The Digimar 817 CLM height-measuring instrument initiates measurements three ways: via a normal keypad, QuickMode, and Speed Keys. It is designed for easy programming and to reduce the time it takes to inspect a sampling of pieces. The unit comes from Mahr Federal (Providence, RI, U.S.; www.mahr.com).
Coffeemakers have been around for many decades, and you might think that safety testing would be pretty much standard across brands and models. Not so. Just as there’s differentiation among brands and models, it follows that testing is becoming differentiated as well.
That’s just one of the drivers of change in the world of testing and test equipment. Other drivers include use of new materials, ever-evolving environmental standards, and appliance OEMs’ mission to squeeze every bit of value out of products and processes.
Drivers of Change
“Testing challenges are as varied as the things we call appliances,” says Alex Porter, engineering development manager for Intertek (Boxborough, MA, U.S.; www.intertek.com). “With white goods there’s a lot of price pressure, so we do testing to reduce the cost of quality. With medical appliances there’s a bigger margin and a need to go beyond FDA regulations to eliminate incidents and provide extreme reliability. With consumer electronics, there are two categories: the high-end products that demand performance and long life, and the products you buy at Wal-Mart for $20.”
Porter says one driver of change in testing is that differentiation is maturing between high-end and low-end appliances. Each operates on its own business model. “There’s the pure point-of-sale product where the price on the shelf is the only decision point for the consumer versus the more forward-looking purchase, where the consumer is looking for performance and durability and is willing to spend more money. They have different testing requirements. They all have to meet minimum safety regulations, but the information needed by the appliance industry for decision making requires different test plans.”
One example of differentiation is safety testing for a $10 coffeemaker versus one that costs $500. Basic safety testing addresses products at the beginning of life. But the consumer expects to use a $500 coffeemaker a long time, so it must be aged and tested for safety.
Adding another layer of complexity is the multicontinent sourcing of products. “Testing must be able to support a multicontinent validation program because components are being made in more than one location for more than one end-use application, but they’re run as a single project,” says Porter. “To be able to handle a multicontinent validation plan, we’re faced with the global perspective. It’s very different from putting up a lab a few miles from the facility. There might be five different locations.”
Testing New Materials
For reasons such as environmental compliance or savings on material and processing costs, appliance OEMs are pressured to find and develop alternative materials. This presents a challenge for providers of testing and testing equipment as well.
One example involves the substitution of plastic for metal parts. “Many industries have started switching to coated plastic parts in lieu of metal parts to reduce weight and cost,” says David Beamish, general manager of DeFelsko Corp. (Ogdensburg, NY, U.S.; www.defelsko.com). “They’re looking for a way to nondestructively measure coating thickness on nonmetals.”
DeFelsko recently released the PosiTector 200 to meet the need for nondestructive measurement of coating thickness on plastics and other nonmetal components like wood. Beamish says the palm-sized device uses a nondestructive ultrasonic technique that conforms to ASTM D6132. “It’s an affordable choice specifically designed to quickly and accurately check coatings that include paint, varnish, or lacquer on plastic, wood, and other nonmetals. It eliminates the need to repair coatings or scrap parts in order to accurately measure their coating thickness. Also, fast measurements allow for large surface areas to be tested quickly without disrupting your production process.”
DeFelsko’s PosiTector 6000 measures and records paint and coating thickness on all metals. The Memory version of the coating thickness gauge can boost manufacturing efficiency and reduce paint and material costs. Up to 10,000 readings can be stored in 1000 batches for analysis and downloading.
Testing as Process Control
“It is imperative that appliance OEMs measure the coatings on their products in order to control cost and quality,” says Beamish. More testing means better control of materials use on powder coating paint lines, for example.
“The testing and measurement of powder coating before, during, and after setup can result in a more efficient coating process,
saving money. DeFelsko provides coating-thickness gauges that are advanced yet easy to use, enabling a manufacturer to have the process control needed without having to spend money learning or teaching others how to understand the instrument.”
DeFelsko’s PosiTector 6000 measures and records paint and coating thickness on all metals. The Memory models have features to improve manufacturing efficiency and reduce material costs. For statistical process control, these models continually display and update the number of readings, average, standard deviation, and minimum and maximum thickness readings while measuring. High and low limits can be set to provide audible and visual alerts when any measurement exceeds specified limits. Up to 10,000 readings can be stored in 1000 batches for analysis and downloading.
Testing for Robustness
Porter of Intertek says that robustness is a big issue for certain product segments, especially medical appliances, high-end consumer electronics, and commercial refrigeration. “Robustness goes beyond reliability. You can design a product for reliability that will work well if used properly, but will fail if you don’t use it properly. That’s the opposite of robustness. Robustness is about how much abuse can I give it and it will still work right. For example, in medical appliances, you don’t know how ER responders are going to use equipment. It’s not enough for the product to be reliable under nominal conditions. It must be robust under a variety of unanticipated conditions and last a very long time.”
To test robustness, Intertek uses its proprietary Failure Mode Verification Testing (FMVT), invented by Porter, and other testing techniques to take the product under various stress conditions to the point of failure. FMVT typically addresses stress sources that include six-axis vibration, temperature, humidity, voltage variation, contamination, UV or solar light, and dynamic loading.
The Fischerscope X-ray XDAL from Fischer Technology provides nondestructive testing of hazardous substances in electrical and electronic equipment. Used to measure plating, paint, and powder, the instrument performs double duty by detecting wasted material due to overcoating along with testing for RoHS and WEEE compliance.
More for Less
“Do more for less” is almost a universally held doctrine among appliance manufacturers. Providers of testing and testing equipment are challenged not only to help their customers meet product goals for cost and quality, but also to ensure that the testing itself is reliable and cost-effective. This is certainly true for IneoQuest (Mansfield, MA, U.S.; www.ineoquest.com). The supplier’s customers are consumer electronics OEMs—specifically, companies that design and manufacture cable-TV and telephone-company video set-top boxes for digital video. Jim Welch, IneoQuest’s lead test and measurement engineer, says a high priority for customers is to have low-cost testing gear that aids the design process and postbuild without having to buy, build, and maintain a lab full of cable TV head-end equipment to emulate their customers’ environment.
Manufacturers of equipment for digital TV communications applications face an extremely unforgiving operating environment. Any transmission loss, even a single packet loss, can cause a visible or audible impairment, and subscribers tend to be intolerant of the resulting freeze frames or audio clicks on their TV sets. Set-top boxes must provide a steady and clear picture in spite of occasional transmission problems. The technology that makes set-top boxes somewhat tolerant is known as “error concealment,” and the boxes can use fairly sophisticated algorithms to accomplish it.
One challenge of product development is to emulate cable TV and Telco video distribution networks consisting of hundreds of channels and different types of communications protocols, both with and without controlled, repeatable transmission impairments such as packet drops, jitter, and malformed video streams.
“The ability for the set-top box manufacturer to use the same cost-effective test and measurement equipment that their customers are using in live systems is unique,” says Welch. “Historically, lab test gear has been much more complex and expensive than that used for live operational monitoring. IneoQuest uses the same cost-effective platform for both applications with only a reload of software and firmware to repurpose and customize the platform. This facilitates communicating anomalous behavior and events between the two users and results in faster and more-efficient problem solving when needed. This saves operating expenses for the service provider and maintenance and revision costs for the set-top box provider, and results in less faulty operation, which every TV viewer wants.”
Besides working with network equipment providers in their labs, IneoQuest personnel often work with service providers in debugging problems on-site at customer premise locations and at head-end and hub sites, which are the control centers that process signals from satellites, local TV stations, and other sources so they can be transmitted to customers’ homes. “This has given us the firsthand understanding needed to develop the best test and monitoring capabilities across the industry,” says Welch.
Speeding Time to Market
Testing strategies and tools often serve appliance OEMs and suppliers in speeding the time to market. Approaches include maximizing testing efficiency and improving process controls.
One of the most important ways Intertek helps customers is through synthesizing validation. Porter introduced the concept in his book Accelerated Validation and Testing in 2004. It’s a strategy that prioritizes tests to maximize testing efficiency so that manufacturers can save from 50–60% on validation time and material. “It’s not new, but we’re using it more and more, and about half the applications are with the appliance industry, especially for medical equipment,” he says.
Fischer Technology’s Dualscope FMP100 is a timesaving tool designed to cut the time it takes to adapt documentation to suit the different formats OEMs require.
“For example, terminology such as job number, lot number, or other user text might be different for each company,” says Paul Lomax, marketing director for Fischer Technology (Windsor, CT, U.S.; www.fischer-technology.com). “Likewise, a customer might require statistical data such as standard deviation to be the second item on the left-hand side of the report, another might require it to be the third item on the right-hand side, and another [might want it] elsewhere.”
The Dualscope is a portable instrument for measuring coating thickness. Unlike traditional instruments, it is Windows-based so there’s little user training required, and has a color display touch screen and drag-and-drop features. “It’s a revolutionary concept,” says Lomax. “In the past, people would take a reading, dump it into the computer, and manipulate the data on a spreadsheet for the format they’re asked to provide. This instrument allows the user to drag and drop data with a stylus to create reports for whatever parameters the OEM requires. You save the report as a PDF file and attach it to the shipment of parts. If you’re required to provide documentation, the time it previously took to input data into a report format has been greatly reduced.”
Lomax adds that Fischer’s testing is distinctive in the precision of its equipment and its extensive selection of application-specific probes and measurement devices. For example, one probe is designed to measure thickness on a rough surface. “When it comes to controlling material cost, if you don’t use an application-specific probe, you might get a reading but not achieve the best results. Probe selection therefore is an important part of the instrument selection criteria,” says Lomax.
Electromatic Equipment Company, Inc., (Cedarhurst, NY, U.S.; www.checkline.com) offers the PK2X Pocket Stroboscope to freeze or slow down action for performing noncontact measurement of rotating or reciprocating parts. Improvements in the redesigned tester include a 50% brighter flash, 100% longer battery run time, and the choice of ac power mode for continuous operation or use while recharging the battery.
Testing That Does Double Duty
Testing for one purpose sometimes ends up serving another purpose as well. A good example is when hidden material costs are revealed during stress tests or hazardous-materials tests.
In some cases, testing for robustness can reveal potential savings in material costs by identifying materials that are stronger than necessary. “We were able to demonstrate to a dryer manufacturer that they could reduce the gauge thickness of sheet metal without impacting their warranty rate,” says Porter. “Similarly, we examined process changes for optimizing bracketry in an appliance motor and found it could be designed to use less metal and end up being stronger. We reduced cost and improved robustness at the same time.”
One challenge for manufacturers and suppliers is the need to comply with environmental regulations such as the European Waste from Electrical and Electronic Equipment (WEEE) and Restriction of Hazardous Substances (RoHS) Directives. Testing is an essential part of compliance, but it takes time and preferably involves a nondestructive method.
“OEMs need a screening program they can accomplish in a timely manner and still meet delivery requirements,” says Lomax. “One of the advantages of x-ray fluorescence is that no elaborate sample preparation is necessary. Depending on the sample, measuring times for specified detection limits are relatively short, thus an increase in throughput [results].”
X-ray fluorescence provides OEMs fast, nondestructive screening for RoHS. A measurement provides direct results of the concentrations of mercury, lead, and cadmium. Suppliers explain that if the total content for chromium or bromine is measured and the respective limit value is not violated, it is safe to say that hexavalent chromium (Cr VI) or polybrominated biphenyls (PBB) and polybrominated diphenyl ethers (PBE) are under the limit value as well. Additional analysis methods to determine the Cr VI, PBB, or PBE content are required only if the limit value is violated.
Employing x-ray fluorescence to test for environmental compliance can also have the advantage of helping a manufacturer or supplier reduce material costs when it comes to measuring plating thickness. “Whether we’re talking about plating thickness or liquid and powder coatings, no one benefits from overcoating or overspraying,” says Lomax. “If a liquid or powder coating needs to be 5 mils, but they find by using our equipment they’re consistently applying 5.5 mils, that represents unneeded material costs. By researching the best coating thickness instrument, whether a handheld or benchtop instrument, and the probes best suited for that application, they can reduce the amount of powder or liquid on X number of parts, and over the course of a year they can achieve a measurable cost reduction. The investment in a $1000 piece of handheld testing equipment could save them 10 or 20 times that amount in reduced material costs. The same holds true with x-ray fluorescence instruments, especially now that the price of precious metals used in plating applications has dramatically increased.”
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