XLPE/PVC Insulated Aluminum/Copper Power Cables for Underground (50mm² , 70mm² , 150mm²)

XLPE Insulation: It has a high temperature resistance level, with a long-term operating temperature of up to 90°C and a maximum short-circuit temperature of 250°C. The insulation resistance is extremely high, usually above 1000MΩ, and the dielectric loss tangent is small, generally less than 0.002 at power frequency, featuring excellent electrical performance.

PVC Insulation: The long-term operating temperature is generally 70°C, and the maximum short-circuit temperature is 160°C. The insulation resistance is relatively lower than that of XLPE but can still meet the requirements of low-voltage distribution. The dielectric loss tangent is slightly higher than that of XLPE, approximately 0.01-0.03 at power frequency.

Copper Core Conductor: It has high purity, generally with a copper content of over 99.9%, high conductivity of about 58MS/m, and low DC resistance. At 20°C, the DC resistance of a 50mm² copper core conductor is not more than 0.383Ω/km, 70mm² not more than 0.268Ω/km, and 150mm² not more than 0.124Ω/km.

Aluminum Core Conductor: It also has high purity, usually with an aluminum content of over 99.5%, and a conductivity of about 37MS/m. The DC resistance is relatively larger than that of the copper core. At 20°C, the DC resistance of a 50mm² aluminum core conductor is not more than 0.595Ω/km, 70mm² not more than 0.408Ω/km, and 150mm² not more than 0.193Ω/km.

XLPE (Cross-Linked Polyethylene): It is a polyethylene material processed by cross-linking, with a three-dimensional network structure, which endows it with excellent high-temperature resistance, aging resistance, and mechanical strength. This material is non-toxic, odorless, has good chemical stability, is not easily corroded by acids and alkalis, and can maintain good insulation performance in harsh underground environments for a long time.

PVC (Polyvinyl Chloride): It is a common polymer material with good plasticity and processability, and relatively low price. It has high mechanical strength, good impact resistance, and certain chemical corrosion resistance. However, it is prone to decomposing and producing harmful gases at high temperatures, so its temperature resistance level is relatively low.

Copper Core: Copper is a high-quality conductive material with good electrical conductivity, thermal conductivity, and ductility. The surface of the copper core is not easy to oxidize, has low contact resistance, and a long service life, which is suitable for scenarios with high requirements for transmission performance. However, copper resources are relatively scarce and the price is high.

Aluminum Core: Although the conductivity of aluminum is not as good as that of copper, its resources are abundant and the price is low. The aluminum core is lightweight, convenient for transportation and laying, but its surface is prone to oxidation to form an oxide film, which affects the conductive performance, so special treatment is required during connection.

Copper Core Manufacturing: First, copper ingots are smelted to remove impurities and then cast into copper rods. The copper rods are drawn into Copper Wires of different diameters through a wire drawing machine. During the wire drawing process, annealing treatment is required to improve the Flexibility and conductivity of the copper wires. Then, multiple copper wires are twisted together according to certain rules to form a copper core conductor with the required cross-sectional area. During the twisting process, the roundness and tightness of the conductor must be ensured.

Aluminum Core Manufacturing: Aluminum ingots are smelted, purified, and then cast into aluminum rods. The aluminum rods are drawn into Aluminum Wires through a wire drawing machine, which also requires annealing treatment. Due to the relatively poor toughness of aluminum, the process parameters must be controlled during wire drawing and twisting to avoid Aluminum Wire breakage. Multiple aluminum wires are twisted to form an aluminum core conductor, and the twisted conductor needs surface treatment to prevent oxidation.

XLPE Insulation Extrusion: The cross-linking extrusion process is adopted. XLPE materials are added to the extruder, melted and plasticized under high temperature and pressure, and extruded and wrapped on the surface of the conductor through a mold to form an insulation layer. After extrusion, cross-linking treatment is required. Common cross-linking methods include warm water cross-linking, steam cross-linking, and irradiation cross-linking, so that XLPE molecules form a three-dimensional network structure to obtain excellent performance.

PVC Insulation Extrusion: PVC resin is mixed with plasticizers, stabilizers and other additives uniformly and then added to the extruder. After heating and melting, it is extruded and wrapped on the surface of the conductor through a mold. During the extrusion process, parameters such as temperature and speed must be controlled to ensure that the insulation layer has uniform thickness, smooth surface, and is closely combined with the conductor.

Road Transportation: Suitable for medium and short-distance transportation, with high flexibility, and can directly deliver the cable to the destination. The transport vehicles usually choose large trucks, and the carriage is equipped with fixing devices to fix the cable reels firmly to prevent shaking and collision during transportation.

Railway Transportation: Suitable for long-distance and large-volume transportation, with relatively low transportation cost and good stability. Cable reels are transported by railway freight cars, which must be loaded and fixed in accordance with the regulations of the railway department to ensure transportation safety.

Water Transportation: Suitable for cross-regional or transnational transportation, with large transportation volume and low cost. When loading cable reels on board, attention should be paid to reasonable stacking to avoid compression deformation, and moisture-proof and anti-corrosion measures should be taken at the same time.

Order Confirmation: After receiving the customer's order, the sales staff will verify the product model, specification, quantity, delivery date, delivery location and other information with the customer to ensure accuracy.

Inventory Check: Warehouse managers check the inventory according to the order information. If the inventory is sufficient, they will arrange for goods preparation in a timely manner; if the inventory is insufficient, they will notify the production department to organize production to ensure on-time delivery.

Product Inspection: After goods preparation is completed, quality inspectors re-inspect the cables to confirm that the product quality is qualified before delivery.

Arrange Transportation: Choose an appropriate transportation method according to customer needs and actual conditions, and sign a transportation contract with the transportation company to clarify the responsibilities and obligations of both parties.

Delivery Notification: After the cable is shipped, timely notify the customer of the transportation method, license plate number, ship number, estimated arrival time and other information to facilitate the customer to prepare for receipt.