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Tech Tip: New Hydraulic Oil Is Not Clean Hydraulic Oil

Jun 2, 2011 | Hydraulic & Lubrication, ISO Cleanliness, Oil Quality & Purification

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ISO Cleanliness 4406 Code Chart | Precision Filtration Products

ISO Cleanliness Code Chart

Did you ever wonder if new hydraulic oil was really clean?? The truth is… it’s not! Straight from the drum, so-called “new” hydraulic oil has a typical ISO cleanliness level of ISO 4406 23/21/18 or worse. Now that number may not mean a lot to you, but it’s four cleanliness code levels below what is considered acceptable for a high-pressure, high-performance hydraulic system.

Looking at it another way, a 25-GPM pump operating continuously in hydraulic oil at the aforementioned ISO rating (23/21/18) will circulate approximately 3,500 pounds of dirt to the hydraulic system’s components each year. That’s enough to cause some serious wear and tear, and possibly premature malfunctions!

Here’s my advice to everyone out there who operates industrial equipment that filters hydraulic fluid… Make sure to keep your systems running at peak performance – Always filter the oil before filling or topping off your reservoirs. Click on the chart to the left for more information about ISO cleanliness code 4406 and how to achieve your target cleanliness levels.

Do you have a question about filters or filtration? Feel free to contact us anytime. Our friendly team of experts will be happy to help you out with your particular issue.

Until next time!

Paul at PFP  Paul at Precision Filtration Products

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