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SFB Series Standard Felt Liquid Filter BagsSFB Series Standard Felt Liquid Filter BagsSFB Series Standard Felt Liquid Filter Bags

SFB Series Standard Felt Liquid Filter Bags


SFB Series Standard Felt Liquid Filter Bags are made of high-quality polypropylene, polyester & Nomexfelt materials which provide consistent performance of liquid filtration in various of critical industries. Standard felt liquid filter bags offer efficient depth filtering at increased flow rates, and the glazed outer as well as the plain inner finish are to reduce fiber migration and enhance filtration performance. The collars and top rings of felt liquid filter bags ensure general compatibility with most of commercial bag filter housings in processing. Sewing or welded connection of polypropylene, polyester or Nomex makes the liquid filter bags suitable for different housings and purposes. Felt filter bags extend life time without media migration or bypass. Customized felt liquid filter bags are accepted for different requests in many industrial fields.

Filter Media Polypropylene Felt, Polyester Felt, Nomex Felt
Bag DimensionsSize 1: Ø7"×16.5"
Size 2: Ø7"× 32"
Size 3: Ø4"× 8"
Size 4: Ø4"× 14"
Filtration Rating1, 5, 10, 25, 50, 75, 100, 150, 200, 300μm
Ring StyleGalvanized Steel O-Ring, Plastic Ring, S.S. O-Ring
SeamWelded, Sewing, Welded top & Sewing Bottom, Sewing top & Welded Bottom


● Free silicone construction and wide chemical compatibility

● Ratings of felt filter bags can be made from 1 to 300 micron

● High flow rate and low pressure drop with consistency of performance

● High dirt holding capacity, increasing efficiencies by preventing by-pass

● Glazed finish on polypropylene, polyester & Nomexfelt reduces fiber shedding

● Sewn or fully-welded construction with steel O-rings or molded plastic snap seal rings

● Liquid filter bags are made of 100% FDA approved polypropylene, polyester & Nomexfelt materials

ElectronicsPre RO FiltrationCoatings
Oil RefineryFood & BeveragePaints and Inks
Petrochemical Process  Chemicals & SolventsWaste Water Treatment


Operation Data for Standard Felt Liquid Filter Bags

Filter Media   Polypropylene FeltPolyester FeltNomex Felt
Abrasion & FlexGoodGoodExcellent
Weak Acid ExcellentGoodExcellent
Strong Acid ExcellentGoodExcellent
Weak Alkali ExcellentGoodExcellent
Strong Alkali ExcellentPoorExcellent
Maximum Operating Temperature70℃(160℉)160℃(320℉)250℃(500℉)
Maximum Differential Pressure1.8 bar (26.1 psi)
Recommended Change Out Differential Pressure1.03 bar (15 psi)

Pressure Drop vs  Flow Rate of Standard Felt Liquid Filter Bags


Tech Support


Working Principle of Standard Felt Liquid Filter Bags

● The drawing is the working principle of standard felt liquid filter bags

● Dirty fluid flow through the plain inner finish layer and large particle block in surface

● Felt filter media traps contaminants within its depth, no sliding sideways during processing

● Clean fluid come out from glazed layer, high filtration efficiency and long service life with low cost

Order Information
SFBFilter MediaBag DimensionsFiltration RatingRing StyleSeam

SFB Series 

Standard Felt Liquid Filter Bags

P = Polypropylene Felt1 = Size 1: Ø7"×16.5"1 = 1 μmG = Galvanized Steel O-RingW = Fully Welded
5 = 5 μm
10 = 10 μm
E = Polyester Felt2 = Size 2: Ø7"× 32"25 = 25 μmS = Plastic RingF = Fully Sewing
50 = 50 μm
75 = 75 μm
N = Nomex Felt3 = Size 3: Ø4"× 8"100 = 100 μmQ = Welded Top & Sewing Bottom  
150 = 150 μmU = S.S. O-Ring
4 = Size 4: Ø4"× 14"200 = 200 μmT = Sewing Top & Welded Bottom
300 = 300 μm

For Example:


SFB Series Standard Felt Liquid Filter Bags - Polypropylene Felt - Size 1: Ø7"×16.5" - 5 μm - Plastic Ring - Fully Welded

Special specifications Standard Felt Liquid Filter Bags can be customized, such as special bag dimensions, ring style and seam etc.