weld defects pocket handbook

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Weld defects handbook

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  • The EverydayPocket Handbook forVisual lnspection andWeld Discontinuities-Gauses and Remedies

    @ Number 2 In a serles

    Complled as a ueeful tool toron-the-lob welding personnel by theAWS Product Development Commlttee

    {

  • @ 2004 by American Welding Society. All rights reservedhinted in the United States of America

    American Wclillm $ocletrNOTE: Although care was taken in choosing and prsenting lhe data in lhis guide, AWS cannot gqamrfe that it i8enor fue. Further, this guide is not intended to be an exhaustive teahnent of the topic and therefore may not include allavailable information, iocluding with rcspert to safety aod health issues. By publishing this guide, AWS does oot insureanyorE using the infomntion it contains against any liability or injury to properry or pe.sors arising fiom tllat us.

    v \ - - 7 v

    Table of ContentsBasic Safety hecautions... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4visual lnspection Notes ......Discontinuity Types:

    Cracks ............ . . . . . . . . . 10Inclusions

    Incomplete Fusion..........,,,.,,,,,...........,,,,,,,.,,...,,,12Incomplete Joint Penetration ............................. 14OverIap...............................................................16Polosity.........................Undercut,.....................

    . . . . . . . . .18tn

    Weld hofi les . . . . . . , .- . . . . . .Fillet Weld Measurement. ..........25Dimensional Considerations .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26Plate ard Pipe Dimensions... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Metdc ConversionNondestructive Testing SymboIs... . . . . . . . . . . . . . . . . . . . . . . . . .31

    30

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    I

  • Basic Safety PrecautionsBurn Protection. Molten metal, sparks, slag,and hot work surfaces are produced by welding,cutting, and allied processes. These can causebums if precautionary measures are not used.Workers should wear protective clothing madeof fire-resistant material. Pant cuffs, open pock-ets, or other places on clothing that can catchand retain molten metal or sparks should not beworn. High-top shoes or leather leggings andfire-resistant gloves should be wom. Pant legsshould be wom over the outside of highlopshoes. Helmets or hand shields that provide pro-tection for the face, neck, and ears, and a headcovering to protect the head should be used. Inaddition, appropriate eye protection should beuseq.

    Electrical Hazards. Electric shock can kill.However, it can be avoided. Live electdcal partsshould not be touched. The manufacturer'sinstuctions and recommended safe practicesshould be read and understood. Faulty installa-tion, improper grounding, and inconect opem-tion and maintenance of electdcal eouiDmentare all sources of danger.

    All elect cal equipment and the workpieceshould be grounded. The workpiece lead isrlot a ground lead. It is used only to completethe welding circuit. A sepamte connection isrcquired to ground the workpiece. The work-piece should not be mistaken for a groundconnection.

    Fumes and Gases. Many welding, cuttmg'and all ied processes produce fumes and gaseswhich mav be harmful to health Avoid breath-ing lhe ai; in lhe fume plume directly above theari. Do not weld in a confined area without aventilation system. Use point-of-welding fumeremoval whin welding galvanized steel, zinc'lead, cadmium. chromium. manganese' brass' orbronze. Do not weld on piping or contalnersthat have held hazardous materials unless thecontainers have been inerted properly'

    Compressed Gas Cylinders' Keep caps oncvlinders when not in use. Make sure that gas

    "ylind"tt ut" chained to a wall or other struc-

    $ral support.

    Radiation. Arc welding may produce ultra-violet, infrarcd, or light radiation Always wearproteclive clothing and ele protection lo pro-iect the skin and eyes from radiation Shieldothers from light rtdiation from your weldingoDeratron.

    AWS also recommends a personal copy of ''Ar-c Welding Safely"' "Fire Safety in Welding and Cut-

    ting". and "safety in Welding. Cutting' and AIlred Processes

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    -.

  • Visual Inspection NotesVisual lnspection is a very effective inspectionmethod, and it should be the primary methodincluded in any effective Quality Control Program. Ithas been shown repeatedly that, "Visual inspection,conducted by properly trained inspectors, resultsin the discovery of the yast majority of thosedefects which would only be discovered later bysome more expensive nondestructive test method."While visual inspection is limited to materials'surface-only examination, it often detects the mostdamaging defects. Visual inspection labbreviated"YT" by the American Society for NondeshuctiveTesting (ASNT)I of welded components requiresinspectors to have a broad knowledge ol many tech-nologie\. including welding. destructive test ing. non-destructive testing, and metallurgy, as well as thecorrect terminoloev for each.

    6

    CracksA crack is defined as "A fracture tvpe discontinuitv characterized P{ i 113":11-1ll':"::il":*'"::i::.t:l}A crack ls dellneo as A' rracrurc LJPE urJlv ' _ :vere discontinuity because ofuni t"ioiit to op""ing displacement " cracks are usuall] ::1tJi:l'^1i1,'^j:t': :1,";, r^^,tion seometrv. rime oflil.l[li:,'."',ifiH?'X11llXl,lTi'li;.iii';'l': -11i'"i'i1':1',r::110^:*T'''*''n seomerr)' rime or::'#:;:'.3 ;";#f

    "',g;i"'i' *' rig"'e below for AwS crack rerminolosv

    It is important to distinguish between the words 'dis-continuity' and 'defect'. Discontinuity refe6 to "Aninterruption of the typical structure of a material,such as a lack of homogeneity in its mechanical,metallurgical, or physical characteristics; a dis.continuity is not necessarily a defect." A defectrefers to "A condition. or conditions. that render apart unable to meet applicable minimum accep-tance standards or specifrcations." All defects arediscontinuities, but not all discontinuities are defects.A defect can be considered a 'rejectable discontinuity'.

    This pocket handbook provides a convenient sourcefor the most comrnon base"metal and weld metaldiscontinuities found by effective VT. The handbookis arranged by discontinuity type, including appli-cable VT detection methods, and likely causes andremedies in addition to suggested repair methods.

    LEGEND:

    3 HEAT.AFFECTEDZONE CBACK

    5 LONGITUDINAL CRACK

    7 BOOT SURFACE CFACK

    1O TBANSVERSE CRACK11 UNDEBBEAD CRACK12 WELD NTEBFACE CFACK13 WELD META! CRACK

    (B)

    I

    b:

  • Types of cracks often include the following prefixes: base metal, cold, crater, delayed, face, heaFaffected zone,hot, hydrogen, intergranular, lamellar tear, longitudinal, quench, root, service induced, stress corrosion, throat,toe, transgranular, tmnsverse, underbead, weld metal, and others.Crack deteciion can be achieved visually ifthe crack is present on the surface and is of sufficient size to be visi-ble to the eye. Smooth, clean surfaces, oblique angle lighting, and a 10x power magnifier are extremely helpfulduring visual inspection for surface cracking. If the surface cracking cannot be found visually, the next step isthe use of the Penetrant Test method (PT). Magnetic Particle Testing (MT) can also be used, but is limited totesting magnetic base materials. Ultrasonic Testing (UT), Eddy Cunent Testing (ET), and Radiographic Testing(RT) are requhed for the detection of subsurface cracking. Ref'er to the AWS Welding Inspection Technologymaterials for more details regarding PT, MT, UT, ET, and RT.Cracking can be caused by a multitude of conditions, but the more common causes are: embrittlement of thebase or weld metal caused by too rapid cooling and the formation of brittle martensite, weld shrinkage stresses,insufficient root bead size, poorjoint design, nonmatching filler metals, and corrosive environment. See fbllowing chart for specific causes and recommended remedies.Repairs to cracks include the following general requirementsll. Locate crack extent and orientation.2. Grind to remove completely; confirm withNDT. Do not weld over (on top ofl crucks.3. Weld using proper procedure, including preheat if required, use small diameter elechodes and stringer bead

    Progression.1. NDT f inished \ eld and ba5e meral.Noter The above procedures may not result in a suitable repair of stress corosion cracking, which may requirereplacement of the affected part or parts.

    neti_ev..esiauai str"tse" mechanically (peening)lfinimize strrinkage stresses using backstep orblock

    i . ra'" i i t .o"Jr"a.t". ' tode negari!e butter rhejoint laces prior to

    craterTa6re;xtEuEhhg the arci use a welding cuffent

  • 10

    lnclusionsInclusions are defined as 'Tntrapped foreign solid material, srrch as slag, flux, tungsten, or oxide." Theinclusions may be found as single particles, aligned particles, or clustered particles. Slag inclusions are fre-quently found on the weld surfaces, or along the toes of the weld due to improper cleaning techniques. Tungsteninclusions are usually subsudace. Examples of inclusions are shown below. Inclusions on the surface can bedetected by VT; subsurface inclusions require UT or RT.

    slag Inclusions (darkened areas)Repairs of inclusions on the surface requke removal by gouging or grinding, welding if required, and reinspec-tion by appropriate NDT method. Subsurface inclusions require removal by gouging or gdnding, followed byweld reoair and reinsoection.

    common Causes and Remedies ot Slag Inclusions

    Causes Remedies

    Failore to remove slag Clean suface and Previous weld bead

    Entrapment of reftactory oxides Power wire brush the Previous weld bead

    Tungsten in the weld metal Avoid contact btween the electrode and the work; use larger electrode

    ImFoperjoi design Increase groove angle ofjoint

    Oxide inclusions Provide proper gas shielding

    Slag flooding ahead of the weldingarc

    Reposition work to prevent loss of slag control

    Poor electrode manipulativetechnique

    Charge electrode or flux to imProve slag control

    Entrapped pieces of electrodecovenng

    Use undamaged electrodes

    l

  • Incomplete Fusion

    Incomplete fusion is defined as "A weld discontinuity inwhich fusion did not occur between weld melal and fusionfaces or adjoining weld beads." Incomplete Fusion (IF) canoccur on both groove welds and fillet welds. The term specifi-cally applies to fillet welds where the weld does not extend tothejoint root. See the figures below.

    Common Causes and Remedies ot Incomplete FusionCauses Remedies

    Insufficient heat input, wrong typeor size of elecrode, improperjointdesign, or inadequate gas shielding

    follow correct welding procedure specificalion

    Incouect electrode position Maintain proper electrode posihon

    Weld metal running ahead of the Reposition work, lower current, or increase weld travel speed

    Trapped oxides or slag on weldgroove or weld face

    Clean weld surface prior to welding

    (c)t 2

    Detection of incomplete fusion usil-' obrique angrerish,,n, *o,o*,"urlr;o"tul-ol #*-r*tl'""""i:i,,n,fi11:;,;;:'J'j;Jl i:ijJffi:

    UT or RT methods.

    Repairs of incomplete fusion rcquire removal of the discontinuity by gouging or grinding, followed by weldrepair and final insDection.

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  • Incomplete Joint PenetrationIncomplete joint penetration is defined as "A joint root condition in a groove weld in which weld metal doesnot extend through the joint thickness." ly'dte that it applies to groore welds only, notJillet welds. Examples ofincompletejoint penetration (IJP) are shown in the following figures.

    ffiINCOMPLETE JOINT PENETRAIION INCOMPLETE JOINT PENETRATION

    Incomplete joint penetration can easily be found by VT if the root of the groove weld is visible; oblique anglelighting assists in its detection. For groove welds with the root not visible, UT or RT are required for detection.Repairs for IJP, when access to the root of the groove weld is possible:1 . Gouge or grind root to an oval, open shape, permitting access to root.2. Weld, followed by appropdate NDT method.Repairs for IJP, where access to the root is not possible:

    1. Couge or ground from the weld face to remove entire weld down to joint root.2. Weld, followed by appropriate I\rDT method.

    tl

    Common Causes and Remedies of Incomplete Joint PenetrationCauses Remedies

    Excessively thick root face orinsuffi cient root opening

    Use proper joint geomety

    lnsufficient hear input Follow welding procedure specification

    Slag flooding ahead of welding arc Adjust electrode or work position

    Electrode diameter |oo large Use smaller electrodes in rool or increase root opening

    Misalignment of second side weld Improve visibility or backgouge

    Failure to backgouge whenspecified

    Backgouge to sound metal if required in welding procedure specification

    Bridging or root opening Use wider root opening or smaller electrode in root pass

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    INCOMPLETE JOINT PENETRAIION

  • OverlapOverlap is defined as "Ihe protrusion of weld metal beyond the weld toe or weld root." Examples are shownbelow for fillet and soove welds.

    t7

    - - - - - -

    t6

    v v v

    Detection of overlap is usually found by VT if the sudaces are visible to the eye; oblique lighting and tox mag-nification are helpful. PI and MT may be required to inspect questionable arcas.Repai$ include removal of overlap by gouging or grinding as a minimum, and may require weld repais to thegouged or ground areas, followed by reinspection using appropriate NDT method.

    OVERLAP

    OVERLAP

    Common Causes and Remedles oI OverlapCauses Remedies

    Slow travel sped Increase travel speed

    Poor electrode madpulation Addirional welder trainilg

    Cravity effects Additional welder training

    o

  • PorosityPorosity is defined as "Cavity-type discontinuities formed by gas etrtrapment during solidilication or in athermal spray deposit." The polosity may be sudace or subsurface, a single cavity, aligned, or clustercd, and isrepresented by the following figues.

    Repaks of porosity consist of removal of the affected area by gouging or gdnding, weld repair, followed by rein-spection by the appropriate NDT method.

    18

    Common Causes and Remedies of PorosityCauses Remedies

    Excessive hydrogen, ninogen, oroxygen i welding atmosphere

    Use low-hydmgen welding process: filler metals high in deoxidizers; increaseshielding gas flow

    High solidification rate Use preheat or increase heat input

    Dirty base metal Clean joint faces and adjacent surfacesDirty filler wire Use specially cleaned and packaged filler wire, and store it in clean area

    Improper arc length, weldingcunent, or electrode manipulation

    Change welding conditions and techniques

    Volatization of zinc from brass Use copper-silicon filler metal; reduce heat input

    Galvanized steel Remove zinc prior to weldingUse 86010 electrodes and manipulate the arc heat to volatilize the zinc ahead ofthe molten weld pool

    Excessive moisture in elecrodecovering or on joint surfaces

    Use recommended procedures for baking and storing electrodesPreheat the base metal

    High sulfur base metal Use electrodes with basic slagging reactions

    l

  • UndercutUndercut is defioed as "A groove melted into the base metal a4iacent to the weld toe or weld face and leftunfilled by weld metal." Exarnples are shown in the followirg figues.

    UNDEBCUT

    Detection of surface undercut is easily found by VT using oblique lighting. 'Catching a thumbnail' in the under-cut groove is also helpful in its detection. Measuement of undercut calr be accurately determined using anundercut gauge showo in the following figure. Intemal undercut on groove welds \there access to the root is notpossible requires UT or RT methods.

    20

    Set bottom of gage on base material. Set poiot on boFtom of undercut. Read depth on scale at pointer.Locking screw can be tightened to hold reading forfuture reference.

    Repahs to ufldercut usually require light g nding andadditional welding to replace the base metal removedduring the undercutting and repair grinding

    l

    ;

    Common Causes and Remedies of Undercut

    Causea Remedies

    Excessive welding cureni Reduce welding cunent

    Excessive Uavel speed Reduce travel speed

    Poor electrode manipulation Additional welder traming

  • Weld ProfilesVisual inspection is very useful in determiniflg the adequacy of weld profiles; the actual welds are comparedwith code or specification requirements rcgarding convexity or concavity for fillet welds, and face and root rei[-forcement for groove welds. The following profiles arc found in AWS D1.1, Structural Welding Code. Addition-ally, fillet weld sizes can be determined using fillet weld gages; theil use is shown on page 25.

    (A) DESIRABLE FILLET WELD PROFILES (B) ACCEPTABLE FILLET WELD PROFILES

    EMNOTE: CONVEXtry C, OF A WELD OR INDIV|DUAL SURFACE BEAD WITH D|MENS|ON W SHALL NOTEXCEED THE VALUE OF THE FOLLOWING TABLE:

    22

    MAXIMUM CONVEXITY OF FILLET WELDSWIDTH OF WELD FACE OR

    INDIVIDUAL SURFACE BEAD, W MAX CONVEXIry CW< Vl6 in. (8 mm)W > 5/16 in. TO W < I in. (2S mm)W> 1 in.

    1/16 in. (1.6 rnm)1/8 in. (3 mm)3/16 in. (5 mm)

    (C) UNACCEPIABLE FILLET WELD PROFILESl l r '

    M M - M1%WWMWMINSUFFICIENT EXCESSIVE EXCESSIVE

    THROAT CONVEXITY UNDERCUTOVERLAP INSUFFICIENT INCOMPLETE

    LEG FUSION

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  • (D) ACCEPTABLE GROOVE WELD PROFILE IN BUTT JOINT

    wBUTT JOINT ff RANSITION)_UNEOUAL THICKNESS PLATE

    AUTT JOINT-EQUAL THICKNESS PLATE

    )

    NOTE: REINFORCEMENT R SHALL NOT EXCEED 1/8 in. (3 mm).

    (E) UNACCEPTABLE GROOVE WELD PROFILES IN BUTT JOINTS

    Fillet Weld MeasurementHow to Use Weld Fillet cage

    rffiffiwrffiEXCESSIVE

    REINFORCEI\,IENTINSUFFICIENT

    THROATEXCESSIVEUNDERCUT

    OVERLAP

    PLACEMENT

    BE CERTAIN BLADEEDGE IS SOUAREWTH WELDED PARTS.

    CONVEX WELDS CONCAVE WELDS

    FOB CONVEX WELDS: USE BLADE W|TH STNGLE ARC ATAPPROPRIATE SIZE. FOB CONCAVE WELDS: USE BLADEWITH DOUBLE ARC ATAPPROPRIATE SIZE.

    425

  • Dimensional ConsiderationsAn important aspect of VT is the measurements for size. geometry, and assembly of welded structures. The manufactwingdrawings will show the required lengths, widths, thicknesses, diameters, elc., ofthe various components, as well as weld sizes.The inspector should determine the dimensional tolerances for each of the measuements specified, and consider them dwingcomponent measurement for conformance. If the tolerances are not stated, the inspector should ask for clarification. Often,these tolerances are noted as 'minimums,"maximums,' or a dimensional mnge such as "1.500 1.750 inches." The inspectorshould also be aware that measurements can be given in the U.S. Customary units, or in the S.l. or metric units.

    Dimensional DetectsIncorrct Joint PreparationL lncorrect joint penetration subject to visual inspection, generally before welding is started, includes out of lolerance

    welding bevel or groove dimensions, base metal misalignment, and undesirable weldjoint fit up conditions.2. Included in the requirements for weld joint preparation shall be inspection for removal of scale, paint. oil. etc., from lhe

    weldjoint.3. Paaial pnetration weldjoint preparadons shall be visually inspected prior b weldirg to assure proper weld drcat dimensions.Incorreca Weld Size1. Incorrect weld size subject to visual inspection includes undersized fillet weld leg dimensions and underfilled groove weld

    throat dimensions.2. Fillet weld size shall be determined by means of a fillet weld gage.

    Incorect Final DimensionsInconect final dimensions subject !o visual inspection include all conditions ofdimensional inaccuracies, distortion, andlack of conformity to design requirements.

    Thickness and Weight of Steel Plates: 1/32-1 inchGage Fraction Decimal mm tb/ft2

    22 t/3) 0.031 o.194 1.2151 6 l /16 0.063 1.588 2.5501 3 3/32 0.094 2.381 3.825l l l/8 0.125 3 .175 5 .1009 5/32 0.156 3.969 6.375,7 3/t6 0 . r88 4.'.763 7.6505 7/32 0.2\9 5.556 8.925l t/4 0.250 6.350 10.200I 9/32 0.28t 't.t44 tt.475

    Not

    5/16 0.3r3 't.931 t2.150|/32 0.344 8.731 t4.0253/8 0.375 9.525 r5.300

    13/32 0.406 10 .319 16.5',75't/t6 0.438 l 2 17.850

    t5/32 0.469 11 .906 19 .125l/2 0.500 12.100 20.400

    Gage Fraction Decimal mm tb/ft2

    Not

    t1/32 0.531 t3.494 21.6',t59/t6 0.563 14.287 22.950

    19/32 0.594 15.081 24.2255/8 o.625 15.875 25.500

    2r/32 0.656 16.669 26.175l l / 16 0.688 17 .463 28.05023/32 0.'7 t9 18.256 29.3253/4 0.750 19.050 r0.600

    25/32 0.?81 t9.8M 31 .8751l/ r6 0.8r3 20.638 33.15021/32 0.844 21.431 34.425t/8 0.875 22.225 J5.700

    29t32 0.906 23.Ot9 36.97515/16 0.s38 23 .813 38.25031t32 0.969 24.606 39.52s

    I 1.000 25.4n 40.800

    A

    #'

  • Thickness and Weight of Steel Plates: 1-2 inchFraction Decimal mm tbftt2t- l /32 1.03t 26.t94 42.0751 l J t6 1.063 26.988 43.350t-1t32 1.094 2't.'781 44.625l-1l8 1.125 28.575 45.900| 5t32 1 .156 29.369 47.n51-3t16 1 .188 30.163 48.450l-'7 t32 1.219 30.956 49.725t-t/4 1.250 31.750 51.0001-9/32 1 .281 32.544 52.2751,5/16 33.338 53.550111 /32 1.344 34.131 54.825r-3/8 t .375 34.925 56.1001-13t32 1.406 35 .719 5',7.3151',7t16 1.438 36 .513 58.650t-t5t32 t.469 31.306 59.9251-1t2 1.500 38 .100 61.200

    28

    Commercial Pipe Sizes and Wall Thicknesses (Asa-836.10 and 836.19)Nominal

    PipeSize

    OutsideDiam.

    Nominal Wall Thicknesses in inches forSched.

    5s1Sched.

    10s rStan-dand2

    Sched.40 xs3

    Sched.80

    Sched.120

    Sched.'t 60

    xxSlronq

    l/8t/4

    0.4050.540

    0.0490.065

    0.0680.088

    0.0680.088

    4.0954.119

    0.0950 . 1 1 9

    3/8t/2 0.840 0.065

    0.0650.083

    0.0910.109

    0.0910.109

    a.1260.147

    o.126u.t4'7 0 .188 o.294

    3/4I

    1.0501 . 3 1 5

    0.0,650.065

    0.0830.109

    0. 30 . 1 3 3

    0 . 1 1 30 .133

    0.1540.179

    0.1540 .179

    0.2r90.250

    0.3060.358

    l-1/41-1/2

    1.6601.900

    0.0650.065

    0.1090.r09

    0.1440.145

    0.1400.145

    0 .1910.240

    0 .1910.200

    0.2500.281

    0.3820.400

    22 1t2

    2.3',752.8',75

    0.0650.083

    0 .1090 .120

    0.1540.243

    0 .1540.203

    0.2180.276

    0 .218o.2'76

    0.3440.375

    0.4360.552

    33 1t2

    3.54.0

    0.0830.083

    0.1200.120

    0.2160.226

    0.2160.226

    0.3000 .3 l8

    0.3000.318

    0.438 0.600

    45 5.563

    0.0830.109

    0.r200.1.34

    0.2370.258

    0.23',70.258

    0.3370.375 0.375

    0.4380.500

    0 .5310.625

    0.6'740.750

    6 6.625 0.109 0 .134 0.280 0.280 0.432 0.432 0.562 0.1t9 0.864NOTES:1 Schedules 5s and los de avail.ble in codosion rcsistant maErials and Schedule los is also lvailable in carbon steel in sizs 12 in. and snaller.2. Thicknes*s shown in ralicr are also available in nainless steel, unde. the desigmtion Schedule 4Os.3. ThickDesses shown in ralicr are aho available in slainles steel. unde! the desilnation Schedule 80s.

    A29

    Fraction Decimal mm lb/ft,t - t7 t i2 1 .531 38.894 62.4751-9/t6 t.563 39.688 63.7501.19/32 1.594 40.481 65.O25I 5/8 1.625 4t.2',75 66._r00t-2v32 1.656 42.069 67.5751 -1 t / 16 1.688 42.863 68.850r 23/32 | .1t9 41.656 70 .125| 3/4 1.750 44.450 71.4001-25t32 1 .781 45.244 12.675l - r3 /16 t . 8 1 3 46.038 13.9501-21t32 |.844 46.831 't5.2251 7/8 1.875 4'7.625 76.5001 29t32 1.906 48.4t9 17.',7',75i - 1 5 / 1 6 r .938 49.2r3 19.O50131 /32 1.969 50.006 80.325

    2 2.000 50.800 8r.600

    *..,

  • Iuletric Converslon Table(Commonly used conversions)

    ----------E

    Propsrty To Convsn From To Multiply byinches': millimete$2 6.452 x t(Pmillimte$2 irches2 1.550 x 10 3

    flow rate feet3/hour litervminute o.472literVmioute feeC/hour 2.119

    lidear inches millimeteIs 25.4millimeters inches 3.931 x loainches centimetels 2.54

    inches o.3937feet 0.305meters feet 3.281

    mass (weight) pounds kilogams 0.454kiloglams pouncls 2.205

    Prssure Psr kilopascal (kPa) 6.895lfa psr 0.L45

    tensile strength psi megapascal (MPa) 6.895 x 10 3MPa psr 1.450 x 1d

    JO

    Examine All Around Fleld Examinatlon Radiation Dlrection

    e

    t

    Nondestructive Testing SymbolsThe examination symbol consists of the following elements:l. Reference line2, Arrow3. Examination method letter designations4, Extent and number of examinations5, Supplementary symbols6. Tail (Sperifications, codes, or other references)

  • Examination Method Letter DesignationsNondesfuctive examination methods shall be specified by use of the letter designation shown below.

    Examlnatlon Method Letler DealgnatlonAET

    Electromagnetic ETLeak LTMagnelic pa$icle MTNeurron radiogaphic NRTPenetmnt PTP{oof PRTRadiographic RTUlEasonic UTVisual VT

    Standard Location ot Elements of a Nondestructive Examination SymbolThe elements of a nondestructive examination symbol shall have standard locations with respect to each other asshowri in the following figue.

    32

    THE-H'550 N.W. LJ6rre Roa4 Mimi, Flo{ide 33 126

    I