Terminology#

Makes

  • Cable laid wire rope (sling/grommet)

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  • 6x36 Wire rope with steel core (Independent Wire Rope Core)

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Steel#

Steel-wire rope

  • Wire is a metal thread.

  • Several wires are combined into a strand.

  • Strands are bound together around a core to make a rope.

If this is the end-product, then it typically referred to in combination with its construction and/or material. For example a “wire rope”, “steel-wire rope”.

  • A typical product is the 6x36 IWRC (Independent Wire Rope Core )

image-20230530125058469

Cable-laid rope

The same steps are repeated to create a cable-laid sling or grommet.

The ropes are now used as strands and are referred to as unit-ropes and the end product is cable-laid rope.

In general terms, cable is used to refer to a strong rope.

Synthetic Fiber#

Synthetic ropes are ropes assembled from synthetic fibers (as opposed to natural fibers).

Examples are nylon, polyester, HMPE (high modulus polyethylene). Dyneema® and Spectra® are brand names and are specific types of HMPE.

Grommets#

A special mention of grommet, because it is easy to confuse properties like length and MBL.

The typical configuration of a grommet and terminology is shown below:

image-20230530125414822

the MBL of a grommet is typically referred to a twice that of the parts (IMCA defines the breaking load as 12 times that of the unit ropes and a correction for spinning losses).

In DAVE#

In DAVE a Cable is a node that can be used to model any flexible member without a bending stiffness and without compression. When modelling rigging, a Cable node is used to model the rope or cable-laid rope.

A SlingGrommet Node can be used to model a complete sling or grommet. In that case the MBL of a grommet is given in line with IMCA, so for the grommet used in typical configuration.