ES352803A1 - Pressure hoses - Google Patents

Abstract

A process for the manufacture of pressure hoses comprising an inner hose 1, of natural or synthetic rubber, and reinforcing elements 3 of textile or metal around the inner hose, is characterized in that the inner hose 1 has a layer of P.V.C. in powder form applied to it as it is extruded, and the reinforcing elements are embedded in P.V.C. and braided, or wound, outside the P.V.C. layer. The assembly thus provided being subjected to heat treatment to unite the P.V.C. and the reinforcement elements with the inner hose. As shown, an extruded hose 1 of natural or synthetic rubber is covered, during extrusion, with a thin layer 2 of P.V.C. in powder form and then with a P.V.C. paste, which jellifies at the normal vulcanizing temperature, before a protective layer of braided P.V.C. tapes 3 is applied, the tapes 3 having embedded therein either textile or metallic reinforcements. In a modification, Fig. 2, not shown, two braided textile layers (4, 4) covered with P.V.C., are interposed between the layer (2) of P.V.C. powder and the outer braided cover of P.V.C. tapes (5), the assembly then being vulcanized at a temperature of approximately 145 C. In a further modification, Fig. 3, not shown, steel wire braidings (6, 7) are separated by a layer (8) of paste, a second layer (8) of which is sandwiched between the braiding 7 and an outer protective cover 9 of braided P.V.C. tapes provided with longitudinal reinforcements.