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Long Island Company Maintains Sharp Focus on Specialty Metal Alloys
Pictured are some of the numerous parts that Romac stamps and machines out of the alloy Kovar. Photo courtesy of Romac.
Precision machining and stamping firm sees beyond night vision into other durable alloy uses
Mark Langlois, Senior Editor
Romac, an ISO 9001 certified contract manufacturer in the stamping and the machining of hard-to-work metal alloys, is broadening its manufacturing focus beyond the military night vision applications that helped grow the company since its inception in the 1950s. The company, based in Plainview, New York, works with numerous hard-to-fashion specialty metal alloys, including Kovar®, titanium, stainless, Inconel, Hastelloy®, and other dense and corrosion-resistant metals many shops shy away from.
"When you see a cutting demonstration at a trade show, they're always using aluminum or brass. That's like putting a knife through butter. Any shop can do that," said Lee Bloomberg, whose grandfather, Mac Bloomberg, founded the company in the early 1950s. Mac passed it on to his son, Jerome, who moved the 10,000-square-foot shop to its current 42,000-square-foot location in 1978. Lee is the third generation. "We have what you might call a micro-niche in specialty metals."
In recent email and phone interviews, Bloomberg and Romac General Manager Al DeBello explained the difference between what Romac does with metal alloys and what other firms do with free machining metals. Kovar and other metals that Romac works with, they said, are very hard on the tools.
"These aren't the kind of materials you press a button and go 'lights out,'" Bloomberg said. Machinists don't walk away from a lathe or milling center when machining Kovar. "There's a certain amount of labor intensity to our work. We're constantly checking and making adjustments."
DeBello, who has been in his role as general manager with the company for 30-plus years, said that when cutting these customer-specified high temperature electronic alloys, the carbide tungsten inserts and carbide end mills have a much shorter life versus those machining brass or aluminum.
"On some components, we may only run 50 or 75 parts before the tool must be changed. We throw the old inserts out and replace them with new ones at a cost of upwards of $20 each, which adds up, as some annual production runs are north of 100,000 pieces," DeBello said. Machinists, operators, and roving quality assurance (QA) inspectors are constantly monitoring the work in process to make sure the parts meet critical dimensions, sometimes +/- 0.0005 inch. "These are fussy metals. We're constantly adjusting. They require hands-on attention. Each operator is trained to check critical dimensions on every part coming off the machines."
Metal Parts for Hermetically Sealed Devices
Romac is a prominent supplier of component metal parts used in assemblies that require a hermetic (airtight) seal, which is typically a seal between metal and either glass or ceramics. The expertise that Romac brings to the process is knowing which metal will expand or contract at the same rate as the glass or ceramic.
Hermetically sealed devices are frequently used in high-temperature and high-stress environments, such as medical X-ray tubes, image intensifier tubes, photo cathode tubes, oil and gas detection instruments, fiber optic feed-throughs, and electronic packaging. Kovar, a metal alloy consisting of nickel, cobalt, and iron, is typically used for hermetic seals as it has the same coefficient of expansion as glass or metalized ceramics. There are other nickel-based alloys, such as 42 alloy, 46 alloy, and 49 alloy, that are also used in these sealing applications.
Kovar itself is 29 percent nickel, 17 percent cobalt, and a balance of iron and other trace elements. It's difficult to fabricate because the nickel is soft and gummy, but cobalt is hard and abrasive, DeBello said. "It's the combination of the two that makes it difficult to work with. It's part art, part science. Years of experience to determine the right feed rates, spindle speeds, choosing the right cutting inserts and end mills, and adding intermediate annealing processes when needed, have made us experts in the last five decades."
Romac's components are used by the military, telecommunications, fiber optics, in oil and gas production, in aerospace applications, and by the medical industry. The military side of the application, the use of specialty metals in image intensifier tubes (IITs), is slowing down because the wars in Afghanistan and Iraq are winding down. Romac is changing its customer mix to rely more heavily on civilian applications than on military applications.
"It was almost standard issue that anyone with a uniform, and you're talking hundreds of thousands of troops, had a night vision device in the most recent Mid East conflicts in Iraq and Afghanistan," Bloomberg said. "We were helping fight the war on terror. However, when the military draws down, the troops don't keep the systems. That created a larger than expected inventory of night vision systems, reducing the DOD's demand."
Romac lost some of its non-military business to overseas providers who appeared to be manufacturing parts at a cost below where Romac thought it could compete, Bloomberg said.
"Ironically, some of that business is coming back to us. The lion's share of that business went to India. There are some very talented people in those countries who work for a lot less than we do. We were making a high-purity nickel part for $60 or $70. I think they were buying it in India for $15 or $20," Bloomberg said. For an OEM watching pennies, that deal was too good to pass up.
Offshoring didn't appear to last for some customers.
"Logistically, the way it turns out, it isn't the best thing to be working with some of these countries," his former customer decided, Bloomberg said. The work may return to Plainview, New York. "We've been working with the company for six or eight months that is bringing work back. They've already paid for the hard tooling. That's a good sign. It's a big investment on our part. Hopefully, it's worth it, as the first article samples are in the approval process, with production scheduled for 2017."
A Multi-function Fabrication Facility
On the factory floor, Romac combines stamping with CNC machining, in part to lower costs for its customers. To upgrade the company's milling, it is about to buy three Okuma 3-axis CNC turning centers with live milling. Romac employs about 40 people in its 42,000-square-foot plant that houses 50 presses and 50 milling and CNC machines. "In addition, we have a custom degrease, tumbling, vibrating, and finishing department, so parts are cosmetically clean when they are leaving our facility," Bloomberg said. The company's strategic partners perform other value-added tasks, including heat treating, grinding, plating, electro-polishing, EDM, and photo etching.
The alloys Romac uses are sometimes 10 times more expensive than copper or aluminum, so the company designs its own manufacturing processes to limit waste. At those prices, limiting waste is a core value. It frequently stamps a part first, before machining it, to reduce the amount of milling required. The closer the part is to "near net," the less waste from milling. When Mac Bloomberg founded the company in the early 1950s, it was a stamping company. Today, it has evolved into a multi-function fabricating facility.
"We have to look at things differently," Bloomberg said, because its customers want the hardest, most durable metals at the lowest cost. Wasted metal is wasted expense. That insures Romac walks the environmental walk.
By way of example, Bloomberg and DeBello described a cup-shaped part that they manufactured for a medical firm. It was about two inches in diameter and one inch deep. It had five holes bored in the bottom. Four of the holes had counter bores. Bloomberg said a typical machine shop would buy bar stock, cut it into slugs, and machine the part out of the slugs, thereby wasting nearly 80 percent of the metal in the machining. The raw material is Kovar, costing up to $30 per pound, so all that excess machining to create the cup space is just waste.
Instead of buying and cutting a bar, Romac buys the Kovar in a flat strip 0.160-inch thick, blanks a disc in one press operation, and deep draws a cup shape from the disc in another press operation. The company then machines the cup to the proper specifications. "We estimate a 40 to 50 percent saving for our client in material alone," Bloomberg said.
"We have stamping alongside CNC machining. We've always prided ourselves on having the combination. We look at things differently than a typical machine shop," DeBello said. "We do it in-house. You can imagine taking a whole solid piece of bar material and hogging out all that material that can cost $25 or $30 a pound, versus taking a thin strip and forming the material first."
In addition to improving the process by not wasting Kovar, Romac's experience in hermetic seals also taught the company that a Kovar bar and Kovar sheet are different. DeBello said that sheet or even thicker sheet material, called plate, has a fine-grain deep draw material. At the molecular level, sheet Kovar is different and better than a piece of bar material for a hermetic seal. "It has a much tighter and finer grain structure than a piece that was hogged out of a bar," he said.
Bar material tends to have inclusions or stringers within the bar, Debello said, explaining that inclusions and stringers are micro-sized holes that can cause vacuum leaks in a hermetic seal assembly.
These little inclusions can get stretched out though the bar. They're micro-sized holes that can't be seen or detected without a microscopic inspection. "If you have this micro-sized hole going through the part and you do a hermetic seal and try to pull a vacuum on that, you're going to have a leaker," DeBello said.
The cup-shaped part described by Bloomberg and DeBello is used in a subassembly for the anode section of a medical X-ray tube that is subject to tremendous heat, stress, and friction. The Kovar alloy is essential because the part will ultimately be brazed to ceramic or glass. They must expand and contract at the same rate or the glass or ceramic will break. In addition to night vision goggles and X-ray tubes, hermetic seals are used in deep space exploration, deep water exploration, and in other high-pressure, high-temperature environments.
Precision Stamped and Machined Parts
"We are able to engineer a manufacturing process in the hard-to-machine alloy that resulted in a better, less expensive part for our client," Bloomberg said. He said most OEMs want quality parts at a good price. When he talks about what Romac does, he doesn't think or talk about the tiny niche market. "I try not to focus [on whether] it's for an image intensifier or a night vision device. It's a precision stamped or machined part. We do a lot of deep-draw work, and that's unique in the industry."
One of Romac's advantages is that engineers work out a manufacturing process for each part that keeps the cost down and the tolerances accurate. "We are contract manufacturers, meaning we make components to customer specs. Once we get the prints, it's up to us to determine the most productive manufacturing method to deliver the final product," Bloomberg said. Digital prints are uploaded to CAD/CAM software, and the mechanical engineer will methodize the process. A production schedule is set, usually in economical batch sizes, along with an operation traveler sheet, which accompanies the part through every operation through final inspection, packing, and shipping.
Romac's quality record is a testament to its success as witnessed by the loyalty of its customer base. Bloomberg said, "Our three largest customers have been buying components from the Romac facility for five decades." The company's rigid focus on its quality management system, centered on continual improvement and meeting and exceeding quality goals, is a cornerstone of the company's quality assurance department. The company has lean manufacturing processes in place, including SPC at the machines where required, pushing Romac to 5 sigma (approximately 200 defects per million) on certain parts.
"We have a good mix of business now," Bloomberg said, meaning a good combination of milling and stamping projects. "Depending on the required manufacturing method, stamping, turning, milling or a combination of it all, our production engineers will custom design the appropriate tools, dies, or fixtures. It's really the combination that makes us competitive."
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