METHOD AND RELATED APPARATUS FOR PRESSURELESS OR ALMOST PRESSURELESS INTRODUCTION OF FOAM INTO A PRESSURISED MATERIAL FLOW

摘要

The object of the present invention is to provide a method with related apparatus with the aid whereof foam can be supplied in a pressureless or almost pressureless manner to a pressurised material flow in such a manner that the predefined mixing ratio of the two material components remains constant or almost constant. The admixing device according to the present invention consists of a pipe carrying the material flow in which a cross-sectional constriction is configured in such a manner that the flow velocity of the material flow is increased at this point with the consequence that a negative pressure zone is formed in the material flow on the downstream side of the cross-sectional constriction, into which the foam can be introduced into the material flow in a pressureless manner or at low excess pressure.