July 6, 1998 Design News

Hot Products

Associate Editor Deana Colucci picks noteworthy fastening, joining, and assembly products

Epoxies deliver rapid cure

Loctite 3901 and 3902 epoxy adhesives deliver rapid curing in electronic assembly applications--up to six times faster than existing epoxy technology, says manufacturer Loctite. The adhesives achieve full heat cure in three minutes at 125C, and in two minutes at 150C. They are single-component epoxies formulated specifically for structural bonding of difficult-to-bond substrate and engineering plastics. The company says both products provide excellent chemical resistance and adhesion.

Connectors are liquid tight

Non-metallic right-angle connectors for Heyco-Flex I conduit and Heyco-Flex II tubing offer a liquid-tight connection. No disassembly is required to attach the conduit onto the connector or tubing. Simply push the conduit onto the connector ferrule, then hand tighten the domed sealing nut. Since the conduit is not threaded onto the ferrule (simply turn the conduit in a clockwise direction while pushing on the connector), no potential leak paths are created, and both the connector and conduit are reusable. In addition, the connectors feature a 90-degree bend that reduces the space required to route the conduit or tubing in the desired direction.

Adhesives enable faster UV cure

Dymax Corp. designed its Ultra Fast^TM adhesives to cure up to 300% faster than typical UV curing adhesives when exposed to visible and low-intensity longwave UV light. The company says the adhesives can cure completely in less than one second upon exposure to the light, forming durable bonds in the same time as those achieved with traditional UV adhesives and more costly, higher-intensity UV curing lamps. Dymax claims the faster cure times allow more rapid throughput with most lamps, extending the useful life of the light bulb, which in turn reduces cost by lowering the frequency of costly bulb replacement. The adhesives bond glass, plastic, metal, and many porous surfaces. Applications include use in glass and optical assembly, wire tacking, electrical potting, and sealing and encapsulation.

Dispensing system cuts production time

EFD Inc. says its VALVEMATE^TM 7000 dispensing system--which includes a controller, precision dispense valve, and pressurized fluid tank--can apply UV-cure adhesive in accurate, repeatable amounts without costly maintenance and downtime. The microprocessor-based system simplifies set-up, regulates valve operation, and provides precise deposit control. Valve-open time can be adjusted on-line in increments as small as 1 millisec without stopping the production line to reprogram a host computer or PLC. The system also features a diaphragm design and fast, clean cutoff that produce consistent deposits without bubbles or dripping. EFD says such controlled application ensures greater bond reliability and better control over cure time.

Epoxy suits medical applications

Master Bond Inc.'s EP30 Medical meets USP Class VI specifications and is suited for use in reusable and disposable medical devices. For bonding, sealing, and encapsulation, the low-viscosity, high-performance, two-component epoxy system cures at room temperature or more quickly at elevated temperatures. It has a convenient 4 to 1 mix ratio by weight and contains no solvents or diluents. Master Bond says the epoxy offers remarkable resistance to chemicals (including water, oil, and most organic solvents) and cold sterilants, as well as ETO and gamma radiation. It has a service operating temperature range of -60 to 250F.

Press runs faster, lasts longer

Penn Engineering & Manufacturing Corp. has re-engineered its PEMSERTERr Series 4 press system to run 35% faster than the previous model. Longer-life components have been added as well, along with user-friendly controls. The 6-ton manual press system has an 18-inch (45.7 cm) throat depth for a generous work area. It can install self-clinching fasteners in sizes #0 through 3/8-inch, and M2 through M10 in steel; and sizes up to 1/2 inch and M12 in aluminum or circuit boards. Penn says the system's pneumatic power delivers speed, consistency, and simple operation. The press also features a "point-of-operation" safety, and adjustable insertion forces from 500 lbs to 6 tons (2.2 to 53.3 kN).

Adhesive combines conductivity and viscosity

ABLEBONDr 8177 from Ablestik Electronic Materials and Adhesives meets the increasing demand for heat dissipation in reduced physical spaces by providing high thermal conductivity (3 W/mK). The rheological properties allow the epoxy to flow easily under components, making it suitable for bonding heat sinks or other heat-dissipation units to semiconductor devices. The manufacturer says ABLEBOND 8177 also exhibits excellent adhesion to large areas with a thin bond line. The adhesive is a blend of silver particles in a high-purity epoxy resin. It exhibits low chloride, sodium, and potassium contamination levels, enabling improved electrical reliability in environmental testing.

Adhesive protects in high temperatures

Thermeez^TM 7030 high-expansion adhesive protects steel, stainless steel, and aluminum in temperatures to 1,800F. The adhesive is fireproof and resists most acids, alkalies, solvents, corrosives, and electricity. It is asbestos free, has no harmful fibers, or objectionable odors, and requires no special treatment of the surface to which it's adhered. Thermeez 7030 cures at room temperature in 24 hours, or in 1 hour at 250F. Manufacturer Cotronics Corp. says the adhesive can be applied to most metals, ceramics, door and tadpole gaskets, and ceramic cloths; and adheres well to steel, stainless steel, aluminum, lead, and ceramic. The adhesive is suited for high-temperature applications requiring pressure-tight and fire-proof seals, wear resistance, and high expansion. Uses include exhaust systems, diesel engines, gas turbines, and heating plants.