Underground Armoured Copper cables of series such as Cu U1000 Rvfv, Arvfv, Rvfv-K, and Xav have their specification parameters precisely designed for underground high-power transmission scenarios, with all indicators complying with relevant standards.

Current-carrying capacity is a core parameter reflecting their transmission capacity. In a standard underground laying environment (soil temperature 20°C, direct burial laying), the current-carrying capacity of 1X95mm² cables is approximately 180-220A; that of 1X300mm² cables can reach 300-350A. If in an underground environment with high soil humidity or slight corrosiveness, the current-carrying capacity needs to be multiplied by a correction factor of about 0.9; when the soil temperature exceeds 25°C, the correction factor is adjusted to 0.85-0.9.

The outer diameter of the cables varies depending on the specifications. The outer diameter of 1X95mm² cables is approximately 28-32mm; that of 1X300mm² cables is approximately 45-50mm. Such outer diameter sizes can not only adapt to the laying space of underground pipes or direct burial but also ensure the stability of the armoured layer and internal structure. Their rated voltage is 1000V, meeting the needs of high-voltage power transmission. The DC resistance of Copper Conductors is strictly controlled. At 20°C, the DC resistance per kilometer of 1X95mm² cables is not more than 0.193Ω; that of 1X300mm² cables is not more than 0.058Ω, effectively reducing energy loss during transmission. In addition, the protection level of the armoured layer reaches IP66, which can resist soil extrusion, groundwater immersion, etc., and adapt to complex underground environments.

With their underground armoured design and transmission capabilities of different specifications, this series of cables plays an important role in various underground power transmission scenarios.

1X95mm² cables are suitable for underground branch line transmission. In the underground power distribution system of residential communities, they can transmit electricity from the community's main distribution room to the underground distribution branch boxes of each building, providing stable support for residents' electricity use; in the underground branch lines of small industrial parks, connecting the power distribution points of each workshop, this specification of cable can meet the power needs of small and medium-sized equipment in the workshop. In the underground lighting branch lines of municipal roads, it can distribute electricity from the main line to each street lamp base, ensuring stable power supply for road lighting.

1X300mm² cables are suitable for underground main line transmission. The underground main cables in industrial parks can transmit external high-voltage electricity to the park's main distribution room, and then the main distribution room distributes it to various areas. Their large current-carrying capacity can meet the simultaneous operation of many large equipment in the park; the main lines of large municipal underground power grids, which undertake the main power transmission task in a certain area of the city, this specification of cable can ensure efficient power transmission. In addition, the underground main Power Lines of large industrial and mining enterprises, connecting the factory's own Power Station with each production workshop, also rely on this specification of cable to ensure power supply.

The Arvfv model has obvious advantages in special underground environments due to its possible corrosion resistance. In underground power lines near chemical plants, the soil may contain slightly corrosive substances, and this model of cable can resist corrosion and extend service life; in underground laying scenarios in coastal areas, due to the high salt content in the soil, this model of cable can reduce the erosion of salt spray on the cable.

The Xav model has outstanding performance in structural stability and is suitable for scenarios with complex underground laying environments. For example, in power lines passing through underground rock layers, which may be squeezed by rocks during laying, this model of cable can maintain structural stability; in the supporting power lines along underground rail transit, the vibration generated by train operation is relatively large, and this model of cable can reduce the impact of vibration on transmission.

In terms of material selection and style design, this series of cables fully combines the environmental characteristics and transmission needs of underground laying, achieving the unity of performance and practicality.

In terms of materials, the conductor is made of high-purity copper with a purity of more than 99.95%. High-purity copper has excellent conductivity, can efficiently transmit large currents, and reduce energy loss during transmission. At the same time, the copper conductor has good ductility and toughness, and is not easy to break even when encountering a certain degree of bending or soil extrusion during underground laying, ensuring the continuity of transmission.

The insulation layer is made of high-voltage resistant XLPE (cross-linked polyethylene) material, which has strong temperature resistance. The long-term working temperature can reach 90°C, and it can withstand a high temperature of 130°C during short-term overload, and is not easy to have insulation aging in the underground environment. This material has high insulation resistance, can effectively isolate current, prevent electric leakage accidents, and has good chemical stability, which is not easy to be affected by underground moisture and slightly corrosive substances.

The armoured layer is made of galvanized steel strip or aluminum alloy strip, which has excellent mechanical strength and corrosion resistance. The galvanized steel strip armoured layer can resist the extrusion of underground soil and the collision of stones, protecting the internal core and insulation layer; the aluminum alloy strip armoured layer is relatively light in weight, and has certain Flexibility, which is convenient for laying, and has good corrosion resistance, suitable for humid underground environments.

The outer sheath is made of weather-resistant PVC (polyvinyl chloride) or PE (polyethylene) material. The PVC Sheath has high mechanical strength and wear resistance, and can adapt to friction during underground laying; the PE sheath has good low-temperature resistance, is not easy to crack in the underground environment of cold areas, and has strong chemical corrosion resistance.

In terms of style, all are single-core designs, and the core color is red or brown, which is easy to identify. The armoured layer adopts an interlocking armoured structure, which not only ensures the protective performance but also has certain flexibility, facilitating underground bending and laying. The surface of the cable is smooth, printed with model, specification, rated voltage, manufacturer and other marks, which is convenient for construction and later maintenance. Different models have differences in details. For example, the Arvfv model may have an additional anti-corrosion coating outside the armoured layer, and the Rvfv-K model may optimize the thickness distribution of the insulation layer.

The production process of this series of cables focuses on the needs of underground armouring and high-power transmission, with each link strictly controlled to ensure product quality.

The production of Copper Conductors is a basic link. High-purity electrolytic copper rods are selected, and the copper rods are drawn into Copper Wires with a diameter suitable for the corresponding specification through a continuous wire drawing process. During the wire drawing process, the wire drawing speed and die precision are controlled to ensure uniform diameter of the copper wires. Subsequently, multiple copper wires are stranded to form a single-core conductor, and the tension is kept uniform during stranding to enhance the mechanical strength and conductivity of the conductor.

The insulation extrusion link is crucial. The XLPE material is put into an extruder, heated and melted at a temperature of 120-150°C, and uniformly coated on the surface of the copper conductor through a precision mold to form an insulation layer. The thickness of the insulation layer of 1X95mm² cables is approximately 2.0-2.5mm; that of 1X300mm² cables is approximately 3.0-3.5mm. During the extrusion process, an online thickness gauge is used to monitor the thickness of the insulation layer in real time to ensure that the deviation does not exceed ±0.1mm. After that, the insulation layer is cross-linked, and the XLPE molecules form a three-dimensional network structure through steam cross-linking to improve insulation performance and temperature resistance.

The production of the armoured layer is the key to ensuring underground protection performance. For cables armoured with galvanized steel strips, the galvanized steel strips are longitudinally wrapped outside the Insulated Core through special equipment. The overlapping width of the steel strips is 15%-20% of the width of the steel strips, and they are firmly connected by high-frequency welding to form a closed armoured layer. For cables armoured with aluminum alloy strips, the interlocking armouring process is adopted, and the aluminum alloy strips are curled through a mold and 咬合 with each other to form a continuous armoured structure. The thickness of the armoured layer depends on the specification. The thickness of the armoured layer of 1X95mm² cables is approximately 1.5-2.0mm; that of 1X300mm² cables is approximately 2.5-3.0mm.

Outer sheath extrusion provides the last layer of protection for the cable. PVC or PE material is heated and melted in an extruder and uniformly coated outside the armoured layer. The extrusion temperature is controlled at 160-180°C, and the sheath thickness of 1X95mm² is approximately 2.0-2.5mm; that of 1X300mm² is approximately 3.0-3.5mm. After extrusion, it is quickly cooled and shaped in a cold water tank to make the sheath closely adhere to the armoured layer. For models with anti-corrosion characteristics such as Arvfv, after the sheath is extruded, an additional anti-corrosion coating is sprayed and cured.

During the production process, a number of tests are required for each batch of cables, including insulation resistance test, voltage withstand test (applying 10kV voltage for 5 minutes without breakdown), and armoured layer adhesion test, to ensure that the products meet the standards.

The packaging of this series of cables focuses on protecting the cables from damage during transportation and storage, and the packaging method is designed in combination with its armoured characteristics and underground laying.

For long-length cables (100 meters and above), wooden cable reels are used for packaging. The wooden reels are made of high-strength pine wood, and the load-bearing capacity depends on the cable specification. The load-bearing capacity of the wooden reel corresponding to 1X95mm² cable is not less than 800kg; that corresponding to 1X300mm² cable is not less than 1500kg. The cables are neatly wound on the wooden reels, and the winding tension is controlled at 80-100N to avoid deformation of the armoured layer due to over-tightening or looseness due to over-loosening. Both sides of the wooden reel are equipped with baffles with a thickness of 30mm, and rubber buffer strips are added at the edges of the baffles to prevent the cable from colliding with the baffles during transportation. The outer layer of the cable is wrapped with a moisture-proof wrapping film with a thickness of 0.08mm and a winding overlap rate of 50%, which can effectively isolate moisture and dust. The surface of the wooden reel is printed with model, length, weight, production batch number and other information with waterproof ink, and pasted with warning signs such as "Up" and "Anti-pressure".

Short-length cables (10-50 meters) are packaged in high-strength wooden boxes. The wooden boxes are made of multi-layer plywood with a thickness of 20mm, and 8mm thick pearl cotton buffer layer is laid inside. The cable is coiled into a disc with a diameter of about 50cm and fixed in the wooden box with a special strapping to avoid shaking during transportation. Two bags of desiccant (100g each) are placed in the box to prevent the cable from getting damp. Product information and transportation warning signs are printed on the outside of the box, and two hand holes are opened on the side for easy manual handling.

The packaging materials meet environmental protection requirements, and the wooden packaging has been fumigated to meet export quarantine standards. All packages have passed the drop test (no damage when dropped from a height of 1.5m) and pressure test (withstanding 500kg pressure for 2 hours without deformation) before leaving the factory to ensure transportation safety.

The transportation of this series of cables needs to combine their weight, armoured characteristics and the use scenario of underground laying, select an appropriate transportation method and take protective measures.

The transportation method is selected according to the transportation distance and quantity. For short-distance transportation (within 300 kilometers), trucks with hydraulic tailboards are used, and anti-skid rubber pads are laid in the carriage. The thickness of the rubber pads is 10mm, and the friction coefficient is not less than 0.8 to prevent the cable reels from sliding. A single truck can load no more than 8 wooden reels of 1X95mm² cables and no more than 4 wooden reels of 1X300mm² cables. When loading, the wooden reels are separated by wooden partitions with a thickness of 20mm to prevent mutual collision. For long-distance transportation (more than 300 kilometers), railway flat cars are selected, and the wooden reels are fixed on the carriage load-bearing frame through steel wire ropes. Rubber pads are set at the fixed points to avoid the steel wire ropes from damaging the wooden reels. The diameter of the steel wire rope is not less than 12mm, and each wooden reel is provided with at least 4 fixed points. Large quantities of export transportation use container shipping, with ventilation devices set in the containers to control the humidity below 60%.

Targeted protective measures should be implemented during transportation. When transporting in rainy days, the cables are completely covered with rainproof cloth. The rainproof cloth is made of waterproof canvas with a thickness of 0.5mm. The edges hang down to the bottom of the carriage and are compacted with sandbags to prevent rainwater from seeping in. When transporting in high-temperature weather, avoid the cables being exposed to the sun for a long time. A sunshade can be installed on the top of the carriage to control the temperature in the carriage not to exceed 40°C. When transporting in low-temperature weather (below 0°C), if the cables need to be unloaded in a low-temperature environment, preheat the cables in advance to avoid the sheath from becoming brittle and damaged due to low temperature.

Forklifts or cranes are used for loading and unloading. The length of the forklift arm is not less than 1.8m, and the diameter of the crane's lifting rope is not less than 16mm. When loading and unloading large 规格 cables such as 1X300mm², special lifting tools must be used to avoid damaging the wooden reels and cables. It is strictly forbidden to use steel wire ropes to directly bind the outer sheath of the cable for hoisting to prevent damage to the sheath and armoured layer. During loading and unloading, the inclination angle of the cable reel does not exceed 15° to avoid the cable slipping from the wooden reel.

Regular inspections are required during transportation. Stop every 300 kilometers to check the fixing of the cables, and reinforce them in time if they are loose. The driving speed of the transport vehicle does not exceed 70km/h to avoid displacement of the cable reels caused by sudden braking.

The shipment process of this series of cables is standardized and orderly to ensure that the cables are delivered on time and accurately.

In the order confirmation link, after receiving the order, the sales staff checks the product model, specification, quantity, delivery address, delivery time and other information with the customer within 3 hours. After confirmation, an order number is generated and entered into the system. At the same time, check the customer's payment status, and arrange stock preparation after collecting the advance payment (usually 30% of the total amount) according to the contract agreement.

The stock preparation process is efficiently connected. Warehouse managers retrieve the inventory according to the order number, and transfer the cables to the inspection area after checking that the cable identification is consistent with the order information. Quality inspectors conduct random inspections on the cables, including appearance (no damage to the sheath, no looseness of the armoured layer, clear identification), insulation resistance (measured with a 2500V megohmmeter not less than 1000MΩ), and length (error not exceeding ±0.5%). After passing the random inspection, an outgoing inspection report is issued. The stock preparation cycle is usually 2-3 working days, and the stock preparation cycle for special specifications or customized models is determined according to the production progress, with a maximum of no more than 7 working days.

Transportation arrangements are accurately connected. The logistics specialist selects the optimal transportation method according to the delivery address, cable specification and quantity, confirms the delivery time window with the customer (accurate to 1 day), and notifies the customer of the arrival information 48 hours in advance, including the license plate number of the transport vehicle, the driver's contact information, the estimated arrival time, and the unloading equipment to be prepared when arriving. For urgent orders, a special vehicle can be arranged for transportation to ensure delivery within 24 hours.

Shipment tracking is fully visualized. The location of the goods is monitored in real time through the logistics management system, and the transportation progress information is pushed to the customer every 8 hours, including the current location, estimated arrival time, transportation status, etc. In case of delays due to traffic control, bad weather, etc., communicate with the customer immediately and provide solutions (such as changing the transportation route, urgently allocating spare goods). After the goods are delivered, assist the customer in checking the quantity and appearance, guide the customer to conduct a preliminary acceptance, and after confirmation, the customer signs for receipt, and the receipt is uploaded to the system for archiving in real time.

This series of cables provides sample services to help customers understand product performance and adaptability in advance.

The sample application process is simple. Customers can apply through the official website online application, phone, email, etc., stating the required sample model, specification, quantity (usually no more than 2 meters) and purpose (such as testing, project trial).

When applying, it is necessary to provide information such as company name, contact person, contact information, and project name. Sample applications will receive a response within 1 working day.

Sample preparation is strictly standardized. Samples are cut from mass-produced qualified products. The length of 1X95mm² samples is 1.5 meters, and the length of 1X300mm² samples is 2 meters, retaining the complete armoured layer, sheath, and core. Both ends of the samples are sealed with insulating 封头 to prevent the core from getting damp and damaged. A sample label is attached to the samples, indicating product model, specification, production batch number, cutting date and other information, as well as a copy of the product test report and product manual.

Samples are sent by express. The packaging uses hard plastic pipes (1X95mm² samples use plastic pipes with a diameter of 50mm, and 1X300mm² samples use plastic pipes with a diameter of 80mm). The samples are put into the pipes, and both ends are fixed with foam plugs to prevent bending during transportation. The express waybill is marked with "Sample", "Valuable Item", and "Handle with Care", and the next-day or second-day delivery service is selected to ensure that the samples are delivered within 48-72 hours. Samples are provided free of charge, and the express fee is to be paid by the customer.

Sample tracking service is attentive. After the samples are sent, the customer is sent the express waybill number, logistics inquiry link, and contact information of the tracking person. Within 3 working days after the customer receives the samples, the sales staff will make a return visit to understand the sample usage and answer relevant questions (such as testing items, laying precautions, etc.). If the customer needs further performance testing (such as corrosion resistance testing, current-carrying capacity testing), guidance on testing methods and relevant technical parameters can be provided.

The after-sales service system of this series of cables is perfect, providing customers with full-cycle support to ensure reliability during underground laying and use.

In terms of quality assurance, the product warranty period is 3 years, starting from the date of customer's signature. Within the warranty period, if the cable fails due to its own quality problems (such as insulation layer breakdown, armoured layer falling off, sheath cracking, etc.), the customer can apply for after-sales service with the purchase contract, fault photos, and test report. After receiving the application, the after-sales specialist will respond within 2 hours and arrange for technical personnel to arrive at the site for testing within 48 hours. After confirming the quality problem, new cables will be provided to the customer free of charge, and the round-trip transportation costs and on-site replacement labor costs will be borne.

The technical support team is composed of engineers with more than 8 years of experience, providing 7×24-hour consulting services. When customers are in the cable selection stage, engineers provide selection suggestions and current-carrying capacity calculation tables according to underground laying environment (soil type, humidity, corrosiveness, etc.), transmission power, laying method and other parameters; during laying, on-site guidance can be provided, such as laying depth (not less than 0.7 meters), bending radius (not less than 15 times the outer diameter of the cable), armoured layer grounding method, etc.; during use, they answer questions about maintenance, such as regular inspection cycle (recommended once a year), inspection items (insulation resistance, armoured layer integrity, sheath appearance, etc.), and cleaning methods.

Maintenance services are for cables that have exceeded the warranty period. After on-site inspection by technical personnel, maintenance plans and cost quotations are provided, and maintenance is carried out after customer confirmation. Maintenance contents include sheath repair, armoured layer reinforcement, insulation layer repair, etc. A 6-month warranty is provided after maintenance. For cables that cannot be repaired, a trade-in service can be provided, and old cables are recycled at a discount based on weight and condition, with the discount ratio being 10%-20% of the price of new cables.

The regular return visit mechanism is normalized. When customers use the cables for 3 months, 6 months, 1 year, and 2 years, after-sales personnel will make return visits, including telephone return visits and on-site visits (for large projects), record the cable operation status, changes in the laying environment, etc., and collect customer opinions and suggestions. Product and service optimization is carried out based on return visit data. For example, in response to the problem of strong soil corrosiveness reflected by customers in a certain area, the thickness of the anti-corrosion coating of the Arvfv model cables supplied to that area is increased in subsequent production. At the same time, the electronic version of the "Underground Armoured Cable Maintenance Manual" and related maintenance videos are pushed to customers to provide professional maintenance knowledge.