Coordinated Companies
AS 9100 Aerospace

01 | Wire Rope

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All the Coordinated Wire rope companies supply the highest quality crane ropes made in the USA, Canada and Europe. We specialize in servicing the container cranes in the ports of Long Beach and Los Angeles. Our other emphasis is with Diepa Rope which is one of the oldest and most respected in Europe. We offer Crane ropes for all applications.

In order for a wire rope to be used safely in any application it must be inspected regularly in a proper manner. ASME standards such as B30.5 (mobile cranes) and B30.2 (overhead cranes) are two safety standards that provide detailed inspection procedures and retirement criteria. Both Standards specify that all running ropes should be visually inspected daily. The inspection should be more than just a quick look.

A quick look may not reveal all the evidence of damage or broken wires sufficient to require removal from service. The inspection must be done carefully and in enough light so that broken wires and damage can be observed. Special care should be taken when inspecting portions of the rope subjected to repetitive wear such as the following:

  • Step up and cross over points on the drum
  • Repetitive pick up points
  • Areas of the rope operating through a reverse bend in the reeving system
  • Equalizer sheaves

The inspection should be concerned with determining rope wear or damage which require the rope to be retired or replaced immediately. The inspection should be looking for the following:

  • Distortions such as kinking, crushing, unlaying, birdcaging, strand distortion or core protrusion
  • Corrosion
  • Broken or cut strands
  • Number, type and distribution of broken wires
  • Lubrication condition

General Guidance on Rope Selection

When selecting a steel wire rope to suit a particular application the following characteristics should be taken into consideration.

  • Strength
  • Rotation Resistance
  • Fatigue Resistance
  • Resistance to wear and abrasion
  • Resistance to crushing
  • Resistance to corrosion
  • Rope extension

Strength

The responsibility for determining the minimum strength of a rope for use in a given system rests with the manufacturer of the machine, appliance, or lifting equipment. As part of this process the manufacturer of the machine, appliance or lifting equipment will need to be aware of any local regulations, standards or codes of practice which might govern the design factor of the rope and other factors which might influence the design of sheaves and drums, the shape of the groove profiles and corresponding radius, the drum pitch and the fleet angle, all of which have an effect on rope performance.

Once the strength (referred to as minimum breaking force or minimum breaking load) of the rope has been determined it is then necessary to consider which type of rope will be suitable for the intended duty. It is important therefore for the designer to be fully aware of the properties, characteristics and limitations on use of the many different kinds of steel wire ropes which are available.

Important note for operators
Bridon recommends that once the machine, appliance or lifting equipment has been taken into service, any replacement rope should possess the required characteristics for the duty in question and should, as a minimum, at least comply with the minimum guaranteed breaking force stated by the original equipment manufacturer.

Resistance to Rotation

It is important to determine whether there is a requirement to use a Rotation Resistant rope.

Six or eight strand rope constructions are usually selected unless load rotation on a single part system or "cabling" on a multi-part reeving system are likely to cause operational problems.

When loaded, steel wire ropes will generate:

  • "Torque" if both ends are fixed.
  • "Turn" if one end is unrestrained.

Torque

When both ends of a rope are fixed, the applied force generates "torque" at the fixing points.

Turn

When one end of a rope is free to rotate, the applied load causes the rope to turn.

The torque or turn generated will increase as the load applied increases. The degree to which a wire rope generates torque or turn will be influenced by the construction of the rope. Having recognized what can happen when a rope is loaded it is necessary to select the correct type of rope. It should be noted that all ropes will rotate to some degree when loaded.

The diagram below serves to illustrate the differences in rotational properties between the three basic types of stranded rope.

Standard 6x19 & 6x36 Classification

Diameter Approx Mass
IWRC
EIP Min Breaking Force
IWRC
EEIP Min Breaking Force
IWRC
Inch mm Lb/ft kg/ft Tons kN Tons kN
1/4 0.12 0.05 3.40 30.3
7 0.14 0.06 3.80 34.2 4.2 37.7
5/16 0.18 0.08 5.27 46.9
8 0.18 0.08 5.00 44.7 5.5 49.2
9 0.23 0.11 6.40 56.5 7.0 62.3
3/8 0.26 0.11 7.55 67.2
10 0.29 0.13 7.80 69.8 8.3 76.9
11 0.35 0.16 9.50 84.4 10.5 93.0
7/16 0.35 0.15 10.20 90.7 11.2 99.6
12 0.41 0.19 11.40 101.0 12.4 110.7
1/2 0.46 0.20 13.30 118.4 14.6 129.9
13 0.48 0.22 13.30 118.0 14.6 130.0
14 0.56 0.25 15.40 137.0 17.0 151.0
9/16 0.58 0.26 16.80 149.5 18.5 164.7
5/8 0.72 0.32 20.60 183.3 22.7 202.0
16 0.73 0.33 20.10 179.0 22.1 197.0
18 0.93 0.42 25.40 226.0 28.0 249.0
19 1.03 0.47 28.30 252.0 31.2 278.0
3/4 1.04 0.46 29.40 261.7 32.4 288.4
20 1.15 0.52 31.40 279.0 34.6 308.0
22 1.39 0.63 38.00 338.0 41.8 372.0
7/8 1.41 0.62 39.80 354.2 43.8 389.8
24 1.65 0.75 45.20 402.0 49.8 443.0
1 1.85 0.82 51.70 460.1 56.9 506.4
26 1.94 0.88 53.10 472.0 58.4 520.0
28 2.24 1.02 61.05 547.0 67.8 603.0
1-1/8 2.34 1.03 65.00 578.5 71.5 636.4
1-1/4 2.89 1.28 79.90 711.1 87.9 782.3
32 2.93 1.33 80.40 715.0 88.5 787.0
1-3/8 3.49 1.54 96.00 854.4 106.0 943.4
36 3.71 1.68 101.60 904.0 112.1 997.0
1-1/2 4.16 1.84 114.0 1014.6 125.0 1112.5
40 4.58 2.08 125.90 1120.0 138.3 1230.0
1-5/8 4.88 2.15 132.0 1174.8 146.0 1299.4
44 5.54 2.51 151.7 1350.0 167.4 1489.0
1-3/4 5.66 2.50 153.0 1361.7 169.0 1504.1
1-7/8 6.49 2.86 174.0 1548.6 192.0 1708.8
48 6.60 2.99 181.0 1610.0 199.2 1772.0
2 7.39 3.26 198.0 1762.2 217.0 1931.3

Endurance DYFORM® 18/18PI

  • High strength Rotation Resistant rope incorporating Dyform strands - confirmed by Bridon's "Powercheck" testing of a sample from each production length.
  • Good resistance to rotation - confirmed by Bridon’s unique "Twistcheck" type testing program.
  • Superior bending fatigue life when compared with conventional multistrand ropes - confirmed by laboratory testing and extensive field experience.
  • Excellent resistance to crushing and abrasion resulting from the overall compactness and robustness of the rope and the Dyform strands - recommended when multi-layer spooling is involved.
  • Reduced elongation results from increased steel content and the Dyform process.
  • Optional plastic coating of IWRC to further extend fatigue life, improve structural stability and resistance to corrosion.

Table of sizes, mass and minimum breaking force - Endurance Dyform® 18/18PI

Diameter Approx Mass
WSC
Min Breaking Force
Rope Grade
Dyform
in mm lb/ft kg/ft tons kN
3/8 0.31 0.14 8.3 73.9
10 0.34 0.15 9.5 84.3
11 0.41 0.19 11.8 105.0
7/16 0.42 0.19 11.2 99.70
12 0.49 0.22 13.6 121.0
1/2 0.55 0.24 14.6 129.9
13 0.58 0.26 16.5 147.0
14 0.67 0.30 18.8 167.0
9/16 0.70 0.31 19.2 170.9
5/8 0.86 0.38 22.7 202.0
16 0.88 0.40 24.6 219.0
18 1.11 0.50 31.2 278.0
19 1.23 0.56 34.2 304.0
3/4 1.24 0.55 32.4 288.4
20 1.37 0.62 37.7 335.0
22 1.66 0.75 45.5 405.0
7/8 1.69 0.75 43.8 389.8
24 1.97 0.89 54.2 482.0
1 2.21 0.98 57.5 511.6
26 2.31 1.05 64.3 572.0
28 2.68 1.22 74.4 662.0
1 1/8 2.79 1.23 71.5 636.4
1 1/4 3.45 1.52 87.9 782.3
32 3.50 1.59 96.6 859.0
1 3/8 4.17 1.84 106.0 943.9
1 1/2 4.97 2.19 125.0 1112.5

NOTE: all sizes Powerchecked

Endurance DYFORM® 6/6PI

  • Strongest of all ropes in the six strand product range - confirmed by Bridon's "Powercheck" testing of a sample from each production length.
  • Superior bending fatigue life when compared with conventional six strand ropes - confirmed by laboratory testing and extensive field experience.
  • Excellent resistance to crushing and abrasion resulting from the overall compactness and robustness of the rope and the Dyform strands - recommended when multi-layer spooling is involved.
  • Reduced elongation results from increased steel content and the Dyform process.
  • Optional plastic coating of IWRC to further extend fatigue life, improve structural stability and resistance to corrosion.

Table of sizes, mass and minimum breaking force - Endurance Dyform® 6/6PI

Diameter Approx Mass
WSC
Min Breaking Force
Rope Grade
Dyform
in mm lb/ft kg/ft tons kN
3/8 0.28 0.12 8.8 78.3
10 0.32 0.14 9.6 85.3
11 0.39 0.18 11.0 98.1
7/16 0.38 0.17 11.9 105.9
12 0.44 0.20 12.8 114.0
1/2 0.50 0.22 15.3 136.2
13 0.54 0.24 16.5 147.0
14 0.63 0.29 19.0 169.0
9/16 0.63 0.28 19.3 171.8
5/8 0.78 0.35 22.7 202.0
16 0.79 0.36 24.4 217.0
18 1.03 0.47 30.9 275.0
19 1.12 0.51 33.9 302.0
3/4 1.13 0.50 32.4 288.4
20 1.22 0.55 37.4 333.0
22 1.46 0.66 44.7 398.0
7/8 1.53 0.68 43.8 389.8
24 1.79 0.81 54.7 487.0
1 2.00 0.88 57.5 511.8
26 2.10 0.95 64.7 576.0
28 2.41 1.09 74.7 665.0
1 1/8 2.54 1.12 71.5 636.4
1 1/4 3.13 1.38 87.9 782.3
32 3.15 1.43 94.9 844.0
1 3/8 3.79 1.67 106.0 943.4
36 3.98 1.80 119.1 1060.0
1 1/2 4.51 1.99 125.0 1112.5

NOTE: All sizes Powerchecked

Endurance DYFORM® 8/8PI

High breaking force - confirmed by Bridon’s “Powercheck” testing of a sample from each production length.

Superior bending fatigue life when compared with other conventional eight strand ropes - confirmed by laboratory testing and extensive field experience.
Excellent resistance to crushing and abrasion resulting from the overall compactness and robustness of the rope and the Dyform strands - recommended when multi-layer spooling is involved.
Reduced elongation results from increased steel content and the Dyform process.
Optional plastic coating of IWRC to further extend fatigue life, improve structural stability and resistance to corrosion.

Table of sizes, mass and minimum breaking force - Endurance Dyform® 8/8PI

Diameter Approx Mass
WSC
Min Breaking Force
Rope Grade
Dyform
in mm lb/ft kg/ft tons kN
3/8 0.32 0.14 9.7 86.3
10 0.30 0.14 9.8 87.3
11 0.38 0.17 11.8 105.0
7/16 0.40 0.18 12.4 110.4
12 0.44 0.20 14.2 126.0
1/2 0.51 0.23 16.2 143.7
13 0.52 0.23 16.5 147.0
14 0.60 0.27 19.2 171.0
9/16 0.65 0.29 20.3 180.7
5/8 0.80 0.35 25.0 222.5
16 0.78 0.35 25.2 224.0
18 1.01 0.46 31.8 283.0
19 1.12 0.51 35.5 316.0
3/4 1.16 0.51 36.0 320.4
20 1.24 0.56 39.3 350.0
22 1.49 0.68 47.7 424.0
7/8 1.58 0.70 48.3 429.4
24 1.78 0.81 56.8 505.0
1 2.05 0.91 62.8 558.5
26 2.12 0.96 66.5 592.0
28 2.47 1.12 77.2 687.0
1 1/8 2.60 1.15 79.0 703.1
1 1/4 3.22 1.42 98.0 872.2
32 3.26 1.48 100.8 897.0
1 3/8 3.90 1.72 117.0 1041.3
36 4.07 1.85 127.9 1138.0
1 1/2 4.62 2.04 138.0 1228.2

NOTE: All sizes Powerchecked

Constructex®

  • Nine Strand rope made up of three different strand constructions. Each outside strand manufactured with a soft plastic center.
  • High strength - confirmed by Bridon’s “Powercheck” testing of a sample.
  • Excellent resistance to crushing and wear resulting from the overall compactness and robustness of the rope.
  • Flexible construction with good fatigue life in most applications.

Table of sizes, mass and minimumbreaking force - Constructex®

Diameter Approx Mass Min
Breaking
Force
in lb/ft kg/ft tons kN
5/8 0.9 0.39 25.5 226.9
3/4 1.1 0.50 36.5 324.7
7/8 1.5 0.68 48.5 431.5
1 2.0 0.91 62.5 556.0
1 1/8 2.6 1.18 79.5 707.3
1 1/4 3.2 1.45 97.6 868.3
1 3/8 3.8 1.72 119 1058.7
1 1/2 4.6 2.09 139 1236.7
1 5/8 5.3 2.41 162 1441.3
1 3/4 6.2 2.81 185 1645.9

NOTE: All sizes Powerchecked

Spezialdrahtseile/Special Wire Ropes

The Special Characteristics of DIEPA Special Wire Ropes

  • Only high quality wires are used. The tolerances of these wires are more restricted than those allowed under the standards for wires. Additionally, our suppliers are required to supply wires with higher values in torsion and bending.
  • For ropes with plastic inserts, only that plastic material, which offers the best mechanical and performance capabilities, the polyamide, is selected. And from within the polyamide family only the best performing is used, namely the Polyamide 12.
  • Together with a well known petrochemical company, a special lubricant was developed. This is especially effective against corrosion over a long period of time. The inner parts of the ropes, “the ropes critical area”, are thoroughly bathed with this special lubricant during their individual stranding.
  • Self designed and constructed stranding machines, closing machines, and aggregates provide for highest stranding precision. A very extensive number of modern machinery is available. Therefore, every rope in each of the offered diameters is manufactured with the highest quality, in the most appropriate machine.
  • The different constructions of Diepa Special Wire Ropes are specially designed for specific applications. Our many decades of experience allow us to recommend the most appropriate rope.
  • Because of their special construction and solid structure, Diepa Special Wire Ropes are less affected by higher rope strain from the ropes reeving system, the inappropriate handling of rope, the installing of the rope, or during applications under critical conditions.
  • Long rope life + High rope’s safety throughout service life = Profitability
PRODUCT CODE LAY MINIMUM
BREAKING
GRADE
STRENGTH
D1200
7mm L/RHOL 1960N/mm 9306 pounds
9mm RHOL 1960N/mm 15,399 pounds
10mm RHOL 1960N/mm 19,018 pounds
1/2" RHOL 1960N/mm 30,572 pounds
14mm RHOL 1960N/mm 37,317 pounds
9/16" RHOL 1960N/mm 38,890 pounds
5/8" RHOL 1960N/mm 47,882 pounds
3/4" RHOL 1960N/mm 69,013 pounds
7/8" RHO 1960N/mm 93,966 pounds
1" RHOL 1960N/mm 122,741 pounds
D1315CZ
6mm RHOL 1960N/mm 7441 pounds
8mm RHLL 1960N/mm 13,218 pounds
8mm RHLL (Gal) 2160N/mm 14,207 pounds
9mm RHLL 1960N/mm 16,725 pounds
9mm RHLL 2160N/mm 17,984 pounds
10mm RHLL 1770N/mm 18,524 pounds
10mm RHLL 2160N/mm 22,168 pounds
11mm RHLL 1960N/mm 25,178 pounds
11mm RHLL 2160N/mm 26,976 pounds
12mm RHLL 2160N/mm 31,922 pounds
13mm L/RHLL 2160N/mm 37,766 pounds
14mm RHLL 2160N/mm 43,611 pounds
14mm RHLL(Gal) 2160N/mm 43,611 pounds
16mm RHLL 2160N/mm 57,549 pounds
17mm RHLL 1960N/mm 60,022 pounds
18mm RHLL 2160N/mm 72,610 pounds
19mm L/RHLL(Gal) 2160N/mm 80,478 pounds
20mm RHLL 1960N/mm 83,401 pounds
21mm LHLL 1960N/mm 92,617 pounds
21mm RHLL 2160N/mm 99,362 pounds
22mm RHLL 2160N/mm 109,028 pounds
23mm RHLL 2160N/mm 118,694 pounds
24mm RHLL 2160N/mm 128,810 pounds
25mm RHLL 2160N/mm 137,353 pounds
28mm RHLL 2160N/mm 174,894 pounds
34mm RHLL 2160N/mm 255,373 pounds
B65
26mm RHLL 2160N/mm 154,887 pounds
S321
6mm L/RHOL 1960N/mm 6,564 pounds
7mm L/RHOL 1960N/mm 8,925 pounds
8mm L/RHOL 1960N/mm 9,824 pounds
9mm L/RHOL 1960N/mm 14,229 pounds
11mm L/RHOL 1960N/mm 21,603 pounds
PZ371
1/4" RHOL 1960N/mm 7,149 pounds
5/16" RHOL 1960N/mm 12,500 pounds
3/8" RHOL 1960N/mm 17,900 pounds
10mm RHOL 1770N/mm 17,939 pounds
11mm RHOL 1960N/mm 24,054 pounds
12mm RHOL 1960N/mm 28,744 pounds
1/2" RHOL 1960N/mm 32,000 pounds
9/16" RHOL 1960N/mm 40,500 pounds
5/8" RHOL 1960N/mm 50,000 pounds
3/4" RHOL 1960N/mm 72,000 pounds
7/8" RHOL 1960N/mm 98,100 pounds
1" RHOL 1960N/mm 128,100 pounds
SKZ8
6.5mm RHOL(Gal-Plas) 2160N/mm 10,026 pounds
9mm RHOL(Gal-Plas) 1960N/mm 17,422 pounds
10mm RHOL / Plas 2160N/mm 23,829 pounds
11mm RHOL 2160N/mm 28,744 pounds
12mm RHOL 1960N/mm 30,573 pounds
13mm RHOL 1960N/mm 35,743 pounds
14mm RHOL 1960N/mm 42,038 pounds
16mm RHOL 2160N/mm 60,696 pounds
18mm RHOL 1960N/mm 69,913 pounds
19mm RHOL 2160N/mm 84,750 pounds
20mm RHOL 2160N/mm 94,641 pounds
22mm RHOL 1960N/mm 105,431 pounds
24mm RHOL 2160N/mm 136,229 pounds
25mm RHOL 2160N/mm 146,794 pounds
28mm RHOL 2160N/mm 184,786 pounds
Super 24
3/4" RHOL 2160N/mm 81,827 pounds
7/8" RHOL 2160N/mm 111,286 pounds

Contact your Coordinated Companies representative and ask for the recommended Diepa crane rope foryour particular needs. We have the right rope for virtually any application and would be happy to assist youin choosing a crane rope that will give you the most service for your money.

Typical Examples of Wire Rope Deterioration

Mechanical damage due to rope movement over sharp edge projection while under load
Localized wear due to abrasion on supporting structure.
Narrow path of wear resulting in fatigue fractures, caused by working in a grossly oversize groove, orover small supportrollers.
Two parallel paths of broken wires indicative of bending through an undersize groove in the sheave.
Severe wear, associated with high tread pressure.
Severe wear in Langs Lay, caused by abrasion.
Severe corrosion.
Internal corrosion while external surface shows little evidence of deterioration.
Typical wire fractures as a result of bend fatigue.
Wire fractures at the strand, or core interface, as distinct from ‘crown’ fractures.
Break up of IWRC resulting from high stress application.
Looped wires as a result of torsional imbalance and/or shock loading.
Typical example of localized wear and deformation.
Multi strand rope ‘bird caged’ due to torsional imbalance.
Protrusion of rope center resulting from build up of turn.
Substantial wear and severe internal corrosion.

Troubleshooting Guide


The following is a simplified guide to common wire rope problems. In the event of no other standard being applicable, it is recommended that ropes are inspected/examined in accordance with ASME B30.5.


Problem Cause/Action
Mechanical damage caused by the rope contacting the structure of the crane on which it is operating or an external structure - usually of a localized nature.
  • Generally results from operational conditions.
  • Check sheave guards and support/guide sheaves to ensure that the rope has not "jumped out" of the intended reeving system.
  • Review operating conditions.
Opening of strands in Rotation Resistant ropes - in extreme circumstances the rope may develop a “birdcage distortion” or protrusion of inner strands.
Note - Rotation Resistant ropes are designed with a specific strand gap which may be apparent on delivery in an off tension condition. These gaps will close under load and will have no effect on the operational performance of the rope.
  • Check sheave and drum groove radii using sheave gauge to ensure that they are no smaller than nominal rope radius +2.5% - Bridon recommends that the sheave and drum groove radii are checked prior to any rope installation.
  • Repair or replace drum/sheaves if necessary.
  • Check fleet angles in the reeving system - a fleet angle in excess of 1.5 degrees may cause distortion (see page 95).
  • Check installation method - turn induced during installation can cause excessive rope rotation resulting in distortion (See pages 86 to 90).
  • Check if the rope has been cut “on site “ prior to installation or cut to remove a damaged portion from the end of the rope. If so, was the correct cutting procedure used? Incorrect cutting of Rotation Resistant, low rotation and parallel closed ropes can cause distortion in operation (See page 88 to 89).
  • Rope may have experienced a shock load.
Broken wires or crushed or flattened rope on lower layers at crossover points in multi - layer coiling situations.
Wire breaks usually resulting from crushing or abrasion.
  • Check tension on underlying layers. Bridon recommends an installation tension of between 2% and 10% of the minimum breaking force of the wire rope. Care should be taken to ensure that tension is retained in service. Insufficient tension will result in these lower layers being more prone to crushing damage.
  • Review wire rope construction. Dyform wire ropes are more resistant to crushing on underlying layers than conventional rope constructions.
  • Do not use more rope than necessary.
  • Check drum diameter. Insufficient bending ratio increases tread pressure.
Wires looping from strands.
  • Insufficient service dressing.
  • Consider alternative rope construction.
  • If wires are looping out of the rope underneath a crossover point, there may be insufficient tension on the lower wraps on the drum.
  • Check for areas of rope crushing or distortion.
  • Possible fleet angle problems causing rope rotation.
"Pigtail" or severe spiralling in rope.
  • Check that the sheave and drum diameter is large enough - Bridon recommends a minimum ratio of the drum/sheave to nominal rope diameter of 18:1.
  • Indicates that the rope has run over a small radius or sharp edge.
  • Check to see if the rope has "jumped off" a sheave and has run over a shaft.
Two single axial lines of broken wires running along the length of the rope approximately 120 degrees apart indicating that the rope is being "nipped" in a tight sheave.
  • Cheack sheave and drum groove radii using sheave gauge to ensure that they are no smaller than nominal rope radius + 2.5% - Bridon would recommend that the sheave/drum groove radii are checked prior to any rope installation.
  • Repair or replace drum/sheaves if necessary.
One line of broken wires running along the length of therope indicating insufficient support for the rope, generallycaused by oversize sheave or drum grooving.
  • Check to see if the groove diameter is no greater than15% greater than the nominal rope diameter.
  • Repair or replace drum/sheaves if necessary.
  • Check for contact damage.
Short rope life resulting from evenly/randomly distributedbend fatigue wire breaks caused by bending through thereeving system.
Fatique induced wire breaks are characterized by flat endson the broken wires.
  • Bending fatigue is accelerated as the load increases and asthe bending radius decreases (see page 74). Considerwhether either factor can be improved.
  • Check wire rope construction - Dyform ropes are capableof doubling the bending fatigue life of a conventionalsteel wire rope.
Short rope life resulting from localized bend fatigue wirebreaks.
Fatique induced wire breaks are characterized by flat endson the broken wires.
  • Bending fatigue is accelerated as the load increases and asthe bending radius decreases (see page 74). Considerwhether either factor can be improved.
  • Check wire rope construction - Dyform ropes are capableof doubling the bending fatigue life of a conventionalsteel wire rope.
  • Localized fatigue breaks indicate continuous repetitivebends over a short length. Consider whether it iseconomic to periodically shorten the rope in order tomove the rope through the system and progressivelyexpose fresh rope to the severe bending zone. In orderto facilitate this procedure it may be necessary to beginoperating with a slightly longer length of rope.
Broken rope - ropes are likely to break when subjected tosubstantial overload or misuse particularly when a rope hasalready been subjected to mechanical damage.
Corrosion of the rope both internally and/or externallycan also result in a significant loss in metallic area. Therope strength is reduced to a level where it is unable tosustain the normal working load.
  • Review operating conditions.
Wave or corkscrew deformations normally associated withmultistrand ropes.
  • Check sheave and drum groove radii using sheave gaugeto ensure that they are no smaller than nominal roperadius +2.5% - Bridon recommends that the sheave/drumgroove radii are checked prior to any rope installation.
  • Repair or replace drum/sheaves if necessary.
  • Check fleet angles in the reeving system - a fleet angle inexcess of 1.5 degrees may cause distortion (see page 76)
  • Check that rope end has been secured in accordance withmanufacturers instructions (see page 88 & 89).
  • Check operating conditions for induced turn.
Rotation of the load in a single fall system.
  • Review rope selection.
  • Consider use of Rotation Resistant rope.
Rotation of the load in a multi - fall system resulting in“cabling” of the rope falls.
Possibly due to induced turn during installation oroperation.
  • Review rope selection (see page 76 to 78 cabling calc.)
  • Consider use of Rotation Resistant rope.
  • Review installation procedure (see page 87 to 90) oroperating procedures.
Core protrusion or broken core in single layer six or eightstrand rope.
  • Caused by repetitive shock loading - review operatingconditions.
Rope accumulating or “stacking” at drum flange - due toinsufficient fleet angle.
  • Review drum design with original equipmentmanufacturer - consider adding rope kicker, fleetingsheave etc.
Sunken wraps of rope on the drum normally associatedwith insufficient support from lower layers of rope orgrooving.
  • Check correct rope diameter.
  • If grooved drum check groove pitch.
  • Check tension on underlying layers - Bridon recommendan installation tension of between 2% and 10% of theminimum breaking force of the wire rope - Care shouldbe taken to ensure that tension is retained in service.Insufficient tension will result in these lower layers beingmore prone to crushing damage.
  • Make sure that the correct rope length is being used. Toomuch rope (which may not be necessary) may aggravatethe problem.
Short rope life induced by excessive wear and abrasion.
  • Check fleet angle to drum.
  • Check general alignment of sheaves in the reeving system.
  • Check that all sheaves are free to rotate.
  • Review rope selection. The smooth surface of Dyformwire ropes gives better contact with drum and sheaves andoffers improved resistance to “interference” betweeenadjacent laps of rope.
External corrosion.
  • Consider selection of galvanized rope.
  • Review level and type of service dressing.
Internal corrosion.
  • Consider selection of galvanized rope.
  • Review frequency amount and type of service dressing.
  • Consider selection of plastic impregnated (PI) wire rope.

Decimal & Metric Conversion Table


Fractional
Equivalent
(In)
Decimal
Equivalent
(In)
Metric
Equivalent
(mm)
1/64 .0156 .397
1/32 .0312 .794
3/64 .0469 1.191
1/16 .0625 1.588
5/64 .0781 1.984
3/32 .0938 2.381
7/64 .1094 2.778
1/8 .1250 3.175
9/64 .1406 3.572
5/32 .1562 3.969
11/64 .1719 4.366
3/16 .1875 4.762
13/64 .2031 5.159
7/32 .2188 5.556
15/64 .2344 5.953
1/4 .2500 6.350
17/64 .2656 6.747
9/32 .2812 7.144
19/64 .2969 7.541
21/64 .3281 8.334
11/32 .3438 8.731
23/64 .3594 9.128
3/8 .3750 9.525
25/64 .3906 9.922
13/32 .4062 10.319
27/64 .4219 10.716
7/16 .4375 11.112
29/64 .4531 11.509
15/32 .4688 11.906
31/64 .4844 12.303
1/2 .5000 12.700
33/64 .5156 13.097
17/32 .5312 13.494
35/64 .5469 13.891
9/16 .5625 14.288
37/64 .5781 14.684
19/32 .5938 15.081
39/64 .6094 15.478
5/8 .6250 15.875
41/64 .6406 16.272
21/32 .6562 16.669
43/64 .6719 17.065
11/16 .6875 17.462
45/64 .7031 17.859
23/32 .7188 18.256
47/64 .7344 18.653
3/4 .7500 19.050
49/64 .7656 19.447
25/32 .7812 19.844
51/64 .7969 20.241
13/16 .8125 20.638
53/64 .8281 21.034
27/32 .8438 21.431
55/64 .8594 21.828
7/8 .8750 22.225.
57/64 .8906 22.622
29/32 .9062 23.019
59/64 .9219 23.416
15/16 .9375 23.812
61/64 .9531 24.209
31/32 .9688 24.606
1 1.000 25.400