Nylon-Coated Steel Wire Rope Extrusion Line

Nylon-Coated Steel Wire Rope Extrusion Line

The Nylon-coated steel wire rope extrusion production line is a specialized automated complete set of equipment used to continuously and uniformly coat a layer of nylon (PA, such as PA6, PA66) plastic onto the surface of bare steel wire rope. Its core process utilizes a plastic extruder to tightly coat molten nylon material onto the steel wire rope moving at a constant speed. After cooling and setting, the final nylon-coated steel wire rope product is formed.
The nylon coating combines multiple excellent properties, performing outstandingly in specific applications:
Excellent Abrasion Resistance: Nylon's wear resistance is second only to PU, ranking among the top of all engineering plastics, far higher than PE and PVC.
High Strength and Toughness: Possesses high mechanical strength, tensile strength, and impact resistance, capable of withstanding heavy loads and impact.
Good Temperature Resistance: Has a wider usage temperature range than PE and PVC, with particularly better heat resistance (e.g., the heat deflection temperature of Nylon 66 can exceed 200°C).
Low Coefficient of Friction: The surface is smooth with good self-lubrication, resulting in low operating resistance and less noise generation.
Oil and Chemical Resistance: Offers good resistance to oils, fuels, and many chemical solvents.
Fatigue Resistance: Maintains performance under repeated bending and loading.

Production Line Composition

A complete nylon-coated steel wire rope extrusion production line requires specialized design to address the characteristics of nylon, such as strong hygroscopicity, high melting point, low melt viscosity, and susceptibility to oxidation. It mainly consists of the following systems:
Pay-off System
Core Equipment: Pay-off stand.
Function: Supports and releases the bare steel wire rope from the carrier reel.
Key Requirement: Provides stable and adjustable pay-off tension to ensure the wire rope enters the head straight.
Pre-treatment System
Core Equipment: Cleaning device, Pre-heater.
Function:
Cleaning: Thoroughly removes oil and impurities from the steel wire rope surface.
Pre-heating: Precise pre-heating (temperature typically 150-220°C) is crucial. It enhances bonding strength and reduces the temperature difference with the high-temperature nylon melt, preventing overly rapid crystallization.
Special Requirement: Nylon is highly hygroscopic; the production environment must be kept dry.
Extrusion System
Core Equipment: High-performance extruder, Nylon-specific screw, Dehumidifying drying feed system, Precision die (Head).
Function: Melts, plasticizes dried nylon pellets, and extrudes them uniformly to coat the steel wire rope surface.
Drying System: This is the primary prerequisite for nylon extrusion. Must be equipped with an efficient dehumidifying dryer to ensure the nylon raw material has very low moisture content (typically required <0.02%) before entering the extruder. Otherwise, it can cause bubbles, silver streaks, and severe strength reduction in the product.
Extruder: Requires high temperature control accuracy and sufficient heating power. The screw is typically a sudden compression type with an efficient check ring to prevent nylon melt backflow. The feed section needs forced cooling to prevent premature softening and clumping of nylon pellets.
Head (Die): The flow channel design must be smooth, without dead zones, to prevent nylon stagnation and decomposition. Due to the low viscosity of the nylon melt, the mold sealing requirements are extremely high to prevent leakage.
Cooling and Setting System
Core Equipment: Cooling water tank.
Function: Cools and solidifies the high-temperature nylon coating layer.
Process: Nylon is a crystalline polymer. The cooling rate directly affects its crystallinity, which in turn affects the product's dimensional stability and mechanical properties. Gentle and controlled cooling is usually required, sometimes even initial slow cooling in a hot water bath is needed to control the crystallization process.
Pulling System
Core Equipment: Puller (high-precision dual-caterpillar type).
Function: Provides smooth, slip-free pulling force.
Key Requirement: Speed must be strictly synchronized with the extrusion speed to ensure uniform coating thickness.
Take-up System
Core Equipment: Take-up stand.
Function: Winds the finished product neatly.
Type: Active take-up, equipped with traverser and constant tension control.
Electrical Control System
Core Equipment: High-performance PLC, Touchscreen (HMI), High-precision temperature control modules.
Function: Achieves precise control over the entire line, especially the temperatures of each extruder zone and the dew point of the drying system.

Nylon-Coated Steel Wire Rope Extrusion Line Datasheet

Model	30	40	50	60	70	80	90
Screw Diameter (mm)	φ30	φ40	φ50	φ60	φ70	φ80	φ90
Screw L/D Ratio	25:1	25:1	26:1	26:1	26:1	26:1	26:1
Extrusion Amount (kg/hr)	25	40	70	100	140	200	250
Outlet Wire (mm)	0.2-1	0.4-3	0.8-5	1-8	2-15	3-25	5-35
Total Power (KW)	18	20	25	33	40	55	63
Traction Power (KW)	2.2	2.2	4	4	4	5.5	5.5
Production Speed (m/min (Max.))	600	600	600	500	500	300	300
Take-up Spool (mm)	φ200-400	φ300-500	φ400-630	φ400-630	φ500-630	φ800-1000	φ1000-1250

Nylon-Coated Steel Wire Rope Extrusion Line Application

The Nylon-coated steel wire rope extrusion production line is a production line with relatively high technical barriers. The key to its successful operation lies in the strict control of raw material deep drying, precise temperature control, and crystallization process management. Its resulting nylon-coated steel wire ropes perfectly combine the strength of steel wire rope with the comprehensive mechanical properties of nylon, making them particularly suitable for heavy industry, high-end transmission, and special fields with comprehensive requirements for strength, wear resistance, and temperature resistance. Specific applications are as follows:
Industrial Machinery and Transmission
High-strength, wear-resistant transmission ropes/belts: Used as synchronous belt/rope cores for mining machinery and heavy conveying equipment, bearing high loads and offering wear resistance.
Elevator compensation ropes/chains: High strength, smooth operation, low noise.
Industrial robot internal drive ropes: Meet the transmission needs for high precision and high repeatability.
Automotive and Transportation
Automotive control cables: Such as throttle and brake cables, with low friction and durability.
Vehicle control cables: Used as protective sheathing and core shafts for various control mechanisms.
Sports, Leisure, and Outdoor
Climbing ropes, safety ropes (as internal core or primary coating): High strength, abrasion resistant.
Sailboat rigging, fishing lines (heavy duty): High strength and weather resistance.
Transmission and suspension systems for outdoor sports equipment.
Special Fields
Military and security equipment: Used for lifting and lowering systems requiring high strength and concealment.
Conveyor belt skeleton in high-temperature environments.
Traction ropes for heavy-duty, wear-resistant, and oil-resistant applications in oil fields and mines.