HTWR / Dimensions

Wire rope diameter: nominal size, measured size and coated outside diameter

Keep nominal diameter, inspection readings and coating dimensions separate in drawings and inspection records.

Prepared by HTWR · Reviewed 2026-09-28

Reference table

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Illustrative dimension record — not a tolerance recommendation
Field	Example	Meaning
Steel rope nominal diameter	2.0 mm	Specified uncoated rope size
Finished outside diameter	3.0 mm	Size after coating
Ideal radial coating thickness	(3.0 − 2.0) ÷ 2 = 0.5 mm	Concentric geometric example only

Real coating thickness can vary around and along the rope. The arithmetic example does not replace inspection or establish minimum local thickness. Sources and scope ↗

Record how the measurement was made

CERTEX describes checking straight rope sections at two positions at least one metre apart, with two readings at 90° at each position. Confirm the applicable procedure for your product; miniature cut assemblies may need a drawing-specific method.

Avoid mixing coating and steel-core requirements

Put both diameters and their tolerances on the drawing. State coating material, surface needs, cut-end treatment and any stripped length for terminals. Link every inspection record to the same drawing revision.

Common questions

Which diameter belongs in the HTWR breaking-force estimator?

Use the underlying steel rope diameter, not the plastic-covered outside diameter, and only with a supported rope configuration.

Is a nominal 3 mm rope required to read exactly 3.000 mm?

The result must be assessed against the agreed tolerance and measurement procedure. A nominal size alone does not define acceptance limits.

Sources and scope

Reference information supports specification discussions. Confirm the actual supplied product and acceptance criteria with the manufacturing team.