|As the following articles show, many injection molded parts in the building and construction market are small. Here, however, is one of the largest you'll find. It's a tank used in many Brazilian homes for storing drinking water. The tanks, in 500- to 1000-liter capacities, are molded in high-density polyethylene on Uniloy-Springfield structural foam machines, which can produce up to 50 tanks per hour. The plastic tanks are longer lasting, more hygienic, lighter in weight, and easier to install than the previously used concrete tanks.
Divining secrets and detecting trends in the housing market is a bit like reading tea leaves. What are the indicators that the market is sagging, rising, or hitting a plateau? Here are some clues: Housing starts for the first four months of 1999 are ahead of last year's pace, and the seasonally adjusted annual rate for this year beat 1998 by 2 percent (see Table 1). Money spent on residential repairs and improvements rose in 1998 by just 1 percent over the 1997 total of more than $118 billion.
The Freedonia Group (Cleveland, OH) predicts relatively mild 3 percent annual growth in injection molding construction demand through 2006 (Table 2). The company says pipe fittings present the best opportunity for this market, while plumbing fixtures, shower heads, faucet and shower handles, and lighting fixture diffusers are expected to grow at a slower pace.
Building and construction markets are typically dominated by extruded products, such as window stripping and vinyl siding. But molded offerings are making some headway with introductions such as the eco-shake shingle from Re-New Wood (Wagoner, OK), which is molded from recycled PVC and wood filler. Nailite International (Miami, FL) also offers a line of molded wood-like shake for exteriors, which is finding favor in severe weather locations.
Resin usage figures for 1997 from SPI indicate that ABS and SAN are popular in exterior products for weatherability (235 million lb), while polystyrene for indoor molded products rang in at 499 million lb. Other prominent resins include PVC, chlorinated PVC (CPVC), and ASA.
The TempRite division of BFGoodrich (Cleveland) produces extrusion and molding grades of CPVC. Customers use it to mold transition fittings-tees and elbows-for plumbing systems that compete with copper for hot and cold potable water systems in residential and commercial building. "We're fortunate because we provide a new material that replaces a traditional one," says Roy Harris, senior marketing manager. "Rather than relying on increases in housing starts, our growth comes from winning market share from copper pipe." In the '90s, TempRite has seen double digit growth. The CPVC system eliminates corrosion and the need for welding, along with the associated fire hazard. "In areas such as Florida we have taken over the market," Harris says.
TempRite customers also mold fittings and connectors for hotel and motel fire sprinklers. "The system requires insert molded fittings and connectors to adapt the sprinkler head into the CPVC piping," he adds, "and the plumbing system needs elbows or tees to allow pipe to be routed around the room." Fittings are connected to pipe via a solvent cement joining method.
Talc-filled PP enhances colorful window corners
The E-Z Corner is a patented window corner injection molded by Advanced Plastics Mfg. Inc. to match window trim and siding on houses. Produced in almost 300 colors, the corners have to withstand sun and weather exposure. Sold via retail outlets such as Home Depot, Lowes, and Menards, the E-Z Corner has doubled its sales every year for the past three years.
Polifil, a high-impact, 20 percent talc-filled polypropylene, is used to mold the corners. The material is compounded and supplied by The Plastics Group of America. It is supplemented with an antioxidant and two UV packages, one for sun blocking and the other for absorption to help the corners hold their color under direct sun exposure.
Advanced Plastics uses the base PP resin and adds all color at the injection molding machine. The consistency and stability of the natural-colored PP is critical to the company's ability to match colors.
"The product's success is largely due to the fact that it meets vinyl siding industry color standards," says Mark Habetz, owner of Advanced Plastics. "It's the only product of its kind on the market, and we anticipate doubling sales again in 1999."
For more information:
The Plastics Group of America
Phone: (800) 984-4874
Fax: (401) 767-2823
LCP helps this light shine
French manufacturer Giac SA produces this line of flush-mounted halogen minispotlights for use in kitchen and bathroom furniture, showcases, bookcases, and other similar locations. Dubbed the QuickLight, this easy-to-install fixture combines the spotlight, a base, a current supply, and cover. A simple 90Â° turn of the light removes it from the base.
The QuickLight has an integrated power supply system with an electronic voltage regulator that uses patented Regulux technology developed by FD Eclairage. This technology allows the lamps to be powered by a 230V current without a transformer and is the key to the miniaturization of the fixture. It also avoids heat buildup generated by transformers and doubles the bulbs' service life to 4000 hours by leveling out power supply leaks.
The material enclosing many of the key parts surrounding this innovative light are molded of Zenite LCP from DuPont. The material replaces heavier and more expensive ceramic sockets used in previous models. It was selected for its electrical insulation properties, dimensional stability, and high melting point (352C). The parts using the LCP include the spotlight's main casing, the bulb socket, and the three-part rotating bayonet mount set in the fixed base.
Giac also notes that the LCP's stiffness and dimensional stability eliminates warpage problems in the reflector cradle and in the high precision rotating parts of the bayonet mount, where the resin's low friction coefficient also proves helpful. Finally, the material's heat diffusion properties has allowed Giac to reduce the size of the QuickLight unit by keeping ventilation spaces to a minimum.
The QuickLight range includes 10W and 20W units in various finishes, as well as one-, two-, three-, and four-spot modular lighting fittings. Giac plans to add a 50W spot and a range of compact high-performance lighting systems to the current line, using the LCP for key parts.
For more information:
DuPont Engineering Polymers,
Phone: (800) 441-0575;
Fax: (302) 999-2311
PVC lends a hand (rail)
This Deco-Grip hand rail and wall protection system is comprised entirely of PVC, providing structural strength and easy installation, while still conforming to federal construction codes and ergo-nomic requirements. It is mounted to a wall to act as both a handrail and a bumper for such places as hospitals, nursing homes, office buildings, hotels, and other commercial buildings. Traditionally, most wall protection systems are comprised of both metal and PVC, making it difficult to achieve good structural strength while still conforming to construction codes.
The Deco-Grip, designed by Comus Design & Construction (Clarksburg, MD), is comprised of a main rail, which is extruded, and five molded components: the brackets, outside/inside corners, left/right returns, end caps, and internal connectors. Both the extrusion and molding compounds were supplied by The Geon Co. For molding, the chosen grade was M3700 compound, a PVC that provides rigidity, good colorability, and high gloss. It also met ASTM flame spread, smoke development, and impact resistance requirements.
Topcraft Precision Molders (Warminster, PA), which houses 41 molding machines ranging from 40 to 400 tons, does the injection molding for Comus. The five components are molded in family molds on several 120-ton Van Dorns.
For more information:
The Geon Co., Avon Lake, OH
Phone: (800) 438-4366
Fax: (440) 930-1428
Bearings made of nylon 6/6 endure stress in hinges
Every time a door opens and closes it takes a toll on the hinge bearing, and sooner or later the bearing will begin to wear down. Often this is the case with traditional butt hinges, which bear the weight of a door (ranging from 250 to 500 lb or more) on three 2- to 4-inch hinges. The stress on the frame and edge of the door can cause the frame to distort and pull the hinges out, eventually causing hinge bearings to crack. To meet this challenge Hager Cos. (St. Louis, MO) developed its Roton continuous-geared hinges, which run along the full length of the door and are said to endure 5 million door openings-twice as many as butt hinges offer.
The working force behind these aluminum hinges is their bearing blocks, which are injection molded with LNP's Lubriloy RL lubricated nylon 6/6 composite. According to Joanne Svejda, Hager's vp of Roton sales, the Lubriloy bearings last much longer than the acetal bearings used in previous versions of the hinge. The nylon 6/6's internal lubrication also provides a smoother and quieter operation, she says. The bearings fit into multiple milled cutouts along the length of the door, so when the hinge is mounted to the frame, the bearings evenly distribute the weight of the door. This design has enabled Hager to offer a lifetime warranty on the hinges.
Hager has the molding done out-of-house by Bucket Mold & Machine Co., also located in St. Louis.
For more information:
LNP Engineering Plastics
Phone: (610) 363-4500
Fax: (610) 363-4749
Blocks trade traditional glass for acrylic
Those funky glass blocks that first made their architectural debut several decades ago are handy for letting light into a room without all of the transparency that comes with traditional clear glass. The problem is, those glass blocks are heavy, which means their use is somewhat limited.
The block windows pictured here have the look of glass, but actually are molded of Acrylite H-15, an acrylic material supplied to manufacturer Hy-Lite Products Inc. (Beaumont, CA) by Cyro Industries. The blocks are 75 percent lighter than their glass counterparts and are 35 percent more energy efficient. "These blocks are so light there's no need for extra reinforcement," says Mark Moreno, Hy-Lite's sales and marketing director. "You have the beauty of glass block in places where heavy glass is not practical, with no worry of the frame sagging or cracking over time."
The blocks, which are used with vinyl and aluminum frames, are molded in two halves and welded to provide a watertight seal that prevents internal condensation and preserves the structural integrity of the window. Each block comes with nailing fins for installation, eliminating the need for masonry.
Mission Plastics in Cucamonga, CA molds the acrylic blocks in sizes ranging from 6 by 6 inches to 8 by 8 inches. They can be made into windows or panels up to 12 by 12 ft or in custom configurations that include rectangular, round top, arch top, and other shapes. They're available with one of three patterns: wave, cross rib, and frosted wave. Certain series are available in custom colors, and fiber-optic or tube lighting can be installed between the blocks to produce lighting effects. The blocks have reportedly undergone industry testing for strength, weatherability, and thermal efficiency. In accelerated 25-year tests, the blocks maintained 96 percent of their color.
For more information:
Cyro Industries, Rockaway, NJ
Phone: (800) 631-5384
Fax: (973) 442-6117