Portable Helix Mixer for Urethane Foam

Abstract

A urethane foam mixer newly developed by Du Pont is light and compact, has no moving parts, yet blends urethane foam feed streams thoroughly as the mixture flows through a spiral chamber. The "helix" mixer has been used to process rigid and flexible urethane foams by both conventional and froth meth ods. It is easily adapted to existing foam me tering systems for factory or field application. It produces foams with cell structure and physical properties equivalent to those ob tained with heavy duty, agitator-type mixers. The helix mixer has been adapted and used for the trigger controlled on-off dis charge of mixed foam materials. The varia bles which affect helix mixer output and mix ing efficiency have been investigated, which will permit mixer scale up to outputs of sev eral hundred pounds per minute.