Composite stops pump catastrophe
When a catastrophic failure occurred to one of J.R. Simplot's horizontally split case pumps, it could have caused severe case damage. Luckily, the pump had been modified and the original stationary wear rings and bushings lined with Xytrex® 451, a PEEK/-carbon fiber composite from EGC Corp. During the failure, when the boiler feed water hit about 220F and the discharge pressure stood at 580 psi, the material retained a sufficient amount of strength and lubricity to prevent the dynamic contact of adjacent metal components. "Xytrex 451 saved us $15,000 to $20,000 in repairs that would have been required if the pump had been fitted with the original metal parts," explains Darell Henderson, maintenance superintendent at J.R. Simplot.
High flow highlights this composite
LNP Engineering Plastics has introduced a high-impact, 30% glass-fiber-reinforced nylon 6 composite called Thermotuf® PF-1006 HI EP, for "Exceptional Processing." Containing a proprietary set of additives, the new composite is said to offer superior surface finish, higher melt flow, greatly reduced cycle times, and lower mold and stock temperatures than other standard nylon 6 resins. "This composite offers over 50% greater impact strength over a standard glass-fiber-reinforced nylon 6. And, because it is an easy flow material, molding cycle times are greatly reduced, resulting in higher productivity and significant cost savings for processors and OEMs," says Jamie Tebay, Thermotuf product manager.
Rotary vanes need no oil lubrication
OSHA continues to limit the amount of oil must that can be exhausted from pneumatic systems into the workplace. In response, Spaulding Composites Co. has introduced Spauldite® LF-1127, a formulation that eliminates the need for oil lubrication in such components as vanes in compressed-air-driven motors. The new laminate retains most of the advantages of other Spauldite vane materials, including dimensional stability, with the added feature of being internally lubricated. Initial test results in air-motor applications have been positive, with wear being much less than standard vane laminates.
Foam gets to core of composite problems
Isorca, Inc., a privately-owned contract R&D company for the composites industry, has introduced Alba-Core®, a matrix of glass microspheres bonded with just enough resin to make a robust material. Open spaces between the microspheres, as well as inside them, give this core a much lighter density than conventional syntactics, according to Isorca's Steve Katz. However, due to the way that the product is made, it becomes a closed-cell material, with minimal moisture absorption. The material can be made with a variety of thermoplastic or thermoset resins in flat sheets, put on a scrim like balsa, easily machined, or molded to shape.
Tubing targets medical instruments
Polygon Co. has announced the development of PolyMed Generation II composite tubing, available in a small (2 mm) diameter. Believed to be the first continuous reinforced composite tubing of this size, the tubing was designed to meet the stiffness requirements needed by the medical industry for minimally invasive surgery. Applications include: scissors, graspers, and electro-cauterizing devices. The tubing has enhanced physical and electrical properties, as well as better strength-to-weight ratios, than comparable metal instruments, according to Larry Horine, sales engineer.
Bridge benefits from composite beams
Tom's Creek Bridge (Blacksburg, VA) reopened to traffic recently as one of the first composite short-span vehicular bridges in the U.S. Composite beams made by STRONGWELL replaced the corroded steels beams supporting the bridge. The 8 36-inch beams comprised part of a joint development project with Georgia Tech for the government-sponsored Advanced Technology Program. Using a new optimized shape (twin webbed cellular I-section with transverse stiffeners), the bean is pultruded from a composite matrix of carbon/e-glass-reinforced vinyl ester resin. The design significantly improved the flexural modulus and torsional bending over the present fiberglass I-beam design, according to John J. Kesko, one of the project designers and an associate professor at Virginia Polytechnic Institute.
Composite bridges another gap
One of Europe's largest glass-fiber-reinforced plastic (GFRP) bridges opened recently in Kolding, Denmark. The Fiberline bridge project brought together several key sponsors, including: profile manufacturer Fiberline; resin supplier Jotun Polymer, the City of Kolding, and Owens Corning. Measuring 40 meters long and three meters wide, the bridge is predominantly designed for pedestrians, but will also carry bicycles, motorbikes, and snow-cleaning vehicles weighing up to five metric tons. The structure consists of 15 different types of pultruded profiles with a ratio of 60% glass fiber and 40% resin. The Owens Corning product used is roving 2043, 2500 tex. The bridge weighs about 10 metric tons--less than half the weight of a similar steel bridge.
System aids composite inspections
UCAR Composites Inc., a company that develops and provides precision tooling for the composite industry, has integrated the FaroArm®, a portable measurement arm designed with six- and seven-degrees-of-freedom, as well as FARO's AnthroCAM® 3D measure software, into its Integrated Manufacturing and Inspection System. This enables UCAR to conduct inspections and check surface profiles of aerospace tooling at vendor sites and analyze the collected data. Valisys® software integrates geometric dimensioning and tolerancing (GD&T) standards into the process. Each on-site inspection--formerly requiring at least three hours--now takes only a half hour. Because the FaroArm is portable, evaluations can be conducted earlier in the process, avoiding schedule delays.