Shop Solutions: Cells Keep Manifold Production Flowing
Manufacturing cells that group machine tools together for processing components made from similar materials and families of parts are key to a lean environment. Cells allow manufacturers to better manage their workflow, parts quality and ultimately operate faster and more productively. Daman Products Co. Inc. (Mishawaka, IN), a leading hydraulic valve manifold shop, has long relied on manufacturing cells to achieve higher productivity levels, improve on-time delivery as well as increase its responsiveness to fluctuating market conditions.
When Larry Davis’ father, Jack Davis, founded Daman in 1976, he didn’t have any manufacturing experience or any orders in hand. Jack did, however, push the company forward through perseverance and fiercely defending the belief that quality sells, and that impressing the customer at every opportunity is vital to success—a mantra that Larry and the Daman team obviously continue today. Daman has purchased the most reliable, high-performance equipment, like its two new Mazak HCN 6800-IIs to stay on the cutting edge of manifold design. The company has also implemented realistic programs and strategies that put the interests of its customers first.
Daman specializes in both standard and custom-engineered manifolds. Over the years, the company started incorporating manufacturing cells as a way of becoming an efficient, single-source supplier of manifolds. The company runs three shifts up to six days a week and divides its workflow between four different machining cells, based on material type, product size and standard versus custom work. A typical cell configuration at Daman consists of two or three standalone machine tools. Two cells are responsible for machining aluminum parts, another for ductile iron, and one for machining both types of materials.
The company relies on HMCs and VMCs from Mazak Corp. (Florence, KY) to give each cell the appropriate level of versatility and capacity required to meet the varying needs of more than 2000 customers. Daman purchased its first Mazak machine in 1985 and currently has a total of 13. The manufacturing flexibility provided by machining cells allows Daman to produce lot sizes ranging from one piece to thousands and various components from simple circuit blocks to complex integrated circuits. Typical manifolds require part tolerances that are within ±0.015" (0.38 mm). Based on customer needs, however, Daman must often hold tolerances within ±0.005" (0.13 mm) as far as part feature locations are concerned. As a whole, Daman products meet or exceed the standards set forth by the National Fluid Power Association (NFPA), as well as specifications by the International Standards Organization (ISO).
The company celebrated a record-breaking year in 2011 with a 30% increase in orders due to the economy picking up steam, and the hydraulic and pneumatic industry experiencing an overall increase in business. In fact, by the end of 2011, fluid power shipments were up over 22% when compared with 2010. To keep up with its surge of incoming orders and accommodate its projected double-digit growth for 2012, Daman had to increase the production capacity of two of its existing cells. It acquired two new Mazak Horizontal Center Nexus (HCN) 6800-II machining centers, one of which features a special 240-tool hive system. Both machines were acquired from the shop’s Mazak distributor, Machinery Systems Inc. (Schaumburg, IL).
Daman is also in the process of adding a 24,000 ft² (2230-m²) addition to its current 47,000 ft² (4366-m²) manufacturing facility. According to Larry Davis, Daman president, the company’s decision to do so and increase capacity through new machine tools evolved naturally. "Increased sales demands, particularly with our custom orders, and consistent extensions in lead times led everyone in the company to the same conclusion: it’s time," says Davis. "And with the expansion, we anticipate adding two more manufacturing cells within the next one to five years."
The new HCN 6800-II with the Mazak Tool Hive is located, along with two other machines, in Daman’s Cell B. When that HCN 6800-II first hit the shop floor last spring, it was operating alongside the only expandable 240-tool hive with the most sophisticated software available in the industry. "Once we put the Mazaks to work, we immediately started benefiting from their reliability, repeatability, and durability," says Davis. "Add to that the machines’ speed, and our cycle times also dropped significantly."
According to Tim McIntyre, Daman production team leader for Cell B, the HCN 6800-II has significantly increased the cell’s production capacity through its 24.8 × 24.8" (630 × 630-mm) pallet size with a load capacity of 3300 lb (1497 kg) and high-speed technologies. The machine’s features include a 10,000-rpm, 50-hp (37-kW) CAT-50 taper spindle and a rapid machine traverse capability of 2362 ipm (60 m/min). Linear guides on all axes of the HCN 6800-II enable Daman to maintain high levels of accuracy at fast feed rates, as well as reduce non-cutting time. The two-pallet changer allows employees to load, unload and inspect parts on one pallet, while the machine continues to work on parts fixtured on the other pallet. While most people in the industry use G-code programming, McIntyre prefers the Mazatrol Matrix Nexus conversational programming that’s available on the HCN 6800-II and credits the large tool storage capacity of the tool hive with bringing forth some of Cell B’s greatest efficiencies. "We can load and unload tools while we’re working on other jobs. That’s reduced our setup time to virtually zero."
Unlike chain-driven tool magazines, the hive and HCN 6800-II operate separately, with a robotic arm moving the tools to and from the pocket-changing area. Employees enter data into the tool-hive system in advance of production. Interactive programming allows the system to communicate job-specific tool requirements directly to the machining center. The hive holds approximately 200 of Daman’s most commonly used tools, including a variety of solid carbide, high-speed steel, and carbide-brazed cutting tools, which permanently reside in the hive.
Daman synchronizes its workflow using a WinWork philosophy, which streamlines internal processes and creates an empowering work environment. The company doesn’t believe in multiple layers of management, rather it goes to great lengths to hire the right people and give authority to people who know what to do with it. In fact, Davis says he and Vice President Dave Mischler are very hands off when it comes to what happens on the shop floor.
"The employees on the manufacturing floor know their jobs better than upper management ever could," says Mischler. "We don’t want them to have to waste time going through several different managers to get permission on something. We let employees control their own work, including buying their own tooling and material."
Mischler says on-going communication with employees is another key component of Daman’s WinWork philosophy. "We can’t stress communication enough," he says. "Everyone has full access to our work schedules, knows why company-wide decisions are made and can see the big picture of our business."
"What we’ve done is transform traditional jobs into dynamic, vital parts of an efficient organization," concludes Mischler. "Everyone at Daman is on the same page, which enables us to not only give our customers the products they want, but also the high levels of responsiveness they deserve." ME
For more information from Mazak Corp., go to www.mazakcorp.com, or telephone 859-342-1700.
Waterjet Expands Shop’s Business
Afocus on quality, full service and ensuring customer satisfaction have all helped Exact Tool & Die (Cleveland, OH), a stamping, tool and die manufacturer, to steadily grow its business. Adding a waterjet expanded it even more. After emigrating from Europe in 1952, Exact Tool founder Frank Chesek Sr. worked for a major US automotive company as a crane operator. He was intrigued by how tool and die makers produced car parts to exacting specifications. So intrigued that, at a substantial cut in salary, he joined a tool and die company’s apprenticeship program and later worked as a journeyman die maker for ten years.
With that experience, in 1978 Chesek started Exact Tool & Die, leasing a 4000 ft² (371-m²) building. Word spread about the quality of the products produced by his company and the attention to detail given to customer requirements. In 1993, the company purchased a plot of land and built a new, larger facility, expanded their capabilities from making metal stamping dies to include metal stamping. The company grew again in 2000, and their 68,000 ft² (6317-m²) operation now houses VMCs, EDMs, stamping equipment, and a CMM in the quality department.
The company, now led by Frank Chesek Jr., president, has customers that include the automotive industry, computer manufacturers, lawn and garden equipment builders, and the medical industry. Parts include stamping dies, motor brackets, oil-pan liners, air-bag components, deck brackets, and medical parts. The company’s employees average between 12 and 25 years of experience in providing complete turnkey work from designing and prototyping to die manufacturing, production runs, and inspection.
For over ten years, Exact Tool & Die outsourced to waterjet job shops its requirement for some die components such as stripper plates, parallels, and sub plates, as well as one-off prototyping parts. The alternative for a large portion of this work would have been saw cutting, but that adds a lot of labor—particularly in finishing. "We were very pleased with the parts produced on a waterjet, because there was little or no secondary processing," Chesek says. The $25,000–$35,000 the company spent each year on outsourcing was a cost they could pass on to their customers, but it also meant a lack of control over quality. Any delays in shipments from the job shop also were passed on to the customer, and that wasn’t the kind of customer service that Exact Tool & Die wanted to provide.
The tipping point came when Exact Tool & Die was asked to bid on a new project to build blank dies. It was a low-volume project for the shop, 10,000 pieces of 36 different parts. Stamping wasn’t the answer; it would take too long to make the dies and the cost would be too high. Chesek considered a laser, but part thickness and material would both be limited by the technology. It was time to consider bringing a waterjet in-house.
Exact Tool & Die selected a Flow Mach 3 system with Dynamic Waterjet and a HyperJet pump rated at 94,000 psi (6481 bar). "We considered several waterjet suppliers but were impressed with the higher pressure pump and the articulating cutting head offered by Flow International," says Chesek. "That was a big plus for us because it keeps the parts accurate and square. For thicker cutting or for stacked material, it’s a must."
Two types of cut-part quality issues plague abrasive waterjet parts: stream lag and taper. Both errors can be minimized by significantly reducing cut speed, but cycle time and cost per part rise with equal significance. Flow’s Dynamic Waterjet features Active Tolerance Control, which counters taper and stream lag to ensure that the waterjet is cutting at top speed, creating precision finished parts.
In addition, Flow's Advanced SmartStream mathematical models work behind the scenes to tilt the head to the side to eliminate taper and tilt it forward to control the stream. Combining the software with precision machine tool design and articulated wrist, taper-free parts are produced two to four times faster than on a conventional waterjet and to part tolerances of ±0.001" (±0.0254 mm).
From the operator’s perspective, eliminating taper is simple. All the mathematical calculations take place behind the scenes, triggering the appropriate motion commands to all five axes. The operator simply enters basic cutting parameters, including the type and thickness of the material being cut as well as the desired edge quality, and FlowMaster, Flow’s intelligent software, does the rest.
"Because our waterjet is optimized for fast accurate cutting, we have far better control over the speed we can produce parts for our customers as well as their quality," says Chesek. "We produce more off the waterjet than we thought we could. It runs eight to ten hours a day."
Besides winning the bid to produce short runs of a variety of blank dies, Exact Tool & Die has found their business has increased into new areas they had never considered before. "Word travels fast once you have a waterjet," explains Chesek. "For example, we are now cutting titanium and brackets for aerospace companies." Another customer needed to test weld seams in a metal tube so the waterjet was used to cut cross sections along the length of the tube.
A builder for commercial office space had a unique problem. His latest project used raised floors above the poured concrete floor to run wiring and ventilation. Removable plates made of concrete sandwiched between two plates of steel provided access. The customer was using a drill to cut a 6" (152-mm) diameter hole in the plates; each hole took one hour and one damaged drill bit to complete. He had to find a faster and more cost-effective way to complete the project, so he brought a plate to Exact Tool & Die to see what they could do. It took them 4 min to cut out the hole with their waterjet. The next day, the customer brought in the remaining 36 plates for them to finish. "It’s amazing what we’re finding to cut on the FlowJet," concludes Chesek. "We’ve not only added new customers but have also significantly expanded what we can do for our current customers. It’s proven to be a great complement to our other machine tools." ME
For more information from Flow International, go to
www.flowcorp.com, or telephone 253-850-3500.
Mist Collectors Clean Shop Air
Every shop owner or manager knows the importance of a clean shop environment, and mist collectors are a key part to maintaining this. Removing oil mist from the air improves shop air quality and reduces accident risk, fire risk, and overall shop cleaning costs. As Ziese Products (Park Hill, OK) discovered, the right mist collector can also make a substantial impact on coolant costs, part quality, and the bottom line.
A precision CNC shop serving the energy industry, Ziese Products prides itself in staying ahead of the technology curve. Owner Sean Ziese has run the shop with his father since 1992, and has maintained their competitive edge by implementing new equipment and processes to improve productivity and profitability.
Ziese contacted Vega Tool Corp. (Schaumburg, IL), the exclusive North American distributor for Amano Mist Collectors, regarding the issues he was having with his filtration-style mist collectors from another manufacturer. "We run production jobs, and having to stop the machines to change-out filters was cutting into our bottom line," says Ziese. "Additionally, our previous mist collectors were still leaving a thick oil mist in the air, and I didn’t want my team to have to work in that kind of environment."
For Ziese Products’ applications, Vega Tool recommended the Amano MJ Series filterless mist collector. "We offer Amano’s complete range of filtration style and filterless mist collectors," states Scott Fernandez, president of Vega Tool Corp., "but Amano’s MJ Series is truly the next generation of mist collectors. Since there are no filters to be replaced, it was ideally suited for Ziese Products’ needs."
The Amano MJ Series mist collector features a compact design that can be mounted on top of a machine tool or on a stand next to the machine. The internal cyclone spins at high speed, and the powerful fan sucks the air and mist from the machine. The coolant is returned to the coolant tank via a drain port, and the warm air is exhausted through the top of the unit.
In March 2011, Ziese installed its first Amano mist collector to reduce machine downtime and improve the air quality in its shop. Ziese noted an immediate improvement as soon as the machine’s doors were opened to change-out parts. "There was substantially less oil mist in the air, and the air temperature inside the machine was also lower than our machines outfitted with other mist collectors," states Ziese.
The Amano MJ Series that Ziese Products installed features a 99.9% collection efficiency of 2.0-µm particles. In addition to improving the air quality in the shop, the MJ Series mist collectors have provided an 8% savings in their total coolant costs over Ziese Products’ previous mist collectors.
Ziese now has the Amano MJ Series mist collectors installed on sixteen of their machines and the cost savings have started to add up. The prior mist collector manufacturer recommended replacing their $125 filters twice a year, and Ziese wasn’t typically able to get six months of life out of the filters. "Even replacing them at the manufacturer recommended intervals, across my 16 machines I was spending $4000 a year in filters," Ziese says.
One additional benefit of the MJ Series that Ziese wasn’t expecting was the removal of heat from the work envelope. The powerful cyclone has a collection capacity of up to 300 ft³/min (8495 L/min), which removes the hot air from the machine and exhausts it out of the top of the mist collector. "The Amano mist collectors keep a lower operating temperature in our machines, which has helped us to keep tighter tolerances and make better parts more consistently," states Ziese.
Ziese Products runs its machines for multiple shifts per day, and the Amano mist collectors are built for this sort continuous production environment. The case features a unibody outer shell, which eliminates any chance of coolant leakage from the mist collector’s housing. All MJ Series mist collectors use NEMA-compliant motors that provide both high efficiency and high power.
Eliminating the need for filter replacement has reduced machine downtime and provided a cleaner shop environment at Ziese Products. Although the MJ Series filterless mist collector is a small component in the machining process, the filter costs savings, reduced coolant costs, and work envelope heat removal have made a big difference in Ziese Products’ operations. ME
For more information from Vega Tool, go to www.vega-tool.com, or telephone 800-228-2969.
This article was first published in the June 2012 edition of Manufacturing Engineering magazine. Click here for PDF.