PVC Insulated/Sheathed 4c× 185mm² Underground Copper Power Cable

The cable adopts a 4-core Copper Conductor design, with each core having a cross-sectional area of 185mm² and a diameter of approximately 15.2mm. The conductors are made of high-purity electrolytic copper with a purity of over 99.95%, which endows it with excellent conductivity, maintaining a stable conductivity of over 58MS/m. At an ambient temperature of 20℃, the DC resistance of the conductor per kilometer does not exceed 0.103Ω, effectively reducing losses during current transmission. The conductor is manufactured using a multi-strand stranding process, with each strand of Copper Wire having a diameter of 0.2mm-0.3mm. The stranding pitch is controlled within 16-20 times the conductor diameter, ensuring both the Flexibility of the conductor and enhancing its mechanical strength, with a maximum tensile force of 12kN.

The insulation layer is made of weather-resistant PVC material, with a uniform thickness strictly controlled between 1.8mm-2.2mm, and the thickness deviation on the same cross-section does not exceed 0.2mm. The insulation resistance of the insulation layer at 20℃ is not less than 1000MΩ·km, and the breakdown strength is ≥10kV/mm. It can withstand a 1kV AC voltage withstand test for 1min without breakdown. The volume resistivity of the Insulation Material is ≥1×10¹⁴Ω·cm, and the dielectric loss tangent at 50Hz is ≤0.03, ensuring good electrical insulation performance. In addition, the insulation layer has certain temperature resistance, maintaining stable performance at a long-term working temperature of 70℃ without softening or cracking.

The outer sheath is made of thickened PVC material, with a thickness of 2.0mm-2.5mm. The average thickness is not less than 90% of the specified value, and the thinnest part is not less than 80% of the specified value. The sheath has a tensile strength of ≥12MPa and an elongation at break of ≥150%, with good mechanical properties, capable of withstanding various external impacts during underground laying. The sheath material has undergone special treatment, with excellent acid and alkali resistance. After being immersed in 10% concentration hydrochloric acid, sulfuric acid, and sodium hydroxide solutions for 72h, the change rates of its tensile strength and elongation at break do not exceed 20%. At the same time, the oxygen index of the sheath is ≥30, with good flame retardancy, meeting the Class B flame retardant requirements in GB/T 18380.1-2002.

The rated voltage of the cable is 0.6/1kV, where 0.6kV is the phase voltage and 1kV is the line voltage, suitable for low-voltage power distribution systems. The long-term working temperature range of the cable is -15℃ to 70℃. At -15℃, the cable has good bending performance without cracks; at 70℃, the performance of the insulation and sheath materials remains stable. In case of a short circuit (with a duration not exceeding 5s), the cable can withstand a high temperature of 160℃ without affecting its subsequent performance. The overall outer diameter of the cable is approximately 25mm, and the 4-core bundled structure is compact, with a bending radius of not less than 12 times the cable outer diameter (about 300mm), facilitating laying in narrow underground spaces. The weight of the cable per kilometer is approximately 850kg-900kg, with the conductor weight accounting for about 60% and the insulation and sheath weight accounting for about 40%.

In urban power grid transformation projects, this cable can be used as an underground main line to connect substations and various distribution rooms, undertaking the important task of power transmission in the region. With the continuous growth of urban electricity load, the requirements for the stability and reliability of power transmission are increasing. The 4-core design of this cable can meet the needs of a three-phase four-wire power distribution system, and the 185mm² cross-sectional area can ensure a large current-carrying capacity. Under the conditions of an ambient temperature of 30℃ and direct burial laying, the current-carrying capacity can reach 320A, meeting the electricity needs of urban residents and commercial users. At the same time, its excellent environmental resistance can adapt to complex underground soil conditions and various corrosive factors in cities, ensuring the safe and stable operation of the power grid.

Industrial parks gather a large number of industrial enterprises, with many high-power electrical equipment, requiring high standards for Power Cables. This cable can be used to connect the factory's main distribution station with various production workshops, providing stable power for large motors, production lines, CNC machine tools and other equipment. Industrial environments often have oil stains, dust, chemical substances, etc. The PVC Sheath of this cable has good oil resistance and chemical corrosion resistance, which can effectively resist the erosion of these factors. In addition, its flame retardancy can also reduce the risk of fires caused by electrical faults in industrial parks, ensuring the normal operation of industrial production.

In the construction of residential communities, this cable can be used as an incoming line cable, accessing the community distribution center from the municipal power grid and then distributing to each building. The underground environment of residential communities is relatively complex, with possible humidity and water accumulation. The PVC Insulation and sheath of this cable have good moisture resistance, which can effectively prevent moisture from entering the cable and ensure the normal transmission of electricity. At the same time, its 4-core design simplifies the wiring of the community power distribution system, reduces the number of cables laid, and lowers construction costs and difficulties. For some high-end residential communities with higher requirements for the reliability of power supply, the stable performance of this cable can meet their needs and reduce the occurrence of power outages and other faults.

In municipal engineering projects such as road lighting, underground parking lots, and sewage treatment plants, this cable is also widely used. The Underground Cables of road lighting systems need to withstand external forces such as vehicle rolling, and the thickened sheath and high-strength conductor of this cable can meet this requirement; the environment of underground parking lots is relatively humid, so the moisture resistance of the cable is crucial; the environment of sewage treatment plants contains a large number of corrosive substances, and the acid and alkali resistance of this cable can ensure its long-term stable operation.

The conductor is made of high-purity electrolytic copper, which has extremely high conductivity and good ductility. Electrolytic copper undergoes an electrolytic refining process to remove impurities, with a purity of over 99.95%, which can effectively reduce resistance loss during current transmission. At the same time, electrolytic copper has good ductility, facilitating wire drawing and stranding processing. The made copper wire has good flexibility and mechanical strength, and can adapt to bending and stretching operations during underground laying.

The insulation layer is made of weather-resistant PVC material. PVC (polyvinyl chloride) is a commonly used polymer insulation material with good electrical insulation performance, mechanical performance, and chemical corrosion resistance. The PVC Insulation Material used in this cable has undergone special formula modification, adding antioxidants, ultraviolet absorbers and other additives to improve its weather resistance and anti-aging performance, enabling it to work stably in underground environments for a long time. Compared with ordinary PVC materials, it has better temperature resistance and will not show performance degradation at a long-term working temperature of 70℃.

The sheath is made of thickened PVC material. On the basis of ordinary PVC materials, plasticizers, stabilizers, flame retardants and other additives are added to further improve its mechanical performance, weather resistance, and flame retardancy. The thickened sheath design enhances the impact resistance and wear resistance of the cable, effectively protecting the internal structure of the cable from external damage in the underground environment. At the same time, the sheath material has good resistance to microbial erosion, preventing the erosion of the cable by bacteria, fungi, etc. in the underground soil.

The cable has an overall circular structure, with 4 Cores symmetrically distributed and tightly stranded together, wrapped with an insulation layer and a sheath layer to form a compact whole. This style design is conducive to reducing resistance during underground laying of the cable, facilitating pipe threading and direct burial operations. The surface of the cable is smooth and flat, without burrs, protrusions and other defects, reducing friction loss during laying. In addition, the color of the cable is usually black, which has good light resistance, can reduce the aging effect of sunlight on the sheath, and is also convenient for distinguishing from other pipelines in the underground environment.

First, high-purity electrolytic copper ingots are made into copper rods through smelting, casting and other processes, with a diameter of approximately 8mm. Then, the copper rods are drawn through a wire drawing machine in multiple passes to make copper wires with a diameter of 0.2mm-0.3mm. During the wire drawing process, the drawing speed and mold size must be strictly controlled to ensure the uniform diameter of the copper wires. Next, multiple copper wires are stranded according to certain stranding rules to form a conductor with a cross-sectional area of 185mm² per core. During stranding, a regular stranding method is adopted, and the stranding directions of adjacent layers are opposite to ensure the roundness and stability of the conductor. During the stranding process, the stranding pitch must be controlled to ensure the flexibility and mechanical strength of the conductor.

After the conductor is stranded, it enters the insulation extrusion process. The weather-resistant PVC insulation material is added to the extruder and melted and plasticized at a temperature of 150℃-180℃. Then, the molten PVC material is uniformly extruded onto the conductor surface through an extrusion die to form an insulation layer. During the extrusion process, the extrusion temperature, speed and pressure must be strictly controlled to ensure that the insulation layer has a uniform thickness, a smooth surface, and is closely combined with the conductor. The extruded cable enters a cooling water tank for cooling, and the cooling water temperature is controlled at 20℃-30℃ to quickly solidify and shape the insulation layer. After cooling, the thickness and appearance of the insulation layer are inspected, and unqualified products are reworked.

The 4 Insulated Conductors enter the cabling machine for cabling operation. During cabling, the 4 Conductors are stranded together according to a certain pitch, and the stranding pitch is usually 10-12 times the cable outer diameter. In the cabling process, to ensure the roundness and stability of the cable, fillers such as polypropylene ropes are filled between the conductors. After cabling, a layer of non-woven tape is wrapped around the cable to play a binding and isolating role, preventing the conductors from rubbing against each other and damaging the insulation layer.

After cabling is completed, the sheath extrusion is carried out. The thickened PVC sheath material is added to the extruder and melted and plasticized at a temperature of 160℃-190℃. The molten PVC material is uniformly extruded onto the surface of the cabled cable through an extrusion die to form a sheath layer. During the extrusion process, the extrusion parameters must be controlled to ensure that the sheath layer has a uniform thickness, a smooth surface, and is closely combined with the internal structure. The extruded cable is cooled in a cooling water tank, and the cooling water temperature is controlled at 20℃-30℃ to solidify and shape the sheath layer. After cooling, the thickness, appearance, and size of the sheath layer are inspected to ensure they meet the requirements.

The finished cable needs to undergo strict finished product inspection. Inspection items include appearance inspection to check whether the surface of the cable has scratches, bubbles, depressions and other defects; size measurement to detect whether the cable outer diameter, insulation thickness, sheath thickness, etc. meet the specification requirements; electrical performance testing such as insulation resistance testing and voltage withstand testing to ensure good electrical performance of the cable; mechanical performance testing such as tensile strength and elongation at break to inspect whether the mechanical strength of the cable meets the standard. In addition, flame retardant performance testing and environmental resistance testing need to be carried out, and only products that pass all testing items can leave the factory.

The cable is packaged with wooden cable reels, which are made of high-quality pine wood, having high strength and toughness, and can bear the weight of the cable and external impacts during transportation. The structure of the cable reel includes a reel shaft, baffles and spokes. The diameter of the reel shaft is 300mm-400mm, the diameter of the baffle is determined according to the length of the cable, usually 1200mm-1500mm, and the spokes are designed with thickening to enhance the stability of the cable reel. The outside of the cable reel is wrapped with a layer of plastic film to prevent the cable from being polluted by dust, moisture, etc. during transportation and storage. At the same time, plastic protective caps are put on both ends of the cable to protect the ends of the cable from damage.

The cable is neatly coiled on the cable reel, and during coiling, the cable must be arranged tightly and neatly to avoid crossing and overlapping. The length of each reel of cable is usually 500m, and can also be customized according to customer requirements. The outside of the cable reel is fixed firmly with steel strips, which have a width of 30mm-50mm and a spacing of 300mm-500mm to prevent the cable from loosening and slipping during transportation. Iron lifting rings are installed on the edge of the cable reel to facilitate the loading, unloading and handling of the cable. A product label is pasted on the side of the cable reel, indicating the product name, model specification, length, weight, production batch number, implementation standard, production date, manufacturer, etc.

The product label is made of wear-resistant materials, printed clearly and firmly, and not easy to fade. The information on the label includes: product name "PVC Insulated/Sheathed 4c×185mm² Underground Copper Power Cable"; model specification "4c×185mm²"; length "500m"; weight "about 425kg"; production batch number "XXXXXX"; implementation standard "GB/T 12706.1-2020"; production date "XXXX 年 XX 月 XX 日"; manufacturer name "XXXX Cable Co., Ltd."; contact information "XXXXXXXXXXX". In addition, warning signs such as "Do not invert", "Handle with care", "Moisture and sun protection" are pasted on the cable reel to remind transportation and loading and unloading personnel to operate correctly.

According to the transportation distance and customer requirements, road transportation, railway transportation or water transportation can be selected. For short-distance transportation (distance within 500km), road transportation is usually adopted, using large trucks to load cable reels. The length of the truck's carriage is not less than 6m, and the width is not less than 2.5m, which can accommodate the placement of cable reels. Road transportation has the characteristics of high flexibility and strong timeliness, and can directly deliver the cable to the construction site. For long-distance transportation (distance over 500km), railway transportation can be selected, with cable reels loaded on railway freight cars. Railway transportation has the advantages of large transportation volume, low cost and good stability. For areas with ports, water transportation can also be used to ship cable reels. Water transportation is suitable for large quantities of goods and long-distance transportation, with low cost but relatively long transportation time.

During transportation, the cable reel must be kept in an upright state, and it is strictly forbidden to lay it flat or upside down to prevent the cable from being damaged by extrusion. When loading and unloading the cable reel, special lifting equipment such as cranes and forklifts should be used, and the lifting capacity of the lifting equipment should be greater than the weight of the cable reel. When lifting, special lifting belts should be used, and direct lifting with steel wire ropes should be avoided to prevent damage to the cable reel and the cable. During the driving process of the transport vehicle, it is necessary to keep stable, avoid sudden braking, sharp turns and other operations, and prevent the cable reel from sliding in the carriage. Wooden wedges or baffles should be used to fix between the cable reels and between the cable reels and the carriage to reduce shaking during transportation. During transportation, the cable reel should be covered to prevent sun exposure, rain and dust pollution. For cables transported over long distances, the fixing of the cable reel and the appearance of the cable should be checked regularly, and problems should be dealt with in a timely manner.

After the customer places an order, the sales staff first confirms the product model specification, quantity, delivery date, delivery location and other information with the customer to ensure that the order information is accurate. Then, the sales staff transmits the order information to the production department and the warehouse department. The production department organizes production according to the order requirements to ensure that the products are completed on time. After the product production is completed, the warehouse department conducts incoming inspection on the products, and goes through the warehousing procedures after passing the inspection. Before the agreed delivery date, the warehouse department arranges goods preparation according to the order information, takes out the cable from the warehouse, and carries out packaging and marking. After packaging, the warehouse department contacts the transportation company, arranges transport vehicles, and notifies the transportation company of the cable's delivery information (such as product

name, model specification, quantity, transportation method, license plate number, etc.). After receiving the cable, the transportation company goes through the handover procedures with the warehouse department and then transports the cable to the delivery location according to the specified route and time. After shipment, the sales staff promptly informs the customer of the shipment information to facilitate the customer's preparation for receipt.

2. Delivery Time

For products in stock, they will generally be shipped within 1-3 working days after receiving the customer's payment or advance payment. For customized products, the production cycle is usually 7-15 working days, depending on the product specifications and quantity. After production is completed and passed inspection, shipment will be arranged within 1-2 working days. In case of special circumstances such as raw material shortages, equipment failures, or bad weather that may cause delivery delays, the sales staff will communicate with the customer in a timely manner, explain the reasons, and negotiate a new delivery date.

To enable customers to better understand the quality and performance of the product, the company can provide samples. Customers can apply for samples via phone, email, online consultation, etc., specifying the model specification, quantity, and other information of the required samples. After receiving the sample application, the company will prepare the samples within 2-3 working days. The length of the samples is usually 1m-3m to meet the customer's needs for inspecting the appearance, size, material, and performance of the cable.

For samples of regular models, the company usually provides them free of charge, but the customer needs to bear the transportation cost of the samples. Customers can choose to pay the freight by cash on delivery or prepay the freight to the company. For specially customized samples, due to the need for special production and processing, the company will charge a certain sample fee. The amount of the sample fee is determined according to the specification and processing difficulty of the sample, generally 2-3 times the unit price of the regular product. After the customer places a formal order, the sample fee can be deducted from the payment.

After the samples are prepared, the company will choose an appropriate express delivery method (such as DHL, FedEx, UPS, etc.) to send the samples to the customer. Before delivery, the samples will be properly packaged, placed in a hard carton, and filled with buffer materials such as foam in the carton to prevent damage during transportation. At the same time, the words "sample" and the customer's contact information will be marked on the sample package. After the sample is shipped, the company will promptly inform the customer of the express tracking number to facilitate the customer's inquiry of the sample's logistics information. If the customer has any questions about the sample after receiving it or needs further technical support, the company's technical personnel will provide timely answers.

The company promises that the produced PVC insulated/sheathed 4c×185mm² underground copper power cables comply with relevant national standards such as GB/T 12706.1-2020 and industry standards. The product quality warranty period is 2 years from the date of leaving the factory. Within the warranty period, if the product has quality problems (such as insulation breakdown, conductor breakage, sheath cracking, etc.) due to manufacturing defects, the company will provide free repair or replacement services. Customers need to provide relevant materials such as purchase invoices and photos of defective products to assist in determining the cause of the problem.

The company has a professional technical team to provide customers with comprehensive technical support. Customers can consult technical personnel about cable selection, installation, laying, maintenance, and other issues through phone, email, online platforms, etc. The technical team will provide professional solutions and suggestions according to the customer's specific situation. For large-scale construction projects, the company can dispatch technical personnel to the site to guide the installation and laying of cables, check the construction quality, and ensure that the cable installation meets the design requirements and safety standards.

If the cable fails during use, the customer can contact the company's after-sales service hotline. The after-sales staff will record the fault situation in detail and respond within 2 hours. For simple faults, technical personnel can guide the customer to solve them through phone calls or video calls; for complex faults that require on-site handling, the company will dispatch technical personnel to the site within 24-48 hours (depending on the distance) to carry out fault diagnosis and maintenance. If the fault is caused by product quality problems within the warranty period, the maintenance is free of charge; if the fault is caused by improper use, man-made damage, or beyond the warranty period, the company will charge reasonable maintenance fees and material fees.

The company attaches great importance to customer feedback and has established a sound customer feedback mechanism. Customers can put forward opinions and suggestions on product quality, service attitude, delivery time, etc., through the company's official website, customer service hotline, email, and other channels. The company arranges special personnel to sort out and summarize customer feedback, and holds regular meetings to discuss and study improvement measures. For reasonable suggestions, the company will adopt them in a timely manner and feed back the handling results to the customer within 5 working days. The company takes customer feedback as an important basis for improving products and services, and is committed to providing customers with more satisfactory products and services.