Not that it matters much in relation to flushing...but what what do you mean by petroleum? Do you mean mineral oil as oppose to synthetic?
In any case, the level of flushing depends on a number of things. The main ones being the dirt tolerance of the components in the system and the criticality of the system itself. Then there is the environment that the system is working in.
There is no point in spending lots of time and money flushing a system that will become contaminated during use.
If dirt ingress is likely then the system designer should have used components that are dirt tolerant. In this case flushing would not not normally be required other than to remove large amounts of contaminant created during the pipework installation...swarf and welding bedris etc.
At the other end of the scale there are servo type systems that have dirt sensitive valves and are safety critical. These systems would have to be flushed until the desired level of cleanliness is reached. This would involve flushing blocks in place of the sensitive valves. The valves would only be installed when the system is clean.
When flushing, the oil needs to be turbulent in order to scour the bore of the pipework. It also needs to be hot enough to break up or desolve clusters of debris. To remove dirt from dead spots such as corners and under cuts in manifolds, the direction of the oil needs to be changed. Cylinders need to be looped out because they are very difficult to flush.
Some people use low viscosity flushing oils because they become turbulent more easily. This can be expensive, especially if the flusing oil is not compatible with the system fluid.
The level of flushing and how it is done varies between systems, you will have to decide what is required.
If you can give some more details about the system, we can be a bit more helpful.
Have you looked at ASTM D 4174-89 "Standard Practice for Cleaning, Flushing and Purification of Petroleum Fluid Hydraulic Systems"? This document might contain what you are looking for and is available on line at IHS
hydromech,
Thank you for that input, i will sit down and start look at only what i need.
fieldman
Thanks. I bumped into the ASTM procedure but the site was asking for $. I might draw from my pocket personally, i know my emplyer are not so fun of buying resources.
scary, if your employer won't spend money for the knowledge and standards, will they spend money and time for flushing?
Sounds like time to buy the standards for your own knowledge and make yourself more valuable, then start looking for new job.
Many companies approach is that is faster and easier just to push the green button, start it up, then change what breaks over the next days and weeks.
Unfortunately the cost of information and flushing is directly measureable, the high cost of failure and shortened life is not directly so obvious.
good luck, you're doing the right thing. k
