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Job Shop Technology Writing Samples
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These samples were written by JMB Communications for Job Shop Technology magazine, and are copyright 2002, Edwards Publishing. Reprinted with permission. To learn more about Job Shop Technology, visit them.
Fountainhead Cryogenic Processing:
The Chilling Story of Brute Strength and Durability Although Fountainhead Cryogenic Processing President Bill DeFelice is very passionate about the value of his technology, he often receives phone calls from would-be users who just don't understand what it's all about.
"A lot of people who hear about cryogenic parts processing conclude that it's a really good idea," he says, "but then they go out and buy a glorified chest freezer and expect success. It doesn't work that way. You have to know metallurgy and be conversant with other aspects of materials research, you must do the process correctly, and you must have knowledge about what specifically it is that you're trying to accomplish."
What Are You Trying To Accomplish?
Ask Mr. DeFelice what exactly this cryogenic treatment process is, what it does, and how it works, and you acquire a real education about cryogenic science - a lesson which is easily leveraged in day-to-day materials processing.
Although cryogenics can be used with many materials, it's metal that sees a truly high degree of cryogenic treatment.
As those who work with metal are well aware, when steel is first made it is in a state called austenite, or a specific arrangement of carbon and iron atoms within a crystalline structure. "Austenite is a soft phase," Mr. DeFelice explains. "Materials in the austenite phase are very easy to machine using conventional tooling - in fact, gears and other tooling are often rough-machined as austenite, after which they're heat treated."
Depending on the chemical composition of and on the properties needed in the final product, gears and tooling may be heated to 1600º F or higher, Mr. DeFelice says. At this temperature the atoms that make up the austenitic crystalline structure shift and become martensite, which is very hard and brittle. A good analogy regarding the effect of this shift of atoms is coal and diamonds, he says, both of which are made solely of carbon. "In coal, as most people know," Mr. DeFelice says, "the carbon atoms are not arranged which makes it easy to take them away by wear or some other reaction like heat. In a diamond, the carbon atoms have a very different bonding arrangement, making them the hardest substance known. Diamonds are formed through heat and pressure and time -- a lot of it."
After being heat treated to martensite, tools and gears are quenched, or cooled very quickly, in air, water, or oil. "If you let the steel cool on its own, the martensite would just transform back into austenite, so you have to quench the product to seal in those changes" DeFelice notes. Since steel being quenched cools from the outside in, it doesn't cool at the same rate; the outside remains mostly martensite and the inside is progressively more austenitic. Some warping occurs during quenching, so the quenched tool must be ground to final dimensions -- taking away the outermost martensite layer. The tool is then tempered at 300º to 400º F to add strength to the martensite.
Enter Cryogenics
That's when cryogenic processing begins. "Tools or gears or other products can be cryogenically processed days, months, or years after heat-treating. There's no need for a cryogenic processing plant to be co-located with a heat-treating plant. The cryogenic treatment takes the austenite that did not convert into martensite during heat treating and converts it into martensite while also precipitating very fine carbide particles out of the crystalline structure which then migrate into the grain boundaries. Under cryogenics, steel is slowly cooled to -310º F. and is cold-soaked at that temperature for at least 20 hours.
"As a consequence of cryogenic processing, the entire matrix holds together much better. Perhaps most important, the carbide particles are extremely wear resistant," Mr. DeFelice says.
In the final cryogenically treated tool or gear or other part or device, there are two important qualities, he claims. "The first, dimensional stability, comes from not having two phases of metal existing side by side. The second quality is wear resistance," he continues, "which comes from the martensite and carbide particles."
But Mr. DeFelice admonishes, "The whole process is very dependent on how the heat treatment was done. If the heat treatment made the part into a piece of scrap, then cryogenically treating it will just make it a cold piece of scrap. The process must be done correctly. If it is, the product will be exceptional."
Perfecting Cryogenic Processing
While working for a large manufacturer for 15 years, Bill DeFelice - who is an engineer in addition to being Fountainhead Cryogenic Processing president -- had gained a working knowledge of tooling. Because his company works with a wide spectrum of businesses (see Cool Applications, below) and because he's been researching cryogenic metallurgy and the wider spectrum of cryogenic processing for seven years, Mr. DeFelice is well aware of which materials respond well to "cryo" treatment and which don't.
"To 'cryo' correctly," he says, "you must use the correct processor correctly. Our cryo chamber is a patented double-walled, stainless steel, vacuum insulated cylindrical device; the vacuum between the inner and outer walls is the perfect insulator."
Parts subjected to 'cryo' in Fountainhead's processor see less than a five-degree temperature gradient, which Mr. DeFelice says is quite important. "The narrow temperature gradient," he says, "ensures more uniform target cooling. Unlike our cylindrical processor, competitive rectangular processors can't keep temperatures as uniform. The result of uniform cooling is greater quality and consistency in finished products."
Fountainhead's process is dry - the payload is never subjected to the liquid nitrogen coolant, which instead is used in conjunction with a heat exchanger to cool the air around the payload, usually to about -300º F.
"The whole cryogenic process," he explains, "boils down to a specific slow rate of cooling followed by a long soak period followed by a mild temper (300º F) for some items. Our processors cover that full range, from -300º F. to +300º F.
"Some cryogenic processing companies may try to tell prospective users that the next generation in cryogenic processing is what they call 'thermal cycling,' which is numerous periods of cooling followed by heating. However, all of the research that has been conducted into cryogenic processing shows that the critical component is time at temperature -- the longer the process stays at cryogenic temperatures, the more complete the transformation from austenitic to martensitic. The longer the soak, the better formed the eta-carbides, in those materials with carbide-forming elements. Those who advocate thermal cycling say they subject parts to the same degree of cryogenic cooling as we do, but it is not all in one shot. Cycling is advantageous only when the cryogenic treatment is used for dimensional stabilization."
In fact, Fountainhead uses cycling for products requiring dimensional stabilization.
Advantages of Cryogenics
Mr. DeFelice suggests that the most accurate way to regard cryogenic processing is as a continuation of the heat treating process. But a bad heat treatment can't be fixed with cryogenics.
Advantages of cryogenics include:
--Dimensional stability. Less warpage of the final product helps ensure adherence to specs/tolerances.
--Product durability. Parts need only be cryogenically processed once, since the process lasts for the life of the part. Cryogenic treatment extends the service life of tools, dies, and steel parts such as springs, wheels, shafts, bearings, gears, sprockets, and valve components. Parts which have been cryogenically treated exhibit increased toughness, wear resistance, and dimensional stability.
--Durability of coatings. "Users of coated tooling are finding that coatings have a greater affinity for martensite over austenite," he notes. "If you subject coated metal to cryogenics," he explains, "the conversion of retained austenite to martensite in the base metal while down at temperature will enhance the bond of the coating to the base material. Some customers tell us that it takes twice as long for the coating to wear off cryogenically treated tooling as non-cryo-treated cooling."
--More effective polishing. After cryogenic processing, micro cracks and voids are filled in, Mr. DeFelice says. The advantage is noticed when the part needs to be polished - less effort is required to produce the same surface finish compared with non cryo-treated parts.
Disadvantages of Cryogenics
To complete cryogenic processing effectively takes time - upwards of 30 to 50 hours, and it cannot be converted to a continuous process. It can't extend the wear life of most natural materials like wood, natural rubber, and leather. It can't make products stronger but it can and does increase wear resistance significantly.
Sometimes that very wear resistance has unintended consequences, Mr. DeFelice relates. "The garment industry customer of another cryotreater treated its sewing needles to improve wear resistance. Ultimately they had to stop using the needles because they were 'destroying their sewing machines.' The sewing machines had a platen under the deck on either side of the needle. Normally, if a needle became misaligned, it hit the platen and spanned, stopping the machine. With cryogenically treated needles, misaligned needles pierced the platens and became stuck or worse, kept going. Downtime increased because the company's maintenance department had to replace needle-embedded platens."
Real-World Applications of Cryogenic Processing
Most companies are proud of their processes, of their product quality, and of their commitment to their customers. "Our customers don't usually look to cryogenic processing as a solution to a particular problem," Bill DeFelice admits, "but after they have used a cryo-treated tool, their perspective changes and they come to regard non-cryo treated tools as a problem."
Here are three examples of cryogenic processing used by a tooling manufacturer, a maker of flat-screen TV displays, and a paper company:
A tooling manufacturer was required by his customer to make three mandrels. A bar about ten inches long and ¼ inch in diameter was to be welded onto the end of a standard tool holder. The run-out on the bar was to be .0002".
During two attempts to manufacture the mandrels, the toolmaker started grinding the bar to final dimensions but the heat generated by grinding warped the bar, throwing it out of tolerance. On the third try, he brought the materials to Fountainhead prior to grinding. "We treated them and after the final grind, they stayed where they were supposed to. That's how the 'dimensional stability' advantage of cryogenic processing works."
A manufacturer of flat screen TVs made assembly line adjustments to sets by inserting a non-metallic hex-shaped driver into an adjustment screw. Each driver is turned an amount determined by a readout at the station. The drivers had to be non-metallic since they were used with induction coils, and any metal brought into close proximity would bias the reading. After about 100 insertions, the corners of the drivers wore, and the driver had too much play to be useful. "An engineer brought us 10 of their standard epoxy drivers, which we treated," Mr. DeFelice relates. The drivers were five to six inches long and the hex end was about ¼" flat-to-flat. "A week later," he recounts, "the engineer told us that one of the drivers was in a test stand. At that point, it had lasted for 600 insertions but it had worn out three screw heads. Ultimately, the driver lasted over 1000 insertions, ten times as many as the non-treated drivers."
A chipper in a paper mill has 15 blades which are 34" long, 6 5/8" wide, and 3/8" thick. A single bevel edge on one side does the cutting. "When frozen hardwood was being processed, the blades had to be changed twice per shift, which required a lot of manpower and resulted in downtime," Mr. DeFelice says. "It took three men two hours to change one set of blades. The mill had Fountainhead treat one set of blades, then they put them on their system. After they completed the evaluation, they told us their annual savings from treating only that type of blade would be $200,000 in recovered production time and reduced need for new blades. They are evaluating other uses which if adopted, will save them millions of dollars a year because they will have more uptime and need far fewer replacement parts for those processes. They found that their concept of the standard life expectancy for a part could be turned on its ear by cryogenic processing."
Cool Applications . . .
Cryogenic processing can be effective wherever strength and a high degree of durability are essential. Fountainhead's business reflects this, with applications in the industrial, food processing, motor sports, government, and miscellaneous categories. In the industrial sector are customers such as machine shops and tool and die shops which make end mills, drill bits, cold saws, carbide inserts, slitter wheels, chipper knives, copper spot weld electrodes, hammer mills, and wear plates. Fountainhead's industrial customers include Ingersoll-Rand, which makes construction equipment; P. H. Glatfelter, a paper company; Leonhardt Manufacturing, a Harley-Davidson subcontractor; Readco Manufacturing, a maker of industrial mixers; Armstrong World Industries, the global maker of ceiling and floor tiles; and Babcock Borsig, which both installs and retrofits cogeneration plants.
Food processing applications include food cutting knives and blades, maintenance tooling such as bits, files, and saws, and electrical transformers, AC and DC motors, and circuit boards. Customers include Hershey Foods, Martin's Potato Chips, Wise Snack Foods, Herr's Snacks, R. M. Palmer (the chocolate bunny people), and Verdelli Farms.
Cryogenically treated parts in motor sports range from engine blocks to piston rings to brake rotors, for professional racers, go-kart enthusiasts, and weekend racers.
Government applications include cryogenically treated gun barrels, brake parts for USPS vehicles, and potential work for Amtrak.
"Miscellaneous" applications includes a far wider range of products than most people would imagine, from golf balls to women's pantyhose to golf club parts, chainsaw and lawn mower blades, speaker wire, aerospace castings and components, automotive components, and much more.
* * *
Diverse Contract Manufacturer Elrae Reinvents Itself, Focuses On
Leveraging Technological Prowess To Solve Customer Problems For a while, it seemed that Elrae Industries, Inc., had too much of a good thing.
The Alden, New York-based producer of stamped and roll-formed metal components and custom assemblies had done well since its founding in the 1940s, but during the 90s it experienced growth that, in the end, proved painful.
By the late 90s, expansion had outrun practicality. Consequently, says Elrae marketing and information technology VP Michele Mancuso-Krollman, Elrae was struggling to meet customer demands in a fast-paced, ultracompetitive environment.
"We were having difficulties with on-time deliveries and shipping deadlines. Basically we didn't feel that the system we had could handle what we needed to remain successful."
After an extensive search, Elrae opted for a Made2Manage Enterprise Business System for its unified front-office, back-office and production operations. "In the contract manufacturing / metal-forming industry, accurately tracking job costs is vital," Mancuso-Krollman says. "Our system lets us see every job we're running in real time. Because information is always real-time, we know exactly where we are regarding cost -- and we know where the problems are."
Punch Three Times
Once it had the wherewithal to handle many customer projects simultaneously, Elrae turned its focus toward effectively responding to its demanding customers. In doing so, it could let its technological capabilities - which had been the reason for its great success in the 90s - again assume prominence.
One Elrae customer wanted to accurately punch three holes on one side of a plastic channel extrusion for a leading office product manufacturer. The bad news: the flexibility of the part made it difficult to maintain hole locations while achieving repeatability. Moreover, the parts had to remain clean and burr-free after the holes were punched - so material handling also was an issue. If parts had slugs left in the holes after punching, the functionality of the end product would be compromised.
Elrae was told that a former supplier had attempted to punch holes with conventional brake press tooling. The consequence: excessive scrap, poor quality, and late shipments.
Elrae's solution was to punch the holes with a conventional stamping press. The company designed and built a low-cost tool that allowed the extrusion to be held in place on three axes (XYZ), enabling holes to be punched cleanly while slugs could be removed safely.
By using the stamping press, Elrae increased production significantly over the prior vendor's hole-punching process. The process met the customer's tolerance and repeatability requirements, reduced unit costs, eliminated scrap, and increased efficiency.
It may well be, however, that the customer was happier over another result -- turnaround time for the subcontracted stamping operation was cut by more than two-thirds.
Rising Tensions?
Another customer, a plastics injection molding job shop which was a top supplier to automotive and recreational customers, developed a tension bar for use in a car door. The automaker's initial design called for a die with close tolerances. Parts would be injection molded to form the final plastic assembly.
The die incorporated an extrusion-like shape made from a high strength/low alloy material. Hole tolerances and the thickness of the wall of the extruded neck were critical to ensure that the bearing fit properly in the final door assembly.
"The customer's need was quite clear to us," Mancuso-Krollman says. "They wanted an alternative to the high cost of procuring the die cast part. Given volume requirements, they also wanted something that enabled faster production."
Elrae assembled a group of its most seasoned staff members in what it called an "Early Supplier Involvement team." Their conclusion: the part could be extruded and sized using progressive die stamping technology.
After testing the idea with prototypes, Elrae presented it to the customer, who accepted. The consequence: progressive die technology increased production efficiencies, enhancing the customer's ability to meet rigorous JIT delivery schedules. Quality and repeatability improved across all components in comparison to multicavity die cast operations which, Mancuso-Krollman says, could cause component variation. Unit prices dropped and the customer ultimately used the same technology on four additional parts, enabling expansion into new markets.
Ratcheting Up Hand Tool Sales
A major retailer told a leading hand tool manufacturer it wanted an aggressive expansion of their product line. The manufacturer brought a development sample of one proposed product to Elrae for help in design, development, and manufacturing.
The major challenge was the retailer's brick-wall deadline. Again calling on its "Early Supplier Involvement team," Elrae researched whether and how it could produce the entire assembly. Ultimately, the team separated the challenge into distinct components: designing and building equipment, assembly lines, and dedicated product work cells.
Elrae's customer accepted the company's proposal but carried it further, asking the company to add packaging and point of purchase displays to its execution plans. The final tool was ready ahead of schedule and under budget, enabling the retailer to reduce its retail pricing which improved its competitiveness.
Cool Removal of That Oily Build-up
A "Big Three" automaker redesigning a cooling system wanted to produce a family of seven components as
a metal stamping. The differences among components were two part widths and seven part lengths.
"Providing the parts as metal stampings required individual part dies or a complex family of dies with interchangeable inserts," Mancuso-Krollman recounts. The parts also had to be oil-free.
"We told the customer that we were concerned about the numerous tools, different material widths, set-up time and cost, part quality, and consistency that were all associated with producing the product family as a stamping. Cleaning the parts after shipping was another issue, since it required an additional step and more handling. It all came down to cost and timing. The existing scenario would have made it difficult for any stamping house to produce the products at the target price while meeting shipment schedules."
The same Early Supplier Involvement team recommended the parts be roll formed, not stamped. "We designed and built a customer-dedicated roll forming work cell with an in-line automated wash system. The work cell could expand as requirements increased, which means that one operator can run two roll forming lines while using the existing in-line wash system."
What were the advantages of this solution? "Roll forming eliminated the need to procure seven different widths of material and the seven different set-ups required for them, if the parts had been produced as a stamping. Roll forming enables you to perform a small timing adjustment to vary part width.
"We also recommended oscillated aluminum coils instead of the traditional pancake type coil. Oscillated coils can hold more material, so we could increase output per hour," Mancuso-Krollman recounts.
The drop in material handling and set-up requirements brought the project in 10% below the customer's target price, while narrowing material requirements from seven to two sizes enabled Elrae to realize economies for oscillated material.
The roll forming process increased production capacity and improved JIT shipments while providing high quality, tighter tolerance parts consistently.
And Now, A Word From . . .
A leading advertising specialty company supplying a global adult beverage producer with Point of Purchase (POP) displays faced several challenges:
· Ensuring on-time delivery coincident with seasonal sports promotions
· Coping with a final assembly vendor who was running two months late and couldn't deal with supply logistics
· Solving excessive shipment costs stemming from poor part design
· Dealing with damaged goods caused by less than optimal assembly processes
"Our sales engineering team came up with design changes which improved product and package stability," Mancuso-Krollman says. "The customer approved the changes and we had production underway in 72 hours, with fixtures built and assembly work cells in full production."
Elrae's design changes improved product integrity and ensured that the complex assembly arrived at the final shipping point in one piece, virtually eliminating costly customer returns. The design also enabled shipping costs to be cut in half.
Moreover, on the basis of the first project's success, Elrae was awarded another POP display. Using similar design concepts on the second display cut its shipping costs by more than two-thirds.
Down Year?
Despite its clearly high degree of inventiveness and technological wherewithal, Elrae is a company of pragmatists. In 1999, it prepared for what it expected would be a down year - with some surprising results. Its conservatism improved its ability to focus its resources on customers. Some highlights of those preparations:
· Second Shift Staff Reductions: Since Elrae's second shift consisted mostly of temporary workers, it laid off one foreperson and one draftsman
· Executive Wage Controls: Wage increases for top executives were capped
· Efficiencies from Software: ERP efficiencies resulted from Y2K upgrades
· Accounting Staff Reductions: Department reduced by two
· Real-time job costing: Allowed in-process jobs to be monitored
· Utility Studies: Partnered with local utility services to reduce energy use
· Increased Marketing Expenditures: Unlike many other companies, Elrae increased marketing in the face of potentially declining business levels
· Doubled trade show attendance: (JSS)
· New Plant Layout to speed material flow and enhance efficiency
· Inventory accuracy team: increased accuracy to 98%, resulting in better MPS and MRP planning and scheduling and consequently, improved on-time shipping and sped product throughput
· Sales Force Reorientation: Instead of positioning Elrae as a stamper, they now probe to determine what additional services Elrae may perform. They ask "What is this used for?" and "Do you need a subassembly made?"
· Early Supplier Involvement program focuses first on customer needs, then on what needs to be done, and finally on determining how Elrae can make it happen
· Employee Cost Saving Suggestion Program gives employees cash awards and time off for submitting cost saving suggestions
· Reviewing ISO9002 and QS9000 methodologies, JIT, and Lean Manufacturing principals for continuous improvement opportunities.
In 2000 - 2001, Elrae had projected a 15-20% reduction in sales and a loss. Its "down year" preparations made the year profitable. Among other things:
· Elrae's first shift operation was able to produce 90% of combined first and second shift production
· Sales to Direct Labor Hour increased 28%
· Sales to Indirect Labor decreased 8%
· Annual Contribution Margin increased from plan and previous year budgets / actuals
· Record safety; there were no lost time accidents in 1999, 2000, or 2001
· Elrae's building addition made Elrae attractive to many companies strictly for assembly work. Currently many assembly jobs in house contain no metal forming parts.
* * *
All trademarks used in these articles are the property of their respective owners. Copyright, © Job Shop Technology magazine, 2002. Reprinted with permission by JMB Communications.
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