For new or rebuilt machines to remove contamination resulting from manufacture, service or overhaul. The fluid system can be contaminated due to dirty assembling elements, corroded surfaces, water, oxidation products and incompatible elastomers such as seals, sealants and coatings. Also, during the assembly process, dirt is ingested and debris is generated due to threading, joining, welding, etc. Put in a can of flusher just before a long trip, and drain the oil immediately after. Refil with new oil and a new filter.

Oil Flushing - Let Oil Analysis Guide Your Decisions Oil Flushing - Let Oil Analysis Guide Your Decisions

Reduce the fluid pH to 5.5 by adding chemical B. Then add Chemical C until 10 percent (volume) is reached. Circulate maximum flow rate for 60 minutes. Control pH and temperature during processing. Figure 1. These samples were taken from a hydraulic system operating in the North Sea. The system had a history of component failures. The top sample was from the reservoir after 15 years of service, before proper cleaning. The bottom sample was after cleaning. The cleaning was performed with the system pressurized and in full service. After the flushing, the system experienced no failures in two years. This is why the final flushing of complex systems often becomes a challenge for management because of increasing costs and delayed completion and recommissioning. Shortcuts often become an easy and sometimes preferred choice. Although such shortcuts can postpone problems, they don’t always solve them. All tubes and hoses should be inspected and blown with highly filtered industrial compressed air. This removes most of the larger particles made by the cutting of tubes and hoses as well as the mounting of fittings.Of course, not everyone is going to do a complete teardown along with a chemical and mechanical cleaning of each component and the system each time a fluid changeover is performed. So let’s examine what should be done at the bare minimum to clean a hydraulic system. Charged Particle (Electrostatic) Separators—Some suppliers have demonstrated success at removing varnish from machine surfaces and stripping out submicron soft contaminants that can contribute to varnish and sludge. This is the fourth and final part in my series on flushing. We’ve already talked about when to flush, the consequences of not flushing, the differences between flushing and oil reclamation, flushing tactics, flushing strategies and flushing sequence. Generally speaking, the required cleanliness level to target during flushing is half the level during normal operation. For example, if the normal operation level is ISO 15/13/11, flush to an ISO14/12/10. Requirements for cleanliness levels of both solid particles and moisture should be achieved.

11 Simple Steps for Flushing a Hydraulic System | Machinery 11 Simple Steps for Flushing a Hydraulic System | Machinery

That said, there are some potential dangers that come with using engine flush and many have claimed engine flush can damage an engine. Oil analyses can be used as often as needed to assess what remains in the circulating fluids. In such cases, the analyses can aid in guiding the process by defining the type and duration of each step in the sequence. Perhaps certain flush steps (tactics) will need to be repeated based on the results of the analysis. Fill the reservoir with pure water. Heat it to 122°F (50°C), up to a maximum of 176°F (80°C). Add Chemical A until it reaches pH 14. By circulating maximum flow rate for 30 minutes, any grease and oil film should have been removed. Control pH and temperature during processing. With a Reynolds number equal to or greater than 4,000, the fluid is certain to have turbulent flow. This is required to remove particles from the surface inside tubes. To also prevent remaining contaminants from becoming suspended during operation, it is required that: Re-flushing number is equal or greater than 1.2 x Re-in service, but always a minimum of 4,000.The following is a list of potential problems (side effects) associated with flushing where oil analysis might provide a timely alert: Cycling Flush Oil Temperature —Using heat exchangers and coolers to change temperature during flushing across a 100 degree F range helps dislodge crusty surface deposits.