Sponsored By

April 1, 2003

4 Min Read
Editorial: Automation revisited

MSnyder.jpgA story making the rounds has it that the factory of the future will be so highly automated that it will be monitored by only one person and one dog. The dog?s duty will be to guard the machines to keep the person from messing with the controls. The person?s duty is to feed the dog.

I first heard the story some years ago from Joel Kiester, a Colorado molder, since retired, with a successful specialty of molding excruciatingly tiny parts. He did take his dog to work, as I am a witness. The dog, however, was a mild-mannered dachshund that seemed unlikely to protect anything, with the possible exception of its own kibble.

Canines aside, attention toward automation in plastics processing has intensified as processors face increased international competition. Robotic automation has mostly been associated with handling machinery output, whether it be molded parts, extruded pipe, blowmolded bottles, or thermoformed containers.

To some extent, automated systems are seen in other roles, such as loading inserts before parts are injection molded, or removing sprues and runners to be ground up for recycling or disposal. Primary machinery and its attendant auxiliary equipment is more than ever highly automatic in operation, and controlled by microprocessors, programmable logic controls, or personal computers.

Still, in an era when processors can leave no stone unturned in the search for competitive advantage, one aspect of potential automation tends to be neglected, namely material handling prior to processing.

Pellets or powders can be handled automatically from the moment they arrive on a processor?s site by railcar or truck. There are already places where this is done, of course. But in an industry looking for every possible competitive edge, there is a lot of unrealized potential in automating material handling. Can any processor expect to remain competitive by delivering material to the machine via a guy on a ladder with a bucket? That practice is inefficient and dangerous. Just the thought of it makes us cringe.

Two equipment suppliers recently reminded us that materials-handling automation can and should be done. (Neither asked to be mentioned in this column, nor knew until after the fact that they would be.)

Comet Automation Systems (Dayton, OH) recently installed a turnkey, automated material handling system for a California-based Tier 2 supplier of automotive parts. The installation consisted of four silos, surge bins, central dryers, four hot air dryers, 10 central weigh blenders, central loaders for blenders, central loaders for molding machines, a regrind reclaim system, Allen-Bradley control, and a custom mezzanine. By the processor?s calculations, they reduced labor requirements by the equivalent of three workers, and saved all of the usual personnel-related costs.

Mould-tek (Toronto, ON) points out that controlling the flow of ingredients in plastics processing has been evolving with the development of electronic technology. The final objective is complete automation of the process.

Historically, bulk handling systems were rudimentary, the objective being to get the materials into the machines with acceptable control and accuracy. Wastage was taken for granted as was the need for on-the-floor operation and control that meant high labor content.

One challenge is to make the machine feeding system accurate. Materials are too expensive to waste through inaccurate loading. This involves the blender. Blender producers use different approaches to measuring the materials input into the mixing chamber, but all strive for accuracy.

Memory chips and circuits became essential as blenders began to feed materials for a growing variety of parts processed in the same machine. Now, menus allow operators to select ingredients and relative portions. These controls include touch-screen designs and multiple menus. Two-way communication between PC and blender allows the operator to change menus in the on-site control. It also permits menu changes at the blender site to be communicated to PC memory. Data can be accumulated for immediate or future study.

Materials handling can go a long way towards automation, but processors have to take the first step. It?s time to get rid of the ladders and buckets and move forward, for the sake of both present and future success.

Merle R. Snyder

Sign up for the PlasticsToday NewsFeed newsletter.

You May Also Like