Mining Wire Rope: Definition, Inspection, Safety Factor, and Certification

1. Definition of Mining Wire Rope

Mining wire rope refers to steel wire ropes used in mines and underground mining operations. In a narrow sense, mining wire rope usually refers specifically to coal mine wire rope. Mining wire rope is a critical material for coal production and is one of the most important steel products used in the coal industry.

The coal industry is a key pillar of economic development. China is one of the world’s largest coal producers, with an annual raw coal output exceeding hundreds of millions of tons. As a result, the annual consumption of mining wire rope in China reaches 50,000–60,000 tons, ranking first globally.

Due to the high safety risks involved, many countries place great importance on the quality of mining wire ropes. International standards for mining wire ropes have been established by countries such as Germany, the United Kingdom, Sweden, Japan, and Australia.

Internationally, mining wire ropes are mainly used in:

• Mine hoisting systems

• Underground and surface hauling

• Mining excavation equipment

• Guide ropes for shafts

• Mining winches

• Continuous conveying systems

2. Inspection of Mining Wire Rope

Before mining wire rope is delivered from the manufacturer to the mine for use, it must undergo strict inspection, including acceptance inspection and in-service inspection. The purpose of inspection is to verify whether the wire rope meets mining standards and safety requirements. Unqualified wire ropes are strictly prohibited from being used in mining operations.

All inspections must comply with the requirements of the Coal Mine Safety Regulations.

Acceptance Inspection

When a new mining wire rope arrives at the mine site, the mine’s safety management personnel should entrust certified inspection agencies or quality supervision departments to inspect the wire rope according to mining wire rope standards. The inspection includes:

• External appearance

• Rope construction and lay characteristics

• Mechanical properties of the steel wires

In-Service Inspection

Regular inspection during use is particularly important due to the harsh underground environment. Factors such as:

• Acidic or alkaline mine conditions

• Lubricant loss

• Corrosion of steel wires

• Accelerated wear

will continuously affect the performance of the wire rope in service.

Visual inspection involves checking both the internal structure and the external condition of the wire rope. In addition, strand removal testing is required.

Strand Removal Test Requirements

• Personnel hoisting wire ropes:
  Strand removal testing should be conducted every six months, including tensile strength, torsion, and bending tests of the steel wires.

• Material hoisting wire ropes:
  Strand removal testing should be conducted one year after installation, and then every six months thereafter.

3. Safety Factor of Mining Wire Rope

The safety factor of a mining wire rope is defined as the ratio between:

• The sum of the breaking forces of all qualified steel wires (excluding unqualified test samples), and

• The maximum static tensile load applied to the wire rope.

For new or in-service wire ropes, the total breaking force must be calculated based on test data provided by certified wire rope inspection centers. The maximum static tensile load must be accurately calculated, not estimated.

According to the implementation guidelines of the national coal mine safety regulations, the safety factor of newly installed lifting and suspension wire ropes must comply with relevant requirements.

Typical safety factor recommendations include:

• Mine hoisting in vertical and inclined shafts: minimum safety factor 5

• Industrial lifting applications: minimum safety factor 6

• Single-rope winding hoisting systems for personnel and materials: minimum safety factor 9

4. Length Measurement and Acceptance of Mining Wire Rope

The length of mining wire rope is measured in meters. The method for measuring wire rope length should be agreed upon by both the supplier and the purchaser.

For new wire ropes measured under no-load conditions, allowable length tolerances are:

• ≤400 meters: +0% to +5%

• >400 meters: +0 to +20 meters

5. Certification Requirements for Mining Wire Rope

Mining wire rope must be certified with appropriate safety approvals. Since mining operations involve extremely high risk, mining wire ropes generally fall under the category of wire ropes for important applications.

Mining wire ropes are used in various types of mines, including:

• Coal mines

• Iron ore mines

• Limestone mines

• Nickel mines

• Copper mines

• Gold and silver mines

• Rare earth mines

Among them, coal mine wire ropes must hold the MA (Mining Safety Approval) certification.

Common mining wire rope constructions include:

• Line contact wire ropes

• Surface contact wire ropes

Coal mines include both vertical shafts and inclined shafts. Historically, fine-wire ropes were used in vertical shafts and coarse-wire ropes in inclined shafts due to higher wear in inclined applications. With advancements in wire rope structure design, line-contact coarse wire ropes are now widely used for both shaft types. In some vertical shaft applications, rotation-resistant wire ropes are also employed.

Conclusion

Mining wire rope plays a vital role in ensuring the safety and efficiency of mining operations. Due to the harsh working environment and high safety risks, mining wire ropes are subject to strict inspection, high safety factor requirements, precise length control, and mandatory certification. Selecting compliant, certified, and properly inspected mining wire ropes is essential for safe mine operation.

If you require certified mining wire ropes for coal mines or other mining applications, please contact us for professional guidance and product support.