A method is disclosed for preparing and dispensing a mixture obtained by mixing at least one first chemically reactive component and at least one second chemically reactive component containing a dispersed solid material by a high pressure mixing device comprising a mixing chamber for mixing the components, in which a valve member is slidable, in particular a slide-valve, provided with longitudinal slots for recirculating the components to respective storage tanks. The method provides removing from at least one tank, a dosed quantity of the at least second chemically reactive second component to with filler material is added; recirculating the second component through the slots of the slide-valve for a period of time that is comparatively very reduced with respect to a recirculating step of the at least first component through the slide-valve. An apparatus for preparing and dispensing the mixture is also disclosed.

A cleaning piston for a mixing head of a reaction moulding machine includes a main part which has a cylindrical casing region, and a clearing part. The material and geometry of the clearing part are designed to remove residual material adhering to a channel of the mixing head. The clearing part is at least partly made of non-polar material.

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 that longitudinally extends on a side wall of the mixing chamber orthogonally oriented to an intersecting the forwardly converging fore portion of the pressure chamber; 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 elements are provided to set an open section of the elongated restriction, by adjustably stopping the fore end of the cleaning member for the mixing chamber, in respect to the same elongated restriction of the co-injection orifice.

A system for generating and dispensing plural component materials includes a controller operatively connected to dispense valves and return valves. The return valves are in respective open states to allow constituent materials to circulate back to a source and are in respective closed states to block circulation. The dispense valves are in respective open states to allow mixing of the constituent materials to form the plural component material and in respective closed states to prevent generation and dispense. The controller implements a delay between closing the return valves and opening the dispense valves to build pressure in the system prior to generating and dispensing the plural component material.

A melting device includes a container capable of melting a material supplied in a free-flowing state and storing the material in a liquid state. The container includes a first storage section for storing the material in the free-flowing state, a second storage section for storing the material in the liquid state, and a dividing section provided between the first storage section and the second storage section and configured to hold back the material, when the material is in a non-molten or free-flowing state and to allow passage of the material from the first storage section into the second storage section, when the material is in a molten or liquid state.

The application relates to a mixing head including a head part and a mixing chamber device which is arranged in the head part. The mixing chamber device has a mixing chamber, which includes at least two inlets for introducing a starting material into the mixing chamber, and an outlet, via which the starting material mixture can be discharged out of the mixing chamber. A control piston is movably arranged in the mixing chamber. The mixing chamber device is releasably arranged in the head part in order to be exchangeable, wherein a transition fit and/or a clearance fit is formed between the head part and the mixing chamber device. The application additionally relates to a production method.

A high pressure mixing head for continuously producing polymeric foam comprises a body including a mixing chamber and injectors for injecting two polymeric liquids. The mixing head also includes a delivery duct which is disposed transversely to the mixing chamber, wherein a rod is slidably received in an internal passageway of the delivery duct. An alternate delivery duct is also included. The delivery duct and the alternate delivery duct are in flow communication with the mixing chamber via a switchable flow connection, and a control unit is configured to control the switchable flow connection and the positions of the rods in the delivery duct and the alternate delivery duct such that flow from the output opening of the mixing chamber can be selectively directed either to the delivery duct or to the alternate delivery duct.