Method and High-Pressure Mixing Device for the Co-Injection of Polymeric Components

摘要

A method and high-pressure mixing device for co-injection of polymeric reactive components, in particular for polyurethane and epoxy mixtures. The polymeric components are supplied in a common pressure chamber where they flow at a same pressure and in an unmixed state into a forwardly converging fore portion of the pressure chamber, and through a settable co-injection orifice to be co-injected, in the unmixed state, into a mixing chamber transversely oriented to the pressure chamber. The settable co-injection orifice consists in an elongated restriction; a first cleaning member and a second cleaning member are sequentially reciprocable in the pressure chamber to eject the remaining unmixed polymeric components, respectively in the mixing chamber to eject the remaining mixture, and stop means are provided to set an open section of the elongated restriction.

主权项

1. A method for mixing a first and at least a second polymeric reactive component by a self-cleaning high-pressure mixing device comprising a pressure chamber configured with a forwardly converging fore portion in fluid communication with a mixing chamber through a settable co-injection orifice;
comprising the steps of: feeding the first and at least the second reactive components into the pressure chamber maintaining the reactive components inside the pressure chamber at a same pressure and in an unmixed state; flowing the reactive components at said pressure and in the unmixed state, into the pressure chamber and into the forwardly converging fore portion to increase the flow velocity; configuring the co-injection orifice in the form of an elongated restriction longitudinally extending to the mixing chamber, transversely oriented and intersecting the forwardly converging fore portion of the pressure chamber; adjusting the pressure of the unmixed reactive components in the pressure chamber, setting an open section of the elongated restriction of the co-injection orifice by adjusting, in respect to the same co-injection orifice, the fore end position of the second cleaning member at the retracted condition thereof; and co-injecting the unmixed reactive components into the mixing chamber, causing a pressure drop and mixing the reactive components, while they are flowing through the set open section of the co-injection orifice and into the mixing chamber of the mixing device; and ejecting the remaining unmixed reactive components from the pressure chamber and from the forwardly converging fore portion, and ejecting a remaining mixture from the mixing chamber, by first and respectively second cleaning members having a fore end, the cleaning members being reciprocable between a retracted and an advanced condition in the pressure, respectively in the mixing chamber of the mixing device.