Method of compressing man-made vitreous fibre web
According to the invention, there is provided a method of compressing an uncured man-made vitreous fibre web, the web having two opposed major faces. The method comprising the steps: passing the web along a path; and subjecting the web to thickness compression by applying compression to the two major opposed faces of the web. Compression of each of said major faces of the web is applied by passing the path between converging continuous or discontinuous compression surfaces. Further, the respective major face of the web that is being compressed is in contact with one of the converging compression surfaces, and said converging compression surface is inclined towards the path. Additionally, each inclined converging compression surface applies an amount of compression to the major face of the web with which the respective inclined converging surface is in contact, wherein the amount of compression applied to at least one of the two opposing major faces of the web is adjustable.
1. A method of compressing an uncured man-made vitreous fibre web conducted by a compression unit on a production line prior to entering a curing oven, the web having two opposed major faces, wherein the method comprises the steps:
passing the uncured web along a path; and
subjecting the uncured web to thickness compression, by the compression unit, by applying compression to the two major opposed faces of the uncured web,
wherein
compression of each of said major faces of the uncured web is applied by passing the path between converging continuous compression surfaces,
wherein
the respective major face of the uncured web that is being compressed is in contact with one of the converging compression surfaces,
wherein
each surface of the converging compression surfaces through which the path passes is inclined towards the path, providing an upstream end of each respective surface at a greater distance from the path than a downstream end of the respective surface, and compression is thereby applied to the two opposing major faces simultaneously,
and wherein
each inclined converging compression surface applies an amount of compression to the major face of the uncured web with which the respective inclined converging surface is in contact, wherein one surface is provided by a conveyor belt with at least two primary support rollers and at least one secondary support roller located between the primary support rollers, the position of the at least one secondary support roller being moveable towards and away from the path, the amount of compression applied to at least one of the two opposing major faces of the uncured web between the at least two primary support rollers is adjustable by moving the at least one secondary support roller.
2. A method according to claim 1 , wherein the web is a secondary web formed from a cross-lapped primary web, which primary web is a fibre web formed by collecting mineral melt fibres on a collector.
3. A method according to claim 1 , wherein the amount of compression applied by each inclined converging compression surface is proportional to an angle of incline of the respective inclined converging compression surface, and wherein the amount of compression is adjusted by altering the angle of the incline towards the path of the inclined converging compression surface that applies compression.
4. A method according to claim 1 , wherein both of the converging compression surfaces are formed of at least part of a conveyor belt that transports the web.
5. A method according to claim 1 , wherein each support roller that is moved has a smaller diameter than the other support rollers.
6. A method according to claim 1 , wherein each support roller that is moved has a diameter of about 0.10 metres (m) to about 0.30 metres.
7. A method according to claim 1 , where each support roller that is moved has a length of about 2 metres to about 4 metres.