---
title: Donaldson Hy-Pro Lube & Hydraulic Filtration Industry Blog | hydraulic fluid
description: hydraulic fluid | Learn about hydraulic fluid, lube oil, diesel fuel and industrial fluid contamination, filtration and conditioning on the Donaldson Hy-Pro blog.
---

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###### 1 min read

### [Hy-Pro's Product Spotlight: Compact Offline Filter (COF)](https://www.hyprofiltration.com/blog/productspotlight-cof)

 By [Hy-Pro Marketing](https://www.hyprofiltration.com/blog/author/hy-pro-marketing) on Thu, Apr. 01, 2021

# Hy-Pro's Compact Offline Filter

Our newest and smallest unit yet, the Compact Offline Filter is able[![COF_Group-2](https://www.hyprofiltration.com/hs-fs/hubfs/COF_Group-2.jpg?width=201&name=COF_Group-2.jpg)](https://www.hyprofiltration.com/products/fluid-conditioning-equipment/offline-filter-system/cof-overview-0) to fit where no other filtration equipment can. Ideal for smaller systems or where a larger offline system wouldn't fit, this solution can be permanently installed or made portable for ease of use. 

###### Topics: [hydraulic fluid](https://www.hyprofiltration.com/blog/topic/hydraulic-fluid) [contamination](https://www.hyprofiltration.com/blog/topic/contamination) [dirt](https://www.hyprofiltration.com/blog/topic/dirt) [Water Contamination](https://www.hyprofiltration.com/blog/topic/water-contamination) [hydraulic filters](https://www.hyprofiltration.com/blog/topic/hydraulic-filters) [hydraulic and lubrication filter types](https://www.hyprofiltration.com/blog/topic/hydraulic-and-lubrication-filter-types) [Gearbox filtration](https://www.hyprofiltration.com/blog/topic/gearbox-filtration) [new oil](https://www.hyprofiltration.com/blog/topic/new-oil) [micro-dieseling](https://www.hyprofiltration.com/blog/topic/micro-dieseling) [fluid samples](https://www.hyprofiltration.com/blog/topic/fluid-samples) [filtration](https://www.hyprofiltration.com/blog/topic/filtration) [oil analysis](https://www.hyprofiltration.com/blog/topic/oil-analysis) [hydraulic pump](https://www.hyprofiltration.com/blog/topic/hydraulic-pump) [filters](https://www.hyprofiltration.com/blog/topic/filters) [hydraulic valve](https://www.hyprofiltration.com/blog/topic/hydraulic-valve) [FSL](https://www.hyprofiltration.com/blog/topic/fsl) [liquid conditioning station](https://www.hyprofiltration.com/blog/topic/liquid-conditioning-station) [duplex low-pressure](https://www.hyprofiltration.com/blog/topic/duplex-low-pressure) [oxidation](https://www.hyprofiltration.com/blog/topic/oxidation) [Noria](https://www.hyprofiltration.com/blog/topic/noria) [NSD](https://www.hyprofiltration.com/blog/topic/nsd) [hydraulic](https://www.hyprofiltration.com/blog/topic/hydraulic) [cellulose media](https://www.hyprofiltration.com/blog/topic/cellulose-media) [compressor](https://www.hyprofiltration.com/blog/topic/compressor) [Reliable Plant](https://www.hyprofiltration.com/blog/topic/reliable-plant) [filter comparison](https://www.hyprofiltration.com/blog/topic/filter-comparison) [lube oil](https://www.hyprofiltration.com/blog/topic/lube-oil) [aluminum refinery](https://www.hyprofiltration.com/blog/topic/aluminum-refinery) [conditioning](https://www.hyprofiltration.com/blog/topic/conditioning) [turbine oil](https://www.hyprofiltration.com/blog/topic/turbine-oil) [glass media](https://www.hyprofiltration.com/blog/topic/glass-media)

###### 4 min read

### [Fluid Life Extension](https://www.hyprofiltration.com/blog/fluid-life-extension)

 By [Hy-Pro Marketing](https://www.hyprofiltration.com/blog/author/hy-pro-marketing) on Thu, Mar. 11, 2021

# Extending Fluid Life Saves Money and Helps the Environment

Our mission is to make our customers as efficient as possible, and we achieve that with the highest quality filtration products and total system cleanliness strategies to maximize uptime, productivity and prevent costly fluid contamination related failures. Been there. Done that. Going to do it again tomorrow. But that's not the only way we make our customers efficient. Extending the useful life of in-service fluids pays big dividends in reliability, saves money on premature fluid replacement costs, and reduces the environmental impact of industry by reducing the amount of fluids used and discarded. Enhancing reliability, saving money, and protecting the environment are not only good business, they're our responsibility. To help reduce oil usage, let's first understand why fluids are condemned and prematurely replaced. 

###### Topics: [varnish in hydraulic oil](https://www.hyprofiltration.com/blog/topic/varnish-in-hydraulic-oil) [hydraulic fluid](https://www.hyprofiltration.com/blog/topic/hydraulic-fluid) [dirt](https://www.hyprofiltration.com/blog/topic/dirt) [vacuum dehydration](https://www.hyprofiltration.com/blog/topic/vacuum-dehydration) [filter housing sizing](https://www.hyprofiltration.com/blog/topic/filter-housing-sizing) [oil darkening](https://www.hyprofiltration.com/blog/topic/oil-darkening) [mining](https://www.hyprofiltration.com/blog/topic/mining) [fluid samples](https://www.hyprofiltration.com/blog/topic/fluid-samples) [oil analysis](https://www.hyprofiltration.com/blog/topic/oil-analysis) [filter performance](https://www.hyprofiltration.com/blog/topic/filter-performance) [paper mill](https://www.hyprofiltration.com/blog/topic/paper-mill) [fluid transfer](https://www.hyprofiltration.com/blog/topic/fluid-transfer) [filters](https://www.hyprofiltration.com/blog/topic/filters) [filter cart](https://www.hyprofiltration.com/blog/topic/filter-cart) [gearbox](https://www.hyprofiltration.com/blog/topic/gearbox) [LCS](https://www.hyprofiltration.com/blog/topic/lcs) [duplex high-pressure](https://www.hyprofiltration.com/blog/topic/duplex-high-pressure) [indianapolis](https://www.hyprofiltration.com/blog/topic/indianapolis) [filter elements](https://www.hyprofiltration.com/blog/topic/filter-elements) [lube oil](https://www.hyprofiltration.com/blog/topic/lube-oil) [turbine oil](https://www.hyprofiltration.com/blog/topic/turbine-oil) [desiccant](https://www.hyprofiltration.com/blog/topic/desiccant) [demulsibility](https://www.hyprofiltration.com/blog/topic/demulsibility)

###### 3 min read

### [Understanding ISO Codes](https://www.hyprofiltration.com/blog/understanding-iso-codes)

 By [Hy-Pro Marketing](https://www.hyprofiltration.com/blog/author/hy-pro-marketing) on Thu, Feb. 25, 2021

# ISO Cleanliness Codes Explained

The ISO Cleanliness Code (per ISO4406-1999) is used to quantify particulate contamination levels per milliliter of fluid at 3 sizes - 4µ, 6µ, and 14µ. It is expressed in 3 numbers (example 19/17/14) where each number represents a contaminant level code for the correlating particle size. The code includes all particles of the specified size and larger. For a detailed breakdown and a handy ISO code cheat sheet, see our [ISO Code Guide & Cheat Sheet](https://www.hyprofiltration.com/blog/iso-4406-cleanliness-codes)![Example of an ISO cleanliness code showing particle counts in hydraulic fluid at 4, 6, and 14 micron sizes.](https://www.hyprofiltration.com/hs-fs/hubfs/Screen%20Shot%202021-02-23%20at%202.50.37%20PM.png?width=283&name=Screen%20Shot%202021-02-23%20at%202.50.37%20PM.png)It is important to note that each time a code increases, the quantity range of particles is doubling. Inversely, as a code decreases by one the contaminant level is cut in half. 

###### Topics: [hydraulic fluid](https://www.hyprofiltration.com/blog/topic/hydraulic-fluid) [dirt](https://www.hyprofiltration.com/blog/topic/dirt) [hydraulic filters](https://www.hyprofiltration.com/blog/topic/hydraulic-filters) [Gearbox filtration](https://www.hyprofiltration.com/blog/topic/gearbox-filtration) [vacuum dehydration](https://www.hyprofiltration.com/blog/topic/vacuum-dehydration) [filter housing sizing](https://www.hyprofiltration.com/blog/topic/filter-housing-sizing) [plastic injection molding manufacturer](https://www.hyprofiltration.com/blog/topic/plastic-injection-molding-manufacturer) [oil darkening](https://www.hyprofiltration.com/blog/topic/oil-darkening) [mining](https://www.hyprofiltration.com/blog/topic/mining) [fluid samples](https://www.hyprofiltration.com/blog/topic/fluid-samples) [total systems cleanliness](https://www.hyprofiltration.com/blog/topic/total-systems-cleanliness) [metal analysis](https://www.hyprofiltration.com/blog/topic/metal-analysis) [filter performance](https://www.hyprofiltration.com/blog/topic/filter-performance) [paper mill](https://www.hyprofiltration.com/blog/topic/paper-mill) [fluid transfer](https://www.hyprofiltration.com/blog/topic/fluid-transfer) [filters](https://www.hyprofiltration.com/blog/topic/filters) [hydraulic valve](https://www.hyprofiltration.com/blog/topic/hydraulic-valve) [coalesce technology](https://www.hyprofiltration.com/blog/topic/coalesce-technology) [filter cart](https://www.hyprofiltration.com/blog/topic/filter-cart) [cleanliness](https://www.hyprofiltration.com/blog/topic/cleanliness) [COD](https://www.hyprofiltration.com/blog/topic/cod) [hydraulic oil](https://www.hyprofiltration.com/blog/topic/hydraulic-oil) [gearbox](https://www.hyprofiltration.com/blog/topic/gearbox) [duplex high-pressure](https://www.hyprofiltration.com/blog/topic/duplex-high-pressure) [compressor](https://www.hyprofiltration.com/blog/topic/compressor) [filter elements](https://www.hyprofiltration.com/blog/topic/filter-elements) [lube oil](https://www.hyprofiltration.com/blog/topic/lube-oil) [turbine oil](https://www.hyprofiltration.com/blog/topic/turbine-oil) [desiccant](https://www.hyprofiltration.com/blog/topic/desiccant) [demulsibility](https://www.hyprofiltration.com/blog/topic/demulsibility)

###### 4 min read

### [Industrial Fluid Filtration Best Practices](https://www.hyprofiltration.com/blog/bid/336302/questions-you-need-to-ask-about-fluid-filtration)

 By [Jennifer Yeadon](https://www.hyprofiltration.com/blog/author/jennifer-yeadon) on Thu, Aug. 09, 2018

[![](https://www.hyprofiltration.com/hubfs/question-mark-2123967_1920-1.jpeg) ](https://www.hyprofiltration.com/blog/bid/336302/questions-you-need-to-ask-about-fluid-filtration)

The world of industrial fluid filtration can get a little...murky. Whether it's a lack of information or just simply not knowing, there are many concepts that may not be clear to someone just entering the industry. That's why we're here -- fluid filtration experts that can guide you through any issue you have. To shed some light and educate, here are some frequently asked questions and their answers. 

###### Topics: [hydraulic fluid](https://www.hyprofiltration.com/blog/topic/hydraulic-fluid) [fluid filtration](https://www.hyprofiltration.com/blog/topic/fluid-filtration)

###### 3 min read

### [When a Pump Fails, the Whole System Fails: Hydraulic Pump Reliability](https://www.hyprofiltration.com/blog/hydraulic-pump-reliability)

 By [Hy-Pro Marketing](https://www.hyprofiltration.com/blog/author/hy-pro-marketing) on Tue, Feb. 21, 2017

[![](https://www.hyprofiltration.com/hubfs/images/Hydraulic-Pump.jpg) ](https://www.hyprofiltration.com/blog/hydraulic-pump-reliability)

## The Problem: Hydraulic Pump Failure 

## <https://www.hyprofiltration.com/fluid-transfer-cleanliness-application>

Pumps are the heart of hydraulic systems. When the pump fails, the entire system is down until the pump is operational again. This poses a serious threat to any operation relying on hydraulic systems for productivity.

Recently, a hydraulic valve manufacturer was losing 25 pumps a year on their centralized hydraulic system at a cost of $2,440 each -- and that’s only the pump cost. When you account for maintenance resources, lost oil and lost production, each failure costs ~$25,320.

###### Topics: [hydraulic fluid](https://www.hyprofiltration.com/blog/topic/hydraulic-fluid) [ISO 4406](https://www.hyprofiltration.com/blog/topic/iso-4406) [breathers](https://www.hyprofiltration.com/blog/topic/breathers) [case study](https://www.hyprofiltration.com/blog/topic/case-study) [hydraulic pump](https://www.hyprofiltration.com/blog/topic/hydraulic-pump)

###### 1 min read

### [Filter Sizing: Calculating Clean Element Delta P](https://www.hyprofiltration.com/blog/bid/358065/filter-sizing-calculating-clean-element-dp)

 By [Hy-Pro Marketing](https://www.hyprofiltration.com/blog/author/hy-pro-marketing) on Wed, Nov. 19, 2014

[![](https://www.hyprofiltration.com/hs-fs/file-2655851405-jpg/images/clean_element_dp1.jpg) ](https://www.hyprofiltration.com/blog/bid/358065/filter-sizing-calculating-clean-element-dp)

Choosing the best filter element size and media for a specific application can be tricky. You want media that is tight enough to help you reach your target ISO code. However, if you choose a media that is too tight for your application, the element differential pressure (Delta P or ΔP) will rise too quickly and you will be replacing elements far too frequently.

###### Topics: [hydraulic fluid](https://www.hyprofiltration.com/blog/topic/hydraulic-fluid) [filter sizing](https://www.hyprofiltration.com/blog/topic/filter-sizing) [filter elements](https://www.hyprofiltration.com/blog/topic/filter-elements)

###### 3 min read

### [[Video] Water Contamination and Removal Methods](https://www.hyprofiltration.com/blog/bid/347342/video-water-contamination-and-removal-methods)

 By [Scott Howard](https://www.hyprofiltration.com/blog/author/scott-howard) on Mon, Jun. 02, 2014

 

 Do you know what the 3 different types of water contamination are? What about the 4 methods to remove water from your fluid? Watch our short video for a thorough explanation of each.

###### Topics: [hydraulic fluid](https://www.hyprofiltration.com/blog/topic/hydraulic-fluid) [water](https://www.hyprofiltration.com/blog/topic/water) [vacuum dehydrator](https://www.hyprofiltration.com/blog/topic/vacuum-dehydrator) [coalesce technology](https://www.hyprofiltration.com/blog/topic/coalesce-technology) [headspace dryer](https://www.hyprofiltration.com/blog/topic/headspace-dryer) [video](https://www.hyprofiltration.com/blog/topic/video) [contaminination](https://www.hyprofiltration.com/blog/topic/contaminination) [filter elements](https://www.hyprofiltration.com/blog/topic/filter-elements)

###### 4 min read

### [Glass or Cellulose Filter Media?](https://www.hyprofiltration.com/blog/bid/222084/glass-or-cellulose-which-hydraulic-filter-media-is-best)

 By [Hy-Pro Marketing](https://www.hyprofiltration.com/blog/author/hy-pro-marketing) on Mon, Sep. 17, 2012

# Glass or Cellulose: Which Hydraulic Filter Media is Best?

There are several distinct differences between glass and cellulose media. Media selection should be based on the required cleanliness and other unique needs of the system. Evaluate the Beta ratio (efficiency), dirt holding capacity, flow versus pressure drop characteristics, etc. A [hydraulic filter supplier](https://www.hyprofiltration.com/products/filter-element-upgrade/) should be able to supply more detailed test information in addition to what is supplied in the literature.

## Cellulose vs. Glass: Absolute and Nominal Filter Efficiency

Normally, wire mesh and cellulose media elements are nominally rated, which means they might be only 50% efficient at the rated micron size. Most glass media elements are considered to be “absolute” rated which means that they are 99.5% efficient at the rated micron size. Check the Beta ratio before selecting the media as all “10 micron” filter elements do not filter with the same efficiency. Glass media has superior fluid compatibility versus cellulose with hydraulic fluids, synthetics, solvents and high water-based fluids. 

Elements of different media with the same “micron rating” can have substantially different filtration efficiency. The graphic below provides a visual representation of the difference between absolute and nominal filter efficiency.

[![cellulose filter media and glass filter media ](https://www.hyprofiltration.com/hs-fs/hubfs/Cellulose-to-Glass-Upgrades-125919-edited.jpg?width=496&name=Cellulose-to-Glass-Upgrades-125919-edited.jpg "cellulose filter media and glass filter media ")](https://www.hyprofiltration.com/hubfs/Cellulose-to-Glass-Upgrades.jpg)

The illustrated glass element would typically deliver an [ISO Fluid Cleanliness Code](https://www.hyprofiltration.com/blog/bid/216397/iso-4406-what-do-those-numbers-mean-in-the-iso-cleanliness-codes) of 18/15/8 to 15/13/9 or better depending upon the system conditions and ingression rate. The cellulose element would typically achieve a code no better than 22/20/17.

## Cellulose vs. Glass: Fibers and Cleaning 

Runaway contamination levels at 4μ[c] and 6μ[c] are very common when cellulose media is applied where a high population of fine particles exponentially generate more particles in a chain reaction of internally generated contaminate.

Inorganic glass fibers are much more uniform in diameter and are smaller than cellulose fibers. Organic cellulose fibers can be unpredictable in size and effective useful life. Smaller fiber size means more fibers and more void volume space to capture and retain contaminate. 

###### Topics: [hydraulic fluid](https://www.hyprofiltration.com/blog/topic/hydraulic-fluid) [ISO 16889](https://www.hyprofiltration.com/blog/topic/iso-16889) [cellulose media](https://www.hyprofiltration.com/blog/topic/cellulose-media) [filter elements](https://www.hyprofiltration.com/blog/topic/filter-elements) [filter comparison](https://www.hyprofiltration.com/blog/topic/filter-comparison) [glass media](https://www.hyprofiltration.com/blog/topic/glass-media)

###### 2 min read

### [Oil Vacuum Dehydrators: Managing Water in Rolling Mill Lubricating Oil](https://www.hyprofiltration.com/blog/bid/213933/oil-vacuum-dehydrators-water-in-rolling-mill-lubricating-oil)

 By [Hy-Pro Marketing](https://www.hyprofiltration.com/blog/author/hy-pro-marketing) on Fri, Aug. 31, 2012

[![](https://www.hyprofiltration.com/hs-fs/file-18425453-png/images/appearanceofwater.png) ](https://www.hyprofiltration.com/blog/bid/213933/oil-vacuum-dehydrators-water-in-rolling-mill-lubricating-oil)

In our last post, [Improving Rolling Mill Oil with Vacuum Dehydration](https://info.hyprofiltration.com/blog/bid/203307/Vacuum-Dehydration-and-Rolling-Mill-Oil), we discussed how the  demulsibility  (ability of the oil to separate from water) of oil is an important characteristic that greatly influences the effectiveness of the lubricant and how a loss of  demulsibility  can result in poorly lubricated bearings, unplanned  downtime  and premature fluid replacement. 

###### Topics: [hydraulic fluid](https://www.hyprofiltration.com/blog/topic/hydraulic-fluid) [contamination](https://www.hyprofiltration.com/blog/topic/contamination) [water](https://www.hyprofiltration.com/blog/topic/water) [Water Contamination](https://www.hyprofiltration.com/blog/topic/water-contamination) [rolling mill lubricating oil](https://www.hyprofiltration.com/blog/topic/rolling-mill-lubricating-oil) [vacuum dehydrator](https://www.hyprofiltration.com/blog/topic/vacuum-dehydrator) [VUD](https://www.hyprofiltration.com/blog/topic/vud)

###### 2 min read

### [Improving Rolling Mill Lubricant Oil with Vacuum Dehydration](https://www.hyprofiltration.com/blog/bid/203307/vacuum-dehydration-and-rolling-mill-oil)

 By [Hy-Pro Marketing](https://www.hyprofiltration.com/blog/author/hy-pro-marketing) on Tue, Aug. 07, 2012

[![](https://www.hyprofiltration.com/hubfs/Harmful%20Effects%20of%20Water%20in%20Oil.png) ](https://www.hyprofiltration.com/blog/bid/203307/vacuum-dehydration-and-rolling-mill-oil)

# Benefits of Vacuum Dehydration for Rolling Mill Lubricant Oil

[Steel mills](https://www.hyprofiltration.com/industry-applications/steel-mill-lubrication-hydraulics/) typically use lubricants with high  demulsibility  for rolling mill  back-up  roller bearings and chocks since relatively high levels of water contaminate the oil from quenching and descaling processes. These rolling mill lubricant oils may be known as Morgoil as they are commonly used on Morgan rolling mill systems.

###### Topics: [hydraulic fluid](https://www.hyprofiltration.com/blog/topic/hydraulic-fluid) [rolling mill lubricating oil](https://www.hyprofiltration.com/blog/topic/rolling-mill-lubricating-oil) [vacuum dehydrator](https://www.hyprofiltration.com/blog/topic/vacuum-dehydrator) [VUD](https://www.hyprofiltration.com/blog/topic/vud)

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