NATIONAL FOREWORD

This Indian Standard (First Revision) which is identical with ISO 5167-1 : 2003 ‘Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full Part 1 : General principles and requirements’ issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on the recommendation of the Hydrometry Sectional Committee and approval of the Water Resources Division Council.

This standard was first published in 1999 as identical with ISO 5167-1 : 1991 which covered measurement of fluid flow by orifice plates, nozzles and venture tubes inserted in circular crosssection conduits running full. The first revision of this standard is being done to align it with the latest version of ISO 5167-1 : 2003.

This standard is published in five parts. Other parts in this series are:

Part 2 Orifice Plates

Part 3 Nozzle and Venturi nozzles

Part 4 Venturi tubes

Part 5 Cone meters

The text of ISO Standard has been approved as suitable for publication as an Indian Standard without deviations. Certain 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’; and

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.