【文章內(nèi)容簡介】 r for the upper sheet layer.A double metal uncoiler is optionally added to the first one, allowing a minor number of production breakouts.(2) Loading coil carsLoading coil cars are used to position the sheet coils on the uncoilers.The coils can be set on the uncoilers even by using a forklift only on low speed production plants. For more sophisticated plants loading coil cars are necessary. Coil cars in steel structural framework fitted on an hydraulically driven sliding support. A V shaped platform is moved upward and downward by a hydraulic cylinder for coil loading.(3) Roll forming unitChoosing the right roll forming unit is dictated by both the types of panels to be produced and the financial investment on the plant.The configuration of the roll forming unit relies on the type of panels to be produced:corrugation depth, design of the profile, max width of the panel and detail joint designed of the panel (male/female。 secret fix joint。 cold store joint).(4) Preheating ovenThis preheating oven heats the profiled metal sheets to the right temperature to ensure the even and smooth expansion of the polyurethane mixture. The temperature control of the metal sheets is extremely important to ensure a high quality foamed panel. An unsuitable sheet temperature may cause a different foam density distribution and lack of adherence between polyurethane and metal sheets.A hotair circulation oven is the best to be used.(5) Metering machineA metering machine can be either low pressure or high pressure.The main benefits offered by a high pressure metering machine pared with a low pressure one are: Better mixing of the ponents。 Compact dimension of the mixing head resulting thus in: Positioning in restricted spaces。 Solventfree cleaning at end of production (environmental friendly solution)An hybrid system, posed by a lowpressure premix and metering in the polyol followed by a high pressure metering/impingement is a possible solution, but more expensive. In any case it allows the same advantages of both systems, including: High efficient monitoring of all working parameters。 Possibility to use, according to the present regulation in force, blowing agents alternative to Freon 11 thanks to dedicated instruments(6) Reactive mixture distributionA traverse provides a backward/forward movement to the mixing head thus enabling a smooth and even distribution of the reactive mixture all over the lower substrata, thanks to a wider range of nozzles thus avoiding splashes, air bubbles and foam superimposing during the rise phase.A robust structural support framework permits high reversion and translation speed of the mixing head according to the several production needs.A pouring plate is necessary in case of flexible substrata。 it must be heated, to give the substrata the right temperature for a correct adhesion。 moreover a suction under the plate is foreseen (through multiple holes), in order to ensure the best flatness of the substrata at the entrance of the laminator.(7) Flexible face uncoilers – unwinders.Depending on the manufacturing flexibility of the plant which can alternatively produce metal faced panels, metal/flexible face, or paper/paper, the plant can be equipped with uncoilers for flexible sheets both on the lower and upper layer. For high speed processes and for plants which requires nostop production, it is remended a system working with double unwinders (while one is working the other can be substituted and fixed), with rapid change device.(8) Double conveyor beltThe double conveyor belt contains the foam rise during the expansion and subsequent curing phase. Besides forming the press planes, both metal slats are interconnected in order to have a high load bearing chain plete with side rollingbearings.The time the panel stays on the conveyor depends on both raw materials used and preset panel thickness: for a 40mm panel thickness it takes around 2 3 minutes.OMS Group has built conveyor belts ranging from a minimum of 15m up to a maximum of 38m total length. The standard width is 1200mm, the distance between the two conveyors planes ranges from 20mm up to 400mm.The variation in thickness of the panel to be produced requires the insertion of calibrated spacer rings at open conveyors. The upper conveyor is movable by a series of hydraulic cylinders, while the lower one is fixed.The two conveyors are driven by two independent . motors fitted with dynamic speed reaction, each one plete with relative motor reducers in order to ensure a perfect speed synchronization between the two conveyors.(9) Panel profile changeover systemIt has been paid particular attention to the study of different possible solutions to minimize the changeover time by adopting simpler, functional systems. Metallic slats have special guides which allow the insertion of accurately machined aluminum slats having a different profile according to type of