Strand: An element of rope usually consisting of an assembly of wires of appropriate shape and dimensions laid helically in the same direction in one or more layers around a center.

Round strand: A strand with a cross-section which is approximately the shape of a circle.

Triangular strand: A strand with a cross-section which is approximately the shape of a triangle.

Note: Triangular strands may have built-up centres (i.e. more than one wire forming a triangle.)

Compacted strand: A strand which has been subjected to a compacting process such as drawing, rolling or swaging whereby the metallic cross-sectional area of the wires remains unaltered and the shape of the wires and the dimensions of the strand are modified.

Note: Bridon’s brands of Dyform rope contain strands which have been compacted.

Single lay strand: Strand which contains only one layer of wires, e.g. 6-1.

Parallel lay strand: Strand which contains at least two layers of wires, all of which are laid in one operation (in the same direction), e.g. 9-9-1; 12-6F-6-1; 14-7+7-7-1. Each layer of wires lies in the interstices of the underlying layer such that they are parallel to one another, resulting in linear contact.

Note: This is also referred to as equal lay. The lay lengths of all the wire layers are equal.

Seale: Parallel ay strand construction with the same number of wires in each wire layer, each wire layer containing wires of the same size, e.g. 7-7-1; 8-8-1; 9-9-1.

Warrington: Parallel lay strand construction having an outer layer of wires containing alternately large and small wires, the number of wires in the outer layer being twice that in the underlying layer of wires, e.g. 6+6-6-1; 7+7-7-1.

Filler: Parallel lay strand construction having an outer layer of wires containing twice the number of wires than in the inner layer with filler wires laid in the interstices wires of the underlying layer of wires, e.g. 12-6F-6-1; 14-7F-7-1.

Combined parallel lay: Parallel lay strand construction having three or more layers of wires, e.g. 14-7+7-7-1; 16-8+8-8-1; 14-14-7F-7-1; 16-16-8F+8-1.

Note: The first two examples above are also referred to as Warrington-Seale construction. The latter two examples are also referred to as Seale-Filler construction.

Multiple operation lay strand: Strand construction containing at least two layers of wires, at least one of which is laid in a separate operation. All of the wires are laid in the same direction.

Cross-lay: Multiple operation strand construction in which the wires of superimposed wire layers cross over one another and make point contact, e.g.12/6-1.

Compound lay: Multiple operation strand which contains a minimum of three layers of wires, the outer layer of which is laid over a parallel lay center, e.g.16/6+6-6-1.