Product description
Nomex felt filter bag for high temperature liquid filtration
The Nomex Felt Filter Bag, manufactured from aramid fibres, is designed for specialised liquid filtration applications involving elevated temperatures (up to 400C) and demanding operating conditions. Nomex is primarily known for its thermal stability and mechanical strength, making it suitable for filtration processes where standard polymer felts such as polypropylene or polyester are not sufficient.
Nomex filter bags are typically used in niche industrial applications where temperature resistance is the primary selection criterion rather than chemical compatibility.
Filtration principle
Nomex felt filter bags operate using inside to outside depth filtration. Process liquid enters the bag, flows through the aramid felt structure and exits the housing, while particles are retained throughout the thickness of the media.
This depth filtration mechanism provides:
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stable particle retention
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resistance to media deformation at high temperatures
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predictable pressure behaviour under thermal stress
All contaminants are retained inside the filter bag, allowing controlled and clean disposal during change out.
Material characteristics
Nomex is an aramid fibre designed for thermal and mechanical performance rather than broad chemical resistance. Its properties make it suitable for specific liquid filtration applications with elevated temperatures.
Key material characteristics include:
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excellent resistance to high temperatures
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strong mechanical strength and dimensional stability
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good resistance to abrasion
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low fibre migration
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suitability for hot oils and heat transfer fluids
Nomex is not a general purpose liquid filtration material and should be selected only when its specific properties are required.
Temperature performance and limitations
Nomex felt offers excellent thermal resistance in liquid filtration compared to most polymer felts, but temperature limits depend strongly on the fluid and operating conditions.
Typical temperature characteristics:
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suitable for continuous operation in hot liquid applications
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performs well with hot oils and heat transfer fluids
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retains mechanical strength at temperatures where polypropylene and polyester degrade
Important limitations:
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prolonged exposure to strong acids or strong alkalis can degrade aramid fibres
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hydrolysis can occur in hot water or steam environments
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not recommended for highly acidic or highly alkaline liquids
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not suitable for applications requiring broad chemical resistance
Correct material selection is essential to ensure safe and reliable operation.
Design and construction
Nomex felt filter bags supplied by Filtra International are manufactured for stability and durability in high temperature liquid filtration environments.
Typical design features include:
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aramid felt depth filtration media
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robust stitched or thermally bonded construction
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finished surface to reduce fibre migration
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sealing ring options to prevent bypass
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compatibility with standard industrial support baskets
The filter bag maintains its shape and integrity under elevated temperature conditions.
Available micron ratings
Nomex felt filter bags are available in commonly used industrial micron ratings.
Typical available ratings include:
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1 micron
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5 micron
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10 micron
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25 micron
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50 micron
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100 micron
Standard sizes
Nomex felt filter bags are supplied in standard industrial sizes.
Typical sizes include:
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Size 1
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Size 2
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Size 3
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Size 4
Custom sizes can be supplied on request.
Typical applications
Nomex felt filter bags are used in specialised liquid filtration applications such as:
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hot oil filtration
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heat transfer fluid filtration
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high temperature industrial process liquids
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speciality chemical processes with controlled chemistry
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applications where polymer felts cannot withstand the operating temperature
Key benefits
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Excellent high temperature resistance
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Strong mechanical stability under thermal stress
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Reliable depth filtration performance
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Suitable for specialised high temperature liquid applications
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Compatible with standard bag filter housings
Important selection considerations
Nomex felt filter bags should not be selected as a general replacement for polypropylene or polyester felt bags. Material compatibility with the process liquid, temperature and operating conditions must be carefully evaluated.
Filtra International can provide technical guidance to ensure correct material selection.
Configuration and quotation
Nomex felt filter bags are supplied based on application requirements. Selection parameters include:
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micron rating
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bag size
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operating temperature
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liquid chemistry