With the rapid development of industrial automation, robotics, CNC machinery, new energy systems, and medical equipment, flexible cable has become a critical component in dynamic applications due to its excellent bending resistance, fatigue resistance, and high reliability. However, in practical use, failures such as conductor breakage, jacket cracking, and signal degradation still occur frequently, significantly affecting equipment stability and service life.
Common Causes of Flexible Cable Failure
Conductor Fatigue Caused by Repeated Bending
In dynamic applications such as drag chains and robotic joints, flexible cable is subjected to high-frequency reciprocating bending. If the conductor structure is not properly designed, metal fatigue can easily occur.
Main contributing factors include:
Use of solid conductors or low-strand-count conductors
Insufficient fatigue resistance of conductor materials
Bending radius smaller than the cable's rated minimum
Typical symptom:
The cable jacket appears intact, while internal conductors have already fractured.
Improper Jacket Material Leading to Aging or Cracking
The jacket is the first line of protection for a flexible cable, and its material properties directly affect cable lifespan.
Common issues include:
PVC jackets becoming brittle in low-temperature environments
Standard rubber materials lacking oil or chemical resistance
Long-term UV exposure causing material degradation
Once the jacket fails, the conductors are highly vulnerable to mechanical damage and environmental intrusion.
Tensile Stress and Improper Installation
During installation, axial tensile forces on flexible cable can cause conductor elongation and shielding damage.
Typical installation errors include:
Excessive filling ratio in drag chains
Improper cable fixing points
Lack of strain relief mechanisms
Long-term tensile stress accelerates internal structural damage and significantly shortens service life.
Electromagnetic Interference and Shielding Failure
In servo systems, frequency converters, and data communication applications, insufficient shielding design in flexible cable can result in signal instability.
Failure causes include:
Low shielding coverage
Shield layers not bending synchronously with conductors
Improper grounding methods
These issues may lead to communication errors, unstable signals, or even system malfunctions.
Environmental Factors Causing Comprehensive Failure
Special environments place higher demands on flexible cable, such as:
High temperatures softening insulation materials
Chemical exposure degrading material structures
High humidity reducing insulation performance
If environmental conditions are not fully considered during product selection, failure becomes inevitable.
Preventive Measures for Flexible Cable Failure
Optimized Conductor Structure Design
High-quality flexible cable typically adopts:
High-strand-count ultra-fine stranded copper conductors
Multi-layer, reverse-twist stranding structures
High-purity oxygen-free copper
These designs significantly improve bending fatigue resistance.
Proper Selection of Jacket and Insulation Materials
Different applications require different material combinations:
Drag chain applications: PUR / TPE
Low-temperature environments: TPE or special elastomers
Oil and chemical resistance: PUR
Outdoor applications: UV-resistant modified materials
Material selection is critical to extending flexible cable service life.
Compliance with Correct Installation Practices
Recommended preventive measures include:
Ensuring the bending radius meets or exceeds the rated minimum
Keeping drag chain filling ratios below 60%
Using proper fixing clamps and strain relief devices
Avoiding cable twisting and cross-laying
Proper installation alone can reduce early failure rates by more than 50%.
Enhanced Shielding and Grounding Design
For signal-type flexible cable, it is recommended to:
Use high-coverage braided shielding
Ensure synchronous twisting of shield and conductors
Apply 360° grounding methods
These measures effectively reduce EMI and improve system stability.
Typical Application Scenarios of Flexible Cable
Energy Chain (Drag Chain) Systems
CNC machine tools
Automated production lines
Logistics and sorting equipment
Characteristics: high-frequency reciprocating motion and long service life requirements.
Industrial Robots and Robotic Arms
Six-axis robots
Collaborative robots
Welding and material handling systems
Key requirements: extremely high flexibility and torsion resistance.
Servo and Motion Control Systems
Servo motor cables
Encoder cables
Feedback and control signal cables
Focus: stable electrical performance and strong anti-interference capability.
New Energy and Specialized Equipment
Wind power and solar tracking systems
Medical devices
Semiconductor manufacturing equipment
Emphasis on environmental adaptability and high reliability.
How to Select the Right Flexible Cable
Define the Motion Type
Fixed installation
Reciprocating motion in drag chains
Torsional motion
Different motion types require different structural designs.
Determine Environmental and Lifetime Requirements
Key considerations include:
Temperature range
Chemical exposure
Required bending cycles (millions or tens of millions)
Avoid using "general-purpose cables" in high-demand dynamic applications.
Focus on Critical Technical Parameters
During selection, carefully verify:
Minimum bending radius
Bending cycle life rating
Shielding structure
Certifications (UL, CE, RoHS)
Choose an Experienced Supplier
Reliable flexible cable manufacturers typically offer:
Clear application-specific product classifications
Verified lifetime test data
Technical support and selection assistance
These factors are often more important than price alone.
Flexible cable failure is not inevitable-it is usually the result of improper design, selection, or application.
By understanding failure mechanisms, applying targeted preventive measures, and selecting products based on real application conditions, system reliability can be significantly improved while maintenance costs are reduced.
In increasingly automated and intelligent industrial environments, flexible cable will continue to play a critical role, with growing trends toward specialization, customization, and high reliability.
At Dongguan Greater Wire & Cable Co., Ltd., we understand that choosing the right wire and cable solutions is critical to the success and safety of your projects.
Our experienced pre-sales and after-sales teams provide:
Professional technical consultation
Accurate product selection and application guidance
Fast and responsive support throughout the entire project lifecycle
Whether you are working on small-scale installations or large industrial projects, we are committed to delivering reliable solutions and practical support tailored to your specific requirements.
Contact Us
Dongguan Greater Wire & Cable Co., Ltd.
📞 Tel / WhatsApp / WeChat
+86 135 1078 4550
+86 136 6257 9592
📧 Email
manager01@greaterwire.com
We look forward to supporting your next project with quality products, technical expertise, and dependable service.