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.