BS ISO 23309:2020 pdf download.Hydraulic fluid power systems一Assembled systems一Methods of cleaning lines by flushing.
This document specifies the procedures for flushing particulate contamination from the hydraulic lines
and components of hydraulic fluid power systems which is:
— residual in the components after manufacture;
— introduced into the system during the assembly of a new system; or
— introduced into the system after system failure, maintenance or modification of an existing system. The aim of flushing the system is to quickly remove this contamination to reduce the amount of wear and damage that results if these particles are allowed to circulate around the system.
This document is not applicable to:
— the chemical cleaning and pickling of hydraulic tubes;
— the cleaning of major system components (this is covered in ISO/TR 10949).
2 Normative references
The following documents arc referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 4021, Hydraulic fluid power — Particulate contamination analysis — Extraction offluid samples from lines of an operating system
ISO 4406, Hydraulic fluid power — Fluids — Met hod for coding the level of contamination by solid particles
ISO 4407, Hydraulic fluid power — Fluid contamination — Determination of particulate contamination by the counting method using an optical microscope
ISO 5598, Fluid power systems and components — Vocabulary
ISO/TR 10949, Hydraulic fluid power — Component cleanliness — Guidelines for achieving and controlling cleanliness of components from manufacture to installation
ISO 12669, Hydraulic fluid power — Met hod for determining the required cleanliness level (RCL) of a system
ISO 16431, Hydraulic fluid power — System clean-up procedures and verification of cleanliness of assembled systems
ISO 16889, Hydraulic fluid power — Filters — Multi-pass method for evaluating filtration performance of a filter element
ISO 18413, Hydraulic fluid power — Cleanliness of components — Inspection document and principles related to contaminant extraction and analysis, and data reporting
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 5598 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:J/wwwiso.org/obp
— I EC Electropedia: available at http://www.electropedia.org/
3.1 Flushing
process of cleaning a hydraulic piping system that involves the circulation of turbulent hydraulic fluid at high velocities within the piping system loops to remove, transport and filter out particles that have been introduced into the system during manufacture, building, maintenance, or after repairs
3.2 Flushing level
the cleanliness level to be achieved after flushing (3J) which shall be cleaner than the required cleanliness level (RCL)(3.3)
Note 1 to entry: A cleanliness level of one ISO code cleaner than the RCL (13) is suitable (see ISO 4406).
3.3 required cleanliness level RCL liquid cleanliness level specified for a system or process
Note I to entry: Sec ISO 16431.
3.4 Reynolds number Re dimensionless ratio of the internal flow forces to the viscous forces within a fluid which is an indicator
of the flow characteristics (laminar or turbulent) of a moving fluid
4 Principle of flushing
The purpose of flushing is to quickly remove surface particulate contamination to both limit the amount of damage to the components and to quickly achieve the RCL by the customer. This is achieved by circulating clean fluid under conditions of high fluid velocity, temperature and turbulence that are higher than that experienced in normal service and that will pick up the particles from the surfaces and transport them to a clean-up or flushing filter.
The RCL is usually specified by the customer, but for the case where the RCL is not stated, Annex A provides selection guidelines. Component suppliers shall be able to specify the cleanliness level of their components. ISO/TR 10949 and ISO 18413 specify methods of evaluating and documenting the cleanliness level.BS ISO 23309 pdf download.