When it comes to hardness, Tungsten Carbide is second only to industrial diamond and is proven to outlast most metals. There is no surprise that it is now the most favoured way to create longevity and increase performance in agricultural wearing parts.
Being one of the first in the country to work with the material, J.J.Metcalfe & Son Ltd have over 10 years of specialised knowledge in the use and application of Tungsten Carbide. Although Tungsten Carbide can be welded onto other metals, J.J.Metcalfe & Son use a refined brazing method. This advanced technique creates a much stronger bond underneath the entire Tungsten Carbide tile which cannot be achieved by welding.
NG System Shins cooling after the brazing process
The fact that Tungsten Carbide extends the life of wearing parts is no secret, facts show that it can increase life by 4 to 10 times in comparison to heat treated steel, reducing down time and increasing time spent in the field. However, wear life is not only increased by the surface hardness of the Tungsten Carbide, a correctly designed component utilising Tungsten Carbide in the correct places will be much more efficient at penetrating and cutting the soil, resulting in minimal smear and compressive forces which would otherwise increase drag and fuel consumption.
Applying Tungsten Carbide in key areas protects the shape and design of the part, ensuring optimum performance throughout its entire life.
On a component without Tungsten Carbide, the edges wear becoming rounded and more likely to smear and compress the soil when running through it. This compressive, smearing action of a worn part acts on the soil at depth. Often this is at the ‘problem depth’ when soil loosening, or the key seedbed depth, critical for early crop emergence and essential root growth when cultivating. In either situation, smearing at this depth creates a barrier for root growth, water and air movement. These barriers created by smearing are worsened when soil is damp, effective water and air movement is vital for crop establishment and growth. These barriers can also create localised flooding which even when temporary will reduce plant growth and yield potential.
These diagrams show how the crop suffers when in compacted ground. The one on the left is suffering as it is unable to establish root growth and lacks oxygen and water. The crop on the right is doing well as it has room to grow and sufficient air and water movement.
In most cases with non Tungsten Carbide parts, wear life is improved by making leading edges thicker, the thought being that they will last longer before the part loses its length and lifting effect. However, this bulkier part will wear to a more severely rounded edge, further increasing the smearing.
Using Tungsten Carbide eliminates smearing, it enables the part to cut through the soil rather than compressing it, relieving compaction and giving drainage directly where it is needed. The self-sharpening property of Tungsten Carbide ensures the cutting edge will never round off, keeping its shape and high performance for the duration of its life.