Building or constructional material

• US 3,914,359 A
• Filed: 04/04/1973
• Issued: 10/21/1975
• Est. Priority Date: 01/04/1971
• Status: Expired due to Term

• Current Assignee: Dryflow Limited
• Original Assignee: Christopher Graham Bevan
• Inventors: Bevan, Christopher Graham
• Primary Examiner(s): Griffin, Ronald W.
• Application Number:
  US05/347,904
• Time in Patent Office: 930 Days
• Field of Search: 264/45,333,42,DIG.7,DIG.57,DIG.43 260/2.5B
• US Class Current: 264/45.3
• CPC Class Codes: B28B 1/521 from dry mixtures to which a setting agent is applied after forming B28B1/526, B28B1/527 take precedence
• CPC Class Codes: B28B 23/0087 Lightweight aggregates for making lightweight articles
• CPC Class Codes: B28B 3/2636 using means for co-extruding different materials
• CPC Class Codes: B28B 7/42 for heating or cooling, e.g. steam jackets , by means of treating agents acting directly on the moulding material
• CPC Class Codes: Y10S 264/07 Binding and molding cellular particles
• CPC Class Codes: Y10S 264/43 Processes of curing clay and concrete materials
• CPC Class Codes: Y10S 264/57 Processes of forming layered products

Abstract

A method of making a building panel having a central layer of expanded polymer beads optionally mixed with liquid setting powder and outer layers of fibre-reinforced liquid setting powder. The constituents are introduced in a dry state in layers into a mould with the beads partially pre-expanded and then steam is caused to permeate through the dry constituents to provide heat for fully expanding the beads and liquid for activating the powder so that expansion of the beads causes the constituents to coalesce into a compacted product which can be rapidly demoulded.

Claims

1. A METHOD OF FORMING A PANEL PRODUCT FROM CONSTITUENTS INCLUDING A MIXTURE OF LIQUID SETTING POWDER AND A FIBROUS REINFORCING MATERIAL, AND PARTIALLY HEAT-EXPANDED CELLULAR BEADS OF A HEAT-EXPANSIBLE POLYMER, SAID METHOD COMPRISING INTRODUCING SAID CONSTITUENTS IN A DRY, FLOWABLE STATE INTO A MOULED IN LAYER INCLUDING A FIRST LAYER COMPRISING SAID POWDER AND FIBER MIXTURE, AND A SECOND LAYER COMPRISING SAID BREADS, WHILE CONFINING THE INTRODUCED CONSTITUENTS WITHIN THE MOULD, PERMEATING THE CONSTITUENTS WITH STEAM, BY SAID PERMEATING SIMULTANEOUSLY MOISTENING THE POWDER AND HEATING THE BEADS, AND BY SAID MOISTENING, EFFECTING SETTING OF THE POWDER, AND BY SAID HEATING, SIMULTANEOUSLY EXPANDING TH BEADS TO APPLY INTERNAL PRESSURE ON ALL OF THE CONSTITUENTS INTO A MOULD, WHICH PRESSURE COMPACTS THE CONSTITUTENTS INTO A COHERENT MASS FORMING SAID PANEL.

2. The method of claim 1 wherein said beads are partially heat expanded to about 30 per cent of their total expansion before introduction to said mould.

3. The method of claim 1 wherein permeating of the constituents with steam takes place from within the mould.

4. The method of claim 1 wherein said layers are introduced into said mould while flowing in vertical columns.

5. The method of claim 4 wherein the powder and fibre mixture is prepared by fluidizing the powder flowing in one vertical column and introducing the fibre into the vertically moving column of fluidized powder.

6. The method of claim 4 wherein said columns comprises outer columns containing said powder and a central column containing beads and wherein pressure is applied to said central column to prevent inward collapse of said outer columns.

7. The method of claim 6 wherein powder is allowed to infilrate into the central column while said pressure is maintained on said central column to produce a combined bead and powder central panel layer.

8. The method of claim 1 wherein the layers are introduced into the mould while flowing in vertical columns, and said constituents are moved continuously through said mould at a controlled rate wile said steam is caused to permeate therethrough.

9. The mithod of claim 8, wherein the rate of movement of said constituents through said mould is controlled by controlling the rate of movement out of the mold of a compacted, cohered portion of said constituent.

10. The method of claim 1 wherein after steam permeation the mould is allowed to cool before removal of said compacted coherent mass.

11. The method of claim 10 wherein sufficient additional moisture is applied to said first layer after removal from the mould to complete hydration of the powder.

12. A method of forming a panel product from constituents including a mixture of liquid setting powder and a fibrous reinforcing material, and partially heat-expanded cellular beads of a heat-expansible polymer, said method comprising introducing said constituents in a dry, flowable state into a mould in layers, including a first layer comprising said powder and fibre mixture, a second layer comprising said beads, and a third layer also comprising said powder and fibre mixture, with said second layer sandwiched between said first and third layers, while confiniNg the introduced constituents within the mould, permeating the constituents with steam, by said permeating simultaneously moistening the powder and heating the beads, and by said moistening, effecting setting of the powder, and by said heating, simultaneously expanding the beads to apply internal pressure on all of the constituents within the mould, which pressure compacts the constituents into a coherent mass forming said panel.

13. The method of claim 12 wherein said second layer contains said beads mixed with liquid setting powder.