The commonly used cabo de rede industrial outer sheath is divided into two types: PUR network cable e PVC network cable. In some specific environments, PUR network cable must be used.
Polyurethane (PUR) shielded network cables, as a high-performance communication cable, have shown significant advantages in industrial automation, data centers, medical equipment, and network cabling in harsh environments in recent years. Its unique material properties and structural design make it far superior to ordinary network cables in terms of anti-interference, weather resistance, and mechanical strength, making it the preferred solution for special application scenarios.
1.Material characteristics of Cabo Ethernet PUR: chemical advantages of polyurethane
Polyurethane materials possess multiple properties due to the amino ester groups (- NHCOO -) in their molecular structure. In PUR shielded Ethernet cable, the outer sheath is made of thermoplastic polyurethane (TPU), which has an adjustable hardness range (usually Shore A 70-95) and combines the elasticity of rubber with the strength of plastic. Compared to traditional PVC sheaths, PUR outer sheaths have a tensile strength of 35-50MPa and an elongation at break of over 400%, maintaining flexibility even at extreme temperatures ranging from -40 ℃ to 90 ℃. This characteristic allows it to bend and route normally in low-temperature environments such as oil drilling platforms and polar scientific research stations.
Chemical stability is another core advantage. Polyurethane has a much higher tolerance to mineral oil, fuel oil, and most solvents than PVC. Experimental data shows that its volume expansion rate after soaking in diesel for 72 hours is less than 3%, while PVC can reach over 15%. This extends the lifespan of PUR network cables by 3-5 times in scenarios where there is a risk of oil pollution and corrosion, such as chemical plants and automobile manufacturing. A test report from a Chinese automation equipment manufacturer shows that the PUR CAT6A Ethernet cable used in their workshop’s robotic arm has not experienced sheath cracking for 36 months in continuous contact with cutting fluid.
2. Shielding structure of PUR network cable: multi-layer defense system
The standard PUR shielded Ethernet cable adopts a composite shielding scheme: each pair of twisted pair cables is wrapped with aluminum foil Mylar tape (thickness ≥ 0.025mm) to achieve individual shielding, and then wrapped with tin plated copper wire braided mesh (coverage ≥ 85%) to form the total shielding layer. This design can attenuate electromagnetic interference (EMI) to over 60dB, far exceeding the 30dB of unshielded network cables. In a comparative test at a medical imaging center in Shanghai, when the MRI equipment was working, the error rate of ordinary PUR CAT5e cable reached 10 ⁻⁵, while PUR shielded network cable remained below 10⁻⁸.
In special scenarios, PUR drag chain Ethernet cable will also use double-layer braided shielding. For example, in the aerospace field, Cabo PUR will add a nickel copper alloy secondary braided layer to increase shielding effectiveness to 90dB. It is worth noting that the bonding process between the shielding layer and the PUR sheath is crucial. High quality products will use extrusion wrapping technology to ensure that the gap between the sheath and the shielding layer is less than 0.1mm, avoiding secondary radiation caused by the “antenna effect”.
3.Mechanical performance and durability testing of PUR industrial Ethernet cable
Cabos Ethernet PUR have passed three key tests for mechanical stress in industrial scenarios:
● Reciprocal bending test: Under the condition of a radius of 5D (where D is the wire diameter), after 5000 bending cycles, the change in transmission loss should be less than 3%. According to the actual test data of a German brand, its high flexibility PUR network cable still maintains the ISO/IEC 11801-1 Class EA standard after 10000 tests.
● The anti rolling test of PUR network cable: After withstanding a pressure of 100kg/cm ², the insulation resistance is greater than 500M Ω. This is closely related to the nano silica filler added to the sheath, and its Mohs hardness can reach level 7.
● UV aging test of PUR Ethernet cable: After simulating 3 years of outdoor exposure in QUV accelerated aging equipment, the retention rate of tensile strength needs to be greater than 80%. The performance of PUR sheath with added carbon black stabilizer is 40% better than that of ordinary formula.
4.Application scenarios of flexible PUR network cable
In the field of intelligent manufacturing, the application of flexible PUR Ethernet cable drag chains has become a highlight. A case study from a certain automobile welding workshop shows that in a drag chain with an acceleration of 2m/s ² and a stroke of 5 meters, the average lifespan of ordinary network cables is only one month, while the attenuation of PUR drag chain ethernet cable is still controlled within 3dB/100m after 24 months of operation. This is due to three improvements:
● The conductor is made of twisted copper with anti bending properties (single wire diameter 0.08mm)
● Change the filling material to aramid fiber reinforced core
● The insulation is made of modified PE, which is resistant to bending
Medical grade PUR Ethernet cables have passed biocompatibility certification (ISO 10993-5), with a flame retardant rating of IEC 60332-1-2 standard and a smoke density of less than 15% during combustion (FT4 test). In the application of surgical robots, this cable can withstand high temperature steam sterilization at 134 ℃, with a cycle of over 500 times.
5.PUR Ethernet Cable Selection Guide
● Core count/specification: commonly used 8-core Cat5e 4x2x0.14 (26awg); Choose Cat6a for gigabit.
● Shielding: Choose dual shielding (S/FTP) for strong interference environments; Optional unshielded (UTP) for regular environments.
● Bending radius: Drag Chain High Flexion Ethernet cable is selected according to the inner diameter of the drag chain to avoid fatigue fracture caused by being too small.
● Temperature/Environment: Oil stains/PUR must be selected for outdoor use; Low temperature (below -20 ℃) preference for polyether PUR.
With the advancement of Industry 4.0, the annual growth rate of the global PUR shielded Ethernet cable market remains stable at 8.7% (Grand View Research data), and the market share in China is expected to increase from $320 million in 2025 to $480 million in 2030. Driven by demanding communication requirements in harsh environments, this highly flexible PUR network cable is redefining the standard for reliable transmission.