Method and arrangements for continuous manufacture of building panels

A method of manufacture of building panels, performed using a continuous press arrangement having an upper rotatable inlet drum connected to an upper rotatable outlet drum via an upper continuous press belt and a lower rotatable inlet drum connected with a lower rotatable outlet drum via a lower continuous press belt;

• said upper and lower press belts configured to form a product path therebetween for feeding a product in a feeding direction in response to rotation of said drums;
• an upper press table and a lower press table each comprising a displaceable pressure cushion configured to facilitate a pressure zone extending along at least a portion of said path,
• wherein an angle (phi) is formed between the upper continuous press belt and the product at a position downstream of a center axis of one of the inlet drums in the feeding direction, and upstream of the pressure cushion,
• the method comprising:
• varying the angle (phi) by varying a vertical position of the upper rotatable inlet drum, wherein the continuous press arrangement is configured to vary the angle (phi) at least from 0.3 to 1.5 degrees by varying the vertical position of the upper rotatable inlet drum,
• feeding a product in the feeding direction to the product path of said continuous press arrangement, wherein the product comprises a core, a sub-layer and a surface layer on said sub-layer, the surface layer including a wood veneer, and
• passively displacing the at least one displaceable pressure cushions of the upper and lower press tables when the product is in the pressure zone,
• wherein the continuous press arrangement is configured to operate isobarically by applying constant pressure in the pressure zone.

A method of manufacture of building panels, performed using a continuous press arrangement having an upper rotatable inlet drum connected to an upper rotatable outlet drum via an upper continuous press belt and a lower rotatable inlet drum connected with a lower rotatable outlet drum via a lower continuous press belt;

• said upper and lower press belts configured to form a product path therebetween for feeding a product in a feeding direction in response to rotation of said drums;
• an upper press table and a lower press table each comprising a displaceable pressure cushion configured to facilitate a pressure zone extending along at least a portion of said path,
• wherein an angle (phi) is formed between the upper continuous press belt and the product at a position downstream of a center axis of one of the inlet drums in the feeding direction, and upstream of the pressure cushion,
• the method comprising:
• varying the angle (phi) by varying a vertical position of the upper rotatable inlet drum, wherein the continuous press arrangement is configured to vary the angle (phi) at least from 0.3 to 1.5 degrees by varying the vertical position of the upper rotatable inlet drum,
• feeding a product in the feeding direction to the product path of said continuous press arrangement, and
• heating the upper and lower press belts using the upper and lower rotatable inlet drums, respectively,
• wherein the continuous press arrangement is configured to operate isobarically by applying constant pressure in the pressure zone, and
• wherein the product comprises a core, a sub-layer and a surface layer on said sub-layer, the surface layer including a wood veneer.