IL41796A - A process for drying wet moulded articles - Google Patents

Claims (2)

1. CLAIMS 1. A process for drying moist moulded gypsum articles in sheet form comprising drying the article- in contact with, or by radiant heat from, at leas one heated surface held at a temperature at 90-l60°C.
2. 2. A process as claimed i claim 1 wherein the temperature of the heated surface or surfaces is continously reduced or reduced stepwise during the drying. 3· A process as claimed in claim 1 or claim 2 wherein the heated surface or surfaces is/are generally planar, 4. A process as claimed in any one of the preceding claims wherein the article is placed against a heated surface in contact therewith. 5· A process as claimed i any one of claims 1 to 3 wherein the article is interposed between a pair of heated surfaces. 6. A process as claimed in claim 5 wherein an article is interposed between each pair of a series of heated surfaces. 7. A process as claimed in claim 5 or claim 6 wherein the heated surfaces are generally planar and held in an upright position. 8. A process as claimed in any one of claims 5 to 7 wherein the or each article is in contact with one of a pair of heated surfaces and spaced apart from the other of the pair. 9· A process as claimed in any one of claims 5 to 7 wherein the or each article is spaced apart from both the heated surfaces of the pair between which it is interposed. 41796/2 V. - 13 - 10. A process as claimed in any one of claims 1 to 3 and 9 to 13 wherein the article is spaced apart from a heated surface by a distance of up to 70 mm. 11. A process as claimed in claim 10 wherein the distance is 0.2 to 20 mm. 12. A process as claimed in any one of the preceding claims wherein the or each article is continously moved during drying. 13· A process as claimed in claim 12 wherein the heated surface or surfaces is/are stationary and as drying proceeds the article is dried by a heated surface or surfaces at a lower temperature. 14· A process as claimed in claim 1, substantially as described herein with reference to any one of the aceompanying drawings. 15. Moulded gypsum articles when dried by a process as claimed in any one of the precedin claims* 16. Apparatus for drying moulded gypsum articles in sheet form by a process as claimed in claim 1, hich apparatus comprises a plurality of heating surfaces between which a pluralit of articles to be dried can be interposed, means for heating the said surfaces in use, and means for moving the heating surfaces from one heat supply point to another or for movin articles after drying away from the heating surfaces 17· Apparatus as claimed in claim 16 wherein a conveyor is provided for moving the articles away from the heating surfaces. 18· Apparatus as claimed in claim 16 or claim 17 wherein at least two sets of heating surfaces are provided which allow 41796/2 the articles to be removed during drying from one set at t a first temperature to a aecond set at a lower temperature than the first. 19. Apparatus as claimed in any one of claims 16 to 18 wherein the heating surfaces are generally planar and held in an upright position. 20. Apparatus as claimed in claim 16 f substantiall as described herein.