Societa Cavi Pirelli S.p.a.

Pirelli Cable Corporation

Prysmian Cavi E Sistemi Energia S.r.l.

Carlo Marin

Fabrizio Marciano-Agostinelli

Sergio Belli

Alberto Bareggi

Gianmario Lanfranconi

Fabrizio Donazzi

Marco Barbaro-Forleo

Giovanni Pozzati

Cesare Bisleri

Andrea Borroni

Cesare Seveso

Paul L Cinquemani

Paul K dePratter

Frank L Kuchta

A cable for use in a predetermined voltage class, has a conductor; an insulating layer surrounding the conductor, the insulating layer having a thickness selected to provide a predetermined electrical stress when the cable is operated at a nominal voltage in said predetermined voltage class; and a protective element around the conductor having a thickness and mechanical properties selected to provide a predetermined impact resistance capability, the protective element having at least one expanded polymeric layer. The insulating layer thickness and the protective element thickness are selected in combination to minimize the overall cable weight while preventing a detectable insulating layer damage upon impact of 50 J energy. A method for designing a cable is also disclosed.

Impact resistant compact cable

An electrical power cable with a stranded conductor, a semi-conductive stress control layer around the conductor, a layer of insulation around the stress control layer, a semi-conductive insulation shield layer around the layer of insulation, an imperforate metal strip with overlapping edge portions around the shield layer and a polymeric jacket around the metal strip. The strip is free to move with respect to the jacket and the shield layer with expansion and contraction of the cable elements with temperature changes, and the overlapping edge portions of the strip are bonded together by an adhesive which permits the edge portions to move relative to each other with such temperature changes without creating fluid passageways between the edge portions. A cushioning layer can be between the shield layer and the strip and preferably, the cable is water sealed.

Multi-layer power cable with metal sheath free to move relative to

Method and apparatus for applying a layer of insulation around an electrical cable core in which the contaminant size is not greater than about 200 microns. Unplasticized insulation material, such as polyethylene, is supplied to an extruder which forces the material through a filter which prevents the passage of contaminants having a size greater than about 200 microns and in which there is a pressure drop. The filtered material is delivered to a pump which increases the pressure thereon and forces it through a static mixer at the output of which the filtered material is delivered to the cross-head of extrusion apparatus which applies the filtered material to the cable core as it is advanced longitudinally. If the insulating material is to be cross-linked by a cross-linking agent, the agent is injected into the filtered material between the pump and the mixer.

Extrusion process and apparatus for low contaminant cable insulation

A high voltage electrical power cable with a stranded central conductor encircled by insulation, a metal tape, metal strips or metal wires following helical paths outwardly of the insulation and a water swellable material at least between the adjacent edges of the tape, strips or wires. Preferably, the water swellable material is included with a polymeric material which is flowable at a temperature at least as low as 100.degree. C., the polymeric material has a 100 gram needle penetration value in the range from 50-100 tenths of a millimeter at 25.degree. C. and the water swellable material has a particle size not greater than 200 microns.

Power cable with water swellable agents and elongated metal elements

An electrical cable with a core comprising an electrical conductor surrounded by insulation and with both a screen of wires in open helix configuration on the core and at least one other wire extending longitudinally of the core and electrically contacting the wires of the screen. An insulating sheath surrounds the screen and may itself embed the wires or it may surround a layer of extruded material which at least partially embeds the wires. The material of the layer may be insulating or semi-conductive. Also, a process for manufacturing such cable.

Electrical cable with open helix screen wires electrically contacting a

A filler compound for the spaces between the wires of a stranded conductor surrounded by and contacting a semiconductive layer which is surrounded by a layer of extrudced insulation, a method for filling such spaces with the compounds and an electric cable including such compound. The compound has a polymeric base, a Mooney viscosity at 100.degree. C. between 10 and 60 and a Shore A hardness between 10 and 90. Preferably, the compound includes hygroexpansible, water insoluble organic powder having particle sizes less than 200 microns and specified other characteristics.

Electric cable with stranded conductor filled with water blocking

A granulator for forming granules of cross-linkable plastic compounds in which a screw extruder extrudes the compound into the smaller diameter end of a funnel-shaped, annular conduit, the other end of the conduit facing a die with circular arrays of through-holes. The compound which passes through the through-holes is cut into granules by rotating blades having air nozzles which remove particles of the compound from the blades. The granules are received in a chamber from which they are removed pneumatically. Where the annular conduit meets the die, there are channels within and outside of the arrays of through-holes which lead to the outside of the granulator and which provide conduits for removal of compound which does not directly impinge on the entrances of the through-holes which are specially shaped to avoid accumulation of the compound between the through-holes.

Growing community of inventors

Vigevano, Italy

Carlo Marin