Abstract: The present invention relates to a spacer for high pressure mixing head comprising a control cylinder flange, a head body flange, and a plurality of uprights adapted to interconnect the control cylinder flange and the head body flange. At least one of the plurality of uprights comprises at least one deformation detection sensor applied at at least one available deformation surface thereof and adapted to detect longitudinal deformations and/or transversal deformations of the at least one of the plurality of uprights. The present invention also relates to a related mixing and dosing head and to a related apparatus.

Abstract: The invention relates to a high-pressure mixing, dosing and recirculation head for injection or casting reaction molding, said high-pressure mixing, dosing and recirculation head comprising a head body, a mixing chamber, obtained in the head body wherein a valve element or mixing valve slides and in fluid communication with a supply duct, and a self-cleaning element comprising a scraping portion, said self-cleaning element being structured to slide in said supply duct, as well as comprising an apparatus for controlling and commanding mixing, supply and recirculation comprising a plurality of sensors and transducers mounted on board of the head body and of the components parts of the head connected thereto to detect and transform representative physical quantities of at least one operational status of said high-pressure mixing, dosing and recirculation head into electrical signals and an electronic control and storing system adapted to synchronously control and scan said sensors and transducers and adapted to

Abstract: A method and apparatus for feeding a polyurethane mixture suitable to form a thermally insulating layer inside hollow bodies, such as hollow walls of a refrigerator cabinet, freezer, display counter or insulating panel. A polyurethane mixture resulting from chemically reactive components, supplied by a high-pressure mixing device, is injected into a cavity of a hollow body extending in a horizontal plain. The mixture is injected at a first flow-rate and a first injection speed, to be poured into a first deposition zone farthest from the injection point. Subsequently, the flow-rate and the injection speed of the polyurethane mixture are gradually reduced in a controlled manner, to be poured in successive deposition zones towards the injection point of the polyurethane mixture, along a distribution strip, allowing the injected mixture to spread out throughout the cavity of the hollow body along isometric expansion lines.

Abstract: A high-pressure mixing apparatus for producing and discharging a composite material resulting from a reactive mixture of at least a first and a second chemical components and from a filler material. The apparatus includes a main body, provided with a discharge duct for the composite material, at least one high-pressure mixing chamber for the chemical components and a first cleaning member axially displaceable between a forward and a rearward position within the discharge duct. The apparatus also comprises a second cleaning member with a control device selectively actuable to sequentially move the first and the second cleaning member between the rearward position, in which the first cleaning member opens the discharge duct, and the forward position in which the facing annular surfaces of the discharge duct and the second cleaning member are mutually abutting to eject the residual reactive mixture and close the exit port of the mixing chamber.

Abstract: A method and an apparatus for high-pressure mixing of reactive chemical components. The chemical components are fed into a mixing chamber, by respective injectors at least one of which comprises a nozzle and a plug member for controlling the pressure drop; the nozzle and/or the plug member are shaped to form a lobed outlet orifice having an adjustable outlet cross section and a plurality of radially extending lobed formations, to create a vortical or swirling and highly turbulent state in the fluid jet. The surfaces in contact with the fluid of the nozzle and/or of the plug member can either be smooth or have sharp edges which contribute to increase the turbulence and swirling state of the fluid jet; a highly effective mixing degree is thereby achieved in the manufacture of polyurethane resins, bi-component resins and molded articles.

Abstract: The high-pressure mixing apparatus, for reactive chemical components, comprises a device for self-lubricating and scraping the outlet duct of the chemical mixture, and flushing out the scraped residues. The self-lubricating and scraping device comprises a delivery chamber for the lubricant material axially aligned and in fluid communication with the outlet duct; the lubricant delivery chamber is connected to a storage tank by a feeding and re-circulation circuit. The lubricant is sucked into the outlet duct and subsequently returned into the delivery chamber by a cleaning member in the form of a pumping piston sliding into the outlet duct, the pumping piston being provided with scraping rings for removing the reacted mixture adhered to the inner surface of the outlet duct.

Abstract: A method and device (10) for mixing polyurethane-forming liquid chemical components for the production of polyurethane foams, in which positive use is made of the turbulency and swirling action caused by the injection of pressurized jets of chemical components, in order to provide a methodology tending to improve the mixing processes by impingement and by the turbulency induced by a pressure drop in conventional self-cleaning apparatuses.

Abstract: A process and an apparatus for the production of a polyurethane mixture is described. The apparatus comprises a high-pressure mixing device provided with a mixing chamber opening onto a side of a discharge duct. An elongated cleaning member is reciprocable inside the duct and is provided with a longitudinal channel for feeding a fluidized reinforcing material, for example reinforcing fibers or a reinforcing material in powder or granulate form, to be blended with the polyurethane mixture flowing into the discharge duct. The feeding channel for the reinforcing material terminates at the front end of the cleaning member, at a point where the flow of reinforcing material impinges the polyurethane mixture which emerges from the mixing chamber under high turbulence conditions. Blowing nozzles are provided to generate air jets for repeatedly deviating the flow of blended polyurethane mixture and reinforcing material flowing out from the discharge duct.

Abstract: A high-pressure self-cleaning mixing apparatus adapted to mix at least first and second reactive polyurethane-forming components and feed the mixed components to a mold is disclosed. The apparatus includes at least a mixing chamber, first and second feed passages, first and second recycle passages, and a cleaning member having at least first and second longitudinally-extending recycle grooves spaced from each other. The cleaning member is movable between an open position in which the first feed passage radially feeds the first polyurethane-forming component to the mixing chamber and a closed position in which the first longitudinally-extending recycle groove communicates the first feed passage with the first recycle passage to recycle the first polyurethane-forming component instead of feeding the first polyurethane-forming component to the mixing chamber.

Abstract: The invention refers to a high-pressure mixing device, for at least two chemical components to be mixed, in particular of the type having a movable mixing chamber, in which the mixing chamber communicates with an outlet duct for discharging the mixture therefrom through a lateral passage and in which the component inlet apertures open directly into the mixing chamber but are oriented so as to face away from the lateral passage in a direction which is opposite to the flow of the mixture in the outlet duct.

Abstract: A high-pressure mixing head for at least two fluid components to be mixed together.The mixing head comprises a movable mixing chamber, defined by a cylindrical hole whose longitudinal axis is parallel to the axis of an outlet duct; the mixing chamber is provided in a slider movable in a guide channel at right angles to and crossing the outlet duct for the mixture. The slider is movable from a first operative position in which the chamber is disposed on one side of the outlet duct, in correspondence with the nozzles for injecting the components to be mixed, and in which the outlet aperture of the mixing chamber communicates with the outlet duct, to a second position in which the injectors communicate with component recycling ducts, and in which the mixing chamber is axially aligned with the outlet duct and with a sliding cleaning member.

Abstract: A plant for molding articles in polyurethane material; the plant comprises a plurality of motorized mold supporting carriages independently movable along a suspended monorail running along a production line. Each carriage comprises a mold supporting press for opening and closing a mold provided with independent pneumatic control means supported by the same carriage; the control means are connectable to a source of fluid under pressure in pre-established working positions along the production line; each carriage also comprises a drive unit connected to electrical power supply bus bar along the monorail and a peripheral control unit operatively connected to a central logic unit by dialogue conductors provided on the monorail.

Abstract: A mixing method and apparatus for preparing multi-component plastic materials, especially polyurethanes, which are mixed before being fed into a mold. According to the invention, a first and at least a second main component are mixed by feeding them into a limited area of a mixing chamber through lateral inlet apertures symmetrically arranged with respect to a plane comprising the longitudinal axis of the chamber and in which a third or secondary component to be mixed is fed through a channel, opening in the chamber upstream of said inlet apertures and orientated so as to direct the flow of the third or secondary component towards said mixing area in the direction of flow of the mixture. A control member is moved toward an advanced position so that it closes the inlet apertures to interrupt feeding of the first and second main components and a coloring agent through respective inlet apertures after a mixing operation.