Quality
Assurance
Advantage Vihan
The selection of the right type of Filtration Fabric has become very critical to get the best result from various Filtering equipments such as, Filter Press, Centrifuge, Neutch, Pressure Filters etc.
Vihan Filtration System, looks into each aspect of filtration process and its parameters, and applies expertise to obtain the maximum benefit, not only from weaving point of view, but also from the processing applied to the fabric. The Company is specialized in fabricating the madeups as per customers individual requirement of their equipments and for various products. Below are few of the processes:
Improper selection of Filter Media, leads to many hidden losses such as:
- Material loss, due to porous fabric
- Longer down time, due to selection of very close woven fabric
- Wear and Tear due to faulty measurements & stitching of stretched materials
The Company is committed to serve its customer with the best possible quality, by taking precautions at all stages of manufacturing, viz. production, processing, fabrication and followed by prompt deliveries.
Filter Media
Definition
| Fiber type | Polypropylene, Polyester, Nylon (Polyamide), Cotton |
| Type of yarn | Staple Fiber, Multifilament, Mono Filament |
| Weave | Plain, Twill, Satin and Chain |
| Finishing | Heat setting, Hydraulic treatment, Thermal stabilization, Chemical treatment, Calendaring |
| Weight | gms. per square meter |
| Air permeability | ft3 / ft2 / min |
| Tensile Strength | Kg-m |
| Breaking Elongation | % |
Best Results
Best results of Filter Media such as Retention, Flow Rate, Cake release and Longevity depends on various technical production factors.
| Requirements | Production Factors |
|---|---|
| Mechanical Strength | Fiber Type, Yarn type, Weave, Finish & Fabrication |
| Flow rate and Retention | Yarn Type, Weave & Finish |
| Suitability to Physical and Chemical environments | Fiber Type |
| Resistance to Blinding, Ease of Regeneration | Yarn Type, Weave & Finish |
| Price | All Factors |
Selection of Filter Media
The right selection of Filter Media defers mainly in terms or their resistance to temperature, acid and alkalis as well as the mechanical stress. The following table mentions the details of the resistance for each filter media:
Physical Characteristics
| Material | Moisture Absorption | Density resistance | Abrasion to UV | Resistance | Creasing | Type of Yanrs |
|---|---|---|---|---|---|---|
| Cotton | 7% | 1.50 | VP | PO | VP | F |
| Polypropylene | 0% | 0.91 | AV | PO | PO | C,F,M |
| Polyester | 0.4% | 1.38 | GO | AV | AV | C.F |
| Nylon | 4% | 1.14 | EX | PO | EX | C.F |
EX : EXCELLENT | GO : GOOD | AV : AVERAGE | PO : POOR | VP : VERY POOR
F : STAPLE FIBRE | M : MONO FILAMENT | C : CONTINUOUS MULTIFILAMENT YARN
Material
Polypropylene Fabrics
Polypropylene is a by-product of petroleum industry which has excellent strength and is very resistant to abrasion. It floats on water as it is light in weight with a specific gravity of 0.90 Polypropylene multifilament or spun yarns are used for various application such as filter fabric, luggage fabric, ropes, webbing etc.
Major properties
| Melting Point | 165°c |
| Operating Temperature | 90°c |
| Resistance to Feed Pressure | 2 bars to 20 bars |
| Effect of Acids and Alkalis | Excellent resistance to most acid and alkalis with exception of Chloro-sulfonic acid & Oxidizing agents |
| Effect of bleaches and solvents | Good resistance to bleach and solvents |
Polyester Fabric
Polyester is manufactured from the fiber forming substance in any long chain synthetic polymer composed of atleast 85% by weight of ester of a dihydric alcohol and terephthalic acid. Polyester fibers are melt and spun from elements coming from coal, air water and petroleum, Polyester fabrics are widely used for industrial application.
Major properties
| Melting Point | 225°c |
| Operating Temperature | 175°c |
| Resistance to Feed Pressure | 2 bars to 15 bars |
| Effect of Acids and Alkalis | Good resistance to most mineral acids
|
| Effect of bleaches and solvents | Excellent, except in some phenylic compounds |
Nylon Fabric
Nylon is a synthetic fiber made of coal, water and air, capable of being made into fine and coarse materials, Nylon is used filtration fabric, tyre fabric, luggage fabric, belting etc.
Major properties
| Melting Point | 175°c |
| Operating Temperature | 140°c |
| Resistance to Feed Pressure | 2 bars to 15 bars |
| Effect of Acids and Alkalis | Substantially inert in alkalis
|
| Effect of bleaches and solvents | Can be bleached in most bleaching agents, except chlorinated bleaches
|
Weaving And Filtration
| Fabric Properties | Type of Yarn | Weave Pattern | |||||
|---|---|---|---|---|---|---|---|
| Staple | Multi | Mono | Twill | Plain | Chain | Satin | |
| Retention | High | Medium | Medium | Medium | High | High | High |
| Flow Rate | Medium | Low | Low | Medium | Low | Low | Low |
| Cake Release | Low | High | High | Medium | Low | High | High |
| Blinding Resistance | Low | High | High | Medium | Low | High | High |
Finishing Treatment
A grey fabric is treated when necessary, to bring about the dimensional stability (Shrinkage or elongation), to reduce the air permeability, to increase the retention capacity, to enhance the Life Cycle and to reduce Material Loss. Some of the treatments meted out are as follows:
- Hydraulic Treatment
- Thermal Stabilization
- Chemical Treatment
- Calendaring
Applications of Filter Media
For Main Type of Filtration Equipment
| Filtration Principle | Pressure | Centrifugal Force | Vacuum | Gravity | |
|---|---|---|---|---|---|
| Hydraulic | Mechanical | ||||
| Continuous | Rotray Drum Discs | Belt Press | Centrifuge | Rotary Drum Table Filter Vertical Disc Belt |
Vibrating Screen Rotary Screen Drainage Belt |
| Batch | Filter Press Leaf Discs |
Vertical Press Membrane Press Horizontal Press |
Centrifuge | Neutch Bags Horizontal Discs |
Neutch Bags |