D simpson

Claim 1

IN APPARATUS FOR FORMING A CONTINUOUS STRIP OR SHEET OF ASBESTOS-CEMENT COMPOSITION OR OTHER LIKE MATERIAL, THE COMBINATION OF A FIRST FORMING MACHINE INCLUDING A TANK CONTAINING A WET MIX OF SUCH MATERIAL, A HOLLOW CYLINDRICAL DRUM ROTATABLE IN SAID TANK AND HAVING A POROUS CYLINDRICAL WALL A PORTION OF THE PERIPHERY OF WHICH IS DISPOSED BELOW THE MIX LEVEL IN THE TANK WITH THE INTERIOR OF THE DRUM SUBJECT TO ATMOSPHERIC PRESSURE, A PERFORATED SCREEN BELT PARTIALLY ENCIRCLING SAID DRUM IN CONTACT WITH SAID PORTION OF THE PERIPHERY OF THE DRUM, AND MEANS FOR REMOVING AT LEAST A PORTION OF THE WATER WHICH PASSES FROM THE WET MIX INTO THE INTERIOR OF THE DRUM THROUGH THE BELT AND SAID POROUS WALL, THE PRESSURE DIFFERENTIAL DUE TO THE STATIC HEAD OF THE WET MIX AT ONE SIDE OF SAID BELT AND ATMOSPHERIC PRESSURE AT THE OTHER SIDE OF SAID BELT BEING SUCH AS TO PRODUCE A PRELIMINARY FILM OF SAID MATERIAL OUT OF THE WET MIX ON SAID BELT WITHOUT FORCING SAID MATERIAL INTO THE INTERSTICES OF THE BELT; A SECOND FORMING MACHINE INCLUDING A TANK CONTAINING A SECOND WET MIX OF MATERIAL AND HAVING AN OPENING THEREIN TO THE ATMOSPHERE, A HOLLOW CYLINDRICAL DRUM ROTATABLE IN SAID TANK AND HAVING A POROUS CYLINDRICAL WALL A PORTION OF WHICH IS DISPOSED BELOW THE MIX LEVEL IN THE TANK, SAID BELT ENCIRCLING AND ENGAGING SAID PORTION OF THE PERIPHERY OF THE DRUM AND EXPOSING ANOTHER PORTION OF SAID PERIPHERY OF THE DRUM THROUGH SAID OPENING, MEANS FOR RAISING THE PRESSURE IN THE TANK ABOVE THE MIX SUBSTANTIALLY ABOVE ATMOSPHERIC PRESSURE INDEPENDENTLY OF THE STATIC HEAD OF THE MIX, AND OTHER MEANS FOR REMOVING AT LEAST A PORTION OF THE LIQUID WHICH PASSES FROM THE SECOND WET MIX INTO THE INTERIOR OF THE DRUM, WHEREBY AN ADDITIONAL LAYER OF MATERIAL IS DEPOSITED ON SAID PRELIMINARY FILM FROM SAID SECOND MIX.