Educate metal stamping staff on deploying servo presses

Oct 26, 2023

New materials and technologies present new challenges to stamping manufacturing. In addition, manufacturers are facing higher turnover rates. Teaching staff how to adapt to these new materials and their related manufacturing process and how to implement these procedures is critical to manufacturing success. Kerkez/iStock/Getty Images Plus

Training and process education is more critical today than ever before. Why? Two key factors in the stamping market are driving the need for training today.

First, the new materials and technologies that are becoming more prevalent today present new challenges to manufacturing. Second, manufacturers are facing higher turnover rates in the plant, especially key support staff such as operators, setup personnel, and process engineers.

Teaching staff how to adapt to these new materials and their related manufacturing process, developing processes using new technologies to work with these materials, and how to implement these procedures has become a daunting challenge. Training and support have been recognized as an element for employee retention.

The advent of the EV industry and lightweighting efforts in general have accelerated the use of next-generation materials for the automotive industry. Materials to achieve lightweighting include not only new alloys now being developed with higher strengths, such as advanced high-strength steels, but also aluminum and fiber-reinforced composites and other composites. Currently, some parts are stamped from a combination of dissimilar materials such as aluminum and magnesium.

These materials each have unique formability characteristics. Combined, they present additional formability challenges. Their use has spread to many other industries as well, such as medical, defense, aerospace, appliance, and other nonautomotive applications.

With these new materials, the key is not how to "work the material," but rather how to "work with the material." There are a few ways to do this, and this is part of the training needed.

An employee can learn to use servo technology to tackle material and forming challenges. A servo press can be used to adapt to the forming needs of a particular material or process.

In most cases, operators, setup personnel, and process engineers can adjust the press parameters to work with the material. They can change the press speed at any point in the stroke, add dwell, and adjust cam settings and coil line feed signals. These are all digitally controlled, so tweaking the press parameters to get the required part accuracy may be quick and simple.

Stamping personnel should understand how a servo press's ability to control slide velocity at any point in the stroke can allow the material to flow as needed to achieve critical tolerances.

It's useful for an employee to learn that a servo press's slide can dwell at the bottom dead center position for several seconds under tonnage, or to hold the die set closed for long periods without applying tonnage. This capability allows the material to set or bond. This can be especially useful for forming laminates using a heated platen. Other operations, such as in-die tapping and hardware insertion, benefit from this dwell capability as well.

This is the main press control screen. The default is 100% speed, but the production speed can be changed by entering any value in the controls during production. Operators can slow the press down to see when operations in the die begin and stop. Cams actuate, in-die tapping and part insertions occur, and the press can still make parts.

Recently, these servo features have been employed in processes making proprietary batteries for EVs in the automotive industry. The ability to dwell provides moderate compression of various materials. Depending on the material and application, it may be necessary to manipulate or combine press variables.

In a few cases, increasing speed during the working part of the stroke but slowing the return speed actually minimizes reverse shock when the strippers are engaged. This improves part quality.

Having the operators and setup staff change the press parameters themselves on their current applications during die tryout can help eliminate anxiety. The adjustments can be made in the controls in real time, so they can witness the effects of the changes to the part immediately. The adage "seeing is believing" has never been more accurate.

When press and other system parameter adjustments do not solve the application problem and material has been verified to be the required spec for the part (don't just trust the "tag" on the coil or data sheet), then it's time to reach out to the tooling industry experts.

Many times, the tooling itself and the tooling process need to be modified. With the new materials developed today—and what's on the board for tomorrow—continuing education and training regarding how tooling can be modified to adapt to new materials must be ongoing.

A review of a plant's total process sometimes reveals other areas that can be improved to increase system performance. Every part operation consists not only of the press, tooling, and material, but also material feeding equipment, the in-press part transferring method, additional in-die processes such as tapping and insertion, and the unloading process. The entire system needs to work together efficiently to net a good part. This might include adjusting or syncing the timing of the feed, transfer, press speed, and motion.

Most servo presses can stamp a part slowly, even as slow as 2 SPM. This makes it possible to inspect the timing of the feed, cams, and other devices to determine if they need to be tweaked to improve throughput and part quality. Personnel can do this to minimize reworking and trial-and-error troubleshooting time.

Sales brochures, advertising, and even tool shows are not substitutes for hands-on experience using servo technology with an actual die and material in die tryouts. This is significantly more effective in bridging the gap between using traditional mechanical presses and servomechanical presses.

There is no how-to reference book that covers all these new materials and processes. It's optimal for personnel to engage in actual working webinars during which experts not only analyze and review actual manufacturing problems but also give live demonstrations on servo presses, showing exactly how to program the press parameters and manipulate them to solve these problems.

Concerning the turnover of staff, the necessity to hire and train new operators and manufacturing support staff is constant and increasing. New staff will need to be trained.

Follow-up visits and training by OEM press builders and experts provide a high level of support and serve as a continuing resource as materials and technologies continue to evolve.