Theory behind the Magnom™
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As with all good ideas, the patented Magnom™ design is fundamentally simple. Fluids are cleaned of ferrous [iron & steel] particles by a magnet. The strength of the magnetic field is dramatically enhanced by the field effect of two metal plates placed at either end of the magnet. The enhanced field pulls the ferrous particles out of the fluid flow, without disturbing the liquid.
Again, as always, it is the detail that makes the difference:
The magnets are slim cylinders, whose outer diameter is 40mm or more [product dependant].
The field effect plates are quite thin, but substantially larger in diameter than the magnet, and have U shaped channels cut out round the cicumference. One magnet and its two field plates are known as a core.
Cores are stacked on a central mandrel, and located inside a snug fitting plastic or metal cannister. The canister and its cores consitute a Magnom™ unit. The number of cores in a unit varies between 1 [for Formula 1 cars] and 20 [for heavy duty industrial process protection].
Magnetic gradients
The fluid can only flow through the U channels, and is therefore forced to pass through regions of high magnetic gradient - just what is required for effective cleaning! The Magnom™ is particularly adept at collecting particulates in the 0.1 to 20 micron regions, which, as we have seen is the critical size for causing maximum wear in fluid systems.
An equivalent conventional barrier filter would be so fine as to introduce massive pressure drops, and would very quickly fill, requiring a significant amount of maintainance.
Suprisingly, the Magnom™ can also remove some non-ferrous particulate, when ferrous particles are present, by a process termed heterocoagulation. This process is driven by both surface molecular and macroscopic effects.
Magnom™ also breaks up harmful bacteria which grow in diesel fuels. These bacteria are disrupted by the strong magnetic fields, broken down into smaller particles and thus prevented from reproducing and creating bio-films - a valuable bonus when conditioning fuels in long term storage.
On the other hand, the magnetic field does not cull performancing enhancing additives, which are left to do their job properly, thus reducing the need for constant replenishment and saving on consumables.
Collection zones
The particles are actually drawn by the field, out of the main flow and into the collection areas between the plates. These spaces are effectively dead spaces or backwaters, so the collected contaminants are protected from the pressure in the flow channels - hence there are no problems with wash-off.
The size of the channels is designed to be 110% of the entrance diameter, so that there is no ‘choke’ on the flow, and the pressure drop is negligable. Because the Magnom™ is immune to pressure, it can actually work on the suction side of powerful pumps - the only filter able to provide effective protection to this critical components.
The collection areas are actually three dimensional spaces, and so the unit can collect and safely store several times the contaminant of a conventional barrier filter, and all without impeding flow. There are no moving parts to seize up, and no papers to split with disasterous consequences for down stream machinery.
Other features
The Magnom™ can be made in a vast range of sizes - and is just as efficient with a large as a small core.
The Magnom™ can condition almost all liquids with an element of ferrous contaminant; this includes water, oils, and machining fluids. This can be achieved even at great:
- pressures (140 bar +)
- flow-rates (500 l/minute +)
- viscosities (10,000cST +)
- temperatures (350C +).
Agressive environments can be handled with the appropriate choice of construction materials.
The Magnom is inherently bi-directional [although some units are uni-directional as a consequence of design features] and can even handle fluids pulsating in both directions.
Performance example
Here we show just one example of the performance offered by the Magnom™ filter, demonstrating its ability to remove ferrous particles and its ability to collect non-ferrous contaminants by heterocoagulation.
Bridgnorth Aluminium, a major producer of rolled Aluminium product employed Magnom™ for the protection of Industrial Transmissions. At their Bridgnorth plant in the UK, oil analysis identified a significant presence of ferrous contamination and other wear elements within a number of lubrication circuits on key transmissions driving their Hot Rolling Mills. Subsequent visual gear survey identified significant and progressive wear with a real risk of catastrophic failure.
To alleviate this, a Magnom™ Process Unit was installated on a Tandem Mill Lubrication Circuit (1000 litre capacity, Glycolube) in an offline (dialysis) configuration.
This graph shows the Iron, Lead & Copper contaminant levels before introduction of the unit, and over a 8 week period of operation.
The extent of debris removal (both ferrous and non ferrous) witnessed and backed up with impressive oil analysis data was truly remarkable. Clearly this has lead to an extension of transmission life and up time with major associated cost savings, as a result of this success Magnom™ is now being specified for transmission and other applications thoughout the Company.