Overview
Stainless steel pleated filter elements are high-performance filtration components using stainless steel as the base material. By increasing the filtration area through pleating technology, they achieve efficient interception of impurities in liquids or gases. Their core advantages lie in the corrosion resistance, high-temperature tolerance, and high strength of stainless steel, making them suitable for harsh scenarios with strict weather resistance and filtration precision requirements in chemical, pharmaceutical, food, water treatment, and other industries. Compared with traditional filter elements, the pleated structure increases the filtration area by 3-5 times in a limited space while maintaining micron-level filtration precision, serving as a key component for modern industrial precision filtration.
Working Principle
I. Material and Structural Design
1. Substrate Characteristics: Made of medical-grade stainless steel such as 304 and 316L, forming a microporous structure through weaving or sintering. It resists acids, alkalis, and organic solvents, operating stably within the temperature range of -20°C to 400°C.
2. Pleating Process: The stainless steel filter media are folded into corrugated shapes, fixed by laser welding or mechanical compression to form a high-density filtration layer. The filtration area of a single element reaches 1-10㎡, significantly increasing the flux (up to 5-10m³/h).
II. Filtration Mechanism
1. Deep-Bed Interception: Fluids flow from the outer side to the inner side of the element. Impurities are intercepted by stainless steel mesh pores or sintered pores, with particles larger than the pore size (0.1-100μm) retained, and clean fluids flow out from the inner side.
2. Gradient Filtration: Some elements use superimposed multi-layer stainless steel meshes (e.g., coarse, medium, fine layers) to achieve gradient interception from large particles to tiny impurities, enhancing the dirt-holding capacity (up to 1-3kg/m²).
III. Cleaning and Regeneration
1. Backwashing: Clean fluids (water or gas) are used for reverse flushing, combined with ultrasonic vibration to remove impurities attached to the filter media, allowing 50-100 repeated uses.
2. Chemical Cleaning: For oily contaminants, acid or alkali solutions can be used for cyclic cleaning. The stainless steel material does not react with chemical reagents, ensuring stable element performance.
Performance Characteristics
I. Resistance to Extreme Conditions
- Corrosion Resistance: 316L stainless steel has an annual corrosion rate <0.1mm in 10% nitric acid or 30% sodium hydroxide solutions, suitable for strong acid-alkali systems in chemical industries.
- High Temperature and Pressure Resistance: Withstands 1.6MPa pressure and 400°C high temperature, commonly used for steam sterilization or high-temperature fluid filtration (e.g., heat-conducting oil, molten polymers).
II. High Precision and Flux
- Filtration Precision: Sintered stainless steel elements achieve 0.1μm (intercepting bacteria and colloids), while woven mesh elements reach 1-100μm, meeting diverse needs (e.g., 0.22μm for electronic-grade water filtration).
- Flow Advantage: The flow rate of pleated elements is 3 times that of ordinary cylindrical elements. For example, a 10-inch pleated element has a water flux of up to 2m³/h.
III. Long Service Life and Environmental Friendliness
- Reusability: Under normal conditions, the service life is 2-5 years, reducing replacement frequency by 80% compared to PP elements and minimizing solid waste discharge.
- Recyclability: The stainless steel material can be 100% recycled after disposal, complying with environmental protection requirements.
IV. Strong Compatibility
- Medium Adaptability: Capable of filtering viscous liquids (e.g., ink, syrup), high-temperature gases (e.g., compressed air), and corrosive fluids with particulates.
Structural Components
I. Filter Media Body
- Woven Mesh Element: Formed by weaving 316L stainless steel wires into plain or twill meshes with uniform pore sizes, suitable for 1-100μm filtration.
- Sintered Element: Stainless steel powder is sintered at high temperature into a porous structure with a porosity of 35%-50%, suitable for 0.1-10μm precision filtration.
II. Support and Sealing System
- Central Tube: Stainless steel tube providing structural support with a pressure resistance ≥2MPa.
- End Caps: Made of stainless steel or PTFE, sealed by O-rings to prevent fluid bypass.
III. Connection Interfaces
- Standard Interfaces: Compatible with international standards like 222, 226, and M30 for easy installation and replacement.
Application Cases
I. Chemical Industry
- Catalyst Recovery: A petrochemical enterprise uses 10μm stainless steel pleated elements to recover catalyst particles in polyethylene production, achieving a 99.5% recovery rate and an annual cost saving of 2 million yuan on catalysts.
- Solvent Filtration: In pharmaceutical intermediate production, 316L elements filter dichloromethane solvent, resisting organic solvents with a service life of 3 years (PP elements last only 6 months).
II. Food and Beverage
- Beer Clarification: A craft brewery uses 0.45μm sintered elements to filter fermentation broth, intercepting yeast and proteins. The filtrate turbidity <0.5NTU eliminates the need for filter aids.
- Edible Oil Degumming: In palm oil refining, 5μm pleated elements remove phospholipid impurities, increasing oil yield by 2% and meeting food-grade hygiene standards (FDA certified).
III. Pharmaceutical Field
- Water for Injection Filtration: 0.22μm stainless steel sintered elements, combined with steam sterilization (121℃/30min), meet GMP standards, with a bacterial interception efficiency >99.99%.
- API Purification: In cephalosporin antibiotic production, 1μm elements remove crystal impurities, increasing product purity from 98.5% to 99.8%.
IV. Water Treatment
- Seawater Desalination Pretreatment: A coastal desalination station uses 5μm stainless steel pleated elements to filter seawater, resisting chloride corrosion (Cl⁻ concentration >20,000ppm), with a backwashing cycle of 72 hours (PP elements only last 24 hours).
- Circulating Water Filtration: In a power plant's cooling water system, 20μm elements intercept algae and sediment, reducing heat exchanger scaling by 70% and energy consumption by 15%.
Conclusion
Stainless steel pleated filter elements excel in corrosion resistance, high-temperature tolerance, and long service life due to material advantages and structural innovations, particularly suitable for harsh conditions where traditional filter materials fall short. With the increasing environmental and efficiency requirements in chemical, pharmaceutical, and other industries, their reusability and high recycling rate will further expand application scenarios. In the future, combined with nanocoating technologies (e.g., superhydrophobic stainless steel) and intelligent monitoring (integrated pressure difference sensors), stainless steel pleated filter elements will develop toward higher precision and intelligence, becoming core components in high-end filtration fields.
