For the production of PUR or PIR sandwich panel chemical components are used and properly mixed make the polyurethane foam. The mixing of these components occurs on the high pressure foaming and metering unit. This machine is composed by a series of tanks, pumps and measuring device that controlled by electronic equipment permit the formulation and metering of components on the distribution and pouring head. The polyurethane foam is distributed on the lower sheet with a distribution cross bar. This machine is equipped with one or two indipendent high pressure mixing and pouring heads that guarantee th continuous production without stop for maintenance.