Customized all kinds of plastic porous filters
Your leading manufacturer for plastic porous filter?
Lvyuan's metal-plastic sintered cartridges combine the advantages of metal and polymer materials through the composite sintering process, combining high strength and corrosion resistance. The core of the process is: mixing metal powder such as stainless steel and copper with thermoplastic plastic such as polyethylene and PTFE in proportion to the addition of volatile agents (such as paraffin) to enhance the molding fluidity; then pressed by the mold and sintered at a high temperature of 300-900 ℃, the plastic fused to form a bonded network, the metal particles constitute a porous skeleton, and the volatile agents are completely decomposed to ensure the uniformity of the pore space.
The porosity of the finished product reaches 30-50%, the filtration precision covers 0.5-100μm, and at the same time, it has the characteristics of high temperature resistance of metal (up to 500℃) and chemical corrosion resistance of plastic, which is suitable for hydraulic system, high temperature gas filtration and purification of corrosive liquids and other scenarios, and the recovery rate of the performance is more than 80% after backwashing. This technology solves the contradiction between the strength and corrosion resistance of traditional single material filter element through material composite and gradient sintering, and at the same time reduces the production cost, providing efficient solutions for industrial environments such as chemical industry and water treatment.
What is plastic porous filter?
UHMW-PE is sintered and molded at high temperature with high porosity (30-50%), consistent pore size inside and outside, and chemical corrosion resistance.
Advantages: Resistant to strong acid and alkali, can be regenerated by backwashing, no degranulation, and meets the safety standards of food/pharmaceutical industry (e.g. FDA, GMP).
Technical parameters and specifications
- Filtration precision: 0.2-140μm (commonly used 0.45-50μm).
- Temperature range: conventional 80℃, short-term temperature up to 100-130℃ (to be adjusted according to the density).
- Pressure strength: 0.3-0.6MPa (high density sintered cartridge can be higher).
- Standard size
- Diameter: Φ20-Φ1000mm (support customized shaped parts).
- Interface type: M20/M30 thread, flat pressure type, quick-clip fastener, etc.
What are the features for plastic porous filter?
Filtration performance
- High porosity ensures high flow rate, smooth outer surface reduces impurity adhesion.
- The internal and external filtration precision is consistent, and it supports backwashing and desludging (physical/chemical methods).
Durability
- Resistant to impact and microbial erosion, with mechanical strength superior to ordinary polyethylene.
- Chemical stability: resistant to non-oxidizing acids, alkalis and organic solvents (e.g. alcohol, acetone).
How are the the production process of plastic porous filter?
1. Preparation of raw materials
- Powder selection: UHMWPE powder is used, the particle size of the powder is usually 50-200 mesh, and the distribution of the particle size should be strictly controlled to regulate the porosity of the cartridge.
- Additives: add lubricants (e.g. zinc stearate), antioxidants or functional fillers (e.g. activated charcoal, ceramic powders) as required to improve processability or functionality.
- Pre-treatment: Drying of the powder (to remove moisture) and sieving (to ensure uniform particle size).
2. Mixing and homogenization
- Add UHMWPE powder and additives proportionally to mixing equipment and mix thoroughly until homogeneous to ensure consistent material properties.
3. Mold filling
- Mold design: Design the high temperature resistant mold according to the shape of the cartridge (tube, sheet, etc.), and the inner surface of the mold should be smooth to reduce the resistance of demolding.
- Powder filling: Fill the mixed powder evenly into the mold, and make the powder distribution close by vibration or pressure to reduce the porosity defects.
4. Sintering molding
- Hot press sintering: Put the mold into the hot press and sinter it under specific temperature (slightly lower than the melting point of UHMWPE, about 130-150℃) and pressure (5-20 MPa). The sintering time is adjusted according to the thickness of the cartridge (usually 30-120 minutes).
- Process Control:
- Temperature: The rate of heating and holding time are precisely controlled to avoid material decomposition or excessive melting leading to pore closure.
- Pressure: Pressure induces a “necking” bond between the powder particles while maintaining the porous structure.
5. Cooling and demolding
- Slow Cooling: After the heat is turned off, the powder is cooled naturally to room temperature under pressure or low pressure to prevent internal stresses or distortion caused by rapid cooling.
- Demolding: Remove the sintered cartridge blank from the mold and inspect the surface for integrity.
6. Post-processing
- Machining: The cartridge is cut, polished or drilled to the required size and shape accuracy.
- Surface treatment: Optional chemical treatment (e.g. hydrophilic/hydrophobic modification) or plasma treatment to enhance filtration performance.
- Cleaning: ultrasonic cleaning or solvent rinsing to remove residual powder and impurities.
7. Performance Testing
- Porosity test: Determine the porosity and pore size distribution by mercuric pressure method or gas adsorption method.
- Strength test: Detect mechanical properties such as compressive strength and flexural strength.
- Filtration performance: Evaluate the filtration precision (e.g. retained particle size), flux and pressure resistance.
- Corrosion resistance: soak in acid/alkali/organic solvents to test material stability.
8. Packaging and storage
- Qualified cartridges are sealed and packed in dustproof bags to avoid contamination and stored in a dry, light-proof environment.
Key process control points
1. Powder particle size and distribution: directly affect the pore structure and filtration precision of the cartridge.
2. Sintering temperature and pressure: determine the bonding strength and porosity of the material.
3. Cooling rate: affects the microstructure and mechanical properties.
4. additive ratio: optimizes processability and functionality.
Areas of application
- Chemical industry: corrosive liquid/gas filtration.
- Water treatment: reverse osmosis pretreatment, sewage filtration.
- Food/Pharmaceutical: sterile filtration, high purity media treatment.
- Energy: fuel cell gas diffusion layer, catalyst carrier.
Maintenance and regeneration methods
- Physical cleaning: 0.6MPa compressed air blowback, restore 60-80% of the initial flow.
- Chemical cleaning: 5-10% acid/alkali solution immersion to dissolve the clogging material (applicable after long-term use).
- Life cycle: 1-3 years (depending on the frequency of working conditions).
How is our service?
Precision Selection Misconceptions: Not the higher the precision, the better, according to the particle size distribution of particles to choose.
- Chemical compatibility limitation: not resistant to strong oxidizing agents such as concentrated sulfuric acid.
- Customized service: shaped structure (sheet, tube, rod, etc.) and special size support.