Automated Machine Tending is Key to Shop’s HMLV Production Strategy
At Precinov, low-volume/high-mix job production requires fast setups and changeovers to maximize efficiency. While the Levis, Quebec, precision machine shop considered automation as a way to achieve those production goals, it discovered that implementing it, depending on the type, can be time consuming and complicated. It was at that point the shop decided to take an innovative approach to keep pace with production demands and incorporated standalone automated machine tending cells.
Precinov specializes in the manufacture of small, complex high precision parts, mainly for high technology customers in the opto-mechanics, robotics, medical, electronics, and energy industries. It also provides integrated services for mass production of parts, prototyping and computer-aided mechanical design. Job lot sizes can vary from a handful of parts to sometimes 1,000 pieces, machined mostly from aluminum but also from stainless steels, plastics, exotic materials and copper as well.
Precinov operates a two-tiered business, working both as job shop manufacturing parts to order while also building parts for inventory to enable immediate fulfillment of orders from repeat customers. The shop operates 24 hours a day and on weekends. Each day’s first shift is manned, while evening and overnight shifts run lights-out thanks to its machine tending automation.
During the first shift, shop personnel run small jobs that wouldn’t benefit from automation while they also set up jobs to be run untended on the second and overnight shifts. Because the shop does not produce long runs of identical parts, Precinov owner Mathieu DeBlois looked for an automation system that was flexible and quick to set up. As a result, eight of the shop’s 12 machine tools have automated systems and five use PartNR systems engineered by Mirabel, Quebec, automation provider Waybo, a company that specializes in the design and implementation of industrial automation systems.
Citing the ongoing shortage of experienced shop personnel, DeBlois said, “We don’t want to waste our skilled individuals using them to load and unload a machine. We need their brains for setting up machines.”
Precinov’s Waybo machine-tending cells incorporate robots from KUKA Robotics. The shop has five KUKA robots, including three AGILUS units with 10 kg maximum payload capacity, a KR20 CYBERTECH robot with 23.9 kg maximum payload and 1813 mm reach, and a KR22 CYBERTECH with up to 27.3 kg maximum payload and 1612 mm reach. The six-axis AGILUS robots are designed for high working speeds and precision. CYBERTECH robots feature outstanding power density and a large range of models.
Waybo’s pre-engineered turnkey PartNR machine tending cells are designed for low volume, high mix applications. Compact (1m x 1.28m x 2.2m) and easy to program, the cells have manipulator systems and adaptive robotic grippers that enable Precinov to flip a part and machine all sides of it without removing it from the machine tool.
“Even if it’s on a multitasking machine or a lathe, 3-, 4-, or 5-axis machines, we flip the parts,” DeBlois said. “When the part is done, we ship it to the customer complete and without needing secondary operations. Flipping a part has to be accurate to maintain tolerances, and the KUKA robots are very precise. Any robot can do a first operation on a blank of raw material, but flipping the part and remaining precise is a different challenge.”
Each machining cell in the shop has its own automation setup and is independent of the other cells. Precinov did not pursue the idea of using one robot to service several machines because taking a machine out of operation for part changeover, maintenance or breakdown would affect the entire system.
“By using a robot on each machine, it is easier for planning, and Precinov can run whatever it wants, quickly,” said Waybo President Jean-Sébastien Neveu. “The shop employs 25 people, and the Waybo automation enables seven operators to keep the shop’s 12 machines working 24/7.”
KUKA robots are “easy to understand and program,” DeBlois added. “The robot does not add to setup time; the longest part of the setup is not the robot, it’s the CNC machine.” To further expedite programming, the robots extract information from the shop’s CAM programming system regarding part sizes, vises, fixtures or other obstructions in the machine.
The most important advantage of using multiple robots is ease of setup and ability to respond quickly to changing customer demands. Using the same robots throughout the shop simplifies employee training and shifting staff from machine to machine.
“We are working on making everything the same,” DeBlois said. Precinov plans to expand its utilization of machining and programming data to help the shop further improve its production planning and machine maintenance. With the majority of its work occurring untended, the biggest challenge is assuring process security when the shop is operating lights out. The simplicity and reliability of the KUKA robots and WAYBO machine tending cells support that completely untended operation.
About the Author: Phillip Peloso
