NATIONAL FOREWORD

This Indian Standard (Part 2) which is identical with ISO 8636-2 : 2007 ‘Machine tools — Test conditions for bridge-type milling machines — Testing of the accuracy — Part 2: Travelling bridge (gantry-type) machines’ issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on the recommendation of the Machine Tools, Machine Tool Elements and Holding Devices Sectional Committee and approval of the Production and General Engineering Division Council.

In this revision, besides other changes following technical changes have been incorporated:

a) geometrical tests have been rearranged; the new G numbers compared to the old ones are given in the following table:

b) information has been added in ‘‘Object’’ boxes for G6, G12, G13, G14 and G15. This information has been added because the machines have several milling heads and the test items are applicable to all of the milling heads;

c) tolerances on accuracy and repeatability of positioning have been changed in accordance with IS 2063-2 : 2016

d) new test for geometric accuracy of axes of rotation of wrokholding spindles (R1) has been added.

This standard is published in two parts. Other part of this standard is:

Part 1 Fixed bridge (Portal-type) machines

The text of ISO Standard has been approved as suitable for publication as an Indian Standard without deviations. Certain terminology and conventions are, however, not identical to those used in Indian Standards. Attention is particularly drawn to the following:

a) Wherever the words ‘International Standard’ appear referring to this standard, they should be read as ‘Indian Standard’.

b) Comma (,) has been used as a decimal marker while in Indian Standards, the current practice is to use a point (.) as the decimal marker.