Sandwich Panels: Innovative Solutions Using Vacuum-Assisted Foam Injection

A new method for foaming sandwich insulation panels has been jointly developed by MISA (a large Italian panel manufacturer), Manni (the polymerization press manufacturer) and Cannon (the metering equipment manufacturer) with the co-operation of Dow-Italy (polyurethane chemicals supplier). Its functioning concept relies on the controlled application of vacuum inside the polymerization cavity of the press. A series of custom-designed inner-press adjustment mechanisms guarantee easy operation and consistency of results. High productivity has been achieved (more than 300 panels per shift) together with enhanced panel quality, savings on raw material and labor costs, and last but not least, a very clean workplace. The new process also presents opportunities for new polyurethane technology solutions. Blowing agent families with a wider range of boiling points can be used and, remarkably, polyisocyanurate foam can now be easily processed with this injection technique.