English
English
METAMAX needle felt is an aramid-based dust filtration medium used where standard polyester no longer has enough thermal margin but the process does not necessarily require the extreme temperature range of P84, FMS or specialized fiberglass systems. Feierte’s current METAMAX product page describes the material as a blend of approximately 95% meta-aramid and 5% para-aramid fibers, with continuous operating temperatures around 200–204°C and short peaks up to about 220°C. The material is positioned for asphalt mixing plants, carbon black production, dryers, calcining systems, cement, metallurgy and other industrial baghouse applications.
For industrial buyers, METAMAX should be evaluated as a high-temperature mechanical workhorse rather than as a universal chemical filter. Its value lies in dimensional stability, abrasion resistance, repeated flexing tolerance and a useful high-temperature range. Feierte also highlights resistance to weak acids, weak alkalis and various organic solvents. When stronger acids, aggressive oxidizers or especially wet corrosive gas dominate, PPS or PTFE may be more suitable depending on the exact operating conditions.
The 95/5 meta-aramid and para-aramid blend referenced on Feierte’s page is intended to combine thermal resistance with mechanical strength. Meta-aramid provides the heat-resistant matrix, while the para-aramid portion contributes structural reinforcement. In a needle-punched felt, these fibers are mechanically entangled around a supporting scrim to form a robust filter medium that can tolerate repeated pulse-jet movement.
This mechanical stability matters because filter bags are not static. Every cleaning pulse flexes the bag against the cage. Abrasive particles strike the dust-facing surface, and temperature cycles create expansion and contraction. A media that maintains length and diameter helps prevent sagging, cage rubbing and sealing problems at the tubesheet.
| Selection Item | Feierte METAMAX Reference | What the Buyer Should Confirm |
|---|---|---|
| Continuous temperature | Approx. 200–204°C | Actual long-term inlet temperature after considering process load changes |
| Peak temperature | Approx. 220°C | Duration and frequency of thermal excursions |
| Fiber composition | Approx. 95% meta-aramid / 5% para-aramid | Confirm the exact grade and construction on the approved specification |
| Chemical direction | Resistance to weak acids, weak alkalis and various organic solvents | Strong acids, hydrolysis risk and oxidizing gases require separate review |
| Finishes | Singeing, heat setting and calendaring are highlighted | Choose finish based on dust release, permeability and cleaning behavior |
| Safety characteristic | Feierte describes inherent flame-retardant/self-extinguishing behavior | Do not treat media flame behavior as a replacement for complete baghouse fire protection |
Hot-mix asphalt production is one of the most recognizable applications for aramid filter media. Dryer exhaust carries hot mineral dust that can be abrasive, and temperature can change rapidly with burner settings, aggregate moisture and plant throughput. Feierte positions METAMAX for this environment because its thermal stability helps the bag maintain shape while the aramid structure resists mechanical wear.
Dust release is also important. Fine mineral dust mixed with traces of asphaltic material can become adhesive. Feierte lists singeing, heat setting and calendaring, which create a smoother dust-facing surface and support pulse cleaning. If an asphalt plant experiences rising differential pressure after startup, engineers should review burner control, moisture, bag surface finish and pulse settings rather than assuming that all aramid felts will behave identically.
Carbon black is an unusually fine, lightweight and penetrative particulate. Feierte specifically identifies carbon black production as an application for METAMAX. Fine soot can enter the felt structure and become difficult to remove, so surface smoothness and controlled permeability are critical. A calendared surface can reduce deep penetration and help the cleaning pulse detach the dust cake.
Because carbon black is also combustible, the filtration media is only one part of the safety system. Grounding, spark control, temperature monitoring, explosion protection and housekeeping must be designed around the process hazard. The aramid’s flame-retardant behavior can be a useful material property but should not be presented as complete risk mitigation.
Industrial dryers and calciners frequently operate near the temperature range where polyester becomes unsuitable. Aramid offers a practical intermediate solution for applications with hot air, mineral dust, organic solids or weakly corrosive vapor. Feierte highlights its dimensional stability under prolonged heat and its resistance to weak acids and alkalis. The moisture profile should still be reviewed because repeated condensation or aggressive chemical exposure can change fiber life.
For dryer exhaust, the dust’s stickiness often changes with temperature. Material that is dry at one temperature can become tacky when gas cools. Insulation, baghouse inlet control and surface finishing therefore have a direct relationship with filter pressure drop.
| Alternative | Compared with METAMAX | Best Reason to Choose the Alternative |
|---|---|---|
| PPS needle felt | Similar general high-temperature class but different chemistry focus | Acidic, humid flue gas and hydrolysis resistance where oxygen remains suitable for PPS |
| P84 needle felt | Higher published temperature capability and trilobal fibers | Very hot fine-dust filtration where submicron capture and low pressure drop justify premium media |
| FMS composite felt | Composite fiberglass/synthetic structure for severe heavy-industry service | Extreme temperature, high abrasion or a need for reinforced composite behavior |
| PTFE needle felt | Much broader chemical inertness | Strong acids, alkalis, oxidants and difficult mixed corrosive gas |
Feierte’s METAMAX page lists singeing, heat setting and calendaring. Singeing reduces protruding fibers, heat setting improves dimensional stability and calendaring creates a smoother surface. These treatments can reduce dust penetration and improve cake release, but they also influence permeability. The finished specification should therefore be linked to the baghouse air-to-cloth ratio and cleaning method.
A plant converting from polyester to aramid sometimes expects pressure drop to improve automatically. In reality, a new aramid felt with unsuitable weight or finish can have higher resistance than the previous PET product. The correct comparison is between approved constructions under the same dust loading, not between fiber names alone.
Aramid felt can be fabricated into pulse-jet, reverse-air or shaker bags depending on the collector design. Finished dimensions, cuff, snap band, bottom and cage interface must match the tubesheet. High-temperature bags require particular care around cage corrosion and burrs because the media can be expensive to replace. A small sharp point can create a failure independent of thermal capability.
For large asphalt or metallurgy projects, it is useful to control bags by a technical drawing and fabric code. This prevents future orders from drifting between different aramid weights, scrim structures or finishes that all carry the same broad “aramid filter bag” description.
METAMAX is generally more expensive than polyester, so the purchasing case should be based on thermal reliability, bag life, pressure-drop stability and reduced shutdown risk. If the current PET bag is failing from heat shrinkage, aramid can solve a clear material mismatch. If the current problem is acid corrosion or severe oxidation, changing to aramid may not address the true cause.
Track operating hours, pressure drop, pulse frequency and failure mode after installation. Comparing cost per operating hour rather than price per bag provides a more meaningful B2B metric. Feierte can also use failed-bag samples to distinguish abrasion, thermal damage and chemical degradation.
Provide the normal and maximum gas temperature, dust type, gas chemistry, moisture, cleaning system, baghouse pressure drop and current media. For finished bags, include diameter, length, cuff, bottom and cage dimensions. If the application is asphalt, carbon black or a dryer, also identify any sticky-dust or abrasion problem.
Submit the application data through the Feierte Contact Us page. Feierte can then review whether METAMAX is appropriate, which finish should be used and whether PPS, P84, FMS or PTFE would provide a better safety margin under the actual chemistry and temperature profile.
Feierte's current METAMAX page lists approximately 200–204°C continuous operation and peak temperatures around 220°C. The final allowable range should be confirmed against gas chemistry, humidity and the exact felt construction.
Feierte highlights asphalt mixing, carbon black, dryers, calcining, cement and metallurgy. It is generally selected where high-temperature mechanical stability is required around the 200°C operating class.
No. Both are high-temperature synthetic filter media, but their chemical behavior differs. PPS is especially valued for acid and hydrolysis resistance in suitable oxygen conditions, while METAMAX is an aramid media valued for thermal and mechanical stability.
Feierte lists singeing, heat setting and calendaring on the current product page. These treatments are used to improve dimensional control and dust-cake release and should be selected against the baghouse permeability and cleaning requirements.
