Product: Girth Sprockets
Industry: Aggregate Processing
As rotating drums for processing aggregate materials have become larger, the room around them hasn’t. This has resulted in girth sprockets that need to be big enough for large roller chains or even engineered chains, but with much less height from the ring sprocket ID to the root diameter. The result for customers is less material for a lower cost than a big ring sprocket, but the downside is that the small cross-section makes for a very flexible part, referred to in the trade as a “noodle”. The challenge of manufacturing a part (that has all the stiffness of a wet noodle) is how to make it without distortion. This problem is complicated because these large rings have to be split after manufacturing to make them ship-able, and “noodles” spring when they are split.
Over the last couple of years, Cogmatic has been working with customers who wanted lower costs than conventionally cold machined sprockets, but also needed consistent parts because they make standard sized large drums. By bringing together our experienced shop personnel and our outside vendors, Cogmatic has established a process that includes adjusting the ring as it is cut, stress relieving after cutting, and locking it down with angle iron for distortion-free shipping and in-process inspections. The results are parts provided with minimum material for lower costs, true round shapes, and no twisting over the circumference of the part.