Knowing how to choose the most suitable filter for use on your machines is essential in order to preserve the good condition of the hydraulic and fuel systems, removing contaminants. However, the performance of liquid filters often raises doubts about its evaluation and comparison criteria. Part of this uncertainty comes from the fact that many people choose a filter only for the nominal reason, whose values are arbitrary, being provided by the manufacturer.
In order to help you clear some of your doubts, we will discuss in today’s post about the beta reason for filters. This is one of the best methodologies for comparing filter performance, carried out according to standard procedures in the industry. Its application allows measuring the capacity of the filter to remove particles of a given size in the fluid stream, evaluating its efficiency.
What is the beta ratio of filters
The beta ratio of filters consists of a more complete and accurate type of testing compared to other forms of classification most used. The main one is the nominal ratio, which indicates the size of the contaminant that the filter is capable of removing, according to its manufacturer. This method, however, is insufficient for comparison, as it varies according to each manufacturer. For example, two filters of the same nominal rating from two different manufacturers may not have the same performance.
Another common method is the efficiency of filter removal, which measures the percentage of particles removed in the fluid by the filter. However, this assessment criterion may also not be the most appropriate. Often, the parameter used is the weight of the contaminant removed, which does not represent the size of the particle capable of passing through the filter.
In this sense, the beta ratio of filters gains special importance as a performance and comparison parameter. This index is determined by counting particles of a specific size that enter the filter, dividing them by the number of particles of the same size that leave the filter. For example, a filter where 20 thousand particles enter and one thousand come out, has a beta (ß) ratio of 20 (that is, the result of 20 thousand divided by one thousand).
To convert this result into a number that shows efficiency, just apply the following formula:
x = 100*[(ß -1)/ß]
Thus, in the example seen above, where the beta ratio is 20, the filter would have a 95% efficiency for removing particles of a specific size. Let’s see:
x = 100* [(20-1/20)
x = 100* (19/20)
x = 100* (0,95)
x = 95%
Some efficiency values are very common; therefore, we can present them in a table for eventual consultations. Check out some of them below:
(x = particle size in microns)
ßx = 2
ßx = 10
ßx = 20
ßx = 75
ßx = 200
ßx = 1.000
The beta ratio of filters is the best rating
Some precautions are necessary in order to adopt the beta ratio of filters for comparison, since it does not consider factors of operating condition, such as changes in temperature and pressure. However, there is no doubt that it is one of the best ways to measure the expected performance of a filter and choose the most suitable for each machine.
In addition, predictive maintenance procedures such asfiltration and microfiltration they are excellent tools for the purpose of evaluating the removal capacity and performance of your equipment. These techniques act in the extraction of solid contaminants from the fluids, prolonging the useful life of the equipment and contributing to cost reduction. Improving the efficiency of retention, they improve the functioning of the equipment and reduce the risk of corrective maintenance.
Do you still have questions about beta filtering, predictive maintenance or filtering? Always count on POC Filters to clarify them and, from there, make the best decisions for the success of your business. Contact with our team of experts or make a free consultation now!