The German firm of i-mold GmbH & Co.KG, Brensbach/Germany, recently introduced its new SGC series of contourable tunnel gate inserts for a considerably extended range of applications. These new tunnel gate inserts differ from the previous design of insert in that the runner opens from the front side but the actual gating surface can be located exactly where desired, depending on the design and function of the moulded part. The SGC series of tunnel gate inserts is ideal for applications where, for example, the injection point has to be positioned deep inside the moulded part. A typical example is the side-gating of a rib below the outer edge of the moulded part. The result is a moulded part without any visible gate marks on the side exposed to view. The new tunnel gate inserts recently made their début at Euromold in Frankfurt am Main/Germany.
The new SGC tunnel gate inserts are available in three sizes for maximum shot weights of 40, 140 and 1100 g respectively. They are suitable for all standard and engineering plastics, and also for filled or reinforced materials. An integrated dead-end recess reduces pressure loss and shear stress. The sprue in the runner can be readily and reliably removed, provided that a certain distance, which is dependent both on the type of material and on the size of insert, is maintained between the gate and the ejector. 3D or 2D-CAD data are available for all gate inserts, permitting easy integration into the mould designing process. Like all tunnel gate inserts from i-mold, the new SGC inserts are machined from highly wear resistant steel and have a hardness of 54 HRC.
Multi-cavity moulds can be manufactured at particularly low cost if the tunnel gate inserts are combined with the LKM Heatlock hot runner systems also included in i-mold's sales portfolio. This combination, in which one hot runner nozzle feeds several – mostly 4 to 6 – tunnel gate inserts, offers a great many advantages: even in moulds with a large number of cavities, only a relatively small and hence low-cost hot runner system is required. Moreover, the relatively simple constructional features of the mould not only make for a reduction in size but also ensure extreme reliability of operation.