GB190912126A - Improvements in or relating to the Manufacture of Artificial Stone Slabs and the like. - Google Patents

Abstract

12,126. Hartung, M. May 22. Processes; moulds; rolling-machines.-Relates to the manufacture of artificial stone slabs and plates of corrugated or other shapes, and preferably reinforced with wire netting, gratings, expanded metal, or the like, from an hydraulic binding-substance such as cement, and a fibrous material such as asbestos. A layer of cement and asbestos in a dough-like condition is placed in a moulding-frame f, having two flexible sides g, on a preferably waterimpermeable thin carrier b such as a sheet of imitation parchment paper. The frame f, with the carrier b, is laid either on a mould having a corrugated surface or on a corrugated metal sheet or matrix k, which is afterwards laid on the mould, and the layer of materials is pressed into the corrugations or cavities of the matrix, this operation being preferably effected by pressing one undulation after another, commencing from the middle undulation, by means of independentlyoperated dies h, Fig. 3, or rocking blocks l, Fig. 4. The reinforcing-insertion, which is preferably of expanded metal having inclined webs, and which may have been previously bent to the required shape of the slab, is then placed on the moistened surface of the pressed material. A second layer of cement and asbestos is shaped in a similar manner to the first, and, after adding an adequate amount of water, the first layer is tilted, with the insertion downwards, above the second layer by means of a supporting plate or frame, preferably consisting of parallel rods arranged at a distance apart equal to that between the corrugations, and made in two or more parts. The supporting-frame is then withdrawn, and the layers combine under pressure to form a finished slab with a reinforcing-insertion in the middle. When no reinforcing-insertions are used, the layer of materials first formed may be of such a thickness that, after being pressed into shape by means of dies or rollers, it only needs to be finally solidified in suitable moulds.