זרקנים עם הברגה בראש
פינים/ זרקנים בעלי הברגה בראש לצורך חליצה מהירה מהתבנית. נועדו ליישום במקרה שרוצים החלפת פין ללא פירוק התבנית. הזרקנים עשויים מפלדה 1.2344, בקושי 42-46 HRC
Molds are becoming bigger and more complex, and often extraordinary maintenance costs or repairs have a huge impact on the final production cost.We take the case of the pins in die-cast aluminum molds. They are among the most subject-to-wear parts because they are immersed in melted aluminum, exposed to heat and corrosion due to die-cast alloys. In addition, metal bumps printed at hundreds of pressure bars weaken these plugs that can break during the workpiece extraction.We can improve the steel used to build them, optimize thermal treatments to ensure tenacity and resilience, coat them with high-temperature, corrosion-resistant coatings. But often this is not enough and extraordinary maintenance must still be done. So, it is important that it is as cheaper and complicated as possible.
Figure 1: Standard mounting of pins in the dowel. To replace them, you have to disassembly the mold.
Figure 2: Mounting standard pins in the base plate to allow quick and easy access without disassembling the mold.
Figure 3: Mounted threaded plugs in the locked dowel with flat screws, accessible through holes in the mold. Let's analyze the two solutions.
Figure 2: The solution is good, but it forces to use long and expensive pins, which become difficult to work and do not always guarantee the savings you would expect, adding workmanships even in the bottom plate.
Figure 3: Pedrotti has created pins (A) with a larger head and a threaded hole. Installed properly in the mold, you can simply extract it with a M6 screw in the threaded hole and a couple of tools in each workshop.
This installation requires a little more space around the pins, because it is important that the screw used (B) to lock them are properly dimensioned and guarantee a flat support and perpendicular to the molding axis.The extraction holes (C) have the function of passing the hexagonal wrench and allow the pin to be replaced without disassembling any part of the mold. Sometimes you can avoid drilling them on the bottom plate, which will be dismantled before maintenance.So, it generates considerable time savings when replacing the plugs, and money when purchasing. Also, the plug is of the right length for easy machining on a lathe or grinding.These pins are called EES-2CBH and are available in stock sizes from 5 to 20 with lengths of 160 and 250mm. They are made of 1,2344 steel, quenched at 42-46 HRC. Like all products in the Pedrotti catalogue, they can be constructed on customer's design and in special steels; they can be shaped, nitrided and coated with special corrosion-resistant coatings and at high temperatures.