An excessively small bending radius in power cords can have multi-dimensional negative impacts on their long-term performance. This impact stems from the combined effects of physical structural damage and material degradation. When a power cord is excessively bent, the internal conductor, insulation layer, shielding layer, and outer sheath will all experience stresses exceeding their design limits, triggering a series of chain reactions.
The conductor, as the core component for current transmission, directly determines its conductivity based on its structural stability. Power cord conductors are typically composed of multiple strands of fine copper wires. This design is intended to enhance flexibility, but when the bending radius is too small, the stranding structure between the copper wires is disrupted, leading to breakage or loosening of some wires. Broken copper wires create localized resistance spikes, causing not only power loss but also accelerated insulation aging due to heat generation. In the long term, this damage will gradually expand, eventually leading to poor contact, voltage fluctuations, and even short-circuit faults, severely affecting the normal operation of the equipment.
The insulation layer is a critical barrier ensuring the safety of the power cord; its performance degradation directly threatens operational safety. Under excessive bending conditions, the insulation material will develop microscopic cracks due to tension or compression. These cracks become channels for the penetration of contaminants such as moisture and dust. Over time, insulation resistance gradually decreases, significantly increasing the risk of leakage. Especially in humid environments, moisture intrusion can trigger electrochemical corrosion between the insulation layer and the conductor, further weakening insulation performance. Furthermore, localized overheating accelerates the aging process of the insulation material, making it brittle, cracking, and ultimately losing its protective function.
For power cords equipped with shielding layers, excessive bending can also damage the electromagnetic shielding system. The shielding layer, typically composed of metal braided mesh or aluminum foil, is designed to suppress external electromagnetic interference and prevent signal leakage. When the bending radius is too small, the shielding layer will deform, creating gaps or wrinkles, leading to a significant decrease in shielding effectiveness. This not only makes the signals transmitted by the power cord susceptible to external interference but may also cause excessive electromagnetic radiation, affecting surrounding electronic equipment. This effect is particularly pronounced in high-frequency signal transmission scenarios, potentially manifesting as data transmission errors, communication interruptions, and other malfunctions.
The outer sheath, as the first line of defense for the power cord, is crucial to its overall lifespan. Excessive bending can cause cracks or peeling on the surface of the outer sheath, rendering it ineffective in protecting the internal structure. Once the outer sheath is damaged, the internal conductors, insulation, and shielding layers are directly exposed to harsh environments, accelerating the aging process. Furthermore, damage to the outer sheath can also trigger mechanical protection failure, making the power cord more susceptible to breakage under impact, further shortening its lifespan.
Prolonged excessive bending can also cause fatigue damage. During repeated bending, microscopic damage accumulates within the power cord material. This damage gradually builds up and expands, eventually leading to a permanent decline in material performance. For example, conductors may fracture due to fatigue, insulation may crack due to fatigue, and shielding may deform due to fatigue. This fatigue damage is insidious and difficult to detect initially, but in the long run, it significantly reduces the reliability and safety of the power cord.
An excessively small bending radius in the power cord also affects its ease of installation and maintenance. Excessively bent power cords become stiff and difficult to manage, increasing wiring difficulty and potentially causing localized deformation due to stress concentration. This deformation further exacerbates internal structural damage, creating a vicious cycle. Moreover, when replacement or repair is needed, excessively bent power cords may be difficult to disassemble or reconnect, increasing maintenance costs and time.
