PP Melt-Blown Cartridge 40" Dual Gradient 20-50 µm

40" polypropylene melt-blown cartridge

Sediment cartridge in pure polypropylene, 40" long, Big One format. Its length provides a very large filtration area, making it suited to high-flow installations and applications where long service intervals matter.

The melt-blown process

Melt-blown extrudes molten polypropylene fibres and blows them continuously around a core. The result is a media in one piece, with no binder, no additives and no adhesive, nothing that can migrate into the filtered water.

Unlike a string-wound cartridge, whose structure is a wound yarn, the melt-blown structure is a dense web of microfibres. It gives more consistent retention and a lower initial pressure drop at equivalent rating.

Dual gradient 20-50 µm

This is the key feature. Media density is not uniform: the outer layer is open at 50 µm, the inner layer tightens to 20 µm.

Water therefore passes through increasing density. Coarse particles, sand, rust, scale, are stopped at the surface, in the open zone. Fines travel further and are retained in depth, in the dense zone.

The benefit is direct: instead of blinding on its outer face like a single-density cartridge, this cartridge uses its whole volume. The result is significantly higher dirt-holding capacity and longer service life at identical final rating.

Where to use it

As sediment prefiltration on high-flow installations: collective water treatment, industrial process, irrigation, feed to a softener or to a downstream treatment train. The 20 µm final rating makes it a first barrier: it protects finer stages (5 µm, 1 µm, carbon, membrane) by removing the coarse load.

Replacement

Replacement is driven by pressure drop, not by the calendar. A clearly rising differential pressure across the filter, or a visible drop in flow, signals a blinded cartridge. A saturated cartridge left in place drags down the flow of the whole installation and eventually releases part of what it had captured.