Method for preventing encrustation of a cold-curing foundry-sand mixture on those parts of a foundry-sand mixer which come into contact with it

摘要

In this method, those parts of the mixer which come into contact with the mixture are sprayed, before the mixing operation starts, with an agent which prevents or delays the hardening of the mixture on these parts. Spraying is expediently also carried out after the conclusion of the mixing operation. A liquid agent with a lubricating effect can be used to delay or prevent the curing of the mixture as long as the mixture is in contact with the agent. The method is particularly suitable for the production of mixtures composed of sand, binder resin and acid as a catalyst for foundry moulds or cores. The mixer for carrying out the method is provided with a spraying device for spraying with the agent those parts of the mixer which come into contact with the mixture.