EN 62256:2017

FOREWORD
INTRODUCTION
1 Scope
2 Normative references
3 Terms, definitions and nomenclature
4 Reasons for rehabilitating
5 Phases of a rehabilitation project
6 Scheduling, cost analysis and risk analysis
7 Assessment and determination of scope of the work
8 Hydraulic design and performance testing options
9 Specifications
Annex A (informative) - Check-list for evaluation of existing
        turbine
Annex B (informative) - Assessment examples
Annex C (informative) - Checklist for evaluation of related
        equipment
Bibliography

NEW!IEC 62256:2017 is available as IEC 62256:2017 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 62256:2017 covers turbines, storage pumps and pump-turbines of all sizes and of the following types: Francis; Kaplan; propeller; Pelton (turbines only) and bulb turbines.

This document also identifies without detailed discussion, other powerhouse equipment that could affect or be affected by a turbine, storage pump, or pump-turbine rehabilitation. The object of this document is to assist in identifying, evaluating and executing rehabilitation and performance improvement projects for hydraulic turbines, storage pumps and pump-turbines. This document can be used by owners, consultants, and suppliers to define: needs and economics for rehabilitation and performance improvement; scope of work; specifications and evaluation of results. This document is intended to be: an aid in the decision process; an extensive source of information on rehabilitation; an identification of the key milestones in the rehabilitation process; and identification of the points to be addressed in the decision processes. This document is not intended to be a detailed engineering manual nor a maintenance document. This second edition cancels and replaces the first edition published in 2008. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: Tables 2 to 23 modified, completed and moved to Annex A; 7.3.2: subclauses moved with text changes; new subclauses on temperature, noise, galvanic corrosion, galling and replacement of components without assessment; 7.3.3: complete new subclause on residual life; Tables 29 to 32 moved to Annex C; New Annex B with assessment examples.



Key words: Turbines, Storage pump, Pump turbines, Rehabilitation, Performance.