ISO 4406 pdf download

ISO 4406 pdf download.Hydraulic fluid power — Fluids — Method for coding the level of contamination by solid particles 1 Scope This International Standard specifies the code to be used in defining the quantity of solid particles in the fluid used in a given hydraulic fluid power system. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 4407:1 991 , Hydraulic fluid power — Fluid contamination — Determination of particulate contamination by the counting method using a microscope. ISO 1 1 1 71 :1 999, Hydraulic fluid power — Calibration of automatic particle counters for liquids. ISO 1 1 500:1 997, Hydraulic fluid power — Determination of particulate contamination by automatic counting using the light extinction principle. 3 Code definition 3.1 General The purpose of this code is to simplify the reporting of particle count data by converting the numbers of particles into broad classes or codes, where an increase in one code is generally a doubling of the contamination level. The original code in accordance with ISO 4406:1 987 stated the reporting at two sizes, W 5 µm and W 1 5 µm, but the sizes in this revision have been changed to account for the use of a different calibration standard for optical automatic particle counters. The reported sizes are W 4 µm(c), W 6 µm(c) and W 1 4 µm(c), the last two of these being equivalent to the 5 µm and 1 5 µm particle sizes obtained using the ISO 4402:1 991 method of calibrating automatic particle counters. ISO 4402:1 991 has been replaced by ISO 1 1 1 71 :1 999. Throughout this International Standard, the use of µm(c) means that particle size measurements are carried out using an automatic particle counter which has been calibrated in accordance with ISO 1 1 1 71 . Measurement of particles using an optical microscope as specified in ISO 4407:1 991 establishes the size of a particle...