Apparatus for producing plate-shaped bodies made of a mixture of plaster and fibrous materials

An apparatus for producing plasterboard from a mixture of plaster and a fibrous material, comprising:

• means defining a plasterboard production path;
• conveyor means for forming a moist mixture of plaster, fibrous material and water;
• spreading means along said path for spreading said moist mixture to form a mat;
• a first press downstream of said spreading means along said path for pressing said mat into a raw board with a pressure at least sufficient to compact said raw board into a coherent structure;
• an afterwetting station along said path directly downstream of said press and provided with first means for afterwetting an upper side of the raw board, second means for afterwetting an underside of said raw board, independently of said first means, and means for controlling said first and second means so that substantially independently controlled amounts of water are applied to the raw board from the upper side and from the underside thereof;
• a second press along said path downstream of said afterwetting station for afterpressing the afterwetted raw board with a pressure at least as high as a pressure applied by said first press;
• and
• a setting and drying station downstream along said path of said second press and provided with means for setting and drying the afterpressed raw board.