Parker I-633MMTB – Aviation Fuel Coalescer Cartridge

The Parker Velcon I-633MMTB is an EI 1581-qualified aviation fuel coalescer cartridge designed for first-stage filtration in filter/separator vessels used across commercial, military, and general aviation fueling operations. Featuring a multi-layer pleated fiberglass media construction, inside-to-outside flow direction, and a threaded base end cap, the I-633MMTB delivers 0.4-micron filtration efficiency with superior dirt-holding capacity — keeping jet fuel clean and dry at every fueling event.

How Coalescer Cartridges Work

Coalescer cartridges are employed as the critical first stage in two-stage filter/separator vessels for hydrocarbon fuels. The I-633MMTB performs two simultaneous functions: it coalesces highly dispersed, emulsified water particles — combining them into larger water droplets that can be removed by the downstream separator stage — and filters out solid particulate contaminants from the fuel stream. This dual-action filtration is the primary defense against water and particulate contamination reaching the aircraft fuel system.

Key Features

• 0.4-micron filtration efficiency with multi-layer pleated fiberglass media for superior dirt-holding capacity
• Inside-to-outside flow direction — industry-standard configuration for filter/separator vessels
• Threaded base (TB) end cap eliminates cover plates, gaskets, and hardware — simplifies installation and replacement
• Rated for use with pre-mixed fuel containing anti-icing additive (FSII) — critical for military and cold-weather operations
• EI 1581-qualified performance — meets stringent industry and military fuel filtration standards
• Compatible with Velcon vessels and other-make filter/separators including Facet, Faudi, Racor, Bendix, and Bowser/Keene/Kaydon housings
• Replaces CM-33SB-5, CM33-5SB, and CM-33-5SB legacy cartridges

Specifications

• Part Number: I-633MMTB
• Dimensions: 3.5" ID × 6" OD × 33" L
• Micron Rating: 0.4 µm
• Media: Multi-Layer Pleated Fiberglass
• Seal Material: Buna-N
• End Cap: Threaded Base
• Max Differential Pressure: 75 PSI (5.2 bar)
• Changeout Differential: 15 PSI (1 bar)
• Max Operating Temperature: 150–160°F (66–71°C)
• pH Range: 5 to 9 (continuous operation)
• Qualification: EI 1581

Applications

The Parker Velcon I-633MMTB is the correct cartridge for airport fuel farms, hydrant dispenser systems, fuel tankers, military refueling operations, FBO fueling stations, and MRO facilities managing filter/separator vessel maintenance. It is particularly suited to operations using pre-mixed Jet A or JP-8 fuel with anti-icing additive, and is a proven solution for aviation fuel quality compliance under EI 1581 qualification requirements.