CASTING Russian patent published in 2003 - IPC

FIELD: method for casting of thin-walled tube-shaped container. SUBSTANCE: the method of manufacture of flexible thin-walled articles consists in the fact that polymeric mixture is fused and injected in a mould, then polymer is selected that is resistant to cracking under the action of the stress of the environment exceeding 10 hours, determined by the test results in compliance with the following procedure: (a) casting of a great number of strips of polymeric mixture is accomplished, including any treatment after casting designed for production of a finished article, having cross-section dimensions making up 0.65 mm in thickness and 10 mm in width in the conditions of duration of long flow with a large shift similar to those that are designed for use in manufacture of a flexible thin-walled article; (b) bending of the strips to yourself is conducted and broached by brackets at a distance of 3 mm from the bend; (c) the bent strips are immersed in a solution of an agent causing cracking under the action of stress, for example, in a 10-% solution of matter Terik No.9 and sustained at a temperature of 50C; (d) the strips are examined for the signs of cracking, considering any signs of cracking as a defect; (e) the time to failure is determined as the moment when 50% of the strips manifest the signs of cracking, then polymeric mixture is injected in a mould having a cavity, which produces a thin-walled article, having a thin section, 1 mm thick or less, this thin section is in essence continuous for the space of more than 50 mm in the direction of flow of fused polymeric mixture in the mould. Then the thin-walled article molded of polymeric mixture is extracted from the mould. The thin-walled tube is manufactured by this method. EFFECT: provided casting of articles with long thin sections for their industrial or domestic use, it is guaranteed that polymer will flow well in a long, narrow and curvilinear trajectory and have good mechanical properties. 17 cl, 18 dwg, 14 ex, 3 tbl