Laminated timber assembly: The winner in open and pressing time – now it stands at about 1:1

Detmold.- Even before the LIGNA opens, Jowat AG is sending a winner into the race. The formulation of this adhesive was adapted for processes that are characterized by very large batches (high number of pieces), or where large elements are bonded in the assembly of laminated timber panels, composed of laminates of timber or plywood. The parameters of this adhesive allow long processing times during adhesive application, and comparatively short pressing times. As standard for the bonding of laminated timber, the ratio of open to pressing time depends on several factors: When the moisture content of the wood is 12 %, the glue line is 0.1 mm thick, and the temperature is 20 °C, the resulting ratio of open time to pressing time will amount to about 1:1 – approximately one hour of time for adhesive application and feeding of the press, with a pressing time of roughly 75 minutes. These parameters make processing much more flexible: They open up more working time where it is necessary for quality reasons, and shorten press times where the productivity can be raised and energy savings can be generated. The positive result is that process costs are optimised.

Until now, the ratio between open and pressing time was around 1:3 to 1:4. As a result, the time remaining for adhesive application on large-surface laminated timber, which is the process step crucial for the quality of the end product, was very limited. The time in the press for setting/pressing, however, was comparatively long, with the respective low productivity. The new Jowapur® 686.70 is very different and introduces a new generation of adhesives that combine a high quality of the end product with substantially increased efficiency for the machine.