I50 2857.73. 4851903 .0096484 2 一 INTERNATIONAL STANDARDISO 2857 : 1973 TECHNICAL CORRIGENDUM 1 Published 1990-10-15 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION·MEXKAYHAPOAHAH OPTAHW3ALIWH HO CTAHAAPTИ3ALMW·ORGANISATION INTERNATIONALE DE NORMALISATION Ground thread taps for IsO metric threads of tolerances 4H to 8H and 4G to 6G coarse and fine pitches - Manufacturing tolerances on the threaded portion TECHNICAL CORRIGENDUM 1 Tarauds a filetsrectifiespour filetages metriques/sOdetolerance 4Ha8Het 4Ga6Gapas gros etapas fins-Tolerances d'execution de la partie taille RECTIFICATIFTECHNIQUE1 Technical corrigendum 1 to International Standard ISo 2857: 1973 was prepared by Technical Committee ISO/TC 29, Small tools. Page 1 Clause 1 Line 5, delete""considered as usually"and insert"considered as not usually", UDC 621.993 Ref.No.ISO2857 : 1973/Cor.1 :1990 (E) Descriptors : tools, taps, screw threads, dimensional tolerances. ISO1990 Printed in Switzerliand COPYRIGHTInternational Organizationfor Standardization LicensedbyInformation HandlingServices M-2S-2S 2857-73 4851903 0014677 T iso 'Published 1986-09-15 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION·ME>KAYHAPOAHAROPrAHM3ALMH NO CTAHAAPTW3ALMWW·ORGANISATION INTERNATIONALEDENORMALISATION Ground thread taps for IsO metric threads of tolerances 4H to 8H and 4G to 6G coarse and fine pitches - Manufactured tolerances on the threaded portion AMENDMENT 2 Tarauds a filets rectifies pour filetages métriques /SO de tolerance 4H a 8H et 4G a 6G a pas gros et a pas fins -- Tolerances d'exécutiondelapartietaillee AMENDEMENT2 Amendment 2 to ISO 2857-1973 was prepared by Technical Committee ISO/TC 29, Small tools. Page 6 Delete sub-clause 4.5 and substitute the following : 4.5 Tolerance on pitch The limits of tolerance on the pitch shall be as shown in table 4, which also shows the length over which the measurement shall be made, expressed in number of pitches. Table 4 -- Tolerance on pitch Pitch Measuring length Limits of innumberof tolerance mm of pitches μm 0,25 0,3 12 8f ± 8 1,25 1,5 8 于 1,75 6 于 2 2,5 ± 10 3 ± 12 3,5 ± 13 ± 14 4,5 ± 15 5 ± 16 5,5 ± 17 ISO 2857-1973/A2-1986 (E) 6 ± 18 UDC 621.993 Ref.No.ISO2857-1973/A2-1986(E) Descriptors : tools, cutting tools, taps, screw threads, dimensional tolerances. InternationalOrganizationforStandardization,1986 Printed in Switzerland Price group A PYRIGHT'InternationalOrganizationforStandardization censed by Information Handling Services 4851903 0014678 1 2857-73 ISO2857-1973/A2-1986(E) NOTE - The tolerance on pitch is based on the diametral equivalent of the pitch error, so that, in general, it shall not exceed 10 % of the 5H nut thread pitch diameter tolerance. The measuring length is based on seven pitches which fals within the "normal" fength of thread engagement as thread length to bring it within the scope of practical measurement. Page 7 Clause 6 Last line of the table, delete "Cumulative pitch error T, over any number of threads" and insert "Tolerance on pitch" Pages 8, 10 and 12 Annexes A and B Delete three times : "Cumulative pitch error T, over any number of threads This error is fixed at ± 0,05 % of the considered measuring length with a minimum of ± 0,008 mm." and insertthreetimes : "Tolerance on pitch See 4.5." 2 CoPYRIGHt"international Organization for Standardization Licensed by Information Handling Services