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Filter selection and application; Principles for filter selection. A filter is a small device used to remove small amounts of solid particles from liquids, thereby ensuring the proper operation of equipment. When fluid enters a filter cartridge equipped with a filter screen of specific specifications, impurities are trapped, while the clean filtrate is discharged from the filter’s outlet. When cleaning is needed, the removable filter cartridge can be taken out, cleaned, and then reinstalled. 1. Filter inlet and outlet diameter: In principle, the diameter of the filter’s inlet and outlet should not be smaller than that of the inlet of the pump it is designed to work with; it is generally the same as the diameter of the inlet pipe. 2. Nominal pressure selection: Determine the pressure rating of the filter based on the highest pressure that may occur in the filtration pipeline. 3. Selection of pore count: The choice of the filter’s pore count is primarily determined by the size of the impurities that need to be filtered out, in accordance with the requirements of the medium processing process. The particle sizes that can be intercepted by screens of various specifications are listed in the table “Screen Specifications”. 4. Filter material: The material of the filter is generally chosen to be the same as that of the process pipeline it is connected to; depending on the operating conditions, filters made of cast iron, carbon steel, low-alloy steel, or stainless steel can be considered. 5. Calculation of filter pressure loss: For water filters, under normal conditions of rated flow rate, the pressure loss is 0.52 to 1.2 kPa. Applications of filters 1. Stainless steel filters: These filters are widely used in pipelines carrying various media such as steam, air, water, and oils. They protect various devices within the pipeline system, including water pumps and valves, from blockages and damage caused by impurities such as rust and weld slag present in the pipes. Stainless steel filters have strong resistance to fouling, are easy to clean, feature a large flow area, low pressure loss, a simple structure, and are small in size and light in weight. The filter screens are all made of stainless steel, offering strong corrosion resistance and a long service life. 2. Y-type filter: A filtering device that is essential in the piping systems used to transport media. Y-type filters are typically installed at the inlet of pressure reducing valves, pressure relief valves, level control valves, or other equipment, in order to remove impurities from the media and thus protect the proper functioning of these valves and equipment. The Y-type filter features an advanced structure, low resistance, and easy sewage discharge. 3. Y-type telescopic rod filter: The Y-type telescopic rod filter features a new design that combines a Y-type filter with a telescopic joint. It has a simple structure and is easy to use; it addresses the issue of difficulties in installing pipes due to differences in the length of flanges on products manufactured to various standards. This type of filter is primarily used in high-rise buildings, multi-story structures, or industrial facilities for water supply and drainage systems. It is usually installed at the inlet end of pressure reducing valves, pressure relief valves, level control valves, or other major equipment. By using this telescopic rod filter, it becomes easier to remove debris from the pipes as well as to install or remove them, thereby ensuring the proper functioning of valves and equipment. 4. Basket filter: A small device that removes a small amount of solids present in liquids, and it helps to ensure the proper operation of compressors, pumps, as well as other equipment and instruments ； It is also a small device used to improve product purity and purify gases. Therefore, basket filters are widely used in industries such as petroleum, chemicals, chemical fibers, pharmaceuticals, and food. A basket filter consists of a housing, a drain cover, a filter element, a filter screen, bolts, and other components. 5. T-type filters: T-type filters are widely used in pipelines carrying various media such as steam, air, water, and oils. They protect various devices in the pipeline system, such as water pumps and valves, from blockages and damage caused by debris like rust and welding slag within the pipes. The T-type filters produced by Shanghai Nimi Valve Manufacturing Co., Ltd. feature strong anti-fouling capabilities, easy waste discharge, a large flow area, low pressure loss, a simple structure, and a compact size ； The filter media of T-type filters are all made of stainless steel, which offers strong corrosion resistance and a long service life ； T-type filters are also divided into straight-flow and cross-flow types; the density of the filter mesh ranges from 10 to 120 mesh, and the operating temperature is 0~450°C, allowing for selection based on the user’s requirements.