| 摘要 |
A method and apparatus for feeding a polyurethane mixture suitable to form a thermally insulating layer inside hollow bodies, such as hollow walls of a refrigerator cabinet, freezer, display counter or insulating panel. A polyurethane mixture resulting from chemically reactive components (A, B), supplied by a high-pressure mixing device (18), is injected into a cavity (13, 47) of a hollow body (10, 40) extending in a horizontal plain. The mixture is injected at a first flow-rate (Q) and a first injection speed (V), to be poured into a first deposition zone (21) farthest from the injection point. Subsequently, the flow-rate and the injection speed of the polyurethane mixture are gradually reduced in a controlled manner, to be poured in successive deposition zones (Zn) towards the injection point of the polyurethane mixture, along a distribution strip (F), allowing the injected mixture to spread out throughout the cavity of the hollow body along isometric expansion lines. |
