(Munich, Orlando, March 23, 2015) The newly developed APC (Adaptive Process Control) machine function from KraussMaffei immediately compensates for fluctuations in the injection molding manufacturing process. The result is consistently high component quality. Early in the year KraussMaffei successfully installed the first APC functions among customers in the USA. Visitors can become convinced of the advantages of the APC function live at the KraussMaffei trade show booth (West Hall Level 2 Hall A, Booth W903).
Less scrap – more productivity
“The revolutionary aspect of APC is that component quality serves as the definitive control variable. Since the APC function acts as correction during each cycle, previously unforeseen possibilities for robust and more efficient injection molding are now open,” says Dr. Reinhard Schiffers, Head of Machine Technology at KraussMaffei. The APC function developed and patented by KraussMaffei adjusts the changeover point and the holding pressure profile in each cycle to the current melt viscosity and current flow resistance in the mold. This makes it possible to compensate for deviations in the same shot. This leads to significantly lower fluctuations in article weights. In this way, fluctuations in the manufacturing process triggered by external factors such as changing temperatures, climate conditions or batches can reliably be compensated for.
For example, the American plastics processor Woco IPS (in Waco, Texas) was amazed by the robustness of the injection molding process through APC when the new machine function was installed. "In Texas we're subjected to extreme climate fluctuations during production. We are convinced that by using APC, we'll be able to compensate for these fluctuations reliably and ensure constantly high product quality," explains Alexander Wein, Global Project Manager Railway at Woco. The location in Texas acts as a supplier primarily for the railway and transport industry and is currently applying for ISO certification for the automotive industry. "The APC function will surely provide us with more support in implementing the high quality required here," Wein adds.
Faster restarting and easy retrofitting
Along with improvements to general process stability during ongoing production, APC also provides advantages when restarting production after machine downtime. “The Adaptive Process Control system precisely detects to what extent the material viscosity has changed during machine downtime. The production of reject parts is avoided thanks to the specific adaptation of the changeover point and the holding pressure profile,” says Dr. Schiffers. Even changes in the machine, such as signs of wear on the screw and barrel or the closing behavior of the nonreturn valve, which may lead to irregularities in the plasticizing and injection process, can be compensated for via APC.
Uniform processes, material savings and faster restarting were also the arguments that sold Intralox (in Harahan, Lousiana) on APC. "We have about 600 different molds in use. Per day we have about 40 mold changes. The APC function yields enormous savings potential for us," explains Tom Moore, Technical Project Manager at Intralox. In addition to this, the technical project manager praises the easy installation of APC: "The KraussMaffei AX 130-750 injection molding machine was equipped with the APC function in a completely straightforward and intuitive manner. Ongoing production was not impeded in any way." The APC function is offered for all machines, both hydraulic and electric, from KraussMaffei and can also be easily retrofitted in existing machines (MC5 and MC6 control systems).
Increasing the portion of recycled material
Injection molding machines with an APC function also enable reliable processing of high quantities of recyclate, which often cause fluctuations in viscosity. "Large quantities of recyclates are processed in the USA, particularly in the packaging and logistics industry. Using the APC function yields enormous potential," according to Paul Caprio, President of the KraussMaffei Corporation in the USA. Using the APC function can prevent fluctuations in component weight within adjustable limits due to a change in material viscosity. Even if the recyclate quantity increases, the component quality remains consistent.
As consistent as cruise control
In a figurative sense, APC operates the same way as cruise control for vehicles. As is well known, cruise control systems automatically control the supply of fuel to the engine so that the vehicle does not drop below or exceed a speed defined by the driver, even in changing road and wind conditions. Similarly, APC is able to keep the shot weight specified by the mold setter consistent during ongoing production if, for example, the material viscosity changes due to outside factors. However, cruise control does not replace the driver; similarly APC cannot replace the machine setter. Only after the mold setter has configured the parameters for a high-quality part is APC activated, stabilizing the process and taking part of the workload from the operator.