Capable of being mounted directly over the throat of an extruder, the Maguire blender controls raw-material metering by weighing each recipe batch. Recipe ratios can be varied from 0.01 to 100% with simple thumb-wheel settings. In operation, the blender sequentially dispenses all ingredients, in their targeted recipe proportions, from separate hopper bins into a weigh chamber. From there the batch falls into a mixing chamber, then is fed directly into the processing machine. In subsequent batches, small corrections are made automatically.The key benefits provided by this “gain-in-weight” gravimetric system are:
· Reduced material consumption. The Maguire WSB exerts precise control over the metering of all materials into the extruder, including compound and costly colorants and additives. Automatically self-adjusting to compensate for variations in extrusion rate or bulk density, the blender maintains batch accuracy within 0.1%. This renders unnecessary such wasteful practices as “over-coloring” to compensate for process variations or for the unreliability of conventional feeding equipment.The resulting savings in material costs alone can enable a manufacturer to achieve payback on the cost of a Maguire WSB in less than twelve months, and for high-throughput operations, the payback time can be considerably shorter.
· Gain in operational efficiency. Essentially a means of compounding raw materials right at the extruder, the Maguire WSB frees manufacturers from the cost premium and inventory commitment associated with using pre-colored compounds, or from the labor and batch variations of pre-mixing raw materials off-line. The operational streamlining made possible by the Maguire WSB is particularly valuable for companies that supply customers on a just-in-time basis.· Improved quality assurance and accountability. In addition to the quality-control benefits of maintaining recipe consistency throughout a job run and (thanks to extensive built-in recipe storage capability) from one run to the next, the precise control over ingredients provided by the Maguire WSB is particularly important for manufacturers serving high-specification markets. The formulation data generated for each batch by the blender controller is readily accessible for meeting documentation requirements such as those for ISO-9000 operations.
· Expanded factory automation. The wealth of data generated by the blender controller has even broader potential for manufacturers looking to establish a system of plant-wide (or even multi-plant) monitoring and control. Maguire has developed various softwares for networking blenders and even for linking blenders with other machinery, translating between their different controller languages.Optimizing Electrical Performance through Color Control
Color, a necessity for visually coding wire and cable and, increasingly, for product identity as well, is in fact a necessary evil for wire and cable manufacturers. The pigments in color masterbatch can interfere with or degrade electrical performance. In the downstream test of dielectric integrity commonly performed on wire-coating lines, insulation with too much colorant of erratic color dispersion will fail the test by “sparking-out.”By increasing the accuracy and consistency of colorant dosing, the Maguire WSB enables wire and cable manufacturers to reduce colorant levels, not only to save costs but to enhance the electrical performance of the product in the spark test and in subsequent end use.
Because wire and cable manufacturers must frequently change colors, the Maguire WSB also represents an opportunity to boost productivity by speeding color changes. Particularly important in this respect are the automatic calibration capability of the blender, its ease of set-up, and the speed with which it can be cleaned out.First Low-Cost System for True Extrusion Yield Control
While the accuracy and consistency of the Maguire® Weigh Scale Blender (WSB) makes it possible to save on colorant cost and enhance electrical performance, wire and cable manufacturers can raise control to even higher levels with Maguire’s new LineMaster™ AC software. Adding only $5,000 to 8,500 to the cost of a WSB, the system provides true extrusion yield control, defined as uniform weight per length of product. This translates into consistent coating thickness, elimination of rejects, and raw-material economy.
The Maguire WSB is a gain-in-weight blender that sequentially dispenses ingredients, in targeted recipe proportions, from separate bins into a weigh chamber. In the LineMaster AC system, this batch is then fed into a loss-in-weight hopper mounted at the extruder throat. The hopper load cell provides updates on material consumption once every half-second to the WSB, mounted atop the hopper or on a floor stand. Using this input, LineMaster AC software simultaneously adjusts extruder throughput and hauloff speed to control yield. The high-speed responsiveness of the hopper makes the system effective even with frequent ramp-down / ramp up cycles, such as for reel changeovers.