Diameter and tolerance

Lifting Knowhow Logo

How to measure wire diameter correctly


The wire diameter should always be checked before installation. Measure on a straight section of the wire. Two sections with a minimum distance of one meter should be measured. At each point, two measurements should be taken with a 90-degree offset from each other. The average between the two measurements should comply with the tolerance described in the tables below.

Correct way to measure steel wire rope thickness
Correct way of measuring

Wrong way to measure steel wire rope thickness
Wrong way of measuring

Steel wire ropes for general applications

Nominal Rope
Dia (mm)
Percentage (%)
2 to <4 0 +8
4 to <6 0 +7
6 to <8 0 +6
8 and up 0 +5

Tolerance of nominal diameter on unloaded rope.

Nominal Rope
Dia (mm)
Rope with strands
that are exclusively
of wire max. %
Rope with strands
that incorporate fibre
centres max. %
2 to <4 +7 -
4 to <6 +6 +8
6 to <8 +5 +7
8 and up +4 +6

Tolerance of nominal diameter by unloaded rope.

Steel wire ropes for person elevators

Tolerance for nominal diameter for ropes with fiber/synthetic core.

  Unloaded Loaded to 5% of min.
breaking load
Loaded to 10% of min.
breaking load
Nominal Rope
Dia (mm)
max. % min. % min. %
=10 +6 +1 0
<10 +5 +1 0

Tolerance for nominal diameter for ropes with steel core.

  Unloaded Loaded to 5% of min.
breaking load
Loaded to 10% of min.
breaking load
Nominal Rope
Dia (mm)
max. % min. % max. %
=10 +3 0 -1
<10 +2 0 -1

 

Difference between two measurements expressed as percentage of nominal diameter under a load equivalent to 5% or 10% of min. breaking load.

Nominal Rope
Dia (mm)
Rope ovality
max. %
Average diameter variation
max. %
<8 +4 +3
8 and up +3 +2

Do you wish to know more about our Lifting KnowHow? Please reach out.

For faster response, call us directly at +47 66 79 95 00!

Installation of steel wire rope

Learn more about installation of your steel wire rope

Technical description of steel wire rope

Learn more about steel wire rope applications

Diameter and tolerance of steel wire rope

Learn more about tolerance of steel wire rope

Discarding of steel wire rope

Learn more about the correct ways of discarding steel wire rope

Composition of steel wire rope

Learn more about the composition of steel wire rope

Factors to Consider When Selecting Your Wire Rope

Learn more about how to choose the right steel wire rope