Robot Drag Chain Cable Extrusion Line

Robot Drag Chain Cable Extrusion Line

Robot drag chain cables are a type of specialized, highly flexible cable specifically designed for high-speed, long-distance reciprocating motion within drag chain systems. They act as the "dynamic lifeline" between the robot and external equipment (such as control cabinets, seventh-axis ground rails), primarily responsible for transmitting power, control signals, data, and even fiber optics. Unlike "body cables" installed inside the robot arm, drag chain cables are typically located externally on the robot, housed within a plastic or metal conduit called a "drag chain" or "energy chain" to guide and protect the cable.

Core Characteristics

The core design goals of drag chain cables are to meet the unique stresses generated during high-speed movement inside the drag chain:
Extremely High Bend Resistance
This is the most critical requirement. The cable must withstand continuous, small-radius (typically 7.5 times the cable's outer diameter or less) bending cycles imposed by the drag chain. The service life of high-quality drag chain cables needs to reach millions of cycles (e.g., 5 million to 10 million cycles or more).
Exceptional Abrasion Resistance
Movement inside the drag chain causes continuous friction against the chain links' inner walls and other cables. Therefore, its outer sheath must be made of extremely wear-resistant material (such as polyurethane PUR) to prevent wear and damage.
Good Tensile Strength
Due to the cable's own weight and motion inertia, especially in long-stroke applications, the cable needs to withstand certain tensile forces. A tensile element (such as aramid yarn or fiber rope) is usually integrated internally to prevent the cable from stretching or being damaged during movement.
Temperature and Environmental Resistance
Must withstand oil, coolant, chemicals, and a certain temperature range (e.g., -30°C to +90°C) found in industrial environments. The sheath material needs corresponding oil resistance and flame retardancy.
Anti-Interference Capability
Power and signal cables are often integrated within the same cable (hybrid cable), necessitating high-quality shielding (such as tinned copper braided shielding) to ensure signal transmission is free from electromagnetic interference.
Flexibility and Small Outer Diameter
To bend easily within the drag chain and save space, the cable needs to be very flexible, with an outer diameter typically designed as small as possible and a compact structure.

Common Structure

To meet the above requirements, its typical structure is as follows:
Conductor: Uses extra-fine oxygen-free copper wires (Class 6/7 conductors), finely stranded to ensure basic flexibility.
Insulation: Uses specially formulated thermoplastic elastomers (TPE) or polyurethane (PUR) to provide elastic insulation protection.
Cabling: Cores are stranded together with an optimized lay length, often stranded around a central tensile element (aramid yarn) to distribute stress evenly.
Inner Sheath: Holds the cable core tightly together, forming a round, integrated whole to reduce internal friction.
Shielding: High-coverage (typically ≥85%) tinned copper braided shielding provides excellent electromagnetic shielding and mechanical fatigue resistance.
Outer Sheath: Uses high-strength, highly abrasion-resistant polyurethane (PUR) material as the outermost protection, commonly in black, orange, or grey.

Robot Drag Chain Cable Extrusion Line

The robot drag chain cable extrusion production line is a complete set of equipment specifically used for manufacturing highly flexible drag chain cables. These cables are primarily used in applications requiring high-speed, long-stroke reciprocating motion, such as robot seventh axes (ground rails) and moving units of automated equipment. Unlike body cable production lines that emphasize "torsion resistance," the technical core of the drag chain cable production line lies in achieving ultimate cable flexing endurance, wear resistance, and tensile strength. Its production philosophy is "softness overcomes hardness," ensuring through precise processes that the cable maintains structural integrity and stable performance after millions of bending cycles within the drag chain.

Core Components

The core components of a professional drag chain cable extrusion production line are similar to those of a body cable line, but the process focus differs:
High-Stability Pay-Off System
Function: Smoothly releases the conductor or cable core.
Key Requirement: Constant tension control. Prevents internal cable structure loosening due to uneven tension during pay-off, which affects bending lifespan.
Conductor Preheating System
Function: Preheats the conductor, removing moisture.
Importance: Enhances material adhesion, reduces internal stress between the insulation layer and the conductor, and is key to preventing wrinkling or delamination of the cable under repeated bending.
Core Extrusion System
a. Extruder: Uses a screw suitable for flexible materials (e.g., PUR, PVC, TPE) to ensure uniform plasticization and avoid material degradation.
b. Head and Die: Must use a crosshead to ensure the concentricity of the extruded layers. Any eccentricity creates additional stress during bending, leading to premature cable failure.
Efficient Cooling System
Function: Rapidly solidifies and sets the molten sheath and insulation layers.
Characteristics: Unlike the "slow cooling" for body cables, drag chain cables typically require a long water tank with multi-stage cooling. However, water temperature control remains crucial to ensure sufficient and uniform cooling for obtaining good mechanical properties.
Online Detection System
Diameter/Eccentricity Gauge: Monitors in real-time to ensure quality consistency.
Spark Tester: 100% inspection of the insulation layer's integrity.
Track-Type Haul-Off / Puller
Function: Provides stable and powerful pulling force.
Characteristics: Uses a track-type puller with a large contact area and even pressure distribution, avoiding indentation or damage to the soft cable core.
Constant Tension Take-Up System
Function: Neatly winds the finished cable onto large reels.
Requirement: Take-up tension must be constant and gentle to prevent over-stretching of the cable.
Central Control System
Function: Integrated control to achieve automated operation of the entire line and traceability of process parameters.

Robot Drag Chain Cable Extrusion Line Datasheet

Model	30	40	50	60	70	80	90	100	120	150
Screw Diameter (mm)	φ30	φ40	φ50	φ60	φ70	φ80	φ90	φ100	φ120	φ150
Screw L/D Ratio	25:1	25:1	26:1	26:1	26:1	26:1	26:1	25:1	25:1	25:1
Extrusion Amount (kg/hr)	25	40	70	100	140	200	250	320	450	650
Outlet Wire (mm)	0.2-1	0.4-3	0.8-5	1-8	2-15	3-25	5-35	8-60	10-80	15-120
Total Power (KW)	18	20	25	33	40	55	63	120	165	220
Traction Power (KW)	2.2	2.2	4	4	4	5.5	5.5	11	11	15
Production Speed (m/min (Max.))	600	600	600	500	500	300	300	100	80	60
Take-up Spool (mm)	φ200-400	φ300-500	φ400-630	φ400-630	φ500-630	φ800-1000	φ800-1250	φ1000-2000	φ2000-2500	φ2500-3150

Robot Drag Chain Cable Extrusion Line Application

The robot drag chain cable extrusion production line is key equipment for manufacturing the "dynamic lifeline" in automation. Its technical core lies in producing cables capable of withstanding harsh bending stresses through high concentricity extrusion, uniform cooling, and stable tension control, meeting the extreme demands for reliability and durability in modern high-tempo automated production.
The drag chain cables manufactured by this production line are mainly used in the following scenarios, categorized by application:
Robot Seventh Axis (Ground Rail) Cables
Description: Used for power supply and signal transmission driving the entire robot's movement on the track.
Requirements: Typically require longer lengths, possessing excellent tensile strength, bend resistance, and torsion resistance (generated at track turns).
Automation Equipment Moving End Cables
Description: Used for moving parts that travel within drag chains on equipment such as CNC machine tool magazines, machining centers, gantries, and logistics sorting lines.
Requirements: Select cables with different protection grades based on equipment speed, travel distance, and environment (e.g., presence of oil, coolant).
Robot External Wiring Cables
Description: Cables that guide power and signals from the fixed control cabinet to the robot base or moving arm.
Requirements: Often need to integrate multiple functions (power, feedback, data, etc.), i.e., hybrid cables.
Categorized by Cable Structure
Single-Core Shielded Cables
Used for transmitting a single type of signal, such as encoder or sensor signals, requiring high anti-interference capability.
Multi-Core Power and Control Cables
Integrate multiple power and control lines into one cable to power actuators and transmit control signals.
Hybrid Drag Chain Cables
This is the highest-end application. Integrates power, control, data, and even fiber optics and air lines into a single cable.
Advantages: Simplifies equipment wiring, reduces the weight and space occupied by moving parts, and facilitates installation and maintenance.
Manufacturing Difficulty: Requires extremely high precision from the production line to ensure stable structure of cores made from different materials after cabling and sheath extrusion, preventing mutual interference and wear during bending.