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Articles from 2001 In April


Suppliers Introduce Smaller, Lighter Valves

Originally Published MPMN April 2001

PRODUCT UPDATE

Suppliers Introduce Smaller, Lighter Valves

System solutions popular among device OEMs

Because valves are an integral part of many medical devices, new technology is constantly being developed to provide OEMs with better solutions for their fluid and gas control needs. Valves used in production environments are also undergoing transformations. Concerns of manufacturers include shrinking the size of their finished products by integrating smaller valves, maintaining sterility, and preventing clogging during production. A wide range of valve types with a large selection of properties and capabilities is available to accommodate any manufacturing requirement. Following are examples of some recent developments in valve technology.

Valve manifold features a range of configurations

The small size and flexibility of Pneutronics' X-System allow device OEMs to reduce the size of their products without sacrificing functionality.

As the medical device industry moves toward smaller and smaller finished products, suppliers are searching for new ways to reduce component size. Traditionally, valve manifolds are machined out of metal or plastic that may be heavier than desired, and can require special designs that are costly and time-consuming. In response to the demand for smaller, lighter valves, Pneutronics Div. of Parker Hannifin has incorporated its X-Valve into the X-System, a configurable manifold.

The X-Valve is an 8-mm-wide, two-position, three-way digital valve. The body incorporates all functional features in one glass-reinforced polybutylene terephthalate molded body. By combining the body and coil unit, the X-Valve can handle high flow rates at pressures from 0 to 30 psig. Vertically oriented electrical pins and female receptacles facilitate the use of common connectors. In addition, the X-Valve features a <10-millisecond response time and weighs 4.5 g.

Through the use of plastic components, the X-System provides a lightweight, durable assembly that can snap together with short lead times. It features a wide range of design configurations that can be tailored to suit various applications. "The X-System allows OEMs to radically shrink package size without losing the capabilities of much larger manifolds," says sales and marketing manager Bill Nissim. With an elastomer base for screwless assembly and fewer functional parts than most designs, the X-System minimizes tolerance issues and the potential for leaks.

Integrated fluidic platform consolidates fluidic components

Kloehn's system integrates solenoid valves and other fluid-control components to form one compact device.

Although a reduction in valve size is helpful to many medical device designers, they face another problem when combining valves with manifolds and pumps. Devices that use several fluidic components may require multiple suppliers and are sometimes bulkier and more costly than desired. In order to balance manufacturing needs with available technology, Kloehn Company, Ltd. has developed an integrated fluidic platform (IFP) that combines solenoid valves, manifolds, pumps, drive mechanisms, and fluidic lines. "The desire of OEMs to pursue smaller, more reliable fluidic systems for use in their equipment has allowed us to focus our efforts on integrating our broad line of fluidic components into a complete system," says vice president of business development John Delameter. "The IFP package can incorporate multiple devices and fluidic circuits, allowing for reduced package size and lower costs." An integral part of the IFP, the solenoid valve features low power consumption; chemically inert, the valve is available in two-way, three-way, manifold, and other multiport configurations.

Positive-displacement valve offers smaller shot sizes

As devices get smaller, manufacturers can increase their joining capabilities by decreasing shot sizes. Dispensit recently developed the Model 1230 positive-displacement dispense valve that features a 0.01-0.5-cm3 shot size, making it suitable for UV-curables and other adhesives and fluids. A variation on the pinch valve, the positive-displacement valve expands on the pinch-tube design with the incorporation of a metering rod. The valve is pneumatically actuated and can be combined with a servo or stepping motor to provide continuous flow or variable amounts of material.

The Model 1230 is divided into two parts: a wetted module that contains the metering chamber, and a power head module that pneumatically drives the metering rod. It is made of corrosion-resistant plastic and stainless steel. "The modular design of the Model 1230 dispense valve allows for easy maintenance and material changeout," says sales and marketing manager Mike Bloomhuff. It is suited for medical OEMs because of its high degree of accuracy and repeatability, he adds.

Pinch valves enable smooth, sterile operations

Some medical and surgical procedures require that fixed equipment be used for several patients. To ensure the sterility of transfer liquids or gases, manufacturers can use pinch valves with replaceable sterile tubing sets. Available from Bio-Chem Valve Inc., pinch valves that manage the liquid or gas flow within an instrument are designed to allow the sterile silicone tubing to slide out for easy removal and quick replacement. By eliminating the need for disassembly or removal of the valve from the equipment, patient contact is restricted to the sterile tubing.

The USP Class VI silicone tubing reduces the potential for clogging and sticking of aggressive fluids or blood within the instrument. "Pinch valves offer a combination of high reliability and low cost for equipment dealing with liquids that contain contaminants or particulates that could damage or clog other valves," according to company president Adam Meyers. Bio-Chem's pinch valves feature precision fluid control, an on/off function, and fluid-stream switching. They are available in normally closed, normally open, or three-way configurations. Inner-diameter tubing sizes range from 0.1 to 0.875 in. The valves are suited for devices used to isolate and divert the flow of high-purity fluids, blood, or saline in applications such as irrigation and aspiration, dialysis, and ophthalmology.

New ball-valve design reduces leakage

Because they can handle extreme pressures and a wide range of liquids and gases, ball valves are often used in sterile manufacturing environments. Although they are easy to use and have good high-temperature and high-pressure characteristics, ball valves rely on upstream system pressure for shutoff, resulting in the potential leakage of contaminants. Swagelok Co. has developed a compensating seat design for its 60-Series ball valves that maintains constant load on the seat against the ball on the upstream and downstream sides. A coned disk spring and support ring ensure a leaktight seal between the seat and the ball, even in the absence of back pressure. "Every bioprocessing system engineer is concerned about properly cleaning a system, but also about keeping it contamination-free following sterilization," says Neil Gavin, company biopharmaceutical market specialist. "As steam cools within the system, a vacuum can be created that tends to pull contaminants through the leaky stem seals that are inherent in most ball valves. When this occurs, the sterile condition is compromised."

The 60-Series ball valves have a two-piece chevron live-loaded packing that helps to prevent inboard and outboard leakage by compensating for changes in pressure or temperature. The valves are available in sizes from ¼ to 2 in., with a variety of handle, vent port, and remote actuation options. Available end connections include tube fittings in metric and fractional sizes, ISO tapered pipe-fitting ends, tube and pipe socket weld ends, and butt weld ends.

Needleless luer valves replace access ports

In order to comply with stricter safety requirements for medical devices, a line of valves has been developed to replace needle ports in IV applications. Offered by DirectMed, they are designed to fill, hold, and release a controlled amount of fluids on demand. Instead of using a needle to access fluid-delivery systems, the valves are activated by pressing and locking a regular syringe to the access port. "By providing needleless access to fluid-administration sets, medical device manufacturers can comply with the latest legislation for the prevention of needlestick injuries to healthcare providers," according to vice president of sales Louis Pagliara.

Benefits of the valves include high flow rates, 0.1-ml priming volume, and 60-psi back pressure. A hermetic seal between the syringe luer tip and the valve reduces leaks and ensures a minimal backflow upon syringe removal. The valves are made of gamma-stable, USP Class VI materials that are free of latex and diethylhexylphthalate. The valve stem and body mate securely with standard luer syringes and connectors.

Katherine Sweeny

Copyright ©2001 Medical Product Manufacturing News

Laser Drills Critical Holes in Blood-Gas Sensor

Originally Published MPMN April 2001

PROFILE

Laser Drills Critical Holes in Blood-Gas Sensor

Micromachining technology enables effective processing of acrylic optical fibers.

A multiparameter blood-gas monitor system combines fiber optics with specific chemical probes to directly measure blood chemistry and blood gases. The key component in the instrument is a small invasive probe fitted with three optical-fiber sensors that simultaneously measure CO2, O2, and pH and a conventional thermocouple for temperature measurement. The sensors are fabricated from acrylic optical fiber measuring 175 µm in diameter.

A primary challenge faced by Diametrics Ltd. (High Wycombe, Bucks, UK), which developed the system, was to find a way to repeatably drill consistently sized holes in the fiber. The firm settled on an excimer laser that was able to perform the exacting task without straining the production budget. The blood-gas monitor is marketed by Agilent Technologies and Johnson & Johnson.

"The probe had to be as small as possible to minimize insertion trauma, and maintain existing monitoring modes," according to Diametrics operations engineering manager Malcolm Jones. "It also had to be fabricated from biocompatible polymers that could withstand at least one cycle of sterilization." The plastics had to have suitable physical properties to support the micromachining of small holes and encapsulation of appropriate chemistries, he adds, and lastly, manufacturing costs had to remain low to meet market conditions for the disposable device.

Preventing Thermal Damage

During operation, light from an LED source is launched into the probe from a control unit and then reflected by a small stainless-steel mirror encapsulated in the end of each optical fiber. The light passes through a series of transverse holes drilled into the fibers in a helical formation. Light passing along the fibers interacts with the chemistry in the holes before returning to the control unit, where the return light intensity is measured.

The laser micromachining workstation developed by Exitech features an excimer laser with a 193-nm-wavelength beam. The image on the left shows the five-hole sequence created by the excimer laser.

Micromachining the small holes represents a critical step in the manufacturing process because the hole dimensions must be consistent to provide repeatability. Diametrics originally subcontracted the task to Exitech Inc. (Menlo Park, CA), a company that offers turnkey laser workstations and a range of laser processing services.

After testing, Exitech determined that an argon fluoride excimer laser was the best choice for machining acrylic fibers. Due to increased sales, Diametrics recently brought the job in-house, using a laser micromachining workstation supplied by Exitech. The laser outputs at a wavelength of 193 nm, in the deep UV range. "This is a perfect task for micromachining with an ultraviolet laser," says Exitech president Dafydd Thomas. "Ultraviolet light can be focused to much smaller beam dimensions than visible or infrared light," he says. "Ultraviolet light ablates polymers by directly vaporizing the material in a cold process, and it does not cause thermal damage to surrounding material," adds Thomas.

100µm

To form the holes, a spool of optical fiber is loaded into the workstation that automatically feeds a 1-m-long piece of fiber to the laser drilling head. Mechanical tension and a vacuum chuck rigidly hold the fiber. The laser beam is split using a set of mirrors so that all five holes can be drilled simultaneously without moving or rotating the fiber. This streamlines the process and ensures the holes' identical dimensions: each one has a rectangular shape with a 100 x 50-µm cross section that tapers to about 50% at the opposite side of the fiber. After drilling, a new section of fiber is automatically cut by means of a metal blade and stacked for further processing.

Machining Multiple Parts

Excimer lasers have been in use in industrial settings since the 1980s. They emit photons in the UV region without frequency conversion. Because of the incoherent and highly divergent nature of the beam, excimer lasers are suitable for multiple, simultaneous feature machining; splitting the main beam enables multiple part processing.

While excimer lasers can be configured to produce 308-, 248-, or 193-nm wavelengths, the most popular models are in the 248-nm range and use a combination of krypton and fluorine. They are highly reliable and can be used to machine most plastics. The 193-nm laser used by Diametrics is more expensive to operate, but its manufacturer claims it is the only laser of its kind that can directly break the strong chemical bonds of biocompatible materials such as Teflon and acrylic fibers. "In this case, laser micromachining is truly an enabling technology," notes Jones. "This task simply could not be performed by any other means."

Katherine Sweeny


X-ray Manufacturer Gets the Lead Out

Replacing lead with a thermoplastic-metal composite cuts costs, improves workplace safety.

Nobody likes lead and everybody would rather do without it. Xitec (East Windsor, CT), a manufacturer of x-ray fluoroscopy systems, had been using the heavy metal in its x-ray tube shield, a cylindrical part that helps to concentrate x-rays and to shield personnel from stray radiation. But safety issues and the costs involved with the use of this hazardous metal led them to search for an alternative material.

The costs and the effort involved in manufacturing the lead tube shield were continually increasing. Not only were materials suppliers passing along the rising cost of more-stringent regulatory controls, but Xitec had to beef up its safety controls and training for assembly and soldering procedures. Furthermore, the shield and especially a precision aperture at one end were prone to damage when the soft, malleable lead was handled prior to final assembly. Scrap was also a constant headache.

By using a thermoplastic metal composite instead of conventional lead, Xitec was able to reduce by 50% the overall production costs of x-ray tube shields.

In his search for an alternative material, Xitec chairman Dave Malcom heard about the EcoMass thermoplastic metal composite from PolyOne (Cleveland). The material is part of a new family of high-density composites that can be used as nonhazardous alternatives to lead and other high-gravity metallic materials in many applications.

Randy LaValley, Xitec's mechanical design engineer, followed up with Robert Durkee of Ideas to Market (Austin, TX), a technology-transfer firm that brought EcoMass to market and owns the patent. LaValley and Durkee worked together to develop a shield that could be manufactured using conventional thermoplastic molding equipment.

"Robert Durkee helped us by designing and commissioning the molds for the part," says LaValley. "EcoMass composite has turned out to be the perfect answer to our needs." A mounting ring is molded into the part, removing several processes from assembly. "Best of all," says LaValley, "the radiation performance of the EcoMass material is excellent—zero rad meter at 16 in."

LaValley says that when all the costs of the material and its molding and production are considered, it saves the company 50% over the cost of using lead. "It took us less than half a year to switch from lead to EcoMass. That's six months for a total switch in material and approach, including part design, mold production, assembly training, everything."

The EcoMass composite incorporates tungsten, the heaviest of metals, as a filler. Xitec specified EcoMass NJ-96 TP, which has a specific gravity of 11 g/cm, equivalent to lead.

Consisting of powdered tungsten dispersed in a thermoplastic matrix, EcoMass provides radiation shielding and high-mass characteristics comparable to lead. The material combines tungsten's density and inertness, while exhibiting high yield strength and providing the processing benefits of a conventional thermoplastic material. The scrap from these composites is 100% recyclable at the molder and retains its properties through regrind and multiple heat histories.

EcoMass and other polymer-metal composites can be formulated using a variety of thermoplastic binders and filler compositions to tailor a product's density, heat-deflection temperature, tensile strength, impact strength, and flexural modulus, all to specific customer requirements. Currently, eight compounds are available, ranging in specific gravity from 6.0 to 11.0 g/cm.

The x-ray tube shield is now being used in Xitec's portable c-arm x-ray equipment, which is used in the medical and veterinary markets to view extremities and for podiatry and hand surgery.

Copyright ©2001 Medical Product Manufacturing News

Machine Designers Address Space, Validation Issues

Originally Published MPMN April 2001

EQUIPMENT NEWS: Packaging and Sterilization Equipment

Machine Designers Address Space, Validation Issues

There is no room for error in the production of medical devices, and that includes making sure they arrive at their destinations unharmed and sterile. In this section, packaging and sterilization products, including a compact gamma sterilizer and an array of heat sealing equipment, are described that can help you to achieve this goal.

Sterilization systems feature small footprints

A compact gamma unit supplied by MDS Nordion sterilizes batch loads of medical products in their final packaging.

A new small-scale irradiator available from MDS Nordion is designed to deliver radiation sterilization to batch loads of medical products in their final shipping packages. Simple, fast and economical, the Brevion irradiator requires only 30.5 ¥ 18.5 m of floor space. Leading-edge programmable logic controls make the Brevion easy to use. Gamma processing streamlines the final stage of the manufacturing process to eliminate harmful microorganisms. When validated process control procedures are used, products can be released for use immediately following irradiation.

An E-beam sterilizer developed by Titan Scan takes up less than 750 sq ft of floor space.

Using electron beams that produce little pollution, a concrete-shielded irradiator ensures the sterility of most disposable medical devices. The On-Site system from Titan Scan Technologies includes a linear accelerator, conveyance system, and computer interfaces. A remote computer tracks operations, performs parameter measurement, and produces dose-reporting documentation. Energy levels of 4­10 MeV are available, with special designs to fit individual production needs. The complete system can be installed in less than 750 sq ft of floor space.


Control system manages sterilization process

Compatible with new and existing sterilizers, a control system from ARS Enterprises allows increased manipulation and recordkeeping of the sterilization process. Among other functions, the Frontier 2000 controller allows a user to manage sterilization to limit thermal exposure for heat-sensitive products and to control utility lines at start-up and shutdown. Meeting all FDA CGMP requirements, the unit consists of an Allen Bradley 500-series PLC, a 16-color LCD, and a 40-column impact printer. A 10-key data pad with 12 preprogrammed function keys is used to input information. Monitoring and documentation of cycle parameters is performed by a 12-in. chart recorder. A thermal printer is available as an option.


Microprocessors add functionality to heat sealers

There are almost as many ways to seal packages as there are sealers. Heat sealing, however, has represented an area of significant development in the last year. Following are descriptions of a number of machines that use this technology in slightly different ways to safely seal medical packages.

A heat sealer from Van der Stähl Scientific Inc. incorporates a microprocessor that enables direct data capture via an RS-232 port.

Incorporating advanced monitoring systems to ensure seal repeatability in terminally sterile packaging, a rotary heat sealer handles most flexible medical packaging substrates at the rate of 10 pouches per minute. A unique microprocessor built into the MD-850 sealer from Van der Stähl Scientific Inc. allows direct data capture through an RS-232 port, and keeps the heating platens within ±2% of a set point between 80° and 200°C. If a set point is not met, the machine will not accept packaging. The low-profile stainless-steel unit also has a dot-matrix printer that can stamp letters, numbers, and regulatory symbols directly onto packaging. Changing the lot coding and sterilization date is a simple task, according to sterile packaging division director Charles Webb, because the "printer is easily programmed through the unit's microprocessor." The microprocessor also monitors calibration requirements, displaying a reminder message when necessary. The manufacturer performs the adjustments with a typical turnaround time of 24 hours.

Automatic safety gates are among the features of heat sealers developed by Packworld USA.

Two pneumatically actuated bar sealers promote safety by means of automatic safety gates that prevent activation if the user's fingers are too close. Manufactured by Packworld USA, the PW 3600 and 5200 sealers also have controllers that measure seal time, temperature, and pressure for FDA and NIST validation. A hard copy of the statistics for each cycle can be printed with an optional data unit. "The machines can make or seal virtually any plastic or plastic-coated material such as Tyvek, polyethylene, coated paper or foil, and laminated films," according to sales manager Joe Smith. Vacuum systems can be added to the stainless-steel units to purge pouches before sealing.

Sealing times and temperatures are digitally controlled on a two-station heat sealer offered by Alloyd Company, Inc.

A two-station heat sealer from Alloyd Company, Inc. has a sealing area of 14 ¥ 28 in. and a detent for precise positioning. Sealing time and temperatures of 32°­800°F are controlled digitally. The 2SM1428 sealer's nesting hardware is supported by solid aluminum bar stock, allowing it to withstand high pressures. Sealing gaskets are made of thick rubber to compensate for variations in the thickness of device trays. Two emergency stop buttons and a Lexan heater-plate door are among the safety features. The sealer occupies 19.5 sq ft of space, and has a pressure gauge on the incoming air supply. Options include a Teflon coating for the heater blocks and a thermocouple for sensing plug temperature.

Sealing equipment from Zed Industries Inc. features data storage capabilities.

A color touch screen operator-interface panel enhances the performance of a four-post sealer from Zed Industries Inc. The 15-TM sealer's interface has data-storage capabilities and allows "complete control of sealing parameters, fault diagnostics, job memory," and other factors, according to sales engineer Chris Cummings. The machine uses a ball-bearing shuttle system that automatically accepts, seals, and returns packaging to the operator. Compatible packaging materials include PVC, styrene, PET, Tyvek, foil, and card stock. A scratch-resistant Teflon-coated hot plate, greaseless bearings, and a low-air-pressure shutoff alarm are standard features. A coalescing exhaust filter or special plumbing for outside exhaust are also available. The sealer comes in an array of sealing sizes with a standard tray depth of 4 in.

A dual unit from All Packaging Machinery Corp. seals a range of materials while validating temperature, speed, and pressure.

A continuous dual heat sealer closes difficult materials with special heavy-duty wear-resistant Teflon bands. The VBSDH-8-10-V unit from All Packaging Machinery Corp. seals a variety of materials while validating temperature, speed, and pressure. Uniform pressure on all sealing surfaces creates consistent quality. Self-contained compressed air eliminates the need for external sources. Four digital temperature controls regulate each heating and cooling element. Instant pressure releases allow quick changeovers and cleaning of Teflon bands. Mounted on an adjustable stand, the unit can be used horizontally or vertically. Chrome-plated sealing assemblies and a stainless-steel chassis reduce wear.

Sealers from Belco Packaging Systems Inc. are suited for closing pouches in a cleanroom environment.

Designed for use in cleanroom environments, two sealers from Belco Packaging Systems Inc. close a variety of premade pouches using constant-heat jaws. The PM EL 18 and PM PLC 18 sealers have stainless-steel enclosures and seal bars measuring 18 ¥ 8 in. Seal heads are coated with Teflon to minimize maintenance time and costs. Four temperature-validation ports monitor the entire seal bar to ensure accurate process validation of seal temperature. The PM PLC 18 unit also features package setup memory, password protection, an air-system pressure validation program, and an alarm that disables when temperature or pressure fall out of specified tolerances. Both units can be outfitted for autoclavable sterilization and are available in other sizes.


Impulse sealer promotes integrity and safety

An impulse sealer with digital controls has numerous features to ensure safe and error-free operation. Supplied by Packaging Aids Corp., the Med Vac sealer's timer begins only when the preset seal temperature is reached to maintain seal integrity and consistency. An alarm activates whenever a parameter falls out of a preset range, halting operation until the start button is manually pressed. A lockable cover for the control box prevents access by unauthorized personnel. Other safety features include an emergency stop button and an automatic jaw-interference release system that prevents operation when the jaws are not fully closed. The seal jaws have independent on/off switches to accept a variety of pouch materials. External seal-parameter testers ease validation and calibration.


Hot-air sealer minimizes downtime

By eliminating Teflon-coated bands in its hot-air sealer, O/K International Corp. reports a reduction in downtime and replacement costs.

Meeting the requirements for FDA process validation, a variable-speed hot-air sealer does not use Teflon-coated bands, which minimizes downtime, replacement costs, and particulates according to the manufacturer. The Medical Supersealer from O/K International Corp. uses a PLC controller with touch screen to adjust sealing parameters and store product recipes. An Ethernet network connection provides continuous process monitoring, including data acquisition and logging. Seal pressure is air regulated, allowing complete system calibration. Plug-in thermocouple connectors and a seal-pressure interface ease standardization. Other functions include integral heater height measurement and automatic reverse.


Sealer for small packages incorporates printing system

Benchtop equipment supplied by Odessa Packaging forms, fills, and marks packages in one operation.

Specifically designed for small medical items like test kits, sutures, miniature devices, and medications, a combination packager and labeler forms, fills, and marks packages in one operation. The benchtop Smallpak Air 5 from Odessa Packaging integrates a heat sealer with a ribbon-saving 300-dpi printer that can produce graphic and written information. Operated via digital controls, the PLC-driven machine uses compressed air to make repeatable seals. Sealing speed, pressure, temperature, dwell times, and package length are completely adjustable. Service-recording and diagnostic functions are built into the touch-sensitive controls. Liquid-fill or gas-purge capabilities are available as options.


A unit offered by Newman Labeling Machines Inc. simultaneously applies tamper-evident security labels to both closure ends of a carton.

Labeler protects against counterfeiting and tampering

Adding security to pharmaceutical packaging, a stepper motor­driven labeler simultaneously applies tamper-evident security labels to both closure ends of a carton. The CTE 350 labeler from Newman Labeling Machines Inc. features an inspection system that detects label presence and permits only cartons with properly placed stickers to proceed. Airplane and reverse-tuck cartons are accepted at speeds of up to 350 cartons per minute. A continuous label-feeding design minimizes operator intervention and eliminates reel-changeover downtime. The stainless-steel unit uses a PLC to control carton speed.



Automatic labeler requires little user intervention

An automated system from Avery Dennison applies labels on cylindrical objects at rates attaining 100 labels per minute.

A fully automatic labeler from Avery Dennison applies bar-coded product ID labels to cylindrical objects at a maximum rate of 100 labels per minute. The Mini-Wrap labeler attaches identifying information to vials, ampules, jars, and other cylindrical items with diameters of 0.4­1.1 in. and a maximum height of 4 in. Replacing labor-intensive manual or semiautomatic machines, the machine can process an entire product batch after setup and loading without user intervention. A built-in control function rejects improperly labeled units and transfers suitable ones to an output compartment or conveyor. A control panel allows operators to change control functions, select from 24 programmable product banks, and display real-time production data.

Zachary Turke

Copyright ©2001 Medical Product Manufacturing News

Alloy Passes Biocompatibility Tests

Alloy Passes Biocompatibility Tests

An alloy from Hamilton Precision Metals is safe for use in implants.

After thorough investigation, a specialized alloy has been found to meet all criteria for implant compatibility as set forth under USP 24-NF 19 and ISO 10993 guidelines. Known as Havel, the material has passed independent, third-party testing for cytotoxicity, systemic toxicity, intracutaneous irritation, intramuscular implantation, skin sensitization, blood hemolysis, and pyrogenicity. Manufactured by Hamilton Precision Metals Inc. (Lancaster, PA), the alloy is available in foil or strip form with standard thicknesses of 0.0005–0.025 in. and widths to 7.5 in. Foils as thin as 0.000060 in. are also produced in up to 4-in. widths. During production, the foil is segregated from other materials to reduce airborne contamination.

Zachary Turke

Firm Eyes Success in Predicting Equipment and Device Failure

Firm Eyes Success in Predicting Equipment and Device Failure

What if you could predict one week ahead of time and with 80% accuracy that your assembly equipment will break down or that a component in your infusion pump is going to fail? Zero Maintenance International (ZMI; Chicago) has developed True Predictive Maintenance (TPM) to enable OEMs to do precisely that.

Based on pattern recognition technology, TPM extracts meaningful information from a machine's operational data and applies a family of solutions discretely or in combination to a machine population. ZMI contends that medical electronics firms, for example, could substantially reduce the 1.5% of estimated gross revenues they typically spend on preventive maintenance by implementing its system.

"TPM is built on our proprietary skill of knowing how and when to combine various methods drawn from applied artificial intelligence tools," says company president David Harris. While these technologies are well known in the military, robotics, and diagnostics fields, bringing them together in this application is novel, he says. "Academically, some things have been done in this area, but these attempts have all been engineering driven, rather than data driven. That makes a huge difference."

TPM brings together multiple streams of disparate operational data that many machines today automatically generate and flows them into a database. Initially "we had to learn what kind of data we wanted to look at and develop techniques to perform analyses quickly and to draw conclusions within an appropriate window of prediction," says Harris. Although the sequence and timing of various operating codes may appear infinite, a machine's patterns of operational data are finite in number, no matter how large that number may be, he adds. "TPM allows you to plumb the meanings of patterns in all of a machine's operational data."

David Harris is president of Zero Maintenance International, a company that has adapted pattern recognition technology for use in the prediction of equipment failure.

The benefits for device OEMs can be significant, according to Harris. He cites MRI equipment as a prime example. "Servicing an MRI unit may involve swapping out a part that costs thousands of dollars and requires the use of a couple of highly skilled engineers," Harris explains. "If you wait until the part fails, the downtime could result in the loss of substantial revenue." Nor do you want to keep a component costing $10,000 in stock, he adds. "If you are able to predict what will happen next week, that's very valuable information."

For sophisticated equipment, TPM provides benefits well beyond the scope of routine preventive maintenance programs, according to Harris. "If an x-ray tube is supposed to have a life cycle of 100,000 uses and the actual field experience ranges between 80,000 and 150,000, then mean time between failure is not a terribly useful instrument."

Noting that devices today tend to have onboard intelligence, Harris believes that regulatory bodies will increasingly demand that the available data be used to advantage. "In my opinion, once a company is able to apply TPM to improve the performance of its product in the field, to increase its uptime, or to prevent errors because they are now predictable, the regulatory bodies will start asking people who are not making use of this technology, 'Why not?' "

For a limited time, Zero Maintenance International is giving medical electronics OEMs complimentary access to the True Predictive Maintenance Criteria Evaluation Program. By assessing current machine data, the evaluation will help manufacturers to determine if their firm is a good candidate for TPM technology. Companies interested in finding out more should e-mail sberg@zmicorp.com.

Norbert Sparrow

Motherboard Complies with Medical Instrumentation Requirements

Motherboard Complies with Medical Instrumentation Requirements

An industrial motherboard is suited for medical instrumentation environments where system certification issues mandate that the product be available for many years. The ITOX VPCx, available from Itox Inc. (East Brunswick, NJ), is a form-fit-function replacement for the company's VPC motherboard that has been in production for nearly five years. According to senior vice president of sales and marketing John Mattlock, the new motherboard was designed "to be more powerful, have more features, and be as economical as its predecessor."

The VPCx features seven expansion slots, a built-in video controller, and a watchdog timer.

The VPCx uses National Semiconductor's Geode GXI low-power-consumption integrated processor for economy and cool operation. It features seven expansion slots that can accept full-length ISA cards with an industry-standard Baby AT format. The motherboard's compact size and large number of expansion slots make it suitable as an alternative to more expensive backplane system architectures. Improvements over the VPC include a built-in video controller, an integrated 586 processor that runs at 200 MHz, and a watchdog timer that automatically restarts the system when needed.

Katherine Sweeny

Manufacturing Capacity Increased at Eastman Chemical

Manufacturing Capacity Increased at Eastman Chemical

A liquid crystal polymer with good knit-line strength is engineered for thin-wall applications.

Eastman Chemical Corp. (Kingsport, TN) has modified its existing facilities to begin the production of 6.5 million lb of liquid crystal polymers (LCPs) annually. To meet expanding demand for high-quality polymers, the plastics manufacturer plans to use the new resources to produce an LCP specifically formulated for thin-wall applications. Marketed under the name Titan, this material has good knit-line strength and is heat resistant and flame retardant. Dimensional stability and low shrinkage make it suitable for complex electronic parts, medical instruments, dental trays, and ceramic replacements. A variety of low-warp and glass-loading grades will be available in lubricated and nonlubricated forms starting this month. Corporate officials estimate that Titan LCP will be marketed through the specialty chemicals and plastics wing after a recently announced corporate initiative to split the firm into two publicly traded companies takes effect.

Zachary Turke

Small-Diameter Alumina Fibers Can Be Used as Reinforcement for Medical Composites

Small-Diameter Alumina Fibers Can Be Used as Reinforcement for Medical Composites

The NanoCeram fibers from Argonide Nanomaterials have a diameter of just 2 nm.

Argonide Nanomaterials (Stanford, Florida) has developed alumina fibers with a diameter of just 2 nm, a large surface area of 500–600 m2/g, and aspect ratios ranging from 20 to 100. They are smaller than the size of a DNA molecule.

"These fibers are two orders of magnitude smaller than any other commercially available alumina and/or silicon carbide fibers, which are about 0.5 µm in diameter," says marketing manager Cindi Prorok.

20 nm

It is generally recognized that fibers with smaller diameters are more effective in strengthening metals, ceramics, or plastics. The NanoCeram fibers offer the potential for substantial increases in composite strength over previous fibers. They are also likely to form superior ceramic membranes and membrane reactors because of their higher surface area compared to the particulate powders used to produce membranes.

Applications for NanoCeram include use as a structural reinforcement for metals, plastics, ceramics, and membranes; as reinforcement for medical and dental composites; for ultrafiltration; and for electrical and thermal insulation.

Karim Marouf

Vincent Medical to Produce Syringes for Medrad

Vincent Medical to Produce Syringes for Medrad

Vincent Medical will manufacture disposable syringes for the Pacific market.

Responding to growth in the Asian medical market, Vincent Medical Manufacturing Company Ltd. (Hong Kong) has completed an agreement to produce disposable angiographic and tomographic syringes for Medrad Inc. (Indianola, PA) on a contractual basis. This agreement is demonstrative of Medrad's continuing commitment to the Pacific market. Vincent's 250,000-sq-ft regional manufacturing facility located in Dong Guan, China, is expected to enhance service and reduce shipping costs. A division of Vincent-Raya Company Ltd. (Hong Kong), Vincent Medical is an ISO 9002–certified manufacturer whose products are distributed worldwide. Production is expected to commence this year.

Zachary Turke

Researchers Put a New Twist on Carbon Nanotubes

Researchers Put a New Twist on Carbon Nanotubes

Working independently, two Japanese university research teams have developed similar methods for synthesizing carbon nanotubes with a coiled shape. First discovered in 1991 by Sumio Iijima, carbon nanotubes are fullerene-related graphite cylinders closed at both ends with pentagonal caps. These structures are normally produced using arc evaporation or laser vaporization of carbon molecules, resulting in straight tubes with one or more walls. Scientists at the Toyohashi University of Technology and the Osaka Prefecture University, however, have formulated a means of reacting a hot organic gas with a catalytic substrate that results in coiled nanotubes.

Carbon nanocoils have a broad range of electrical, thermal, and structural properties that may make them useful for a variety of applications. Among other functions, they could be used to keep small blood vessels open, emit electrons in flat-panel displays, and act as springs in micromachines. Because they can be opened and filled, the coils may also be used to absorb gasses and to block electromagnetic radiation. Both university groups plan to continue their research to discover ways of freely controlling the size of the coils.

Zachary Turke