LEFILTER Replacement Coalescer Filter Element for FAUDI Model D.1-842

1. Product Overview

The FAUDI D.1-842 is a widely recognized model in the D-series coalescer element family, frequently specified for aviation fuel handling and hydrocarbon separation applications. LEFILTER's replacement version is manufactured to exact OEM dimensional standards, ensuring seamless interchangeability with the original FAUDI element while incorporating upgraded material formulations that enhance contaminant holding capacity and coalescing efficiency.

This replacement coalescer filter element is constructed using high-purity borosilicate glass fiber media with a progressive density gradient. The outer layers capture larger particles while the inner hydrophilic fiber network targets micron-sized water droplets. Through coalescence, tiny droplets merge into larger droplets that separate by gravity, allowing purified fluid to continue downstream.

3. Filtration Mechanism

Stage 1 – Mechanical Filtration:
The outer coarse fiber layer traps large solid particles, rust, scale, and other mechanical impurities, protecting the inner precision media from premature clogging.

Stage 2 – Water Coalescence:
The fluid enters the hydrophilic borosilicate glass fiber matrix with gradient pore structure. As tiny emulsified water droplets pass through the dense fiber network, they are captured and held by the fibers. Continuous fluid flow causes captured droplets to collide and merge into larger droplets. Once droplets reach a critical size, gravity separates them into the collection sump.

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4. Structural Advantages

Aviation-Grade Gradient Glass Fiber Media
High-purity borosilicate glass fibers with progressive density gradient trap larger contaminants in outer layers while inner layers capture sub-micron particles. Super-hydrophilic surface treatment ensures consistent coalescing performance.

Reinforced End Caps
Precision-molded from glass fiber reinforced polyamide, matching exact interface dimensions of original FAUDI D.1-842 for drop-in installation.

NBR Sealing System
High-quality Buna-N O-rings provide zero-leakage sealing under fluctuating pressure, preventing bypass flow that compromises filtration efficiency.

Epoxy-Coated Steel Support Core
Robust central tube prevents media collapse under high differential pressure; epoxy coating ensures corrosion resistance.

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5. Applications

• Aviation fuel depots and refueling vehicles

• Petroleum refineries and processing plants

• Bulk fuel storage terminals

• Industrial light hydrocarbon systems

• Power generation and marine fuel treatment

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6. Quality Assurance

Every LEFILTER D.1-842 coalescer element undergoes stringent factory testing with compliance to:

• ISO 2941 – Collapse and burst resistance

• ISO 2942 – Fabrication integrity and bubble-point testing

• ISO 16889 – Multi-pass performance testing

• EI 1581 – Aviation water separation requirements

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7. Frequently Asked Questions

Q1: Is the LEFILTER D.1-842 a direct replacement for the original FAUDI D.1-842?
Yes. The LEFILTER D.1-842 is manufactured to exact dimensional specifications and sealing requirements of the original FAUDI element. It is a true drop-in replacement requiring no modifications to the filter housing or piping.

Q2: What fluids can the LEFILTER D.1-842 handle?
The D.1-842 is compatible with aviation kerosene, Jet A, Jet A-1, diesel fuels, gasoline, turbine oils, and various light hydrocarbon solvents. It is not recommended for strong acids, alkalis, or polar solvents.

Q3: When should the LEFILTER D.1-842 be replaced?
Replace when differential pressure reaches 1.0 bar (15 psi), or upon visible media deterioration, significant decline in water removal efficiency, or particulate breakthrough. Typical service life is up to 36 months.

Q4: Why choose LEFILTER over OEM?
LEFILTER offers equivalent performance at significantly lower cost, upgraded media with higher dirt holding capacity, stable global inventory with shorter lead times, and full ISO-certified quality compliance.

Technical Specifications