METHOD FOR PRODUCTION OF PLASTIC TANKS FOR PETROLEUM PRODUCTS Russian patent published in 2006 - IPC B29C49/04 B29D22/00 

FIELD: procedure of processing of polymeric materials.

SUBSTANCE: the polymeric materials are subjected to extrusion with an inflation. Plastication of the melt of polymeric material occurs in the extruder cylinder, extrusion of the melt in the form of a tubular blank occurs into the open cavity of a blow mould, joining of the half-moulds and inflation of the tubular blank by compressed gas. Then it is cooled down in the joined mould, the half-moulds are opened and the product is extracted. A mixture of aliphatic polyamide with polymers or copolymers of olefins or their mixtures functionalized by a graft of polar monomer is used as polymeric material, and the temperature of the blown-shaped pressure heads is taken to be equal to T_bpap≤T_ph≤0.85·T_fpop, where T_bpap - the temperature of the brittle point of aliphatic polyamide in a mixture; T_ph - the temperature of the mould pressure heads; T_fpop - the temperature of the fusing point of olefinic polymer of the most refractory component of their mixture. Inflation of the tubular blank is effected by dehumidified compressed gas. The temperature of the tubular blank is effected by dehumidified compressed gas. The temperature of the tubular blank at the moment of its inflation exceeds the crystallization point of aliphatic polyamide in a mixture.

EFFECT: enhanced strength of welds.

5 cl, 1 tbl, 21 ex