Feiliter filters play an important role in many industries from automotive to manufacturing. The right choice of filter helps protect expensive machinery, ensures equipment runs smoothly, and maintains the high quality of your end product. The wrong filter can result in equipment damage, and even entire system failures.
So how do you know your filters are getting the job done right? When it comes to filter performance, two main things to consider are capture efficiency and retention efficiency. Capture efficiency refers to how effectively a filter captures particles while retention efficiency measures how effectively a filter retains those particles. If a filter fails to effectively capture and retain particles, it can inadvertently contaminate and harm fluid systems.
Filter testing can let you know how well your filter is performing, and whether it is time to consider an upgrade. Two types of testing are the industry standard multi-pass test ISO16889 and Dynamic Filter Efficiency (DFE), a multi-pass test designed to quantify capture and retention efficiency of hydraulic and lube filters in real time.
Filter elements are designed to remove impurities and contaminants from your operating system, and ensure that contaminants don’t interfere with the functionality of your machinery. Though their types and purposes can vary greatly, there are common configurations, including cartridge filters and spin-on filters.
Filters are made in a number of materials, sometimes in combination with one another. Let’s take a look at some of the most common types of hydraulic filter media.
Cellulose
Cellulose is a widely abundant organic polymer that’s sourced mainly from wood pulp and cotton, and is relatively inexpensive to produce. However, its lack of uniform pore structure gives it a nominal rating, which can make cellulose filters susceptible to deterioration and shedding. While cellulose can capture particles, it’s less effective in retaining them, which along with shedding can lead to damage in industrial systems.
Glass
Glass media has a uniform pore structure, which gives it the ability to capture and contain more particles than cellulose. It’s not susceptible to structural manipulation, and it is immune from shedding, so that dirt stays where it is. For this reason, glass filters are awarded absolute ratings, and are considered an upgrade to systems that have been running on cellulose filters.
Wire Mesh
Made from stainless steel, wire mesh filter media have absolute ratings, however it is more durable than cellulose, and more capable of containing particulate. Wire mesh filters are ideal for fire-resistant fluid applications, such as high temperature governor controls, steel mill hydraulics and aircraft ground support equipment.
Coalesce
Coalescing filters are designed to separate two fluids from one another in different phases, while also filtering out particulate. Common in a variety of industries, coalescing filters are available in two subtypes: liquid-liquid filters, and liquid-gas filters, Coalescing filters can bring together into large drops free and emulsified water dispersed in oil and fuels. Those large drops can then be easily removed from the oil or fuel stream. Synthetic coalescing media now replace treated paper media for superior reliability.
Resin
Resin filter media treats fluids at a molecular level by removing contaminant molecules such as acids and free radicals, that form as a byproduct of fluid degradation and oxidation. Resin filters are designed to remove specific contaminants from fluids without removing additives, which results in better fluid performance.
Non-spark Discharge
High flowing lubrication systems found in many gas turbines create a static charge that builds up on filter elements until the charge jumps to a ground source. These very high temperature events ( 1000 deg F + ) burn the oil creating varnish which collects in servo valves causing failure. Non-spark filter medias are grounded so they don't build up a static charge, which improves equipment reliability and extends fluid life.
These filters are designed to prevent spark discharge, and therefore prevent oil degradation and antioxidant additive depletion while extending fluid life.
Water Removal
Water removal filter media is designed to remove small amounts of water from hydraulic systems. Water removal filters are typically divided between two types, coalescing and absorption.
Acid and Varnish Removal
Designed to remove the contaminants that accumulate in all lubricants and lubricating fluids, and ensure smoother operating systems.
Upgrading your filters can improve your system, reduce damage to your machinery, and save money, while drastically improving your sustainability efforts. For more information on upgrading your filters, contact Feiliter today.
Filter elements are rated by particular micron sizes, which describes the smallest size of the particles they are able to remove. But filter elements with the same micron rating can have very different efficiencies, depending on the types of media they’re constructed from.
When choosing the proper filter solution, it’s important to understand how different types of media impacts a filter’s performance. Filters are rated by two types of efficiency ratings, nominal and absolute. Nominal ratings refer to a degree of filtration by the weight of solid particles. However, filters rated as nominal efficiency have no maximum pore size, meaning that they can still allow unwanted larger particles to pass through and potentially damage parts of the system. Media with absolute ratings have uniform pore size, and derive their value from the largest size particle that can pass through its pores.
Sourced mainly from wood pulp and cotton, cellulose is a widely used media type for industrial applications. Due to a lack of uniform pore size and effectiveness of organic cellulose fibers, cellulose filters are susceptible to degradation and structural manipulation with increasing fluid temperatures. They are therefore awarded nominal efficiency ratings, since they may allow unwanted particles to pass through and contaminate the system.
On the other hand, inorganic glass media fibers are more uniform in diameter, and smaller than cellulose fibers. That means they are able to capture and retain more particles than cellulose. As a result of their effectiveness and predictability, glass filter elements are given absolute efficiency ratings and are considered a high quality alternative to cellulose.
When upgrading your hydraulic oil filters from cellulose to glass media elements, the cleanliness of the system must be stabilized. During this phase, the life of a glass element may be temporarily shortened as it works to bring ISO cleanliness codes into a target range by removing accumulated fine particles that passed into the system via previous cellulose filters. However, once the system is clean, glass elements may last 4-5 times longer than the cellulose element it replaced.
For more information on how Feiliter can help you upgrade your filters from cellulose to glass, contact us today.
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