1、Designation: D5426 12 (Reapproved 2017)Standard Practices forVisual Inspection and Grading of Fabrics Used for InflatableRestraints1This standard is issued under the fixed designation D5426; the number immediately following the designation indicates the year oforiginal adoption or, in the case of re
2、vision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 These practices cover procedures for the inspection andgrading of coated and uncoated woven flat a
3、nd one-piecewoven (OPW) fabrics, and for the inspection and culling of cutparts made of such fabrics, all of which are used in themanufacture of inflatable restraint cushions.1.2 For ease of reference, the scope, summary of practice,significance and use, apparatus, sampling, procedure, andreport sec
4、tions are listed separately for each inspection prac-tice.Inspection Practice SectionFabric Rolls 7Cut Pieces subsequently, pieces will be cut fromthe rolls and those pieces that contain imperfections restrictedin Tables 1-5 will be culled at that time.5.5 The accuracy in the results from visually i
5、nspectingfabric using these practices is affected by the ability of theinspector to detect, identify, and evaluate the severity of animperfection in a moving fabric or in a cut part. Such abilityTABLE 1 Coating Non-UniformityImperfection DefinitionLimitsMaximum SizeAMinimumSeparationMaximumFrequency
6、BSoftcontaminationthe presence of materials not specified as part of the coatingor fabric within or on the coating layer, such material visiblyappearing to be of small size, smooth in surface texture, andof a thickness that does not protrude significantly above thesurface of the coating layer. Examp
7、les are dirt, smudge, lint,human hair, yarn filaments, and flies and similarly smallinsects. Soft contamination not listed herein shall be from aknown source which is demonstrated to have no adverseeffect on fabric properties.15 mm diameter 2; but none withinthe line where twoOPW inflatablelayers in
8、terfaceHardcontaminationthe presence of non-coating material within or on the coatinglayer, such material visibly appearing to be of small size,smooth in surface texture, and of a thickness that protrudessignificantly above the surface of the coating layer.Examples are metal filings, glass, plastic,
9、 or wood splinters.none none allowedMissingcoatingportions of the coated layer containing exposed base fabric orscrape marks in the coated layer15 mm diameter 2; but none withinthe line where twoOPW inflatablelayers interface-or-5 mm diameter-or-5; but none withinthe line where twoOPW inflatablelaye
10、rs interfaceCoatingtransferthe presence of coating material on the uncoated side,covering one or more yarnsnone allowedBleedthrough the presence of coating material on the uncoated side,between two yarns without covering either yarn35-mm length 500 mm 2Coating slub an irregularly shaped lump of coat
11、ing material on the surfaceof the coated layer resembling a yarn slub15 mm diameter 2 per 400 cm2Spit mark an essentially round spot of coating material on the surface ofthe coated layer in which the coating spot is visibly at ahigher rate of coverage than the surrounding material.15 mm diameter-or-
12、5 mm diameter2 per 400 cm2-or-5 per 400 cm2Heavycoatingstreaka narrow area of fabric, generally in the shape of a lineoriented in the warp direction of the fabric, in which thecoating layer is visibly at a higher rate of coverage than thesurrounding material.5 mm wide No limitLightcoatingcreasea nar
13、row area of light (not missing) and heavy coatingassociated with localized creasing in the fabric, visibly at alower rate of coverage than the surrounding material.5 mm wide 3; but none withinthe line where twoOPW inflatablelayers interfaceLightcoatingstreaka narrow area of light coating (not missin
14、g), generally in theshape of a line oriented in the warp direction of the fabric.5mmwide 1Light coating(except lightcoating streak)a localized amorphous area of fabric in which the coating layeris visibly at a lower rate than the surrounding material.50 100 mm-or-10 mm dia1-or-5AFor diameter call ou
15、ts, an equivalent area is permissibleBPer linear m (yd), or unit of area indicated. For cut pieces, limits apply to cut pieces # 2 meters in longest dimension. For cut pieces 2 meters in longest dimension,multiply limits by 1.5. Per linear m (yd), cut piece, or unit of area indicated.D5426 12 (2017)
16、2can be affected by visual acuity, viewing distance, fabrictraverse speed, lighting conditions, inspector discipline andtraining, and the availability and accuracy of suitable visualaids.5.6 Systematic bias may result from using these practiceswhenever the precision or scale of the visual aids used
17、toidentify and quantify imperfections differs between the pur-chaser and supplier.TABLE 2 Yarn Non-UniformityImperfection DefinitionLimitsMaximum SizeAMinimumSeparationMaximumFrequencyBForeign matter an extraneous interwoven fragment whose size, color, ortexture indicates that it is not of the same
18、material as thefibers in the base fabricnone allowedLoop a continuous full yarn that curls back on itself and protrudesfrom the surface of the fabric (synonym: kink, snag)none allowedAir splice the thicker portion of a yarn resulting from entanglement of thefilaments at the ends of two multifilament
19、 yarns to create acontinuous yarn2 per 400 cm2Blips any short, irregularly shaped or textured portion of anindividual multifilament yarn that has been woven into thefabric, including slough offs, stripbacks, fuzz balls, snarls,kinky filling less than a loop, and slubs35-mm by 2 -mmlength2; but none
20、withinthe line where twoOPW inflatablelayers interfaceShort knot tail a small knob of yarn and associated tails where two yarns aretied together by interlocking loops for the purpose ofmaintaining yarn continuity3-mm diameter 500 mm 2Brokenfilamentan individual filament, separated from a multifilame
21、nt yarnbundle, that lies on the surface of the fabricno limitAFor diameter call outs, an equivalent area is permissible.BPer linear m (yd) or unit of area indicated. For cut pieces, limits apply to cut pieces # 2 meters in longest dimension. For cut pieces 2 meters in longest dimension,multiply limi
22、ts by 1.5.TABLE 3 DiscolorationImperfection DefinitionLimitsMaximum SizeAMinimumSeparationMaximumFrequencyBStain an area of discoloration that penetrates the fabric surface mustbe from a known source which is demonstrated to have noadverse effect on fabric properties or the presence ofmarking ink in
23、 an area of fabric not provided for identificationby an applicable specification.3-mm diameter-or-15 mm diameter10 per 400 cm2-or-2 per 400 cm2Yarn streak discoloration or stain of an individual yarn that does not affectadjacent yarns1000-mm lengthcumulative1AFor diameter call outs, an equivalent ar
24、ea is permissible.BPer linear m (yd) or unit of area indicated. For cut pieces, limits apply to cut pieces # 2 meters in longest dimension. For cut pieces 2 meters in longest dimension,multiply limits by 1.5.TABLE 4 MiscellaneousImperfection DefinitionLimitsMaximum SizeAMinimumSeparationMaximumFrequ
25、encyBHole an opening not characteristic of the normal weave patternwhere one or more yarns is cut, torn, or shiftednone allowedMissing yarn more than one yarn discontinuity resulting in a change inweave patternnone allowedAFor diameter call outs, an equivalent area is permissible.BPer linear m (yd)
26、or unit of area indicated. For cut pieces, limits apply to cut pieces # 2 meters in longest dimension. For cut pieces 2 meters in longest dimension,multiply limits by 1.5.D5426 12 (2017)36. Visual Aids6.1 A calibrated measuring device or clear template ofsufficient size to contain an array of circle
27、s whose diametersequal the length, diameter, separation, or area limits listed inTables 1-5, with labeling corresponding to the terminology foreach imperfection: 3, 10, 15, 35, 50, 200, 225, 300, 400 and500 mm. The template should be positioned such that themaximum number of imperfections is capture
28、d.6.1.1 Dimensions on the measuring device or template shallbe traceable to the National Institute for Standards and Tech-nology (NIST) (or similarly recognized standards facility) viaa master reference standard to ensure accuracy.6.2 Reference photographs of each imperfection listed inTables 1-5 ba
29、sed on ADJD5426.7. Practice for Inspecting Fabric Rolls7.1 ScopeThis practice describes a procedure for theinspection and grading of coated and uncoated woven fabricsused in the manufacture of inflatable restraint cushions.7.2 Summary of Practice:7.2.1 Rolls of fabric are visually inspected for the
30、presenceof imperfections and graded at an inspection station. Rolls offabric are unwound and rewound as the fabric traverses theinspection station, with provision for interruption of the tra-verse for stationary inspection.NOTE 1In accordance with an applicable material specification, fabricis inspe
31、cted full width or within a specified distance of the outer edge ofthe selvage, or if its in one-piece woven fabric within a specified distanceof the visible line created where the two inflatable layers initially interlace.7.2.2 Fabric inspectors grade imperfections for severity interms of their siz
32、e, relative separation, and frequency per unitarea in accordance with Tables 1-5 of these practices.7.2.3 A count of imperfections is recorded, and the roll isfurther processed in accordance with the applicable materialspecification.7.3 Significance and Use:7.3.1 This practice for inspecting rolls o
33、f fabric is used toidentify imperfections on a unit area basis and to flag them inaccordance with an applicable material specification.7.3.2 The suitability of a roll of fabric for further use orprocessing is not determined by the presence or severity ofTABLE 5 Weave Non-UniformityImperfection Defin
34、itionLimitsMaximum SizeAMinimumSeparationMaximumFrequencyBAbrasion a localized concentration of multiple broken filaments. none allowedFold over a hard ridge where a layer is overlapped upon itself where ifapplicable coating integrity is compromisednone allowedLong float a warp or filling yarn exten
35、ding over six or more filling or warpyarns with which it should be interlacednone allowedShort float a warp or filling yarn extending over five or fewer filling or warpyarns with which it should be interlaced5 per 400 cm2; butnone within the linewhere two OPWinflatable layersinterfaceBruise a shift
36、in the squareness of the weave pattern in an area thathas been subjected to impact or pressure35-mm diameter 500 mm 2Tight yarn a yarn with less crimp than surrounding fibers that may createpuckering, which may appear to be shinier or to lie straighterin the weave pattern, or a combination thereof35
37、-mm length 500 mm 2Misweave a change in the weave pattern visually indicated by incorrectinterlacing or incorrect insertion of a single unbroken yarn ora single missing yarn. (includes mispick, missing yarn,wrong draw, jerk-in).)1000-mm length 1Filling bar a temporary change in the filling-wise dens
38、ity of the weavepattern that:(synonym: stop/start mark)1. is in compliance with the specified count no limit2. is not in compliance with the specified count none allowedStitching (OPW only) the presence of an inter-lace between two layersof fabric in an area not provided for interlacing by anapplica
39、ble specification.none allowedAFor diameter call outs, an equivalent area is permissible.BPer linear m (yd) or unit of area indicated. For cut pieces, limits apply to cut pieces # 2 meters in longest dimension. For cut pieces 2 meters in longest dimension,multiply limits by 1.5.D5426 12 (2017)4imper
40、fections, but by the limits placed on rolls of fabric, if any,in the applicable material specification.7.3.3 This practice for inspecting rolls of fabric does notdifferentiate between rolls of fabric intended for incorporationin driver side, passenger side, or side impact cushions, or forincorporati
41、on in front or rear panels of such cushions.7.3.4 Whenever differences arise between the grading re-sults reported by the supplier and those determined by thepurchaser, entire rolls of fabric are set aside by the purchaser orsupplier for joint visual inspection and grading. Material isaccepted or re
42、jected subsequently by mutual agreement basedon the criteria in this practice and the applicable materialspecification.7.4 Apparatus:7.4.1 A suitable fabric inspection machine that provides aflat viewing surface and an interruptible speed-controlledfabric rewind that measures roll length.7.4.2 An ov
43、erhead, reflected lighting source mounted par-allel to the viewing surface so as to illuminate with directperpendicular impinging light rays and a minimum surfaceillumination level of 1075 lux (100 foot candles), and employ-ing fluorescent lamps having a correlated color temperature of4100 to 4500 k
44、 with white reflectors and without baffles.7.4.3 Optional side-mounted reflected lighting source usedto determine how significantly contamination protrudes fromthe surface of fabric in a roll or a cut piece, mounted obliquelyto the viewing surface so as to illuminate with direct impinginglight rays
45、and a minimum surface illumination level of 1075lux (100 foot candles), and employing fluorescent lampshaving a correlated color temperature of 4100 to 4500 k withwhite reflectors and without baffles.7.4.4 Optional back lighting (transmitted light) or otherauxiliary lighting sources such as ultravio
46、let sources mountedas necessary for optimal visual detection of imperfections in aparticular fabric.7.5 SamplingThis practice for inspecting fabric rolls re-quires 100% inspection of the entire length and surface area ofevery roll of fabric used in the manufacture of inflatablerestraint cushions.7.6
47、 Procedure:7.6.1 Visually inspect and grade the face side of the fabricfrom a viewing distance of 1 m (yd) while the fabric is inmotion.7.6.2 Traverse the fabric longitudinally (warp-wise) throughthe inspection apparatus at a visual inspection speed slowenough to spot imperfections listed in Tables
48、1-5.7.6.3 Using the reference photographs as guides, inspect thetotal length of each roll, interrupting the movement to measurethe size, separation, or frequency of each imperfection.7.6.3.1 Flag each imperfection, signaling its location in thevicinity of the imperfection or along the selvage using
49、only themethod described in the material specification. Flagging de-vices or marks may interfere with subsequent processing. Donot flag imperfections unless the material specification requiresit, and then only in the manner described.7.6.3.2 Unless otherwise specified, if a imperfection extendslonger than 1 m (yd) in the warp direction, flag only itsbeginning and end, but record its entire length in the report.7.6.4 Using the clear template and reference photographs asguides, flag imperfections if they are not allowed according toTables 1-5 or if their size, separation, or freque
