June 2007 Edition

Waterjet

Waterjet Helps Place a Manufacturer’s Quality a Cut Above

When an auto interior maker found its equipment wasn’t making the cut, it turned to a waterjet that could handle it

It’s a story familiar to almost anyone creating parts: A new product line means expansion and increased profits, but brings higher production volume, increased productivity levels, and closer tolerances. These were the demands facing the Madisonville, KY, plant of Lear Corp., Southfield, MI. Lear Madisonville supplies automobile interior systems such as seats, instrument and cockpit panels, doors and trims, overhead and flooring, and acoustic materials.

A new product launch meant ratcheting-up production. The company planned to use an existing waterjet system for new business, but in the middle of a launch, discovered the system could not handle the requirements. Lear needed a system that reduced cycle time, met production and quality demands, and could be installed and running within a 10 week window of opportunity.

Time to Improve
Lear Madisonville’s existing robotic cutting system came up short for the new project. The system cycle time took too long and the robots’ reach and repeatability made it impossible to meet new tolerances.

The company contacted KMT Robotic Solutions, Inc., formerly Robotic Production Technology, Auburn Hills, MI, for a solution based on an KMT Robotic Solutions robotic system already working in the plant. KMT Robotic worked with Lear Madisonville to engineer, design, deliver, and install a turnkey waterjet cutting system. KMT Robotic helped program the system and Lear had the system in production 10 days after delivery and installation.

The new KMT Robotic JetTool waterjet cutting system included four AccuTrim WJ-44 robots in an open-style gantry with a fixture table, waterjet intensifier, and a JetVac system. The JetVac vacuum holds parts during cutting and removes waste particles and water. It improved repeatability and provided dryer parts. The JetVac removed the need for operator part placement.

The system also featured Accuracy Enhancement Tools and JetWare software. The tools included TCPMate software to set the tool center point of each robot, CellFinder to correct fixture placement variances, and CalMate to automatically master the robot without the use of a mastering fixture.

With a few dimensional inputs, JetWare produces common geometric shapes and creates a library of custom shapes. It also extends functionality to basic programming features.

No More 48-Hour Shifts
Lear Madisonville’s old system had poor reliability and capability. The automation team spent so much time replacing components and making adjustments that sometimes they had to pull 48 hour shifts to keep the system running.

Where the other system required daily adjustments, Lear process technicians didn’t need to make any adjustments to the new system for two weeks after the initial setup.

The KMT Robotic JetTool system reduced cycle time by 75 percent, enabling the waterjet cutting process to keep up with the molding process.

The system eliminated workpiece storage so Lear didn’t have as many deformations from storing and stacking the headliners as it did in the past. Lear Madisonville attained better process flow since its products moved from final assembly directly to shipping racks for customer delivery.

One product’s cycle time went from 89 seconds to 23 seconds. With such a cycle-time reduction, Lear Madisonville sought larger-volume customers and customers who require parts with more stringent quality.

Almost 87 Hours Per Year Cut from Downtime
KMT Robotic’s Accuracy Tools also contributed to saving time. Lear estimated that JetWare saved the plant 15 to 20 minutes of downtime per day. CellFinder saved the company an hour of downtime each time a fixture was changed. TCPMate saved at least 30 minutes per day.

The KMT Robotic JetWare software provides software programming features to create circles, squares, and other shapes. It develops the program for the user and removes operator intervention. In the past, if a Lear Madisonville operator added a circle and a day later, the diameter was found to be too large by 1mm, as much as five hours could be spent fine-tuning the circles. JetWare has an offset option which sets the diameter automatically. Process techs can make adjustments to the robot much easier and in much less time than in the past.

The system’s increased capacity and lack of downtime allowed the company to reduce weekend and overtime work and provide a return on investment of less than one year.

Since the time spent making adjustments was reduced, one process technician per shift was reassigned to maintenance. The system helps Lear Madisonville work smarter and more efficiently and reduced the need to add maintenance department staff.

The JetTool System and Accuracy Enhancement Tools helped the company decrease the error levels for all of its customers, and reduced one customer’s rate to zero. The system also provided a means to track which fixture had been used to cut a specific headliner. By using this process, quality issues could be tracked back to their source.

Lear Madisonville uses KMT Robotic’s programming expertise on a regular basis. The robotic company’s programmers often assist with new product launches so Lear engineers and process technicians can focus on other areas of the launch. Lear Madisonville now has two programmers versus four.

KMT Robotic Solutions www.rsleads.com/706mn-209

What do you think?
Will the information in this article increase efficiency or save time, money, or effort? Let us know by e-mail from our website at www.ModernApplicationsNews.com or e-mail the editor at pnofel@nelsonpub.com.