Sika Schweiz Ag

Sika Technology Ag

Reto Koch

Reto Dohner

Kurt Berli

Roberto Cutri

The invention relates to a static mixer () having a cylindrical mixer channel formed by a mixer channel housing () and a multistage mixer blade element () which is disposed in said mixer channel and used for mixing layers of hardening accelerator paste in a stream of highly viscous PU. Discharge openings () are provided in the inlet area of the static mixer. Said discharge openings introduce a partial stream of hitherto unmixed highly viscous PU into. secondary channels () disposed parallel to the mixer channel. The secondary channels are connected to feeder openings () disposed in the wall of the mixer channel downstream of the mixer wing element () when viewed in the direction of flow. The unmixed PU is guided in the secondary channels () and enters the outer area of the stream coming from the mixer wing element via the feeder openings where the mixed layers of hardening accelerator paste are contained. The mixed stream is jacketed with a layer of unmixed PU to prevent layers of hardening accelerator paste from being discharged from an adhesive element applied with the aid of the mixer () and to prevent the occurrence of adhesive defects resulting therefrom.

Static mixer and method for mixing a main component with an additive

The present invention concerns a static mixing element ( ) having a mixing channel ( ) of substantially tubular shape which is undivided in axial direction and swirl vanes ( A, B) which are arranged beside each other and axially one after another in said mixing channel ( ) and which radially abut on the inner wall of said mixing channel ( ) and are, in this area, interconnected with said inner wall. Even in case of mixing very viscous components resp. mixing components at high flow rates, in which cases the forces applied by the flowing components to the swirl vanes ( A, B) are quite huge, the correct axial position of the swirl vanes, in particular in the entry area of the mixing element ( ), can be assured. Especially for long mixing elements ( ), this leads, under the before mentioned conditions, to a considerable improvement in mixing quality.

Static mixing element, single stage static mixing element segment, static mixer, mixing vanes element and method for mixing very viscous polyurethane with a curing accelerating agent

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Mägenwil, Switzerland

Reto Koch