The selection of the correct strainer requires knowledge of the system and the type of contaminants that must be retained. Strainers are macro filters. They range in particle retention from as large as .500 inch down to 325 mesh (44 microns). Typically we see a range from .250 inches to 200 mesh (74 microns).
The strainer should retain all particles greater than those acceptable to the downstream equipment. Straining too fine may cause operational and maintenance problems due to premature fouling of the straining medium. This can unnecessarily increase the frequency of cleaning and cause flow obstruction to downstream equipment.
The degree of straining is usually decided by the process design engineer. These decisions are usually based upon the engineer's process flow expertise and the recommendations of the manufacturer of the equipment to be protected. The strainer itself is a simple device to operate and, with minimal maintenance, will last for many years.










