EN 60609-2:1999

Foreword
Introduction
1 General
  1.1 Scope and object
  1.2 Excluded topics
  1.3 Normative reference
2 Terms, symbols and definitions
  2.1 Units
  2.2 List of terms
  2.3 Location and type of damage to Pelton buckets
3 Nature and extent of cavitation pitting guarantees
  3.1 Period of guarantee
  3.2 Definition of the amount of cavitation pitting
  3.3 Operating ranges and duration of operation
      3.3.1 Reference duration of operation
      3.3.2 Actual duration of operation
      3.3.3 Special conditions
4 Test procedure
  4.1 Cavitation pitting repair during the guarantee
      period
  4.2 Measurement and calculation of the amount of
      cavitation pitting
5 Computation of results
  5.1 Fulfilment of the guarantee
Annex A (normative) Examples of amounts of cavitation
                      pittings
Annex B (informative) Bibliography
Annex ZA (normative) Normative references to international
                      publications with their corresponding
                      European publications

This standard serves as a basis for the formulation of guarantees on cavitation pitting on Pelton turbine runners. It also provides a basis for the measurement and evaluation of the amount of cavitation pitting on Pelton turbine runners of a given turbine, which is defined in the contract by power, specific hydraulic energy of machine (head), rotational speed, material, operation etc. Guarantees which restrict the extent of caviation pitting and drop erosion on Pelton turbies at the end of an operating period specified in the contract are necessary when the pitting is expected in all or in some operating ranges.