Conductor Material: The conductor of THW building wire uses 19 strands of soft-drawn copper, with a copper purity of more than 99.95%. The soft-drawing process involves multiple stretching of the copper rod followed by annealing, which gives the copper wire excellent Flexibility. This flexibility allows the wire to bend easily in complex Building Wiring environments, facilitating pipe threading and bypassing obstacles, greatly reducing construction difficulty. The high-purity copper material ensures good conductivity, with a conductivity close to 100% IACS (International Annealed Copper Standard), which can effectively reduce energy loss during current transmission and improve power utilization efficiency. At the same time, copper has good oxidation resistance. During long-term use, the surface of the conductor is not easy to oxidize and rust, which can maintain stable conductivity and extend the service life of the wire.

Insulation layer material: The insulation layer is made of high-quality PVC (polyvinyl chloride) material, which has undergone special formula treatment and has excellent insulation performance, with a volume resistivity greater than 1×10¹⁴Ω·cm. It can effectively block current, prevent electric leakage accidents, and ensure electrical safety. The PVC Insulation layer also has good moisture resistance. In humid environments, its insulation performance will not decrease significantly, making it suitable for wiring in humid areas such as underground garages, bathrooms, and kitchens. In addition, it has certain chemical corrosion resistance, can resist erosion by common acids and alkalis, and can be used in some industrial environments with slight chemical pollution. At the same time, PVC material has good mechanical strength, can withstand certain external extrusion and friction, and protect the internal conductor from damage.

Style design: The wire is cylindrical in overall shape, with a smooth and flat surface, without defects such as burrs, bubbles, or scratches. This not only ensures the appearance of the wire but also reduces resistance during wiring, facilitating pipe threading operations. In terms of color, common colors include black and gray, which are relatively calm, not easy to get dirty in building concealed works, and also convenient to distinguish from other lines with different functions, reducing the probability of wiring errors. The length of the wire can be customized according to customer needs, with common specifications such as 100 meters, 200 meters, and 500 meters, which can meet the wiring length requirements of different construction projects. Each coil of wire is neatly wound on a sturdy plastic or wooden reel, with baffles on both sides of the reel to prevent the wire from slipping during storage and transportation. The reel is printed with clear product identification, including model, specification, rated voltage, length, production date, manufacturer information, etc., which is convenient for users to identify and trace the product.

Copper rod preparation: First, high-purity electrolytic copper ingots are put into a melting furnace for smelting, with the temperature controlled at 1100-1200°C. During the smelting process, appropriate deoxidizers are added to remove oxygen and other impurities in the copper water, obtaining copper water that meets the purity requirements. The copper water is cast into copper rods with a diameter of approximately 8mm through a continuous casting machine. During the casting process, the casting speed and cooling intensity must be strictly controlled to ensure that the structure of the copper rod is uniform and dense, without defects such as pores and cracks.

Copper wire drawing and annealing: The copper rod is sent to a wire drawing machine for drawing, and through a series of dies of different sizes, the copper rod is gradually drawn into fine copper wires with a diameter of 0.8mm. During the drawing process, the drawing speed and mold lubrication must be controlled to ensure that the diameter of the copper wire is uniform and the surface is smooth. The drawn copper wire needs to be annealed. The copper wire is put into an annealing furnace, heated to 350-400°C under the protection of inert gas, and kept warm for a period of time to eliminate internal stress in the copper wire, improve its flexibility and conductivity, and make it a soft-drawn copper wire.

Copper wire stranding: According to the requirements of different specifications, 19 pieces of 0.8mm soft-drawn copper wires are stranded on a stranding machine. When stranding, an appropriate stranding pitch must be set. The stranding pitches of 2 AWG, 2/0 AWG, and 4/0 AWG are 15mm, 20mm, and 25mm respectively. An appropriate stranding pitch can ensure the roundness and flexibility of the conductor. During the stranding process, it is necessary to ensure that the copper wires are arranged neatly, without crossing, overlapping, loose strands, etc., to ensure the conductivity and mechanical strength of the conductor.

Insulation layer extrusion: The Stranded Conductor is sent to the extruder, and at the same time, PVC granules are added to the hopper of the extruder. The PVC granules are heated and melted in the extruder, with the temperature controlled at 160-180°C. The molten PVC material is pushed to the mold through the rotation of the screw, and evenly coated on the surface of the conductor to form an insulation layer of a certain thickness. The insulation layer thickness of wires of different specifications is different: 2 AWG is 1.0mm, 2/0 AWG is 1.2mm, and 4/0 AWG is 1.4mm. During the extrusion process, the extrusion temperature, speed, and pressure must be strictly controlled to ensure that the insulation layer has a uniform thickness, is closely combined with the conductor, and has no defects such as bubbles, pinholes, or eccentricity.

Cooling and solidification: The wire after extruding the insulation layer immediately enters the cooling water tank for cooling, with the cooling water temperature controlled at 20-30°C. Through the rapid cooling effect of cold water, the PVC insulation layer is solidified and formed to ensure its dimensional stability and mechanical properties. The cooling time is adjusted according to the specifications of the wire and the extrusion speed, generally 3-5 minutes, to ensure that the insulation layer is completely solidified.

Spark detection: The cooled wire must pass through a spark tester for insulation performance detection. The tester applies a high voltage of 3000V to the surface of the wire. If there are defects such as pinholes or cracks in the insulation layer, spark discharge will occur, and the equipment will automatically alarm and mark, so that unqualified products can be removed in time to ensure that the insulation performance of the wire meets the standard.

Printing identification: Product information is printed on the surface of the wire through a printing machine, including model, specification, rated voltage, temperature resistance level, execution standard, manufacturer name, production date, etc. The printing uses wear-resistant ink to ensure that the printing is clear and firm, not easy to fall off, facilitating product identification and traceability.

Take-up and packaging: Qualified wires are sent to the take-up machine and wound on plastic or wooden reels according to the set length (such as 100 meters, 200 meters, 500 meters, etc.). During the take-up process, the tension must be controlled to ensure that the wires are wound neatly and tightly without looseness or knotting. After winding, the wires are packaged, and the reels are wrapped tightly with plastic film to prevent dust and moisture from entering and protect the wires from damage.

Finished product inspection: Sampling inspection is carried out on the packaged finished wires. The inspection items include conductor resistance, insulation resistance, voltage withstand strength, outer diameter size, printing clarity, etc. Only products that fully meet the standards can leave the factory to ensure high-quality wire products for customers.

Quality guarantee: The product has a warranty period of 10 years. During the warranty period, if there is a quality problem with the product itself (such as insulation layer aging and cracking, conductor breakage, failure to meet insulation performance standards, etc., which are not caused by human factors), the company will provide free repair or replacement services. Customers need to provide purchase certificates and photos or videos of the faulty parts. After verification by the company's technical personnel, a solution will be given within 7 working days.

Technical support: If customers encounter any technical problems during the installation, laying, or use of the wires, they can call the company's after-sales service hotline at any time, or consult through online customer service, email, etc. The company's technical team is composed of experienced engineers who will provide professional answers and guidance within 24 hours, such as providing installation plan suggestions, solving technical problems during laying, and analyzing the causes of faults.

On-site service: For large engineering projects or complex fault situations, the company can arrange technical personnel to provide on-site services. Technical personnel will inspect the installation quality of the wires, guide construction personnel in correct laying and connection methods, assist customers in troubleshooting and maintenance, and ensure the normal operation of the electrical system. The cost of on-site service is determined according to the service content and distance, and a detailed quotation will be provided to customers in advance for confirmation.

Complaint handling: If customers have complaints about product quality, delivery delay, or service attitude, they can feedback through the company's after-sales complaint channels. The company will record and sort out the complaints, and assign special personnel to follow up and handle them. For general complaints, a reply will be given within 24 hours; for more complex complaints, the handling progress will be reported to customers regularly, and a final solution will be proposed within 10 working days to ensure customer satisfaction.

Return and exchange policy: If the received products have problems such as inconsistent specifications, damaged packaging, or quality defects, customers can apply for return or exchange within 15 days of receiving the goods. The company will verify the situation, and after confirmation, arrange for the return or exchange of the goods in a timely manner, and bear the relevant transportation costs. For customized products, return or exchange is only allowed if there is a quality problem caused by the company.

Regular follow-up: After the product is sold, the company will conduct regular follow-up visits to customers through telephone, email, or on-site inspections to understand the use of the product and collect customer opinions and suggestions. This helps the company continuously improve product quality and service levels and establish long-term and stable cooperative relations with customers.