Constructions
The following are standard constructions available.
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Strand
Multiple wires that are laid together helically and symmetrically arranged with uniform pitch or lay.
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1x3
A simple construction of three single wires twisted together. This construction makes it a very flexible strand in small diameters. The strand becomes less flexible as diameters increase.
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1x7
Six wires are laid around one center wire. This strand is more flexible than a 1×3. This construction is commonly used for push-pull applications and for conductive needs with low flexibility.
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1x19
Twelve wires are laid around a 1×7 center. This construction is used for more flexible needs than a 1×7 in push-pull and conductive applications. A 1×19 strand is almost as high a breaking strength as a 1×7 strand with the same diameter.
Cable
Multiple strands that are laid together helically and symmetrically arranged in multiple layers with uniform pitch or lay.
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3x7
A combination of three 1×7 strands twisted together. This is a very flexible cable in small diameters.
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7x3
Six 1×3 strands cabled around a 1×3 center strand. The properties of this cable are the same as a 3×7 cable but is a much smoother cable on the outside. This cable is used for application requiring a smooth jacket but it is more costly than a 3×7 cable.
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7x7
Six 1×7 outside strands are cabled around a 1×7 strand center. This is the most standard cable construction. This produces a very flexible cable with good cycle life and excellent breaking strength.
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7x19
Six 1×19 strands are cabled around a 1×19 center strand. This is the most flexible standard construction for cable. This cable gives you a high cycle life but has a lower breaking strength and is more costly than a 7×7 cable.