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Productivity-Improving Obstacles Fall Like Dominos
“Our new controls (Automator II units from Cieco Inc., Clinton, PA) have done their job for us, and more,” says Clairon tooling manager John Butler, “and we’ve seen a domino affect throughout the plant. We continue to raise our performance standards, and adoption of new press controls is what allows that to happen.”
On the Upturn, FinallyClairon Metals operates a 114,000-sq.-ft. shop in Covington, GA, with 27 presses from 35 to 1100 tons. “We’re on the upturn now, finally,” says Butler, “happy to have been able to hire back several employees as our business has recovered from a tough 2009. We’re seeing a lot of takeover work from stampers less fortunate.
“But, I will say that we took steps well before the slowdown that allowed us to survive while others did not,” Butler adds. Those steps include careful monitoring and tracking of press downtime and production efficiency, and “getting lean before we had to,” Butler says. “If we had not, for example, performed all of the quick-die-change Kaizen events we did in 2007, improved production efficiency from around 50 percent to 80 percent today, and cut our downtime from 150 hr./day (operator downtime throughout the plant due to idle equipment) to just 25 hr./day, we would not be here either.”Clairon, which supplies stampings and value-added assemblies to the automotive, ATV, HVAC, and metal-furniture industries, has evolved into a short-run high-mix operation to minimize inventory buildup and meet customer just-in-time supply demands. It runs primarily coil stock of cold- and hot-rolled mild and high-strength low-alloy steels, as well as plenty of 300- and 400-series stainless used for ATV exhaust components and other parts.
Its sweet spot, says Butler, is sheet 0.10-0.125 in. thick, although its recently picked up a lot of ¼-in. work for automotive and truck brackets and frames. “We run two weeks’ worth of inventory max for most of our parts,” Butler says. “So, if our typical annual volume for a part is 30,000 pieces, we’ll set up a press to run 1000 parts and place them in inventory—that’s maybe a 30-min. run time on one of our coil-fed presses. The end result is that we’re forced to perform numerous die changes throughout the plant, all day long.”Quick Changovers Get the Ball Rolling
Making dozens of daily die changes can strangle a shop’s throughput unless efficiency is optimized, and back in 2006 the plant’s pressroom struggled to attain a production efficiency above 50 percent. Changeovers took as long as 8 hr. as press operators waited |
| A Clairon Metals press operator tends to one of 10 new press controls installed among the firm’s coil-fed progressive-die presses. The new controls not only manage the firm’s aggressive die-protection program, but also direct all of the action in and around each press cell, including pulse-spraying of lubricant, operation of pick-and-place part-handling automation devices, pulsed air ejection to move parts off of dies, and shaker-conveyor action. |
“We changed the procedure and now allow operators to begin to run parts as soon as dies are changed and a line’s ready to run,” says Butler, adding that the firm’s typical die change now takes just 20-30 min.. “Operators visually inspect and approve the first parts off of a new setup, and we run parts in containment until quality can come out to the floor and check the parts.”
Among the steps taken to quicken die changes: the shop now assigns a primary and secondary press for each tool, and stages the tools near that primary press; and, it modified all of its tools to accept a standard locating method in the press.“We machined a slot down the center of each bolster and keyed the dies to locate them in the slot,” says Butler, who was the plant’s die-maintenance manager back in 2006-2007. “We also purchased new quarter-turn quick-acting clamps.”
Getting Ahead of the Maintenance Curve“Slashing die-change times from hours to just minutes made a huge impact on scheduling and lead times, and simplified our ability to manage the visual manufacturing process, continues Butler. “Also, back at that time we could never get ahead from a die-maintenance standpoint. We’d spend $15,000 or more per month repairing broken dies, and experience as many as 20 mishits or crashes each month.”
Butler and his team had installed a die-protection program at the time, but he feels they had taken it as far as they could have with their current press
Throughout 2006, Butler and his team retrofitted 10 of its highest-output coil-fed presses with the Cieco units, upgrading two presses every six weeks to avoid interfering with production. “We went through a learning curve with Cieco’s technicians,” Butler says, “and working together we identified several ways to customize the controls to best-fit our needs. For example, they switched out the capacitive-type monitors on the controls with resistive monitors, to better resist the rigors of the pressroom.”
One of Clairon Metals’ fully sensored dies ready for action—parts eject at the top of each stroke onto a mechanical unloader. The die includes short-feed sensing, ejection cylinders are monitored at each of the stroke. Form punches are sensored to ensure part ejection, and a through-beam sensor covers the lower die to catch parts if they fall into the die
Other custom upgrades at the time (which have now become standard features on the controls) include an auto-logout feature so that if no one accesses a controller within a 5-min. timeframe, the control locks out access to prevent someone from changing any settings on the control. “And, we asked for the ability to set 250 individual passwords for access to the control,” says Butler, “rather than the standard 50 passwords.”
Butler quickly went to work taking advantage of the new-found die sensor capacity, using automation control inputs to direct all of the action in and around each press cell, including:• Pulse-spraying of lubricant;
• Operation of pick-and-place part-handling automation devices
Clairon’s in-die sensing program, ramped up since it installed new controls on its 10 hardest-working presses, slashed die-repair costs from $69,000 in 2008 to $28,000 in 2009, and this the firm expects that figure to drop all the way to under $5000
“Most of our dies have at least five or six sensors,” he says. “Die crashes are way down, to a maximum of one or two per month, a huge improvement from the double-digit monthly die crashes the firm once endures. “And now when a press stops, everything else stops as well,” says Butler. “Not so long ago we were averaging 40 man-hr./day for die maintenance; that’s now down to just 5 hr./day.”
Save a Press—Monitor TonnageThe controls’ tonnage-monitoring capabilities are in full display at Clairon Metals, too. Tracking tonnage has allowed the firm to relocate several tools to different presses to avoid impending press damage.
“It’s amazing how one relatively simple and affordable change like new press controls can change everything you do in your facility,” says Butler. “With tonnage monitoring, we’ve been able to treat any press-overload cases like corrective actions. Doing so, we’ve avoided any ram-adjustment issues and failures in areas such as tie rods and counterbalance rods. We also use the data from the monitors to take a proactive approach to scheduling preventive-maintenance activities, such as tool sharpening
The domino effect from Clairon Metal’s ongoing improvements is best illustrated by this graph of production efficiency, which has climbed from barely 50 percent in 2006 to near 80 percent today.
And the dominos keep falling… MF
See also: Cieco, Inc.
Related Enterprise Zones: Sensing/Electronics, Tool & Die
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