The pouring and doctor streak of Urethane adhesives on conveyor-systems needs a head-flush whenever the line should be stopped. The adhesive consumption is enormeous. The shift-thicknesses are more than 1mm and adhesive-toppings are disturbing the systems often.
The spraying of adhesives gives a thinner and more uniform thickness compared to the poured application. In connection with our selfdevelopped oscillating systems with a speed up to 2m/s ISOTHERM machines are in use since 1993 to spray PU-rigid foam as glueing systems for insulation panels.

An upper and a lower profiled metal sheet coming from coils are brought together with mineral wool-stripes in a conveyor system.
The PU adhesive is sprayed directly between mineral wool and metal-sheets, shortly before the whole panel goes through a heated press.
The output range here is about 12 g/s. A similar equipment is in use to agglutinate accoustic boards.