PP Melt-Blown Cartridge 40" Dual Gradient 1-10 µm

40" polypropylene melt-blown cartridge

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

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.

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

Dual gradient 1-10 µm

This is the key feature. Media density is not uniform: the outer layer is open at 10 µm, the inner layer tightens to 1 µm.

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

At 1 micron, this principle is not merely an advantage, it is essential. A single-density 1 µm cartridge blinds on its outer face alone and saturates within days as soon as the water carries any load. Here the cartridge uses its whole volume: at identical final rating, dirt-holding capacity and service life become usable.

The finest in the series

The Big One series covers three complementary positions in the chain.

The 20-50 µm is coarse duty: it absorbs the heavy load at the head of the installation.

The 5-20 µm is fine filtration at high flow, protecting softeners, membranes and heat exchangers.

The 1-10 µm is clarification. Its 1 micron final rating captures what the others let through: silt, suspended clays, precipitates, fines shed by upstream stages. It is the rating that genuinely clears water already clean to the eye.

It is also the rating generally required upstream of a UV lamp or a membrane, where any residual particle screens the radiation or fouls the active surface.

Do not install it alone

A 1-10 µm cartridge placed directly on raw water absorbs the whole particulate load and blinds very quickly, despite its volume.

Best practice is to fit it as the last stage, behind a 20-50 µm and, on loaded water, a 5-20 µm. Each cartridge absorbs the load the next must not see. The upstream stages cost less and multiply the service life of the 1-10 µm.

Where to use it

For final clarification at high flow: collective water treatment, industrial process, bottling, precision irrigation, protection of nozzles, dosing pumps and heat exchangers, prefiltration ahead of RO or UV.

Replacement

Replacement is driven by pressure drop, not by the calendar. A rising differential pressure across the filter, or a visible drop in flow, signals a blinded cartridge.

At this rating, service life is mechanically shorter than at 5-20 or 20-50 µm on the same water, that is the price of fineness, and precisely what the prefilters extend. A saturated cartridge left in place throttles the flow of the whole installation and can eventually release part of what it had captured.