1、Designation: D2562 94 (Reapproved 2015)Standard Practice forClassifying Visual Defects in Parts Molded from ReinforcedThermosetting Plastics1This standard is issued under the fixed designation D2562; the number immediately following the designation indicates the year oforiginal adoption or, in the c
2、ase of revision, 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 This practice covers acceptance criteria for visual in-spection of parts molded from rein
3、forced thermosetting plasticsby compression and transfer molding.1.2 This practice presents word descriptions of possibledefects to serve as a guide for contracts, drawings, productspecifications, and final inspection.1.3 This practice also categorizes different inspection re-quirements for grades o
4、f product quality.1.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standar
5、d to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1There is no known ISO equivalent to this standard.2. Acceptance Criteria2.1 The method and frequency of sampling and the allow-able defects may be previously agreed t
6、o by the purchaser andthe seller.2.2 Dimensions and TolerancesMolded parts shall beinspected for conformance with the dimensions and tolerancesspecified on the product drawing. Parts with any dimensionsfalling outside the specified limits shall be rejected.2.3 InsertsAll inserts, nuts, studs, and lu
7、gs shall not bedamaged in any way, nor coated with molding materials insuch a way as to impair function or mechanical fit. Threads inmolded-in inserts shall be clean, smooth, and free of nicks,tears, or other damage. There shall be no molding material orflash on the threads. If necessary, threaded i
8、nserts may beretapped to clean them or remove flash. Threads containinglocking features may not be retapped.2.4 Molded-In Threads or Cored HolesMolded-in threadsor cored holes shall be free of visible defects, such as nicks,cracks, shorts, etc. Molded-in threads may be retapped orrepaired unless oth
9、erwise specifically noted on the productdrawing.2.5 WorkmanshipWorkmanship shall be in accordancewith good commercial practices.2.6 Critical AreasAreas in which the presence of imper-fections is considered to be detrimental to the proper functionof the part shall be designated as critical areas. The
10、 areas of apart that are critical structurally, aerodynamically, or electri-cally shall be uniform and free of defects as listed in Table 1,if so stated on the product drawing. Critical areas may bedesignated on the product drawing by one of the followingmeans,2.6.1 Encircle critical areas, or2.6.2
11、Cross-hatch areas to designate areas of various levels,or2.6.3 Word description.2.7 Acceptable DefectsUnless otherwise specified, thefollowing defects shall be acceptable in all instances:2.7.1 Ripple SurfaceGenerally occurs in parts moldedfrom long, glass-fiber-filled, high-impact-type plastics. Su
12、ch asurface is a phenomenon resulting from the difference inshrinkage between the resin binder and reinforcement.2.7.2 Shrink-MarkA dimple-like depression in the surfaceof a molding where it has retracted from the mold, and whichhas well-rounded edges. A shrink-mark generally occurs onone surface of
13、 a part where there is a boss, flange, rib, or otherheavy section on the opposite surface. The shrink-mark may becaused by the difference in total shrinkage when there is asudden change in section along the surface of the part.2.7.3 Resin VoidsApplicable to chopped fabric-reinforcedmolding compounds
14、 only, appearing as multiple surface inter-ruptions which conform to the pattern of the cloth weave. Thisis usually due to an insufficient flow or shrinkage of the resin,which fails to fill all of the interstices of the fabric reinforce-ment. These defects occur only at the surface layer of resin in
15、contact with the mold.1This practice is under the jurisdiction ofASTM Committee D20 on Plastics andis the direct responsibility of Subcommittee D20.18 on Reinforced ThermosettingPlastics.Current edition approved . Published September 2015. Originally approved in1966. Last previous edition approved i
16、n 2008 as D2562 94 (2008). DOI:10.1520/D2562-94R15.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.7.4 Surface DiscolorationAn apparent nonuniformity ofa material, evidenced by the appearance of dark streaks.Surface streaks are freq
17、uently caused by incorporation into theplastic of ejector pin lubricant, mold release, or metallic matterabraded from ejector pins.2.7.5 Weld- or Knit-LinesMarks on, or weaknesses in, amolded plastic, formed by the union of two or more streams ofplastic flowing together, that do not result in a brea
18、k orinterruption of the molded surface.2.8 Allowable DefectsDefects which, by nature, content,or frequency, do not affect serviceability of the part. Theseallowable defects shall be fully described as to type, size,number, extent allowed, and spacing. The appropriate accep-tance level (Table 1) for
19、defects in these areas must bespecified. Defects in excess of those listed as allowable in theproduct specifications, drawings, or contracts for the part shallbe cause for rejection.2.9 Repairable DefectsRepairable defects, if any, shallconsist of those which can be repaired without affecting theser
20、viceability of the part, unless otherwise specifically prohib-ited on the product drawing.Acceptable methods of repair shallhave been agreed to previously by the purchaser and the seller,and shall be fully described on the product specifications,drawings, or contracts for parts.TABLE 1 Allowable Def
21、ectsName DefinitionVisual Acceptance LevelsLevel I Level II Level IIIChip a small piece broken off an edge or surface none maximum dimension of break, 3.0mm (18 in.)maximum dimension ofbreak, 6.5 mm (14 in.)Crack an actual separation of the part, visible onopposite surfaces, and extending through th
22、ethicknessnone none noneCrack, surface crack existing only on the surface of the part none maximum length, 3.0 mm (18 in.) maximum length, 6.5 mm(14 in.)Crazing fine cracks at or under the surface of a part none maximum diameter of crazing, 13mm (12 in.)maximum diameter ofcrazing, 25 mm (1 in.)frequ
23、ency to be determined by customerFracture rupture of the plastic surface without completepenetrationnone maximum dimension, 21 mm (1316in.) in diametermaximum dimension, 29 mm(118 in.) in diameterAir bubble air entrapment within and between thereinforcement, usually spherical in shapenone maximum di
24、ameter, 1.5 mm (116in.); 2 per in.2maximum diameter, 3.0 mm(18 in.); 4 per in.2Blister rounded elevation of the surface of a part,with boundaries that may be more or lesssharply defined, somewhat resembling inshape a blister on the human skinnone maximum diameter, 3.0 mm (18in.); height from surface
25、 not to beoutside drawing tolerancemaximum diameter, 6.5 mm(14 in.); height from surfacenot to be outside drawingtoleranceOrange-peel uneven surface somewhat resembling anorange peelnone maximum diameter, 13 mm (1732in.)maximum diameter, 29 mm(118 in.)Pimple small, sharp, or conical elevation on the
26、surface of a partnone none maximum diameter, 3.0 mm(18 in.)Pit (pinhole) small crater in the surface of the part, with itswidth approximately of the same order ofmagnitude as its depthnone maximum diameter, 0.25 mm(0.010 in.); depth less than 10 %of wall thicknessmaximum diameter, 0.50mm (0.020 in.)
27、; depth lessthan 20 % of wall thicknessfrequency to be determined by customerPorosity presence of numerous visible pits (pinholes) none maximum of 25 pits in porousarea of size listed in Level IImaximum of 50 pits inporous area of size listed inLevel IIIWeld- or knit-linea mark on a molded plastic p
28、art formed bythe union of two or more streams of plasticflowing togethernone allowable only if surface is not brokenDry-spot area of incomplete surface film where thereinforcement has not been wetted with resinnone maximum dimension, 10 mm (1332in.)maximum dimension, 13 mm(1732 in.)Foreign inclu-sio
29、n (metal-lic)metallic particles included in a part which areforeign to its compositionnone none, if for electrical use;maximum dimension, 0.8 mm (132in.), 1 per 0.09 m2(1 ft2), if formechanical usenone, if for electrical use;maximum dimension, 1.5mm (116 in.), 1 per 0.09 m2(1 ft2), if for mechanical
30、 useForeign inclu-sion (non-metallic)nonmetallic particles of substance included ina part which seem foreign to its compositionnone maximum dimension, 0.8 mm (132in.); 1 per 0.09 m2(1 ft2)maximum dimension, 1.5mm (116 in.); 1 per 0.09 m2(1 ft2)Resin-pocket an apparent accumulation of excess resin in
31、 asmall localized area within the partnone maximum diameter, 3.0 mm (18in.)maximum diameter, 5.0 mm(316 in.)Short in a laminate, an incompletely filled outcondition.NOTE 1This may be evident eitherthrough an absence of surface film in someareas, or as lighter unfused particles ofmaterial showing thr
32、ough a covering sur-face film, accompanied possibly by thin-skinned blisters.none none noneD2562 94 (2015)23. Acceptance Levels3.1 Visual InspectionEach part shall be checked visuallywithout the aid of magnification. Defects shall be classified asto type and level, as shown in Table 1 (see Note 2).
33、Theacceptable quality level shall be determined by reference to thepart drawing for the applicable acceptance level for allowabledefects. If none of the first three levels (Levels I, II, and III) isconsidered applicable, the level shall be Level IV, and allow-able defects must be specified on the pr
34、oduct drawing. Anyexcess of defects, as specified under the required level, shall because for rejection. Unless otherwise specified, dimensions aresurface dimensions.NOTE 2Typical defects as outlined in the word descriptions of Table1 are illustrated in Fig. 1.23.2 Acceptance Level IPresence of any
35、defects in excessof those listed in Table 1, Level I, shall be cause for rejection.3.3 Acceptance Level IIPresence of more than one defectof those listed in Table 1, Level II, per estimated 10 in.2ofsurface, shall be cause for rejection. No defect area shall be lessthan 2 in. from another.3.4 Accept
36、ance Level IIIPresence of more than two de-fects of those listed in Table 1, Level III, per estimated 5 in.2of surface area, shall be cause for rejection. No defect areashall be less than 1 in. from another.3.5 Acceptance Level IVAny defect not specifically de-fined by size or shape in Levels I, II,
37、 and III, which falls intoa category between Levels I and II or Levels II and III, orbeyond Level III, and is considered acceptable, shall bedesignated as Level IV, and shall be specified on the productdrawing. Any such defect shall be fully described as to size,shape, number, extent, and spacing on
38、 the product drawing,product specification, or contracts for parts.4. Keywords4.1 reinforced thermosetting plastics; visual defects2Full-size (8 by 10-in.) glossy prints of these typical defects are available at anominal charge from ASTM Headquarters. Order Adjunct: ADJD2562.D2562 94 (2015)3FIG. 1 T
39、ypical Defects (see Table 1)D2562 94 (2015)4FIG. 1 Typical Defects (see Table 1) (continued)D2562 94 (2015)5ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised t
40、hat determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapp
41、roved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you
42、feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual r
43、eprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 94 (2015)6
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