Shaped saw wire with controlled curvature at bends
AssigneeBekaert Binjiang Steel Cord Co., Ltd.
InventorsAlain Simonart, Wenxian Huang
Life of this patent
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Abstract
A saw wire to cut hard and brittle materials is disclosed that comprises a steel wire that is provided with bends with segments in between. The average degree of bending of the bends is between 0.5% and 5%. Such a saw wire has a higher breaking load compared to saw wires having a conventional, higher average degree of bending. A method to measure the curvature is described as well as a process to make the inventive saw wire. The invention is applicable to any shaped saw wire for example a single crimped saw wire, a saw wire with at least two crimps in different planes, a saw wire with crimps rotating in a plane.
Claims10
A method to produce a saw wire comprising the steps of:
- providing a steel wire with a diameter (d) and a breaking load (Fm);
- leading said steel wire over one or more bending devices,
- said bending devices having teeth with a teeth radius (Rt),
- said steel wire being held under a tension (T) immediately after the one or more bending devices,
- thereby inducing bends in said steel wire at the teeth and segments in said steel wire between the teeth thereby forming a saw wire,
- wherein each bending device has an intermeshing toothed wheel pair through which the steel wire is led thereby forming crimps in said steel wire,
- wherein the intermeshing toothed wheel pairs have indentations that are between 1 to 10 times the diameter (d) of said steel wire, and
- wherein the teeth radius (Rt) is larger than or equal to 4 times the diameter (d), while said tension (T) is held between 3% and 30% of the breaking load (Fm), for controlling the average product of a top curvature (ki) at each of said bends with half of said diameter (d) over at least 50 bends to within 0.5 and 5 percent.
A method to produce a saw wire comprising the steps of:
- providing a steel wire with a diameter (d) and a breaking load (Fm),
- leading said steel wire over one or more bending devices,
- wherein each bending device has an intermeshing toothed wheel pair through which the steel wire is led thereby forming crimps in said steel wire,
- wherein the intermeshing toothed wheel pairs have indentations that are between 1 to 10 times the diameter (d) of said steel wire, and
- wherein the toothed wheel pairs of said one or more bending devices have teeth with a teeth radius (Rt),
- thereby inducing bends in said steel wire at the teeth and segments in said steel wire between the teeth thereby forming a saw wire,
- measuring a tension (T) of said saw wire immediately after the one or more bending devices,
- holding said saw wire under the tension (T),
- wherein
- the teeth radius (Rt) is larger than or equal to 4 times the diameter (d), while said tension (T) is held between 3% and 30% of the breaking load (Fm), for controlling the average product of a top curvature (ki) at each of said bends with half of said diameter (d) over at least 50 bends to within 0.5 and 5 percent.
Dependencies are inferred from the claim text.