BS ISO 23309:2020

What is ISO 23309 about?  

ISO 23309 discusses hydraulic fluid power systems. A hydraulic fluid power system has a pump driven by a prime mover (such as an electric motor or internal combustion engine) that converts mechanical energy into fluid energy. ISO 23309 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 
• Introduced into the system after a 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 

Note: ISO 23309 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) 

Who is ISO 23309 for? 

ISO 23309 on hydraulic fluid power systems is useful for: 

• Hydraulic power plants 
• Design engineers 
• Quality control personnel 
• Research and development facilities 

Why should you use ISO 23309?  

In hydraulic fluid power systems, power is transmitted and controlled through a liquid under pressure within an enclosed circuit. The initial cleanliness level of a hydraulic system can affect its performance and useful life. Unless removed, particulate contamination present after manufacturing, assembly, component failure and repair of a system can circulate through the system and cause damage to the system components. To reduce the probability of such damage, the fluid and the internal surfaces of the hydraulic fluid power system need to be flushed clean to a specified level which is possible by using ISO 23309. 

ISO 23309 states that Flushing of lines in a hydraulic system needs to be viewed as one means of removing in-built and residual contamination and should not be the sole method for cleaning such systems unless other methods are impractical. Therefore, using ISO 23309 you can specify the procedures for flushing particulate contamination from the hydraulic lines and components. 

What’s changed since the last update?  

BS ISO 23309:2020 supersedes BS ISO 23309:2007. BS ISO 23309:2020 includes some technical changes with respect to BS ISO 23309:2007. These include: 

• Identifies the shortfall of the Reynolds formula when it's used in isolation 
• Identifies the importance of flushing oil velocity, temperature, and viscosity 
• Identifies to the practitioners who perform flushing procedures that if they only consider the Revalue the flushing velocity could be much less than the system oil flow within the system and what it will be subjected to in normal service 
• Raises awareness and importance of the factors other than the Re valve that affect the effectiveness, efficiency, and reliability of any flushing process