What Does Inner Wire Diameter Mean in PVC Coated Rockfall Netting?

In PVC coated rockfall netting, inner wire diameter means the diameter of the steel wire before the PVC coating is applied. It describes the base wire inside the plastic coating layer.

This number should not be confused with the coated outside diameter. PVC coating adds material around the wire, so the outside diameter after coating is larger than the inner steel wire diameter.

Inner Wire Diameter Is the Base Steel Wire Size

The inner wire is the steel wire inside the PVC layer. Its diameter is measured before the outer PVC coating is counted.

For example, if a PVC coated rockfall netting specification is written as 2.7/3.7mm, the 2.7mm part normally refers to the inner wire diameter. It tells the buyer the size of the base steel wire.

This is different from simply saying "3.7mm wire". Without the inner wire information, the base wire size may be unclear.

Coated Outside Diameter Is a Different Number

Coated outside diameter means the finished outside diameter after PVC coating.

In the same 2.7/3.7mm example:

These two numbers describe different parts of the finished wire. The first number explains the inner steel wire. The second number explains the outer coated size.

Why the Two Numbers Should Not Be Mixed

PVC coated rockfall netting can be misunderstood when only one wire number is used.

If a buyer sees only 3.7mm, it may be unclear whether this is the inner steel wire diameter or the coated outside diameter. If a buyer sees only 2.7mm, it may be unclear what the final coated size is.

A clearer expression is:

2.7mm inner wire / 3.7mm coated diameter

When mesh opening is also included, the specification becomes clearer:

2.7mm inner wire / 3.7mm coated diameter, 80x100mm mesh opening

Inner Wire Diameter Does Not Describe the Whole Roll

Inner wire diameter is important, but it is only one part of the PVC coated rockfall netting specification.

The finished roll should also be read together with mesh opening, coated outside diameter, base wire coating, PVC coating condition, selvedge wire if specified, roll width and roll length.

For product context, the PVC coated rockfall netting page is the main product reference. For a broader coating discussion, see the rockfall netting coating comparison.

Read as a term, inner wire diameter means the diameter of the steel wire inside the PVC coating. In PVC coated rockfall netting, it should be stated separately from the coated outside diameter so the base wire size and finished coated size are not mixed.