EDMing thin ribs is a difficult application. High-speed machining of the elec-trodes has made it possible to fabricate these electrodes from grades that are not capable of maintaining the detail in the cavity. […]
High-speed machining centers have made it possible to machine intricate detail into almost any grade of graphite, a task that would have been impossible using manual or CNC machining equipment. […]
The physical properties of each grade of graphite determine the ranking within classifications. The properties that influence performance are particle size, flexural strength and shore hardness. […]
The graphite industry is constantly striving to produce higher quality grades. Graphite materials have continued to evolve along with the other aspects of the EDM industry, […]
Graphite is the material of choice for the majority of EDM electrodes produced today in the United States. Selecting the best grade of graphite for a particular application can be difficult if the differences between graphite grades are not understood. […]
When the above summaries are applied to the acquisition of molds, it should be apparent that a hot runner system can significantly reduce initial cost, tool construction time, and operating expenses of trials, setup, cycle time, maintenance, scrap and secondary operations—and with an efficient valve gate system—no additional equipment is necessary. […]
When designing molds of multicavity layout using cold runner systems, the mold size often is increased to accommodate the runner, slides and mechanisms—and the cavity is more difficult to orientate for complex part shapes. […]
The use of a sprue bushing to directly gate into a single-cavity mold provides several advantages in the construction and operation of the mold over the cold runner type. The mold base size is only dependent on the part requirements and will use the smallest press needed. When using a cold sprue bushing, [...]
Here are some of the results from the simulation that can now be used to optimize the mold design : pressure drop, temperature change, shear rate, shear stress, runner system volume, part cooling time and clamping force estimation. […]
As previously mentioned, performing a FEA of a hot runner system is similar to running a mold flow simulation on an injection molded part. Instead of simulating the flow in the part, the flow in the hot runner system will be simulated […]