Automation for the Fabricator

Fox Valley Metal Tech in Green Bay, WI, installed a Mitsubishi River automated material processing system in 2006. Using an ethernet-connected PC control system, the system wraps a detailed tracking and reporting system around its automated material delivery and storage functions. The result is an automation system that can handle just about anything Fox Valley’s fabrication schedule can throw at it.

“We challenge the system,” said Steve Corbeille, Fox Valley’s Vice President of Operations. “We were able to put a lot of different materials on it. We had more than 140 different types of materials that we kept on the floor in inventory at all times. We didn’t put all of our material in there; we just put in the ones we used the most.”

He estimated that 90 percent of Fox Valley’s fabricating jobs flow through the River System and onto the lasers.

The lasers are two 4000-watt lasers, which are connected to the River’s 91 shelves of material. Each shelf holds up to 4,400 lbs. of 5x10-foot material, including stainless, aluminum, and mild steel, from thin-gauge up to 1-inch plate. The company puts 30 to 40 different kinds of metal across its lasers on any given day, requiring a nimble inventory system that can track down the right piece right away.

The Fox Valley installation went smoothly because the company prepared for it and asked the right questions of itself and the technology provider. As a result, Corbeille said only minor things had to be addressed, and the line was up and running from the first day. Here are some of the questions Fox Valley asked.


Question 1: Why Are We Automating?

Automation for automation’s sake isn’t a good business plan. Without the proper due diligence, an automation project can be derailed easily by overblown investment and expectations.

Fox Valley actually began seven years ago with the purchase of a Mitsubishi MSC automation system. That original investment was made because the fabricator was losing money related to scrap generated by bad material transfer practices. An ISOstudy of Fox Valley’s operation revealed that moving certain materials with a forklift, particularly stainless and aluminum, was causing scratches that resulted in rejected parts.
 
 The system was soon upgraded to the MSCIII System with River Navigation, which allowed Fox Valley to make two important changes. First, instead of having to move sheets and plates from the original wood pallets to metal skids, operators could load them directly into a storage tower, which reduced handling and damage.

Second, using the MSCIII to pick the parts up with suction and depositing them directly into laser loading bays also helped keep scratches to a minimum.

“We had a significant reduction in the rejection of material by reducing material handling up front,” Corbeille said.

 

Question 2: Are We Prepared for the Information Onslaught?

Every automation system requires software to run it. This software allows users to run a fabricating shop more efficiently.

Fox Valley takes advantage of the automation’s tracking ability. The control system, designed by Ncell Systems, Inc., not only maintains an up-to-the-minute library of material on the shelves, but it also generates reports on material usage and parts production for whatever period of time the user desires. It also can supply and track production on other fabrication machinery around the plant, even if it’s not made by Mitsubishi.

In addition, Fox Valley uses the software to track its large assortment of partial sheets, an important issue for a cut-to-order job shop and one that the management team wrestled with when it was looking for an automation system.

“What do you do with that half-sheet or that quarter-sheet?” Corbeille said. “Working with Ncell, we were able to do a relatively simple thing, which allowed us to put the remnants on top of our full sheets. And since you’re able to look at what you have in your tower, the first thing you ask is, ‘What do we have for remnants to use up first?’ They’ll burn that remnant and then cut into the full sheet.”

The shop tracks all of its remnants. After they’re de-nested post-production, the system brings the remnant around to the storage towers again. An operator then places a sheet of cardboard between the remnant and the top sheet to avoid scratching.

What if the shop generates numerous remnants of a specific material on a given day? The operator really doesn’t want to load remnants five or six high on top of a stack, which will only make for more work later when the software calls for a full sheet.

Fox Valley creates a pallet exclusively for remnants, and the software recognizes the pallet as just that. Whether the remnants are 48x48-inches or 48x60-inches, Fox Valley puts them side-by-side and pulls them down when they are needed.

The ability to track and reuse those remnants efficiently solved a longstanding problem for Fox Valley: remnants are no longer spread all over the place.


Question 3: Can the Automation Accommodate Expansion?

Sometimes it pays to be an optimist. That’s the case when investing in your first automated storage and retrieval system.

When Fox Valley purchased its MSCIII, it came standard with an eight-shelf tower, with an option to expand that to 20 shelves. Ultimately, most fabricating operations, such as Fox Valley, begin to look for more shelving. The companies realize the power of the automation as a warehousing tool and see it as a better way to organize their overall facility.

Large automated storage and retrieval systems aren’t limited to job shops with a high mix of metal fabricating orders on a daily basis. Manufacturers with limited product lines might also have need for expanded shelving.

For example, a manufacturer of silos cuts large amounts of galvanized steel in just a few different thicknesses, and it wants to use an automated material process system to feed a long line of laser machines. The eight laser-cutting machines will be doing similar cutting jobs, but the increased volume puts the manufacturer in a position where he wants as many shelves as possible.

 

Question 4: Do We Really Need Buffer Stations?
The answer is “yes.” Most definitely, yes.

Because shops often use their automation systems to support two or more lasers, the lags between retrieval time and cycle time on the lasers can create scheduling snarls. That’s why buffer stations are needed. Fox Valley’s Steve Corbeille called them “pallets-in-waiting.”

“You can actually run one gauge of material in one laser and one gauge in the other and not ever be waiting for automation to keep up with the laser,” Corbeille said. “That has been a disadvantage for some companies that have tried to do two lasers with automation, because they’re really only able to pull from one station. That might work fine for an OEM, but if you’re a job shop, you’re floating material in and out all the time.

Featured in The Fabricator.