Spreading Head Basis Weight Control for Particle Mats
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for producing grit mats in wood-based panel production face challenges such as uneven basis weight distribution, material loss, and difficulties in handling and trimming, leading to production interruptions and suboptimal panel quality.
Innovation Solution
A mechanical guide device is used between the metering and spreading devices to partially displace and stabilize the grit material, allowing for adjustable basis weight distribution across the width of the grit mat, reducing material waste and improving edge quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If additional material tracks are placed on the grit mat in subsequent devices, then the basis weight profile can be differentiated, but production interruptions occur due to complex machines coming to a standstill
Solution Approach 1:
The basis weight profile is predetermined in the spreading head itself rather than being added later. The spreading head is designed with adjustable spreading widths that allow the edges to receive less material during the spreading process, creating the desired basis weight profile before the grit mat leaves the spreading head. This eliminates the need for subsequent intervention devices that would cause production interruptions.
2Manufacturing precision
If lateral movable adjustment elements are provided in the spreading head, then uniform weight distribution can be achieved, but the longitudinal edges suffer from vibration and quality deviations
Solution Approach 1:
The spreading head implements local quality control by allowing different sections of the spreading head to operate with different spreading widths. The edge areas are specifically adjusted to receive less material, creating a basis weight profile that compensates for edge losses during pressing. This localized adjustment maintains edge quality without requiring movement during operation.
3Manufacturing precision
If trimming devices are provided to remove excess edge material, then the grit mat quality is improved, but material loss increases and returned grit has hardened binder
Solution Approach 1:
The desired basis weight profile is created in advance during the spreading process itself, with edge areas receiving less material from the start. This preliminary action eliminates the need for subsequent trimming operations, preventing material loss and avoiding the problem of returning grit with hardened binder to the spreading process.
Data Source
Figure 1
Figure 2~4
Figure 5~8
AI summary
The invention relates to methods and an installation for producing a particle mat (7) from at least one layer of particles (9) on a continuously revolving forming belt (8) by means of at least one spreading head (1) during the pressing of the particle mat (7) in a press (22) to give a material board. The particles (9) are discharged as a material flow (24) with a substantially even metering weight per unit area (DFG) across a width (B1) at a right angle and with a length (L) in the direction of production (11) of the forming belt (8) by means of a metering device (15) and are spread onto the forming belt (8) across a width (B2) in an oriented and/or non-oriented manner by at least one spreader (14). At least one mechanical guiding device (5) between the metering device (15) and the spreader (14) moves the particles (9) in the material flow (24) at least to some extent substantially at a right angle to the direction of production (11) of the forming belt (8) and/or stabilizes the particles (9) in the material flow (24) to at least some extent in its movement in the direction of movement (12). The invention further relates to a particle mat to be pressed in a press (1400).