| 摘要 |
<p>Appts. for making polyurethane foam involves a conveyor belt on which he foam forming mix is carried, on a moving paper liner, through a tunnel provided with ducts and baffles to control flows of hot air above and below the belt transverse to the belt motion. The rate of air throughput and heat input and the effective length of the foam generation zone and the curing zones in the tunnel can be adapted to suit the reactivity of the foam reagents used. Esp. suitable for mfr. of continuous crust-free polyurethane foam blocks. The lower part of the tunnel controls the temps across and along the belt supporting the foam, including preconditioning of the return leg of the belt. Linked flow input splitting and outlet throttle valves keep the flow patterns dynamically stable during flow pattern alterations made automatically.</p> |
