METHOD AND DEVICE FOR EXTRUSION OF GUARD RAILS FROM THERMOPLASTICS Russian patent published in 2013 - IPC B29C47/02 

FIELD: process engineering.

SUBSTANCE: invention relates to continuous extrusion of constant cross-section guard rails for moving stairways or other conveyors from thermoplastics. Extruded article should have invariable cross-section and contain first thermoplastic, stretch limiter and fabric on its one side. Note here that proposed method comprises feeding stretch limiter to extrusion head and feeding first melted thermoplastic to said head. Note also that first thermoplastic temperature is lower that stretch limiter melting point. Then, first thermoplastic is combined with stretch limiter for the latter to be located there inside. Then, constant-width long strip of material is fed. Note also that first thermoplastic extrusion temperature is lower that stretch limiter melting point. Then, fabric is fed to first thermoplastic bottom side for bonding it therewith to support first thermoplastic to make thereof the stretch limiter and fabric of composite extrudate. The latter is then cooled down and cured.

EFFECT: higher strength of guard rail sides.