Automation Advancements in Plastic Injection Molding

Apr 03, 2018

When OEMs partner with a contract manufacturer (CM), the CM’s capabilities effectively become an extension of the OEM’s. The increasing computerization of the molding industry has ushered in new advances in automation and robotics that continue to drive the injection molding industry forward.

This is why it’s crucial for OEMs to team up with CMs that are keeping up with the latest automation techniques and robotics technology, especially in demanding industries such as Medical Devices, Pharmaceutical, Dental and Military Defense, where quality is paramount and competition is fierce.

How Injection Molders Use Automation
Practically speaking, automation in the plastic injection molding industry takes the form of automated work cells press-side, standardized industrial robotics, and more importantly, the integration of collaborative robotics (cobots). The custom end-of-arm tooling that can be attached to any of these robots is tailored to the unique needs of the industry: grippers or vacuum cups suitable for delicate medical component handling, nippers to trim runners when a hot runner tool isn’t a viable option, soft grip fingers to pick-n-place parts into cell packaging or stacking in an open container without marking the products.

Cobots like a “Baxter”, “Sawyer”, or those from Universal Robots are becoming more commonplace at medical molding facilities, particularly for secondary operations. These force-limited robots are designed to operate safely around humans and are easy to train - two critical requirements for contract injection molders who must satisfy the production volume demands of their customers, and keep their most vital production asset, their personnel, safe.

Another tool increasingly used to automate high-volume, repetitive processes are machine vision systems, used today in many work cells to visually inspect every molded part during production. This automated inspection augments, not replaces, the inspectors and other quality operations performed by trained personnel.

What’s Driving Today’s Increasing Automation
Advances in automation continue to impact plastic injection molding, yielding benefits for both molding contract manufacturers and their OEM clients. One of the prime motivations for the increasing use of robotics and downstream automation has been increased productivity, reduced cycle times, increased part quality, and to facilitate the assembly of smaller, harder to handle components.

Collaborative robots are perfect for meeting these challenges since they can perform repetitive movements very quickly and accurately, in addition to being very reliable. For injection molders, this translates to higher production yields and improved part quality.

How Automation Advances are Impacting the Injection Molding Industry
Advances in injection molding automation have led to several benefits not just for the actual molding, but also for the associated processes:

Quicker and more consistent insert and over molding
Robots are able to place objects like metal inserts and plastic cores inside a mold in the exact same position, at the same speed, and with the same force each and every cycle.  It’s a much safer alternative to having operator hands reaching into the press between the mold, and those operators are then able to be utilized in other areas of the plant.

Work cells are perfect for combining multiple repetitive operations
Rudimentary automation like grabbing parts out of the mold, clipping runners and gates, and placing those parts on a conveyor have been used for years. The latest developments are centering around high speed cell packaging, stacking, and custom end-of-arm tooling which now include options like automated vision inspection in addition to material handling and placement.

By combining this multitasking with speed and precision, the automated work cells now found on injection molding production lines are able of consolidating several production steps (upstream and downstream) in a smaller footprint, all while running several hours a day unattended. This frees up production staff to perform the tasks that require human dexterity and expertise, like cleanroom medical device assembly or process/product validations.

CMs who invest in this technologically advanced automation can deliver consistent results to their OEM customer, even at high volume.

Increased nimbleness of injection molding manufacturers
Today’s state-of-the-art robots feature end-of-arm tooling specific to the task they need to perform: sprue pickers, vacuum cups, grippers, nippers, and sensors. By swapping out these attachments, a single robot can aid the production of many products over its lifetime and single product lines at multiple points in the process. This makes injection molding manufacturers much more nimble, helping them adjust to the fluctuating production demands of their clients.

An ideal contract manufacturing partner should have a team with robotics and automation expertise in their facility, enabling them to use the right robot for the right task, as well as handling the complicated motion control and vision system programming. Integration expertise is also a requirement, because the biggest benefits are now found in fully automated work cells at the press.

All industries are witnessing the digital & computerized transformation of manufacturing. Part of this transformation is the rapid advancement of robotics and other automation technologies utilized by injection molders to maintain large production volumes, tight part specifications, and high quality parts.  As robots become ever more powerful, affordable, and easier to use, injection molders will continue to provide advanced manufacturing methods to bring global OEMs continued world-class quality and service.