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Figure 4: Viper Mk II applying 1235 Almatek - Netherlands

Petroleum and vegetable oils penetrate best and are the easiest to apply because proper additive design of these penetrating types gives them excellent wear and corrosion resistance. The fluid property of oil type lubricants helps to wash the rope to remove abrasive external contaminants.

Wire ropes are lubricated during the manufacturing process. If the rope has a fibre core center, the fibre will be lubricated with a mineral oil or petrolatum- type lubricant. The core will absorb the lubricant and function as a reservoir for prolonged lubrication while in service.

If the rope has a steel core, the lubricant (both oil and grease type) is pumped in a stream just ahead of the die that twists the wires into a strand. This allows complete coverage of all wires.

After the cable is put into service, re-lubrication is required due to loss of the original lubricant from loading, bending and stretching of the cable. The fibre core cables dry out over time due to heat from evaporation, and often absorb moisture. Field re-lubrication is necessary to minimise corrosion, protect and preserve the rope core and wires, and thus extend the service life of the wire rope.

If a cable is dirty or has accumulated layers of hardened lubricant or other contaminants, it must be cleaned with a wire brush and petroleum solvent,


compressed air or steam cleaner before re-lubrication. The wire rope must then be dried and lubricated immediately to prevent rusting. Field lubricants can be applied by spray, brush, dip, drip or pressure boot. Lubricants are best applied at a drum or sheave where the rope strands have a tendency to separate slightly due to bending to facilitate maximum penetration to the core. If a pressure boot application is used, the lubricant is applied to the rope under slight tension in a straight condition. Excessive lubricant application should be avoided to prevent safety hazards.

Key Lubricant Performance Measures Some key performance attributes to look for in a wire rope lubricant are wear resistance and corrosion prevention. Some useful performance benchmarks include high four-ball EP test values, such as a weld point (ASTM D2783) of above 350 kg and a load wear index of above 50. For corrosion protection, look for wire rope lubricants with salt spray (ASTM B117) resistance values above 60 hours and humidity cabinet (ASTM D1748) values of more than 60 days. Most manufacturers provide this type of data on product data sheets.

Factors that Influence Wire Rope and Cable Performance

Cable life cycle and performance are influenced by several factors, including type of operation, care and environment. Cables can be damaged by worn sheaves, improper winding and splicing practices,

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