Reaffirmed 2023

NATIONAL FOREWORD

This Indian Standard which is identical with ISO/TR 17766 : 2005 ‘Centrifugal pumps handling viscous liquids - Performance corrections’ issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on recommendation of the Pumps Sectional Committee and approval of the Mechanical Engineering Division Council.

This Indian Standard gives performance corrections for all designs of centrifugal and vertical pumps of conventional design, in the normal operating range, with open or closed impellers, single or double suction, pumping Newtonian fluids are included.

The performance of a rotodynamic (centrifugal or vertical) pump on a viscous liquid differs from the performance on water, which is the basis for most published curves. Head (H) and rate of flow (Q) will normally decrease as viscosity increases. Power (P) will increase, as will net positive suction head required (NPSHR) in most circumstances and starting torque may also be affected. Methods of energy loss analysis and determination of correction factor are given in this Standard.

When a liquid of high viscosity, such as heavy oil, is pumped by a rotodynamic pump, the performance is changed in comparison to performance with water, due to increased losses. The reduction in performance on viscous liquids may be estimated by applying correction factors for head, rate of flow, and efficiency to the performance with water.

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

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

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