What are the classifications of liquid filter bags?
Liquid Filter Bags are Divided Into:
Polypropylene fiber (polypropylene, PP): Polypropylene has good abrasion resistance and high elastic recovery rate. It is an excellent thermoplastic fiber. Polypropylene felt is often used in low-temperature pulse filter bags in melting plants and pulse filter bags in chemical and pharmaceutical factories. middle.
Polypropylene Accuracy Range: 0.1-500 microns, the highest temperature is 94 degrees.
Polyester Fiber (Polyester, PE): Special polyester fiber has good performance at room temperature and is the main filter material in bag filters. It can withstand an operating temperature of 130°C under dry conditions; continuously working above 130°C will harden; fade; become brittle, and the temperature will weaken its strength. Accuracy range: 1–300 microns.
Nylon Mesh (NMO): Nylon mesh, also known as nylon mesh, nylon mesh, nylon mesh, is made of nylon 6 (PA6) monofilament woven by a flexible rapier loom, dyed (if necessary), heat Shaped and processed. It is made of chemical synthetic fibers and belongs to the polyamide series. Nylon wire mesh has high strength, good abrasion resistance, chemical resistance, water resistance, and elasticity. Because the wire diameter is uniform and the surface is smooth, the ink pass ability is also excellent. The disadvantage is that the stretchability of nylon mesh is relatively large. The tension of this kind of screen is reduced for a period of time after the screen is stretched, which makes the screen-printing plate slack and reduces the accuracy. Therefore, it is not suitable for printing circuit boards that require high dimensional accuracy.
PTFE (Polytetrafluoroethylene): Polytetrafluoroethylene is a neutral polymer compound with a unique molecular structure that is completely symmetrical. The special structure makes it have good thermal stability, chemical stability, insulation, lubricity, water resistance, etc. High temperature resistance, wide operating temperature range, can be used continuously at 260°C (long-term continuous use at high temperature, instantaneous temperature can reach 280°C; strong chemical stability, corrosion resistance; good self-lubrication, extremely low friction coefficient, and very small filter wear; PTFE The surface tension of the film is very low, and it has good non-stickiness and water repellency.
The PTFE coated filter material can achieve surface filtration. This is because the PTFE coated filter material has a microporous structure and has no through holes on the surface, so that dust cannot enter the inside of the membrane or the substrate through the surface of the membrane, so that only gas passes through. Keep dust or materials on the surface of the membrane. At present, coated filter materials have been widely used in many fields such as industrial dust removal and precision filtration.
Glass Fiber: Deep filtration, the filter material is composed of multiple layers of glass fiber, suitable for filtering hydraulic oil, lubricating oil, refractory liquid, fuel and synthetic liquid.
Stainless Steel Metal Mesh: Surface filtration, with very low flow resistance.
The Filter Material Adopts Weaving Methods: Interwoven type, twill type and linen type. The metal mesh filter material is suitable for oil suction filters of hydraulic and lubrication systems, or for coarse filtration of high-speed fluids, or for safe filtration of coolants.
According to the Filtration Efficiency of the Liquid Filter Bag, it is Divided Into:
Relative Filtration: Deep filtration is a filtering method that intercepts the surface and inside of the filter layer. The non-woven fibers in the non-woven fabric (also called non-woven fabric) are intertwined randomly, and the large particles are first intercepted in the non-woven fabric. Outside, smaller ones penetrate in, but they are intercepted at a certain depth, and smaller impurities go deeper. Finally, particles smaller than a certain size and a small number of particles larger than this size pass through. Commonly used for deep filtration are polypropylene, polyester, NOMEX, polytetrafluoroethylene and other material filter bags, non-woven fabrics and other filter consumables. The internal structure, material thickness, and fiber surface will all contribute to the interception efficiency of deep filtration. Influence. Usually, this kind of filtration is also called relative filtration, and the filtration accuracy is often defined according to the filtration efficiency of impurities with a certain pore size. Different companies have different test methods for filter bag accuracy and achieved filtration efficiency requirements, some are defined as 80~85%, and some are defined as 50~70%.
Absolute Filtration: Absolute filtration is a filtering method that uses surface interception, 95-99.9% of particles larger than a certain size are intercepted, and all particles smaller than this size pass. The pore size of the surface of the filter bag material must be the same size, the fiber weave must be tight and firm, and the material must be able to withstand greater pressure after the material is joined to prevent leakage and strictly ensure the absolute filtering effect.
