Dry-spray products for protecting centrifugal casting molds of cast iron pipes in association with a wet-spray product

摘要

A powder, for protecting moulds for the centrifugal casting of iron pipes is produced by: (A) creation of a wet-spray layer on the hot inner surface of the mould with an aqueous solution of silica and bentonite; (B) dry spraying this layer with a powder product containing a metal inoculant alloy or alloys, possibly some powdered anti-pitting agents and possibly an inert mineral charge; (C) centrifugally casting the iron pipe; (D) removing the pipe from the mould. The powder product also incorporates an additive to assure the adhesion of the wet-spray layer on the iron pipe during demoulding.