| 摘要 |
<p>1,130,598. Extruding tunnelled sheeting. IMPERIAL CHEMICAL INDUSTRIES Ltd. 14 April, 1967 [25 May, 1966], No. 23405/66. Heading B5A. [Also in Division E1] A sheet of thermoplastic polymeric material comprising face layers interconnected by struts is made by feeding polymer at 2 to a sheeting die 1 and extruding the material from the adjacent orifice around strut-forming mandrels 10, the struts so formed being given a corrugated form along the length of the sheet by transverse oscillation of the mandrels. Such sheeting may be used as a building material. The mandrels are mounted on a bar which extends outside the die and is connected by a link 9 to a wheel 8, see also Fig. 1 (not reproduced), and are adjustable longitudinally, individually or otherwise, so that tapered ends 14 create different strut thicknesses, Fig. 3 (not shown). The lips of the die may be adjusted by means not shown to vary the thickness of the sheet. The sheet is cooled internally by air admitted via inlet 15 and transmitted to the sheet via conduits 13 in the mandrels and is cooled externally by aircooled chambers (17), Fig. 2 (not shown), which preferably have porous contact plates (19), e.g. of sintered bronze. The external cooling may alternatively be effected by water bath, chilled rolls or air blowers. The sheet may be cut into lengths as at (5), Fig. 1 (not shown), downstream of draw-off means (6). Numerous thermoplastic polymers are mentioned, those specially preferred being polyethylene, polypropylene, PVC, polymethyl methacrylate, poly 4-methyl pentene 1 and high molecular weight polyamides and polyesters. The polymer may be foamed and additives such as fillers and reinforcing fibres may be incorporated.</p> |
