Market Focus: Industrial

Injectionmolded products are used in a variety of industrial applications,ranging from farm machinery, construction equipment, and machinetools, to firearms and chemical equipment. However, it is an arenathat molded plastics have made limited inroads into, showing onlya 2 percent hold on the market in 1998. This is mostly due toa demanding environment and the fact that aluminum and steel materialsare heavily entrenched in such applications.
To make matters worse, the outlook for growth is not exactly staggering,according to The Freedonia Group. Injection molded plastics demandin industrial applications is projected to increase less than1 percent annually through 2003 to approximately 300 million lb,reports the agency. Lackluster prospects are based on saturatedindustrial applications for components such as washers, gears,and pulleys.
High-density polyethylene is the dominant molded plastic usedin industrial applications, accounting for more than 35 percentof the total, says the agency. However, Freedonia expects declinesin demand to 105 million lb in 2003 due to demand for higher-performingmaterials and competition from other resins such as nylon.
Nylon, in fact, is expected to show the best growth through 2003,expanding more than 3 percent annually to 35 million lb. Firearmsshould represent a growing market for nylon because of demandfor more durable, lighter, and lower-cost materials.
Also, the U.S. Army is investigating the use of copper-jacketedbullets that incorporate a molded, tungsten-filled nylon in placeof the current lead/antimony alloy core, reports Freedonia. Thisconversion, which saves money and eliminates toxic lead fumesand residue, could be a big boost as the military buys between200 and 300 million rounds annually.

VALVES MADE FOR LESS
IN SWITCH TO PLASTICS

Looking for a way to produce aless expensive product, Peter Paul Electronics of New Britain,CT explored the option of redesigning its Series 40 solenoid-operatedvalve. The valve is used in humidifiers, pneumatic automationsystems, and beverage dispensers, among other types of equipment.Several components make up the part: a solenoid assembly, a valvebody, and a plunger. Before the redesign, the assembly was encapsulatedwith thermoset epoxy and the valve body was made of machined brass,stainless steel, or aluminum.
With input from DuPont, which included testing plaques and designand tooling suggestions, Peter Paul switched to plastic. Encapsulationfor the solenoid assembly (see photo, second item from the right)is now made of Rynite PET. The coil bobbin (far left) is alsomolded with Rynite, or, for food or beverage equipment, Delrinacetal. The valve body (far right) is made of Delrin.
The valve works like this: When the solenoid coil is energized,a spring-loaded, elastomer-tipped plunger is drawn away from anintegral seat in the valve body, allowing fluid to flow throughthe unit.
Several elements in the molding process were removed by switchingto plastic in the encapsulation. "Peter Paul got much shortercycles, eliminated VOC [volatile organic compound] emissions fromepoxy, and eliminated secondary finishing," says Tom Pellegatto,senior design engineer for the molder. The new design also allowedfor the integration of a support bracket in the encapsulation.In addition, the inner diameter of the bobbin now guides the valve'splunger, instead of a precision-welded metal assembly incorporatinga nut, a guide sleeve for the plunger, and an end stop.
The valves are available with .0313- to .125-inch orifices andare rated for service pressures up to 250 psi. For pneumatic controlapplications, a three-way version is made with a port at the topto exhaust air from downstream cylinders when the valve closes.
DuPont Engineering Polymers, Wilmington, DE
Phone: (800) 441-0575; Fax: (724) 514-9494
Web: www.dupont.com/enggpolymers;E-mail: [email protected]

PCLENDS SCANNER NEW LOOK

The futuristic look of this laserbar code scanner belies its true function. Still, it must withstandthe rigors of the retail environment. The MS9500 Series Voyagerretail scanner manufactured by Metrologic Instruments Inc. (Blackwood,NJ) is a single-line, handheld device that must tolerate aggressiveuse. Because impact resistance is important to the design, whichincluded a number of weldlines, Metrologic chose Xantar FC 23UR polycarbonate from DSM Engineering Plastics for the housing."The higher molecular weight of this material makes it tougherthan many other available resins, which became evident in ourdrop tests," says Tom Carullo, a Metrologic engineer. DSMreports that Xantar provides up to twice the resistance to impactstresses as other PC/ABS alloys, especially at colder temperatures.
UL 94 V-0 flammability, easy processing, and high aesthetic standardswere also important. The scanner housing is molded by Sunion ProductsLtd. in China and comes in various shades of gray.
DSM Engineering Plastics Inc., Evansville, IN
Phone: (800) 333-4237; Fax: (812) 435-7702
Web: www.dsmep.com; E-mail:[email protected]

 

PC,COPOLYESTER ALLOY GIVES TOUGHNESS TO FLASHLIGHT LENS

Industrial and construction workerswho buy flashlights generally look for one that won't fall apartthe first time it hits the ground. Rayovac Corp.'s (Madison, WI)newest industrial flashlight is designed with toughness in mind,as well as bright light. Ergonomically designed to fit the hand,the new design incorporates a krypton bulb and prismatic reflectorfor strong, white light; it stands up to toolbox abuse and hasa lifetime warranty to prove its durability.
Because the components must resist impact, heat, chemicals, andscratching, the manufacturer chose Eastalloy DA003 from EastmanChemical for the lens. "Rayovac industrial flashlights aredesigned to work under conditions that would kill normal flashlights,so we must test the resins we select very carefully," saysJim Neyer, program manager for lights at Rayovac. The polymeris a blend of polycarbonate, which provides impact toughness,and copolyester, which gives the lens chemical resistance.
Rayovac had been using Eastalloy for 10 years in its industrialflashlights, and chose it again for the new flashlight becauseit met the four resistance factors and provided good clarity.It also offers dimensional stability and low shrinkage rates,say Eastman sources.
The body of the flashlight is made of Montell's 8623 polypropylene.Amtec Molded Products (Rockford, IL) molds the lens and housing.
Eastman Chemical Co.
Kingsport, TN
Phone: (423) 229-4853
Fax: (423) 229-8595
Web: www.eastman.com
E-mail: [email protected]

Wafer wand holds semiconductors
safely with PAEK

Handling semiconductorwafers can be a tricky business. Some use metal tweezers, butthese can scratch the surface, creating particles that contaminatethe wafer. This wafer wand, distributed in the U.S. by NetMotion(Fremont, CA) and molded by Fluoro Mechanic Co. Ltd. (Tokyo, Japan),is designed to handle the wafers softly and firmly without contaminatingthe surface.
Because it has few trace elements that could contaminate the wafer,Peek polyaryletherketone (PAEK) from Victrex was selected forthe tips of the wand. "The area that contacts the wafer surfacesis optically polished to reduce surface particle counts,"says Van Le, marketing manager for NetMotion. This polish alsohelps the wand adhere to the wafer.
The PAEK was chosen for its corrosion and abrasion resistanceas well. Le notes its ability to handle wafers up to 12 inchesin diameter, and high continuous service temperature-an importantproperty when handling semiconductors, which are often processedin a high-temperature environment. Another key element of thePAEK is its carbon reinforcement. "The addition of carbonfiber makes the wafer wand ESD safe," Le explains. "Evenminute amounts of static electricity can damage electrical circuitson the wafer and result in major economic losses."
Victrex USA Inc., West Chester, PA
Phone: (800) 842-8739; Fax: (610) 696-5702
Web: www.victrex.com

Crystallizednylon cuts
cycles in pipe fittings

When a molder of plastichose and tube fittings for commercial, industrial, and agriculturalapplications tried to reduce cycle times, it ran into trouble.Thogus Products Inc., based in Avon Lake, OH, found that incompletelycrystallized parts were being pushed out of the mold too early.Knockout pins, pushing too-soft plastic, punched unwelcome holesin the part, rendering them unusable.
The solution to this problem came in the form of an additive fromM.A. Hanna Engineered Materials called Zip. This highly lubedand nucleated compound, when added to a base resin, acceleratescrystallization, solidifying parts faster. "After samplingthe [Zip] package in a number of tools, we discovered that everythingran much better," says Walter Gus, vp of manufacturing atThogus.
By nucleating the nylon 6 part (made of Nymax 600 A and Zip 39),Thogus found that crystallization occurred more quickly, settingup the component faster. The result was less postmold shrinkageduring cooling, and reduced cycle times since parts could be ejectedat higher temperatures.
Thogus' products include fittings for hoses, connectors, tees,elbows, reducer connectors, caps, bonnets, and plastic tubes.They replace brass fittings in some medium- and low-end applicationswithout high burst and pressure requirements.
M.A. Hanna Engineered Materials
Norcross, GA
Phone: (800) 729-8025
Fax: (770) 243-7020
Web: www.mahanna.com

Insulatorblocks water and environmental hazards with TPE

Dead-end composite insulators areused in power distribution towers to isolate electrical current.Weighing just 1.7 to 2.3 lb, this component from molder GLP Hi-TechPower Products Inc. (St.-Jean-Sur- Richelieu, PQ) consists ofcircular sheds that are compressed between a .75-inch-diameterfiberglass rod, overmolded with a thermoplastic elastomer, andcapped on both ends with manually affixed, forged steel fittings.Requirements for the insulator include longevity, flammabilityresistance, chemical resistance, and hydrophobicity. The TPE chosenand developed for the overmolding and circular sheds was DytronXL from Advanced Elastomer Systems. Its good electrical properties,including tracking resistance, and its ozone resistance also factoredinto its selection over silicone rubber. The insulator is availablein four sizes, ranging in length from 13.1 to 22.6 inches.
Advanced Elastomer
Systems LP
Akron, OH
Phone: (800) 305-8070
Fax: (330) 849-5599
Web: www.aestpe.com

 

Acetal,ultrasonic welding bring turbine to life

The next time you'rein the back yard watching your Polaris Pool Systems automaticswimming pool cleaner go through its paces, remember that theturbine helping the device keep the water clean may be like theone pictured here. Molded of acetal, it's injection molded andassembled with the SureWeld 20 ultrasonic welder from Sonobond.
Tim Herlehy, vp of manufacturing at Polaris (Vista, CA), saysthe company was experiencing jam-ups caused by loose-fitting bearings."When the bearings were press-fit into the turbine wheel,they just weren't consistently tight enough," Herlehy says.Welding bonded the materials together, creating one unit. "Nowthe bearing doesn't move within the assembly, so the jamming problemhas been eliminated," he says. Average weld time for thisapplication is .3 to .4 second.
Sonobond Ultrasonics
West Chester, PA
Phone: (610) 696-4710
Fax: (610) 692-0674

Cover keeps electrical parts dry

Thisweather-proof cover for flanged electrical inlets and outletsmakes a tight seal in harsh environmental conditions. The WP1,molded by Marinco Specialty Wiring Devices, is intended for power-inand power takeoff panels on industrial vehicles and machinery.Suitable for wet environments, the cover comes in gray, black,or yellow and is molded from Lexan glass-filled polycarbonate,supplied by GE Plastics.
Marinco says it designed these covers in-house as a variationof existing devices produced by the company. Peter Deutsch, vptooling and design, reports only one challenge presented by thetool after it was delivered: Several limit switches were neededbehind the side-pulling cores to prevent the tool from damagingitself on opening.
GE Plastics
Pittsfield, MA
Phone: (800) 845-0600
Web: www.geplastics.com
E-mail: [email protected]