09/30202711 DC : 0

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Test facility
  4.1 General
  4.2 Test tube lengths
  4.3 Test tube sizes
      4.3.1 Steel test tubes
      4.3.2 Copper test tubes
  4.4 Pressure tappings
  4.5 Measurement devices
  4.6 Test fluid
5 Test procedure
  5.1 Test conditions
      5.1.1 Permissible measurement fluctuations
      5.1.2 Steady conditions
      5.1.3 Permissible non-steady conditions
  5.2 Pressure loss in test tubes
  5.3 Valve test
6 Calculation
  6.1 Valve pressure loss determination
  6.2 Coefficient calculations
      6.2.1 Flow coefficient, K[v]
      6.2.2 Flow coefficient, C[v]
      6.2.3 Flow resistance coefficient zeta
  6.3 Uncertainty
      6.3.1 Total measurement uncertainty
      6.3.2 Flow coefficients, K[v] and C[v]
      6.3.3 Pressure loss coefficient, zeta
7 Test report
Annex A (informative) - Lower zeta limit considerations
Annex B (informative) - Flow rate and physical phenomena
        of flow through a valve
  B.1 General
  B.2 Normal flow conditions
  B.3 Cavitation
  B.4 Flashing (self-vaporizations)
Annex C (informative) - Uncertainty on measurement
  C.1 Introduction
  C.2 Permissible measurement fluctuations
      C.2.1 General
      C.2.2 Direct visual observation of signals
            delivered by the systems
      C.2.3 Automatic recording of signals delivered
            by measurement systems
      C.2.4 Automatic integration of signals
            delivered by the measurement systems
  C.3 Measured value stability on physical quantities
  C.4 Determining flow rate and pressure loss
      coefficients in turbulent rating condition
Bibliography

BS EN 1267