HRSflow is completing the expansion of its 3,000-square-meter factory in San Polo di Piave, Italy. The expansion is designed according to lean production standards to make the hot runner assembly process more efficient. The goal is to ensure increased production capacity and provide customers with greater flexibility.
Since its introduction into the industry, hot runners have played a key role in improving the injection molding process. Although the capital cost is greater than that of cold runners, its ultra-high production efficiency makes it a long-term and more economical choice. The improvement of system performance can produce parts with excellent appearance and increase part functions. In addition, the hot runner improves energy efficiency and saves plastic raw materials, thereby shortening cycle time and reducing part costs.
TZM hot runner nozzle
In view of the advantages of hot runners, the world's large and small enterprises, including those mentioned above, are implementing hot runners and seeking various solutions for further optimization. Of course, the focus of this article is not on this, but on one of the important parts of the hot runner-the nozzle.
The hot runner technology is mainly to heat the plastic melt between the injection molding machine nozzle and the cavity to reduce the injection pressure, so that the plastic melt can fill the cavity smoothly, so as to obtain high-quality plastic products. The choice of nozzle material is related to the production efficiency, cost and quality of the finished product of the hot runner system.
Pure molybdenum has a very high melting point, good strength, low thermal expansion coefficient and excellent thermal conductivity, and is a good comprehensive candidate material for most high-temperature applications. TZM is an acronym for "Titanium-Zirconium-Molybdenum", which is a molybdenum alloy. Like pure molybdenum, TZM can be produced by powder metallurgy.
Although TZM is 25% more expensive than pure molybdenum, in some applications, the additional cost is offset by its increased strength at high temperatures. The recrystallization temperature of TZM is higher than that of pure molybdenum, which reduces the possibility of embrittlement at high temperatures. In high temperature applications, TZM has higher strength, hardness, creep resistance and ductility, which can ensure that it will not weaken or become soft.
Therefore, titanium-zirconium-molybdenum alloy is currently a suitable material for nozzles. TZM hot runner nozzles have the following advantages: no traces of the gate are left on the product, and the traces at the gate are smooth; larger diameter gates can be used, which can speed up the filling of the cavity and further reduce the injection pressure. Small product deformation; can prevent the phenomenon of dragging and drooling when the mold is opened; when the screw of the injection molding machine is retracted, it can effectively prevent the material from sucking back from the cavity; it can cooperate with the sequence control to reduce the welding mark of the product.