Archive for 9 July, 2012

Extrusion dies with split nibs (I). Concentricity

Tungsten carbide dies can have different sizes: from very large to very small. For quite some time, tooling manufacturers have succeeded on developing its technology for cutting the nibs on long enough dies, thus reducing manufacturing costs. Of all tungsten carbide dies, the most demanding for this technology are the extrusion dies, because of the high pressures they are submitted to, which can cause that the upper nib is expelled from the casing.


Is it possible to split the upper nibs?


TEMSA does it quite frequently and with very good results. The nib is cut at a suitable distance above the extrusion. Many customers ask how we can overcome the concentricity problems between the upper and the lower nib. Any small variation will cause the material to grip and eventually breaking the die. TEMSA solves this problem by smoothing the sharp edges on both tungsten carbide nibs creating a small bevel on both edges. This problem can also be solved by making a small radius. Furthermore, the joint of both nibs can be used for adding air events. With this simple method, we can solve those concentricity problems that could appear on the nibs.


Detalle de unión entre núcleos de metal duro para evitar desconcentricidad

Detalle de unión entre núcleos para evitar evitar desvíos de concentricidad