237 NTERNATIONAL STANDARD INTERNATIONAL ORGANIZATION FOR STANDARDIZATION ·MEXKIYHAPOHAA OPIAHW3ALIMA HO CTAHIAPTH3ALIWH.ORGANISATION INTERNATIONALE DE NORMALISATION Rotating tools with parallel shanks - Diameters of shanks and sizes of driving squares Outils tournants a queue cylindrique - Diametres des queues et dimensions des carres d'entrainement First edition -- 1975-02-01 UDC 621.9.02 Ref. No. ISO 237-1975 (E) ISO 237-1975 (E) Descriptors : tools, shanks, parallel shanks, driving squares, dimensions, diameters. Price based on 5 pages Copyright International Organization for Standardization nitted without license from IHS Not for Resale No FOREWORD ISO (the International Organization for Standardization) is a worldwide federation of national standards institutes (ISO Member Bodies). The work of developing International Standards is carried out through IsO Technical Committees. Every Member Body interested in a subject for which a Technical Committee has been set up has the right to be represented on that Committee. International organizations, governmental and non-governmental, in liaison with IsO, also take part in the work. to the Member Bodies for approval before their acceptance as International Standards by the ISO Council. Prior to 1972, the results of the work of the Technical Committees were published Recommendations; these documents are now in the process of being as IsO transformed into International Standards. As part of this process, Technical Committee 1SO/TC 29 has reviewed ISO Recommendation R 237 and found it technically suitable for transformation. International Standard ISO 237 therefore replaces ISO Recommendation R 237-1961 to which it is technically identical. countries : Austria Romania India Beigium Italy Sweden Czechoslovakia Mexico Switzerland France United Kingdom Netherlands Germany Pakistan U.S.S.R. Greece Poland Hungary Portugal following country disapproval of the The Member Body of the 1 expressed Recommendation on technical grounds : U.S.A. The Member Body of the following country disapproved the transformation of ISO/R 237 into an International Standard : Austria @ International Organization for Standardization, 1975 : Printed in Switzerland pyrihneationarganizatiStandardizatio Not for Resale d without license from IHS ISO 237-1975 (E) INTERNATIONAL STANDARD Rotating tools with parallel shanks - Diameters of shanks and sizes of driving squares 1 SCOPE AND FIELD OF APPLICATION 2 PREFERRED DIAMETERS This Internationai Standard lays down the shank diameters Millimetres Inches and driving square sizes for rotating tools with parallel shanks, such as reamers, screwing taps, etc. 1,12 11,2 0.440 9 0.044 1 It comprises two series of dimensions, a principal series and 1,25 12,5 0.049 2 0.492 1 secondary series, and gives for each of them the a 1,40 14,0 0.055 1 0.551 2 dimensions in millimetres and the corresponding 0.063 0 0.629 9 1,60 16,0 dimensions in inches. 1,80 18,0 0.070 9 0.708 7 In each of the two series, the dimensions of driving squares 2,00 20,0 0.078 7 0.787 4 for a given shank diameter are shown. 2,24 22,4 0.088 2 0.881 9 The complete range of diameters is divided into a certain 2,50 25,0 0.098 4 0.984 2 number of diameter steps, for each of which the corresponding standard square is given either in the 2,80 28,0 0.110 2 1.102 4 principai series, or in the secondary series for use in cases 3,15 31,5 0.124 0 1.240 2 where a finer subdivision is absoiutely necessary in the 3,55 35,5 1.397 6 0.139 8 small diameters. 4,00 40,0 0.157 5 1.5748 In the metric tables, the values of the across flats a of the 4,50 45,0 0.177 2 1.771 7 squares and the preferred diameters d are scaled in 5,00 50,0 0.196 9 1.968 5 accordance with the R20 series of preferred numbers; the 5,60 56,0 0.220 5 2.204 7 limits of the diameter steps are the intermediate values of the R40 series of preferred numbers. 6,30 63,0 0.248 0 2.480 3 7,10 71,0 0.279 5 2.795 3 In the inch tables, the values a and d are exact conve