Process and apparatus for the production of corrosion protection for cables made of parallel wire strands

Claim 2

A process for producing a parallel wire tension member protected from corrosion and for use in cable stayed bridges comprising: (a) supplying a prefabricated parallel wire bundle from a supply source; (b) conveying the wire bundle through a spreader and reforming die means to spread the wire strands of the bundle apart without disassembling the bundle and reforming the strands in a parallel wire bundle by collecting them together at the reforming die; (c) injecting from within the spread strands a tacky synthetic resinous material with an anti-corrosion ingredient to coat all the strands while they are converging towards the reforming die, the resinous material being contained by an injection housing during injection and being sufficient in quantity to completely fill the interstices between the strands after the reforming strip; (d) applying a close-fitting sheet metal casing to the composite reformed wire bundle and resinous material while the latter is still in tacky condition to thereby enclose same and to bond the casing to at least a portion of the length of the wire bundle, the quantity of the resinous material being sufficient to substantially fill the area between the wires strands and the casing, and the metal casing being longitudinally rigid to the extent that the encased wire bundle cannot be bent beyond a predetermined large radius of curvature without deforming the metal casing; (e) curing and hardening the resinous material while the encased wire bundle is maintained in substantially straight condition, i.e., with a radius of curvature not smaller than said predetermined radius of curvature.

Claim 3

The process according to claim 1, the step of supplying the fabricated wire bundle including supplying the bundle from a single supply reel.

Claim 4

The process according to claim 1, said sheet metal casing comprising a single, longitudinally extending corrosion resistant sheet, and the step of applying the sheet to the bundle comprising circumferentially wrapping the metal sheet about the wire bundle with a protective open space beneath the abutting edges only, welding the abutting edges together longitudinally along the bundle, and finally filling the open space with synthetic resinous material, whereby the wire bundle is hermetically sealed by the metal casing.

Claim 5

The process according to claim 1, wherein the resinous material is selected from the group consisting of a polyurethane, an epoxy resin and a polyester.

Claim 6

The process according to claim 3, including wrapping the sheet metal about the wire bundle while providing a second, longitudinally extending open space between the composite wire bundle and resinous material, and the metal casing, the second open space comprising an expansion space for excess resinous material, and filling any voids in the second area with resinous corrosion protection material.

Claim 7

The process according to claim 5, said second open space being protected by locally deforming the metal casing in the space of the second open area.

Claim 8

The process according to claim 3, including applying temporary, annular, rigid, radially constricting means at longitudinally spaced intervals along the wire bundle externally of the metal casing.

Claim 9

The process according to claim 5, said prefabricated wire bundle including at least one terminal means for securing the wire strands together and anchoring the wire bundle, the metal casing terminating before the terminal means, including the step of applying to the metal casing a longitudinally adjustable enclosing means adjacent the terminal means for enclosing and sealing the wire bundle between the end of the metal casing and the terminal means, and thereafter filling any open portions of said first and second open areas and the interior of said enclosing means with an anti-corrosive synthetic resin material.

Claim 10

The process according to claim 1, including applying to the metal casing an outer corrosion protective layer comprising a glass-fiber reinforced unsaturated polyester containing a minor amount of an acrylic polymer admixed therewith.

Claim 11

The process according to claim 1, said synthetic resinous material comprising a polyurethane, the process further including the steps of wrapping said reformed wire bundle with a plurality of layers of butyl rubber coated foil and vulcanizing said layers together by heat.

Claim 12

The process according to claim 1, including tightly winding wire under tension around the reformed and resin filled wire bundle with the quantity of resinous material being sufficient to seal the wound wire layer before the sheet metal casing is applied.

Claim 13

Apparatus for producing a tension member comprising a bundle of parallel wire strands protected from corrosion and for use in cable stayed bridges comprising: (a) means for spreading the wire strands apart without disassembly of the bundle; (b) means, spaced from said spreading means, for reforming the wire strands into the bundle; (c) an injection housing positioned between said spreading and reforming means and defining a chamber including a longitudinal passage therethrough; (d) means for conveying the wire bundle through said longitudinal passage and through said spreading and reforming means to spread the wire strands of the bundle apart without disassembling the bundle and reforming the strands in a parallel wire bundle by collecting them together at the reforming means; (e) means including an injection nozzle in said chamber for injecting from within the spread strands a tacky synthetic resinous material with an anti-corrosion ingredient to coat all the strands while they are converging towards the reforming means, the resinous material being contained by the injection housing during injection and being sufficient in quantity to completely fill the interstices between the strands after conveying through the reforming means; and (f) means, located subsequent to said reforming means, for applying a close-fitting sheet metal casing to the composite reformed wire bundle and resinous material while the latter is still in tacky condition to thereby enclose same and to bond the casing to the wire bundle, wherein the quantity of the resinous material is sufficient to substantially fill the area between the wire strands and the casing, and the metal casing being longitudinally rigid to the extent that the encased wire bundle cannot be bent beyond a predetermined large radius or curvature without deforming the metal casing.

Claim 14

Apparatus for producing a tension member comprising a bundle of parallel wire strands protected from corrosion and for use in cable stayed bridges comprising: (a) means for spreading the wire strands apart without disassembly of the bundle; (b) means, spaced from said spreading means, for reforming the wire strands into the bundle; (c) an injection housing positioned between said spreading and reforming means and defining a chamber including a longitudinal passage therethrough; (d) means for conveying the wire bundle through said longitudinal passage and through said spreading and reforming means to spread the wire strands of the bundle apart without disassembling the bundle and reforming the strands in a parallel wire bundle by collecting them together at the reforming means; (e) means including an injection nozzle in said chamber for injecting from within the spread strands a tacky synthetic resinous material with an anti-corrosion ingredient to coat all the strands while they are converging towards the reforming means, the resinous material being contained by the injection housing during injection and being sufficient in quantity to completely fill the interstices between the strands after conveying through the reforming means; and (f) means, located subsequent to said reforming means, for applying a close-fitting sheet metal casing to the composite reformed wire bundle and resinous material while the latter is still in tacky condition to thereby enclose same and to bond the casing to the wire bundle, wherein the quantity of the resinous material is sufficient to substantially fill the area between the wire strands and the casing, and the metal casing being longitudinally rigid to the extent that the encased wire bundle cannot be bent beyond a predetermined large radius or curvature without deforming the metal casing.

Claim 15

Apparatus as recited in claim 12, wherein said casing applying means comprises means for continuously supplying sheet metal strip stock and tightly wrapping the sheet metal strip circumferentially about the reformed bundle while it is conveyed so that a single longitudinal seam is presented along the bundle, and welding means for continuously welding the seam closed after the metal has been wrapped.

Claim 16

Apparatus as recited in claim 13, including roller means for supporting the distal end of the reformed and encased wire bundle and intermediate areas of said bundle while the bundle is being conveyed.

Claim 17

A process for producing a parallel wire tension member protected from corrosion and for use in cable stayed bridges comprising the steps of: (a) supplying a prefabricated parallel wire bundle from a supply source; (b) conveying the wire bundle through a spreader and reforming die means to spread the wire strands of the bundle apart without disassembling the bundle and reforming the strands in a parallel wire bundle by collecting them together at the reforming die; (c) injecting from within the spread strands a tacky synthetic resinous material with an anti-corrosion ingredient to coat all the strands while they are converging towards the reforming die, the resinous material being contained by an injection housing during injection and being sufficient in quantity to completely fill the interstices between the strands after the reforming strip; (d) tightly winding wire under tension around the reformed and resin filled wire bundle, with the quantity of resinous material being sufficient to also seal the wound wire layer; and (e) applying a close-fitting sheet metal casing in the form of continuously helically wound sheet metal strips under tension about the composite reformed, wire-wound, resin-filled wire bundle while the resinous material is still in tacky condition to thereby enclose same and to bond the casing to the wire bundle, the quantity of the resinous material being sufficient to substantially fill the area between the wire strands and the casing, and the metal casing being longitudinally rigid to the extent that the encased wire bundle cannot be bent beyond a predetermined large radius of curvature without deforming the metal casing.

Claim 18

A process for producing a parallel wire tension member protected from corrosion and for use in cable stayed bridges comprising the steps of: (a) supplying a prefabricated parallel wire bundle from a supply source; (b) conveying the wire bundle through a spreader and reforming die means to spread the wire strands of the bundle apart without disassembling the bundle and reforming the strands in a parallel wire bundle by collecting them together at the reforming die; (c) injecting from within the spread strands a tacky synthetic resinous material with an anti-corrosion ingredient to coat all the strands while they are converging towards the reforming die, the resinous material being contained by an injection housing during injection and being sufficient in quantity to completely fill the interstices between the strands after the reforming strip; (d) tightly winding wire under tension around the reformed and resin filled wire bundle, with the quantity of resinous material being sufficient to also seal the wound wire layer; and (e) applying a close-fitting sheet metal casing in the form of continuously helically wound sheet metal strips under tension about the composite reformed, wire-wound, resin-filled wire bundle while the resinous material is still in tacky condition to thereby enclose same and to bond the casing to the wire bundle, the quantity of the resinous material being sufficient to substantially fill the area between the wire strands and the casing, and the metal casing being longitudinally rigid to the extent that the encased wire bundle cannot be bent beyond a predetermined large radius of curvature without deforming the metal casing.

Claim 19

The process according to claim 1, wherein said sheet metal casing comprises a highly-alloyed, stabilized, high-quality steel.