High-Surface-Area Pleated Finger Elements for Pressure Leaf Filters

Skytech Ultrafab Pleated Finger Bags multiply the effective filtration area inside a pressure leaf or candle filter vessel by replacing flat bag surfaces with multiple pleated finger elements extending from a common collar. The increased area reduces filtration pressure drop, extends run time between bag changes, and allows higher throughput within the same vessel footprint — making them the preferred choice for edible oil polishing, pharmaceutical liquid clarification, and high-volume chemical filtration.

What Are Pleated Finger Bags?

Pleated Finger Bags are multi-lobe filter elements where several cylindrical or pleated fingers extend from a single mounting collar fitted to the filter vessel outlet. Each finger is fabricated from woven or membrane filter cloth, and together they present many times the filtration surface of a single bag of equivalent collar diameter. This geometry is particularly valuable in pressure filtration where maximising cloth area per vessel position directly increases throughput and reduces cleaning frequency.

Features and Benefits

• High Filtration Area: Multiple fingers per collar provide 3–6× the filtration area of a standard flat bag — directly translating into longer run times and lower pressure drop at equivalent flow rate
• Woven or Membrane Fabric: Available in woven PP, PES, nylon monofilament, or PE membrane media — cover the full range of liquid filtration micron ratings from 1 µm to 500 µm
• Precise Collar Fit: Mounting collar fabricated to the exact vessel outlet or leaf frame dimension — positive seal prevents bypass of unfiltered liquid into the filtrate channel
• Food-Grade Options: FDA 21 CFR-compliant PP and PES fabrics available for edible oil, beverage, pharmaceutical, and food-grade liquid filtration applications
• Reusable Construction: Robust woven fabric fingers withstand multiple cleaning cycles by back-flushing, low-pressure washing, or chemical regeneration to recover permeability
• Custom Finger Count: Two, three, four, or more fingers per collar available — finger count and length optimised to the vessel geometry and filtration area target

Technical Specifications

Applications

• Edible Oil Refining: Polishing of palm, sunflower, and soya oil after dewaxing and bleaching — high throughput at low pressure drop with food-grade fabric compliance
• Pharmaceutical Liquids: Clarification of syrups, tinctures, and injectables in horizontal pressure leaf filters in pharmaceutical liquid manufacturing
• Beverage Production: Beer, wine, juice, and carbonated beverage polishing — finger bag geometry maximises throughput per vessel within limited plant floor space
• Chemical Polishing: Removal of catalyst fines, precipitate, and insoluble residues from specialty chemical process streams in candle and leaf filter vessels
• Lubricant Refining: Spent clay and fine particulate removal from base oil in horizontal pressure leaf filters for lubricant and white oil production

Why Choose Skytech Ultrafab for Pleated Finger Bags?

• Bespoke Geometry: Any collar diameter, finger count, and finger length designed to match the exact filter vessel — maximum area utilisation without vessel modification
• Multi-Material Range: Woven and membrane media in all filtration-relevant materials from a single manufacturer — no need to source different elements from multiple suppliers
• GMP Documentation: Material certificates and FDA declarations provided for pharmaceutical and food industry qualification and audit requirements
• Long Service Life: Robust woven construction designed for repeated cleaning cycles — significantly lower cost per litre filtered versus disposable flat bag alternatives
• Fast Fabrication: Standard collar sizes in 7–10 working days; custom geometries from approved drawing in 12–15 working days