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AGR, KHS team for control system

Issue: March 2018

Agr International has expanded the capabilities of its established Process Pilot automated blow molder control system by introducing Individual Mold Control (IMC) to manage bottle thickness during PET bottle production on the individual mold level.

Agr’s patented Process Pilot system has been on the market for several years, with more than 400 installations worldwide. The Process Pilot system manages the blow molding machine based on direct measurements on every bottle produced. By controlling the blow molder based on direct feedback from bottle measurements rather than just machine performance indicators, Agr said its system helps to ensure final product quality and performance, regardless of environmental, machine or material variations that occur during production.

Even with the most advanced PET bottle blow molding system, variations occur in bottle material distribution from mold to mold, and each mold performs slightly differently, Agr said. The resulting variations can result in inconsistent performance from bottles made during the same production run, leading to potential downstream problems.

The company said the latest addition of IMC to the Process Pilot product group resulted from a collaborative effort between Agr and KHS GmbH, a German maker of filling and packaging equipment for the beverage, food and non-food sectors.

IMC gives users the ability to optimize the blow molding process by controlling the parameters for each individual mold station, in addition to the global parameters set for all molds. “This makes it possible to proactively manage the process down to the individual mold level to finely control material distribution and minimize mold-to-mold variation,” the firm said in a press release.

Process Pilot captures high-precision thickness distribution measurements on every bottle, Agr said. Typically, the Process Pilot system manages material distribution to a base-line thickness established on an overall average of all mold stations by controlling the oven parameters and first pressure, as well as start time. 

The development of IMC “takes distribution management to a new level by identifying the distribution variance from mold to mold. Using an advanced control algorithm, the IMC option provides the means to reduce individual mold station variability by proactively adjusting the pre-blow start time of each mold station through individual mold offsets,” the company said.

Doing so makes it possible to achieve an overall tighter distribution model over the entire mold set, much closer to the base line than can be provided using the global approach.

At September’s PETnology conference, held during Drinktec 2017 in Munich, Agr COO Robert Cowden teamed with Frank Haesendonckx, director of KHS sales and technology, to give a joint presentation about improving beverage line productivity via automated process control.

Haesendonckx detailed the joint effort between Agr and KHS to implement IMC on the KHS-series IV and V blow molding machines. He noted how the process not only provides the means to quickly identify and correct performance issues on an individual mold station, but also captures valuable mold-performance data that can be used to determine the optimal time to perform system maintenance, all while maximizing productivity.

According to Agr, other benefits include:
• Reduced production variation;
• Improved downstream performance;
• And increased opportunities for further lightweighting.

When lightweighting, for example, rigorous adherence to the material distribution parameters for each bottle type is key to weight reduction. It’s vital to keep the precise amount of material where it needs to be during the molding process; otherwise, you cannot effectively lower the weight. And the less material you use, the more challenging that task becomes. Greater control of material distribution, therefore, leads to greater opportunities to lightweight.

Process Pilot with the IMC option is compatible with rotary stretch blow molding systems that incorporate independent mold-station management. The IMC option is available for KHS-series IV blow molders, and a retrofit version is available for Process Pilot systems already in operation.

In his presentation, Cowden pointed out that whether process variability is mostly due to environmental conditions, operator skills or manufacturing practices, all have an impact on bottle production and the ability to operate at optimum levels.

“Managing variation in the blowing operation is the key to optimizing beverage line productivity, and the most efficient way to accomplish this is through automated blow molder control,” Cowden said.

For more information

Agr International Inc.,
Butler, Pa., 724-482-2163, www.agrintl.com

KHS USA Inc.,
Waukesha, Wis., 262-797-7200, www.khs.com