CALIBRATIONFOR INSTRUMENTS WITH DECIBEL ATTENUATION CONTROLS

I —. 70

—.— 60

50

I 40

.,— — 30

20

1 10I I I I I I I

r 5

ARL

DRL

ARL

DRL

FIG. A-7. TYPICAL VIEWING SCREEN CALIBRATIONFOR INSTRUMENTS WITHOUT DECIBEL ATTENUATION CONTROLS

NOTE: CALIBRATION IS PERFORMED WITH THE REFLECTION OBTAINEEIFROM THE WALL OF A1/16” DRILLED HOLE USING DISTANCE-AMPLITUDE CORRECTIONS.

-.

-7-

TRAN5DUCER SONIC

) I

(.)

NOTE: USE SIMILAR SCAN PATH ON OPPOSITE SIDE OF MELO 0!4

b)

FIG. A-8. TECHNIQUE FOR INSPECTING BUTT MELDS WITH SHEAR WAVES

FIG. A-9.INSPECTING

SUPPLEMENTARY TECHNIQUE FORBUTT WELDS WHEN THE WELD BEADIS GROUND FLUSH

FIG. A-10, SUPPLEMENTARY TECHNIQUE FORINSPECTING BUTT WELDS WHEN THE WELD BEAD IS

NOT GROUND FLUSH

-8.

DISCONTINUITY EVALUATION

Discontinuities which do not produce signal amplitudesequal to or greatsr than the DRL~ Fig. A-ll$ shall badisregarded.

Disccmtinuities which cause signal amplitudes equal toor greater than the 13RLbut less than the ARL~ rig. .A-12,require a length determinatiofi aridare evaluated as follows:

a. Defects with length greater than ~ T whe~e T isthe khickness of the plate are unacceptable.

b. For multiple indications, where L is the lengthof the larger discontinuity, if the separationdistance is less than 6L then the sum of theadjacent lengths shall not exceed ~ T. If theseparation distance is more than 6L then thecumulative length in any 6“ length of weld shallnot exceed the plate thidwwsss.

Any discontinuity which produces signal amplitudes in excessof the ML, Fig. A-13, is unacceptable.

When base metals of different thicknesses axe weldedtogether the thickness of the thinner member shall be used indeterminations of acceptable limits of discontinuities.

With the ultrasonic instrument calibrated in accordancewith the procedures set forth in this Guide$ usual siqnalamplitudes for specific type weld defects in relakion to theARL and DRL are illustrated in Fig. A-14.

When rejectable conditions are encaunkered$ radiographymay be useful in determining the nature and extent of the

discontinuity.

RECORD OF ll?SPECTXCBEJ

The record of each weld inspection should include:

1.2.3.4.5.6.7.8.9.

10.11.12.13.

Operator’s identityDateInstrument identityTransducer type$ size, frequency and angleIdentification of test objectLocation of the weldType of materialThickness of base plateme of joint and configurationCondition of the weld beadCouplantFlaw dataInspection coverage, including reference points.

-9-

\

n

INDICATIONS BELOW THE DRLLEVEL ARE TO BE DISREGARDED

FIG. A-n. TYPICAL EXAMPLE OF ULTRASONIC INDICATIONS BELOW THE DRL,

\

10090 INDICATIONS EQUAL TO OR GREATER

ARL— so THAN THE DRL LEVEL BUT LESS THAN70

PTHE ARL LEVEL REQUIREA DETERMl-

.— 60 NATION OF DEFECT LENGTH AND-,. 50

“–DRL— 40SEPARATION DISTANCE

. 30

■

1

20

kl

“,. 101 1 1 !1 1 1 I 1 I o

FIG. A-12. TYPICAL EXAMPLE OF ULTRASONIC INDICATIONS BELOW THE DRLBUT LESS THAN THE ARL

I ,-,n loo{

.- 90ARL— so

70

h

,- 60

“ . 50— DRL— 40

., 30

1

.“. —.. “.. 20

101 1 1 1 1 w ! 1

1 0

WELDS WHICH PRODUCE INDICATIONSEQUAL TO OR GREATER THAN THEARL LEVEL ARE REJECTABLE

FIG. A-13. TYPICAL EXAMPLE OF ULTRASONIC INDICATIONS ABOVE THE ARL

-—.—

-1o-WITH THE ULTRASONIC INSTRUMENT CALIBRATED IN ACCORDANCE WITHTHE PROCEDURES SET FORTH IN THIS GUIDE, WELD DEFECTS OF THE

TYPES LISTED WILL USUALLY PRODUCE SIGNAL AMPLITUDES IN RELATIONTO THE ARL AND DRL LEVELS AS SHOWN:

100

CRACKS CRACK LIKE SLAG

- INCOMPLETE PENETRATION PIPING 90

LACI< OF FUSION LINEAR POROSITYmo–

SEVERE POROSITY–MULTIPLE SLAG INCLUSIONS 70

ROUND EDGE SLAG

– CLUSTERED POROSITY 60

50

40-

MILD SCATTERED POROSITY

30

20

10

0

- ARL

- DRL

FIG. A-14. TYPICAL ULTRASONIC SIGNAL AMPLITUDES PRODUCED BY VARIOUS DEFECTS

..—

-11-

GLOSSARY OF TERMS

A-scan

AcousticallySimilar

ACtiV@

Element -

ARL (zunplitudeReiect Level -

Decibel -

DecibelAttenuator -

DelayControls -

DRL (DisregardLevel)

Frt37uencv

Longitudinal1Waves

Megahertz

Pulse Echo -

A method of data presentation on a cathode raytube utilizing a horizontal base line whichindicates elapsed time when reading from leftto right. A vertical deflection from the baseline indicates reflectd signal amplitudes.

The same type of material as that tiobeinspected, or another material which has beenexperimentally proven to have acoustic velocitywithin *3% and an attenuation for shear waves atthe frequency to be used within *0.25 dE1/inchofthe material to be inspected.

The piezo-electrical material in the ultrasonicprobe.

The horizontal level on the cathode ray tubeestablish by calibration. After calibrationthe ARL is 80% full screen height or 6 dB above

the 40°~line if a decibel attenuator is available.

A logarithmic function of the ratio of twovalues. Tn ultrasonics the two values are thesignal amplitude and a reference amplitude.

A gain control calibrated in decibels.

An electronic means of horizontally shifting thepattern obtained on the cathode ray tube.

The horizontal level on the cathode ray tubeestablished by calibration. After calibrationthe DRL is 40% of full screen height.

The number of cycles in a unit of time. Inultrasonics the frequency is usually expressdin Megahertz or MHz (million cycles per second) .

A wave form in which the particle motion isessentially in the same direction as the wavepropagation.

A million cycles per second.

The sending of sound into a material in theform ofof time

spaced pulses and recording the lengthnecessary for each pulse to travel

RMS (RootMean Suuar@)

Resulting~nqle

ScanningSurface

Shear Wave

StraightJ3eam

Transducer

-12-

through the medium and return to the source ofenergy.

A type of average used in describing surfaceroughness.

The angle formed between the ultrasonic beamas it enters a medium of different characteris-tics than the one from which it came and a linedrawn perpendicular to the interface betweenthe two media.

The surface of the base metal where the ultra-sonic probe is manipulated.

A wave form in which the particle motion isperpendicular to the direction of wave travel.

An ultrasonic technique which does not involvean angle. The wave form is longitudinal.

A device for converting energy of one type intoanother. An ultrasonic transducer convertsenergy from electrical to mechanical andvice versa.

-. —. .—

<$]~]Frlsecurity Classification

DOCUMENT CONTROL DATA. R&D(.Security ctasslficatiorx of title, body of abstract and indexing EInnotstron must be entered when the overall report is cfussjf, ed)

1. OQIGINATIN G ACTIVITY (CorPO.Ste author) 2a REPoRT sECURITY C LA SSIF!CATION

ti. 5. NAVAL ORDNANCE LABORATORY ~flc]~~sifjedWhite Oak, Maryland 2b C,WOUF

~. REPORT TITLE

A Guide For Ultrasonic Testing and Evaluation of Meld Fiaws

!.DESCRIPTIVE NOTES (Type of mportsndincltisive dofms)

Final Re~ort--5. AUTHOR(S) (Last name, first name, initial)

R. A. Youshaw

$.REPORT DATE

August, 1970la, CONTRACT OR GRANT NO.

‘p RO’’cTM O-SF 35422306TASK: 02022

c,

d

10. AVAILABILITY/LIMITATION NOTICES

7a. TOTAL NO. OF PAGES 7b. NO, OF REF5

12 09fI, ORIGINATOR-S REPORT NUM@<R(S)

NOLTR 70-85

9b. OTHEW REPoRT NO(S) (Anyothernumbers ffiatfaay tieaseiEnedthis report)

SSC-213 “,——..

DISTRIBUTION OF THIS DOCUMENT, SSC-213, IS UNLIMITED.

Il. SUPPLEMENTARY NOTES 12. SPONSORING MILITARY ACTIVITY

Naval Ship Engineering Center

,3. ABSTRACT

This document presents p~oc~dures and acceptance limits for contactultrasonic inspection of steel butt welds in the thickness range of 1/4 to2 inches. The acceptance limits described in the following sectionsarecompatible with ‘choseset forth in SSC-177, “Guide for Interpretation ofNondestructive Tests of Welds in Ship Hull Structures” for radiographicinspection and should therefore result in satisfactory ship welds.

)D ,!::!. 1473 UNCLASSIFIED—SecurityClassification

——- ... — —

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Secuiitj Classification

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SHIP RESEARCH COMMITTEEMaritime Transportation Research Board

National Academy of Sciences-National Research Council

The Ship Research Committee has technical cognizance of the Ship Structure

Committee[s Research Program. This entails recommending research objectives, preparingproject prospectuses, evaluating proposals, providing liaison and technical guidance,reviewing project reports, and stimulating productive avenues of research.

PROF. R. A. YAGLE, Chairman.PmfQssorof NavalArchitectureUniversityof Miehigan

DR. H, N, !ABRAMSONDzkdor, Dept. of Mechanical SciencesSou’thuesiResearch Inst<tute

MR. W. H. BUCKLEYChief, S+ructu~al Criteria and Loads.Be21Aawsyskems Co.

DR. D, Pi CLAUSINGSeniop ScientistU.S. Steel Corporation

MR. A, E. COXSenior P~og~am ManagerYeuport New Shipbuilding& Dry Dock Co,

MR. J. F. DALZELLSenio? Research EngineerStevens Institute of Technology

DR, W, D. DOTYSenior Reseamh Consu~tantU.S. Steel Corporation

.,1 MR. F. D. DUFFEY

EngineerShipbuildingCorporation

This project was coordinated

MR. D. FAULKNERRe&&rrd2 #4ssoe’i4teMassachusettsInstitute of

Teehno20gy

PROF. W, J, HALLProfessoF of Civil EngineemkgUnivm5ity of I12inois

MR. J, E. HERZL7kbf St~uetura2Design EngineeringSun Slziphu{lding& DFg .??ockCompany

MR. G. E, IKAMPSCHAEFER.JR,Manager, ApplicationEngineeringARMCO Steel Corporation

PROF. B. R. NOTONProf. of Aerospace & CivilWashingtonUniversity

MR. W. W, OFFNERConsultingEnginew

CDR. R. M, WHITE, USCGChief, Ap~Z{ed Enginee~ingu.S. Coast Gua~d Academy

MR. R, W. RUMKEExecukiVe SeeretaqjShip Research Committee

Engineering

Section

under the guidance of the following Advisory

~ Group III, “Metallurgical Studies” membership:

#-PROF. W. J. HALL, Chairman, P~ofe~sor of Civil Engineering,Un.iversi*yof Illinois

DR. D. P. CLAUSING, Senio~ Scientist, U.S. Weel Corporation

DR. W. D. DOTY, senio~ Reseamh Consul-tank,U.S. Steel Corporation

MR. F. D. DUFFEY, We2ding Enginee~, Ingalk S7ziphui2dingCo~poration

MR. G. E. KAMPSCHAEFER, JR., Manager, Application.Enginee~ing,ARMCO Steel CorpoYatiofi

MR. W. N. OFFNER, ConsultingEngineeF

PROF. A. W. PENSE, mofassor of Mekallwgy, Lehigh Univ-i*y

These documents are dist~ibuted by the CZear{nglzous~,Springfield,Vu. 22151. These documents have been announced in the Clearing-house journal U.S. Government Resea?eh & Development Reports

(USGRDR) under the indicated AD numbers.

.SSC-199, Study of the Factors Which.Affeet the Adequacy of High-StrengthLow-AZZoy Steel Weklments for Cargo Ship Hulls by A. L. Lowenberg.E. B. Norris, A. G. Pickett and R. D. Wylie, August 1969.AD 692262.

SSC-200, Index of Ship Stxwetu~e Committee Reports January 1969. AD 683360

SSC-201, Midship Wave Bending Moment in a Model of the Cargo Ship “WolverineState” Running at Oblique Headings in ReguZa~ Waves by M. d.Chiocco and E. Numata. September 1969. AD 695123.

SSC-202, Midship Wave Bending Moments in a Model of the Ca~go Shipltca~iforniaBea~ “ Running at ObZique Headings in Regular Waves byE. Numata and W, F. Yonkers. November 1969. AD 698847.

SSC-203, Annua2 Report of the Ship Structure Committee. November.1969. AD699240.

SSC-204, SimuZated Perfonnanee Testing for Ship Stxweture Components byR. Sherman. 1970. AD 705398.

SSC-205, Structural Design Revieu of Long, Cylindrical, Liquid-Filled Inde-pendent Cargo Tank Barges by C. W. Bascom. 1970. AD 708565.

SSC-206, Permissible Stresses and Their Limitations by J. J. Nibbering. 1970.

SSC-207, Effect of Flame and Mechanical Straightening on Material Propertiesof We2dments by H. E. Pattee, R. M. Evans, and R. E. Monroe. 1970.

SSC-208, Skrnming of Ships: A C~itieaZ Revieu of the Cument State of Know-ledge by J. !?.Henry, and F. C. Bailey. 1970.

SSC-209, Results From Fu%l-SeaZe kleasu~ementsof Midship Bending Stresses onThree i%y Ca~go S?~ips h~ I. J. Walters and F. C. Bailey, 1970.

SSC-210, Analysis of Slamming Data from the “S.S. Wolve?ine Stater’by J.W,Wheaton, C. H. Kane, P. T. Diamant, F. C. Bailey, 1970.

SSC-211, Design & Installation of a Ship Response In.strumntationSy.stQmAboard the Container Vessel S.S. Boston, by R. A, Fain, J. Q.Cragin and B. H. Schofield. 1970.

SSC-212, Ship Response Instrwnentation Aboard the Container Vesse2 S.S.Boston: Results f~om the 1st Opez=ational Season In North AtlanticServiee, by !2.A. Fain, J. Q. Cragin, and B. H. Schofield. 1970.