GB845348A - Method and apparatus for forming fibrous casing - Google Patents

Abstract

845,348. Pipe making machines. JOHNS-MANVILLE FIBER GLASS Inc. Feb. 11, 1959 [March 3, 1958], No. 4712/59. Class 99(2). Pipe casings for heat insulation purposes are made by winding a glass fibre resin bonded mat around a mandrel and thus activating the binder whilst rotating the mandrel and applying pressure to the wound mat. Glass fibres are drawn from molten glass and are blasted by a flame from nozzle 15 to form a mat 23, binder being applied at 24. The mat is fed on to a conveyer 39 and from there on to a further conveyer 40. The first conveyer is driven by a motor 34 and a belt 77 which can be tightened by an air cylinder and piston arrangement 104. This causes a momentary reversal of the conveyer 39 putting the mat between the two conveyers 39 and 40 under tension. At this time a knife 65 is operated to sever the mat. The severed sections 119 are then wrapped round mandrels 160 rotatably mounted on a conveyer 132, a weighted roller 193 co-acting with the mandrel and progressing along with the mandrel to the dotted line position. By means of a cam (not shown) the effective weight of the roller can be varied during the co-acting period. An activating roller carried on links 275 provides heat to activate the surface layer of the casing, a similar cam arrangement providing control over constant pressure. Finally the mandrels are carried into a curing oven E where they are heated and subjected to pressure by the endless belt 322. The machine is controlled by a drum switch with a number of cam discs and mercury switches each activating a solenoid.