Production Line For Manufacturing Extruded Plates

Abstract

A production line for manufacturing extruded plates, comprises a conveyor for conveying a semifinished product, an edge cutting device for cutting off an edge area of the semifinished product to present a plate-shaped endless base profile, and a separating device for separating individual plates from the endless base profile. A distance (D) between the separating device and the edge cutting device in the conveying direction is dimensioned such that, between an average temperature T.sub.1 of the semifinished product during cutting of the edge area in the edge cutting device and an average temperature T.sub.2 of the endless base profile during separation, there is a temperature difference T.sub.1−T.sub.2 of 2 K≤T.sub.1−T.sub.2≤15 K. Due to distance (D) within an optimum temperature range, further processing of the cut off edge areas is essentially neutral in terms of installation space.

Claims

1. A production line for manufacturing extruded plates, in particular for panels for covering a surface of a room, comprising a conveyor for conveying a semifinished product produced as a plate-shaped endless profile along a conveying direction at a defined conveying speed; an edge cutting device for cutting off an edge area of the semifinished product which is lateral with respect to the conveying direction, so that in the conveying direction downstream of the edge cutting device, the semifinished product is formed as a plate-shaped endless base profile with a predefined base plate width extending transversely to the conveying direction; and a separation device for cutting off separated plates from the endless base profile, in particular along a cutting line extending transversely to the conveying direction, wherein a distance (D) between the separating device and the edge cutting device in the conveying direction is dimensioned in such a way that between an average temperature T.sub.1 of the semifinished product when the edge area is cut off in the edge cutting device and an average temperature T.sub.2 of the endless base profile during the separation process, there is a temperature difference T.sub.1−T.sub.2 of 2 K≤T.sub.1−T.sub.2≤15 K, in particular 4 K≤T.sub.1−T.sub.2≤10 K and preferably 5 K≤T.sub.1−T.sub.2≤8 K.

2. The production line according to claim 1, wherein, for the average temperature T.sub.1 of the semifinished product when cutting off the edge area in the edge cutting device 40° C.≤T.sub.1≤60° C., in particular 45° C.≤T.sub.1≤50° C. and preferably T.sub.1=47° C.±2 K is provided.

3. The production line according to claim 1, wherein cooling of the endless base profile between the edge cutting device and the separating device is provided exclusively by convection, in particular exclusively by natural convection.

4. The production line according to claim 1, wherein the edge cutting device provides a chipless cutting of the edge area from the semifinished product, in particular by means of a cutting tool configured as a cutting roller.

5. The production line according to claim 1, wherein the separating device provides a chipless cutting of the plate from the endless base profile with the aid of a cutting tool, in particular designed as a guillotine blade, wherein, in particular, the cutting tool of the separating device is configured to be co-movable at the conveying speed of the endless base profile in the conveying direction.

6. The production line according to claim 1, wherein a collecting container for collecting the edge areas cut off in the edge cutting device is arranged in the conveying direction between the edge cutting device and the separating device.

7. The production line according to claim 6, wherein the collecting container is arranged below the endless base profile in the direction of gravity, wherein in particular the endless base profile covers the collecting container at least to a large extent as viewed in the direction of gravity.

8. The production line according to claim 6, wherein the collecting container is connected to a return conveyor for conveying the contents of the collecting container into a recycling container, wherein in particular the recycling container can be connected to the extruder for the at least partial and/or temporary loading of an extruder for producing the semifinished product with an educt originating from the recycling container.

9. The production line according to claim 1, wherein at least one crushing device for crushing the edge area cut off as a strip-shaped endless profile is provided in the conveying direction between the edge cutting device and the separating device, wherein the crushing device is configured to feed crushed edge pieces produced in the crushing device from the cut-off edge area to a collecting container, wherein in particular the crushing device is provided in the conveying direction between the edge cutting device and the collecting container.

10. The production line according to claim 9, wherein a first crushing device for crushing a first edge area cut off at a first edge of the semifinished product and a second crushing device for crushing a second edge area cut off from a second edge of the semifinished product facing away from the first edge are provided, wherein both the first crushing device and the second crushing device are provided in the conveying direction between the edge cutting device and the collecting container, wherein both the first crushing device and the second crushing device feed the edge pieces produced in the respective crushing device to the same collecting container.

11. The production line according to claim 9, wherein the at least one crushing device is arranged below the endless base profile in the direction of gravity, wherein, in particular, the endless base profile covers the at least one crushing device at least to a large extent, as viewed in the direction of gravity.

12. The production line according to claim 1, wherein, downstream of the separating device in the conveying direction a cutting device for cutting the plate, in particular chipless, into individual panels, is provided in particular along at least one cutting line extending in the conveying direction, wherein a distance between the cutting device and the separating device in the conveying direction is dimensioned in such a way that between an average temperature T.sub.2 of the endless base profile during the separation in the separating device and an average temperature T.sub.3 of the plate (36) during cutting in the cutting device there is a temperature difference T.sub.2−T.sub.3 of 0 K≤T.sub.2−T.sub.3≤20 K, in particular 3 K≤T.sub.2−T.sub.3≤15 K and preferably T.sub.2−T.sub.3=5 K±2 K.

13. The production line according to claim 1, wherein the conveyor provides a conveying speed v.sub.1 of 4.5 m/min≤v.sub.1≤21.0 m/min, in particular 5.0 m/min≤v.sub.1≤8.0 m/min and preferably v.sub.1=5.5 m/min±0.5 m/min or v.sub.1=7.5 m/min±0.5 m/min.

14. The production line according to claim 13, wherein the conveyor exerts a compressive force pointing in the conveying direction at an initial region of the semifinished product which faces towards an extruder and is present in particular in a substantially pasty state, and a pulling force pointing in the conveying direction at an initial region of the semifinished product which faces towards the separating device and is present in particular in a substantially solid state, wherein the compressive forces and tensile forces acting are dimensioned in such a way that compression and stretching caused by thermal expansion effects during cooling of the semifinished product are compensated at least to a large extent.

Description

DRAWINGS

[0036] In the following, the disclosure will be explained by way of example with reference to the accompanying drawings based on preferred exemplary embodiments, wherein the features shown below can each represent an aspect of the disclosure both individually and in combination. In the drawings:

[0037] FIG. 1 shows a schematic principle representation of a production line; and

[0038] FIG. 2 shows a schematic top view of a semifinished product produced by the production line of FIG. 1.

DETAILED DESCRIPTION

[0039] The production line 10 shown in FIG. 1 comprises a storage container 12 and a recycling container 14, from which an extruder 16 can be supplied with an educt to be extruded. The extruder 16 can feed the educt via a wide slot die to a calender 18, so that downstream the calender a semifinished product in the form of a plate-shaped endless profile is present, which can be conveyed by a conveyor 22 in the conveying direction at a certain conveying speed. Here, the semifinished product 20 can be cooled during conveying, in particular by natural convection, wherein the local conveying speed of the conveyor 22 can be adapted in such a way that thermal expansion effects can be compensated by shrinkage of the material of the semifinished product. The semifinished product can be supplied from the conveyor 22 to an edge cutting device 24, which, at an average temperature Ti of the semifinished product 20, in particular with the aid of a rolling cutter 26, cuts off edge strips 28 so that an endless base profile 30 with straightened side edges and a defined base plate width transverse to the conveying direction remains on the conveyor 22. The endless base profile 30 is then fed to a separating device 32, which at an average temperature T.sub.2 of the endless base profile 30 cuts off separated plates 36, in particular with the aid of a guillotine blade 34 co-moved in the conveying direction. The average temperature T.sub.1 of the semifinished product 20 in the edge cutting device 24 and the average temperature T.sub.2 of the endless base profile 30 in the separating device 32 both lie within a comparatively narrow optimum temperature range in which the material of the semifinished product 20 and of the endless base profile 30 is still warm enough so that, due to the ductility still present, a mechanical resistance to penetration by a cutting tool is low, but is already hard enough so that the material does not remain sticked to the cutting tool or deforms too much under the shear stress occurring during the cutting process.

[0040] The actual width of the optimum temperature range is utilized to the extent that a distance D between the separating device 34 and the edge cutting device 24 is deliberately chosen to be greater than the minimum required, wherein the distance D is small enough to prevent excessive cooling of the endless base profile 30 by natural convection. This makes it possible to feed the edge areas 28, which have been cut off as strip-shaped endless profiles, to an associated first crushing device 38 and a second crushing device 40, respectively, in which the edge areas 28 can be crushed into edge pieces 42 of substantially the same size and fed to a common collecting container 44. From the collecting container 44, the edge pieces 42 can, for example with the aid of a return conveyor, be fed to the recycling container 14 and reused. Due to the deliberately larger chosen distance D, the crushing devices 38, 40 and the collecting container 44 can be accommodated in the conveying direction between the separating device 32 and the edge cutting device 24, in particular below the conveying device 22 and the endless base profile 30, in a manner that saves installation space.

[0041] As shown in FIG. 2, it is even possible to dispose the crushing devices 38, 40 and the collecting container 44 to a large extent, preferably completely, below the endless base profile 30. In this case, a certain elasticity of the edge areas cut off as strip-shaped endless profiles transversely to the conveying direction can be utilized. Alternatively, the crushing devices 38, 40 and/or the collecting container 44 may protrude laterally somewhat beyond the endless base profile 30.