Abstract: An apparatus and method for optimally mixing and injecting a two part urethane foam which utilizes a unique mixing head having needle type valves which are specially sealed and positioned, able to provide precisely controlled amounts of constituent mixing compounds, and are further able to resist clogging. The apparatus further includes an electric-pneumatic actuation system, an unmixed compound recirculation system, and a cleaning solvent injection system which are functional while the apparatus is in use. The apparatus and method precisely controls the temperature, pressure, and delivery rates for optimum urethane mixture, viscosity, delivery, reaction time, and reliability.

Abstract: An apparatus and method for mixing and injecting or applying a viscous material which is especially useful for mixing and applying a two part epoxy. The apparatus in its preferred form utilizes two uniformly heated holding tanks with auger feeds which each feed two synchronized variable ratio pumps having spring biased check valves which ensure positive closure of each valve. The apparatus further comprises a unique dispensing and mixing head which is fed from the synchronized pumps and serves to uniformly mix the viscous materials and dispense the aforesaid as a blend.