METHOD AND DEVICE OF PRODUCING TUBES (VERSIONS) Russian patent published in 2010 - IPC B29C47/00 

FIELD: process engineering.

SUBSTANCE: invention relates to method and devices for producing tube inner coats for main lines. Positive effect is reached by proposed method of producing tube from thermosetting material. Proposed method comprises melting of initial material in extruder, forcing polymer thermosetting material into extrusion head, continuous extrusion of the tube and increasing tube diametre with the help of taper gage to contact cross section. Note here that extruded tube temperature is kept varying from extruder outlet melting temperature to that of softening in extruded tube diametre increase section, and, further on, to temperature of hardening of polymer thermosetting material at constant-section gage section. Note as well that extruder is located on mobile module inside the tube that doubles a constant-section gage. Tube extrusion is started simultaneously with displacement of module and increase in OD of extruded tube to ID of tube that acts as constant-section gage.

EFFECT: expanded performances and possibility to produce inner layer inside existing tube.

12 cl, 3 dwg