Broken Wire Criteria Indicating Rope Removal

Based on ASME B30.30-2019
Over Length of
6 x Nominal
Rope Diameter
Over a Length of
30 x Nominal
Rope Diameter
B30.30
Rope Type
Standard and Python®
Rope Construction
Within a
Single Strand
Across
All Strands
Across
All Strandsy
Of the Valley
Break Type 1
At End
Termination 2
Running Rope
≤ 6 strands, 19 class 6×19, 4-Runner 3 6 12 2 2
> 6 strands, 19 class Super 8R, 8V, 8C, 8CD, Power 9, Ultra 4 8 16 2 2
≤ 6 strands, 36 class 6×36 5 10 20 2 2
> 6 strands, 36 class 8×36 6 12 24 2 2
Rotation Resistant
Category 1 Compac 35, Compac 35P N/A 6 12 2 2
Category 2 19×7, 19×19, Compac 18 N/A 2 4 2 2
Category 3 Multi N/A 2 4 2 2
Standing Rope
ALL 3 2
GENERAL NOTE: Broken wire rope-removal criteria cited in B30.30 apply to wire rope operating on steel sheaves and cast iron sheaves and drums and wire rope operating on multilayer drums, regardless of sheave material. When drum spooling is single layer, synthetic or sheaves with synthetic linings should not be used because there are no broken wire criteria for this configuration, and internal wire breaks may occur in large numbers before any break or signs of substantial wear are visible on the outside wires of the rope.

Notes:
1) If one valley break is detected, sections of rope 30 x nominal diameter in length on both sides of the detected valley break should be inspected over a bend. For additional information see ASME B30.30-2019, figure 30-0.2-7.

2) Broken wire at end terminations may be eliminated by cutting and reattaching the end termination, if reducing the length is allowable.

Rope Removal and possible Cause

Fault Possible Cause
Accelerated Wear
  • Severe abrasion from being dragged over the ground or obstructions.
  • Rope not suitable for application.
  • Poorly aligned sheaves.
  • Large fleet angle.
  • Worn sheave with improper groove, size or shape.
  • Sheaves and rollers have rough wear surface.
  • Stiff or seized sheave bearings.
  • High bearing and contact pressures.
  • Sheaves/drum too small.
Rapid Appearance of Broken Wires
  • Rope not suitable for application.
  • Reverse bends.
  • Sheaves/drums too small.
  • Overload and shock loads.
  • Excessive rope vibration.
  • Kinks that have formed and have been straightened out.
  • Crushing and flattening of the rope.
  • Sheave wobble.
Corrosion
  • Inadequate lubrication.
  • Improper storage.
  • Exposure to acids or alkalis.
Kinks
  • Improper installation.
  • Improper handling.
  • Slack rope pulled tight.
Excessive Localized Wear
  • Drum crushing.
  • Equalizer Sheave.
  • Vibration.
Stretch
  • Overload.
  • Passed normal stretch and approaches failure.
Broken Wires Near Fitting
  • Rope Vibration.
  • Fittings get pulled too close to sheave or drum.
Sheaves/Drums Wear Out
  • Material too soft.
Pinching, Crushing, Oval Shape
  • Sheaves grooves too small.
  • Not following proper installation and maintenance procedure on multiple layer drums.
Rope Unlays (Opens Up)
  • Wrong rope construction.
  • Rope end attached to swivel.
Reduction in Diameter
  • Broken core.
  • Overload.
  • Internal wear.
  • Corrosion.
Bird Cage
  • Tight Sheaves.
  • Rope is forced to rotate around its own axis.
  • Shock loads.
  • Improper Wedge Socket installation.
Core Protrusion
  • Shock loading.
  • Disturbed rope lay.
  • Rope unlays.
  • Load spins and rotates rope around its own axis.