This paper focuses on the technical system of the wire rope's full life cycle. Based on current nationandards such as GB/T 20118-2025 "General Technical Conditions for Wire Ropes" and GB/T6-2017 "Wire Ropes - Terminology, Marking and Classification," it provides a professional discussion across six dimensions: material structure, manufacturing process, performance parameters, selection and matching, in maintenance, and scrapping standards. It covers the technical key points of the entire process, including design, production, use, and management.

Wire Rope Full Life Cycle Technology and Application Spifications (Professional Edition)

I. Basic Definitions and Core Composition

A wire rope is a flexible load-bearing component formed by twisting, compacting, and pre-deforming high-carbonsteel wires.

It possesses high tensile strength, good flexibility, and impact toughness. As the core load-bearing part of hoisting, lifting, traction, and tensioning systems, widely used in mining, ports, elevators, cableways, and construction machinery fields.

1. Core Components

-Wire: Made of high-quality high-carbon steel (carbon ontent 0.60%~0.95%), processed through cold drawing and heat treatment.

Nominal tensile strength grades cover 1570Pa, 1670MPa, 1770MPa, 1960MPa, 2060MPa (2060MPa grade aded in GB/T 20118-2025).

Diameter ranges from 0.4mm to 6.0mm. Surface types include bright, galvanized, zinc-alalloy coated, and plastic coated, with coatings meeting the corrosion protection requirements of GB/T 1839.

-Strand: Twisted from multiple wires around a central wire. Tnclude round strand, triangular strand, flat strand, and compacted strand.

Compacted strands (K) are formed through die drawing/rolling/forging, increasing fillig rate by 15%~25% and significantly enhancing wear and crush resistance.

-Core: Provides load-bearing support, oil storage for lubrication, and shock absorption. Divided into threcategories:

-Fiber Core (FC): Natural sisal, synthetic polypropylene/polyester. Oil content 8%~16%. Good flexibility and vibration damping, temperature esistance ≤100℃. Suitable for light loads and low speeds.

-Steel Core: Independent Wire Rope Core (IWRC), Parallel Wire Rope Core (PWRC), Wire Strand (WSC). High strength, crush resistance, temperature resistance up to 200℃. Suitable for multi-layer winding and heavy load conditions.

-Composite Core: Encapsulated Poymer IWRC (EPIWRC). Combines the strength of steel cores with the lubrication of fiber cores. Suitable for precision applications such as elevators and cableways.

2. Cog Parameters

-Lay Length: The axial distance for the outer strands/wires to make one complete turn around the axis. National standards specify wire rope lay length75 times the nominal diameter, and parallel wire rope core ≤7.5 times.

-Lay Direction: Divided into right lay (Z) and left lay (S). Stran types:

-Lang Lay (sZ/zS): Strand lay direction is opposite to rope lay direction. Non-loosening, anti-rotation. Most widely applied.

-RegulaLay (zZ/sS): Strand lay direction is the same as rope lay direction. Good flexibility and wear resistance, prone to loosening. Requires end fixation during use.

-Mixed Lay: Combines aages of both, suitable for special working conditions.

II. Structural Classification and Performance Matching (GB/T 806-2017)

1. Classification by Strand Structure

-Point Contact Wire Rope: Wires cross-contact, stress concentration, prone to fatigue; representative structures37; suitable for static tensioning and general lifting;

-Line Contact Wire Rope: Wires parallel and in contact, uniform stress, excellent fatigue resistance; divided into le (S), Warrington (W), and Filled (Fi) types; representative structures 6×19S, 6×36WS; suitable for mainstream lifting and hoisting os;

-Compact Strand Wire Rope: Strands undergo compacting treatment, high density, wear-resistant, and crush-resistant; marked with "K", eg., 6×36WSK; used for heavy loads in ports and mines;

-Non-rotating Wire Rope: Multi-layer strands reverse-laid, rotation ≤4r/1000d; representativ structures 18×7, 24×7, 35W×7; suitable for high-altitude lifting and deep-well hoisting.

2. Specialized Clification by Application

-Elevator Rope:GB 8903-2024, structures 8×19S, 8×25Fi; / composite core; uniform lay, stable elongation;

-Mine Hoisting Rope: GB 8918, triangular strands, compact strands; corrosion-resistant and fatigue-resistant; suitab underground environments;

-Cableway Rope: GB 26722-2024, high toughness, high corrosion resistance; meets safety requirements for carrying.

-Passengerilfield Rope: GB/T 40089, high-temperature resistant, hydrogen sulfide resistant; suitable for oil and gas extraction conditions.

III. Manufacturing Process and Quali Control (GB/T 20118-2025)

1. Standard Process Flow

Raw material inspection → Wire drawing → Heat treatment → Coating treatment → Stra stranding → Rope closing → Pre-deformation → Post-deformation → Compacting → Pre-tensioning → Oil coating → Rope end treatment → Finished product inspection

2. Key Pros Points

Pre-deformation / Post-deformation: Eliminate internal stresses, ensure the wire rope does not loosen or have a wavy shape; must be performed on all finished r Pre-tensioning: Loaded to 55% of the minimum breaking force, eliminate structural elongation, ensure dimensional stability;

Oil Coating: Apply special lubricating grease durinranding; oil content of outer strands 0.60%~2.00%; for corrosion protection, wear reduction, and oil storage;

Wire Splicing: For iameter >0.4mm, use butt welding; splice spacing ≥10m; ensure continuity; Rope End Treatment: Binding or fusion welding fixation; prevent loosening; diameter increasut end meets national standard limits.

3. Core Quality Indicators

-Diameter Deviation: Nominal diameter d>10mm, 5%~0 unoaded, 0~-1% at 10% breaking force;

-Non-loosening: After removing two strands and resetting, no spontaneous loosening occurs;

-Breaking Force: Measured value ≥ nominal minieaking force, measured according to GB/T 8358;

-Wire Performance: Meets tensile, repeated bending, and torsion test requirements; coating weight meets stan Performance Parameters and Calculation Methods

IV. Performance Parameters and Calculation Methods

1. Core Mechanical Parameters

-Minimum Breaking Force (F₀): F₀ = × D² × R₀ / 1000 (K: Structural Coefficient, D: Nominal Diameter mm, R₀: Nominal Tensile Strength of Wire MPa);

-Safty Factor (n): n = F₀ / W (W: Working Tension), National Standard Mandatory Requirements: General Lifting ≥ 5; Passenger Elevators ≥ine Hoisting ≥ 9; Cableways ≥ 12;

-Elongation: Structural Elongation ≤ 0.5%, Elastic Elongation complies ith GB/T 43357;

-Weight: Reference Weight = Coefficient × D² (Coefficient is looked up in the table according to structure, unit kg/100m).

2. Emental Adaptability

-Temperature: Fiber core ≤ 100°C, steel core ≤ 200°C; derating is required for overheating;

-Corrosion Resist: Select galvanized or zinc-aluminum alloy coating for marine and acid-alkali environments; select plastic-coated wire rope for industrial dust environments;

-Wear Resistance: Larger diameter out and compacted structures provide better wear resistance.

V. Selection Specifications and Scenario Matching

1. Core Logic of Model Selection

2. Typical Scenario Selection Table

3. Selection Taboos

-Fiber core is prohibited for multi-layer winding; steel core / compacted strand must be selected;

-Anti-rotation ropes must e mixed with ordinary ropes; deviation angle ≤2°;

-Smooth ropes are prohibited in corrosive environments; galvanized / plastic-coated ropes must be selected.

VI. Specifications for Use, Maintenance, and Inspection (GB/T 29086-2012)

1. Installation and Usage Reqrements

2. Maintenance and Care Points

-Lubrication: Apply specialized grease every 3-6 months, compatible with manufacturing grease, and spray at highto penetrate the interior;

-Cleaning: Remove dust, rust, and debris to prevent abrasive wear;

-Tension Balance: Regularly adjust tension in multi-rope systems, with dev≤5%;

-Storage: Store in a dry and ventilated area, elevated off the ground, protected from rain, corrosion, and high temperatures, and follow "First In,First Out".

3. Inspection Methods and Frequency

-Daily Inspection: Visual inspection for broken wires, wear, corrosion, deformation, and core extrusion;

-Periodic Inspection: Measdiameter and lay length monthly; perform non-destructive testing quarterly;

-Non-Destructive Testing: Primarily magnetic flux leakage testing, for quantitative identification of broken wires, wear, and corrosion, suitable for critical scenarios such as mining and elevators;

-Diameter Measurement: Use a wide-jaw caliper, measure at a point more than 15m fend, measure two perpendicular cross-sections, and take the average value.

VII. Scrapping Standards and Safety Management (GB/T 5972)

In the event of any of the following conditions, the wire rope shall beely scrapped, and repair and continued use are strictly prohibited:

1. Excessive broken wires: The number of broken wires in any lay reaches 10% of the total numer of wires, or there is localized concentration of broken wires or a sudden increase in broken wires;

2. Diameter wear: The measured diameter is reduced by ≥6% (critical senarios) / 10% (general scenarios) compared to the nominal diameter;

3. Structural damage: Loose strands, extrusion of the core, "birdcage" deformati kinking, or flattening;

4. Severe corrosion: Pitting, pockmarks, or rusting depth ≥10% of the original diameter;

5. Excessivee: Arc burns, high-temperature annealing, or irreversible plastic deformation;

6. Insufficient safety factor: The calculated safety factor is below the national standards.

VIII. Standard System and Development Trends

1. Core National Standard System

-General Foundation: GB/T 20118-2al Technical Requirements), GB/T 8706-2017 (Terminology Classification);

-Specialized Products: GB8903-2024 (Elevators), GB 26722-2024 (Ropeways), GB 8918 (Important Applications);

-SafeUse: GB/T 29086-2012 (Use and Maintenance), GB/T 5972 (Crane Scrapping).

2. Technology Development Trends

-High-strength: Large-scale application of steel wires of 2060 MPa and above, reducing self-weight and improving load-bearing capacity;

-Intelligent: Built-in sensor steel wire ropes to monitor tension, temperature and damage in real time;

-Long service life: Adopting composite coating, nano-lubrication and precise compaction technology to extend service life by over 50%;

-Green development: Eco-friendly coating, recyclable rope core and low-toxic grease, in line with the dual-carbon goals.

IX. Conclusion