Key points
Understanding where and how to install Fluid System Filters properly will help your system function at peak performance.
Unwanted particles and other contaminants are antithetical to a properly functioning industrial fluid system filters. They can interfere with operations downstream, harm crucial components, reduce the quality of end products, and prevent accurate sampling and analysis of the fluid.
In addition, contamination often results in damaged valves and regulators, leading to costly downtime and sometimes requiring fluid system operators to return the components to the manufacturer.
Installing the proper filters in your systems can significantly limit the damage contamination can cause by trapping and containing particulates at crucial points during fluid system operation. If you understand where and when to use gas and liquid filters, it can save time, reduce maintenance costs, and improve the safety of your facility (Figure 1).
Fluid System Filters Can Save Your System
In many common industrial processes, contaminants and particulates are a natural byproduct. Whether they come from mechanical equipment, internal corrosion, or inherently dirty media, contaminants pose real threats to fluid system components, including valves and regulators. In addition, they can compromise your analytical equipment and give you an inaccurate picture of what is going on in your facility.
One of the most common problems caused by unwanted particulates is premature wear and damage when they are trapped between the component’s stem and seat. Once damaged, the component will no longer work as expected.
The resulting problems – whether it is a valve that no longer completely shuts off flow or a pressure reducing regulator that allows higher pressures downstream – mean the fluid system is no longer operating correctly. In such situations, it is likely that operational and safety issues will arise.
Where to Install Fluid System Filters
To prevent unnecessary damage to fluid system components, filters (Figure 2) may be installed at several common locations throughout the system, including near:
- Cylinder gas dispensing. Many process gases arrive in fluid systems in cylinders which must be maintained to function properly. If the cylinder has deteriorated in any way, it is more likely that particles inside the cylinder might flake off into a fluid system when gas is delivered. That is why inserting filters directly downstream from the cylinder is a best practice. If your system is prefabricated, it may already have filters built into the system that can keep contamination away from the system at this vital point in the process.
- Valves and regulators. It is vital for your facilities to protect valves and regulators from contaminant-related damage. Filters should be installed directly upstream from important valves, regulators, or other points of use. These filters will help keep particulates from getting trapped in valves and regulators, which will keep the system functioning properly without interruption.
- Pumps. Over time, debris from industrial pumps – due to their many moving parts – can collect in a fluid system. This debris could do damage to the fluid system, so placing a filter downstream from a pump will prevent contaminants from moving through the process and harming other components.
- Online analysers. Installed at sampling points, online analysers are some of the most sensitive pieces of equipment in a fluid system. Contaminants can not only damage the analysers but can also interfere with accurate sampling by compromising the sample’s integrity.
Though most operators understand how important it is to install a filter prior to the analyser, it is critical to choose the right filter for your specific needs. A poorly chosen filter may miss particulates and lead to dirty samples.
A large filter with too much internal volume can delay the fluid flow through it, compromising the accuracy of any sample taken from that point. A reliable supplier should be able to advise you on which filter will work with your particular analyser.
Different Types of Fluid System Filters
Selecting the proper filter for specific applications is important and should adequately address the needs of your fluid system (Figure 3). Consultation with your filter supplier should help to identify which filter is needed for specific applications. The most common filters include:
- Particulate filters (Figure 4a). These filters are used to remove particulate contaminants and are suitable for general industrial gas and liquid filtration. Here, a filter element simply stops particulates from continuing down the process line.
In-line particulate filters are typically available for welded applications, in which case they are not serviceable, or non-welded applications, in which they can be removed from the system, cleaned, and replaced. Tee-type particulate filters, meanwhile, allow filtering elements to be maintained or replaced without removing the body from the system, creating some maintenance advantages.
- Coalescing filters (Figure 4b). This type of filter is commonly used for online analyser applications and is suitable for gas filtration. Here, the filter element captures fine liquid droplets suspended in the gas, forcing them to coalesce (or form large drops) within the filter element. These drops are forced to the outside of the element by gas flow and gravity; liquid then exits the filter through a drain port.
- High-purity filters (Figure 4c). For applications in which purity must be maintained at all costs, ultrahigh-purity filters are available that can achieve a particle removal rating greater than 99.99% at 0.003 µm at maximum flow rate. These filters are not typically required for general industrial applications and are more commonly found in semiconductor applications.
Not only is choosing the right filter important, but it is also critical to ensure the filter you select can be used with the end connections that are in your system. They must also be constructed of materials that can withstand the stresses of your particular operation.
For example, some fluids may damage common stainless steels. In those instances, a higher grade of stainless steel may be necessary not only in the filters, but also in the rest of the components.
Properly Installing and Maintaining Your Fluid System Filters
Once the proper filter has been chosen, it must be installed correctly to ensure its ongoing performance. Usually, technicians can install filters similarly to tube fittings. Use the flow arrow to guide you in figuring out which specific inlet and outlet ports indicate how fluids should flow through the system. Always adhere to the manufacturer’s published instructions throughout the installation process.
If the filter is being placed near a valve or regulator, make sure the valves are properly mounted to avoid putting excess pressure on the tubes or pipes. Brackets should be used instead and should be robust enough to absorb the torque necessary to remove and replace the filter as necessary. Ideally, filters should be easily seen, accessible, and protected from potential damage.
Finally, filters should be cleaned and maintained regularly to ensure effective operation. Since filters are designed to stop contamination, they will eventually clog. You must then decide whether it is more cost-effective to clean or replace the filter, depending where in the preventive maintenance cycle the problem occurs. Another indication of a dirty filter is a significant drop in downstream pressure.
If the filter needs to be replaced, isolate the filter from its system and stabilise the body with a wrench. Loosen the filter’s bonnet and then remove the dirty or clogged filter and replace it with a new one.
Proper filtration can protect your industrial fluid system from unnecessary downtime, safety concerns, and unexpected costs. Filters can keep your system working well and producing reliable results and high-quality products. Work with a reputable filter supplier to make sure you are choosing the right filters for your applications and keep those systems flowing freely for the long haul.
