What should be noted in the process of purchasing wire and cable

Release time: 2024-08-09

In electric power, communication and many industrial fields, wire and cable as an important transmission medium, its quality is directly related to the stability and safety of the system. Therefore, in the process of purchasing wires and cables, it is necessary to choose carefully to ensure that the purchased products meet the relevant standards and requirements. We will start from the copper content, insulation materials, concentricity and other key points, to explore the issues that should be noted when purchasing wire and cable.

First, the copper content is sufficient

Copper as the main conductive material of wire and cable, its content directly affects the conductivity and load capacity of the cable. According to industry standards, high-quality wire and cable should use high-purity copper or high-quality copper as a conductor to reduce resistance and improve conductivity. During the procurement process, copper content can be tested by the following methods:

Chemical analysis method: This is a more accurate testing method, which quantifies the copper content in cables by reacting cable samples with reagents through a series of chemical reactions. This method requires a professional laboratory and experienced technicians to operate.

Photoelectric colorimetry: The spectra absorbed by copper ions in the cable are detected using a photoelectric colorimeter to derive the copper content. The method is simple to operate, but the detection accuracy is relatively low, suitable for rapid screening.

Electrochemical analysis method: Based on the principle of electrode reaction, the copper content in cables is detected through changes in electrochemical potential and electrolytic concentration. This method requires certain laboratory conditions and technical support, but the detection accuracy is higher than the photoelectric colorimetric method.

It is recommended to choose cable products with authoritative test reports when purchasing to ensure that the copper content meets or exceeds the national standards (e.g., GB/T 3956-2008, "Conductors of cables").

Second, whether the insulation material is qualified

Insulating material is an important part of the wire and cable, its quality is directly related to the insulation performance and safety of the cable. Qualified insulation materials should have good insulation resistance, heat resistance, aging resistance and mechanical strength.

Insulation resistance test: According to GB/T 3048.5-2007 standard, the insulation resistance should reach a certain value to ensure that the current flows according to the established route and prevent leakage current from causing safety accidents. The test can be conducted by voltage-current method or DC comparison method, and the measurement environment needs to strictly control the temperature and humidity.

Thermal aging test: By simulating a long time high temperature environment, observe the aging of the insulating material and evaluate its heat resistance and aging resistance. It is generally required to be continuously heated at a certain temperature (e.g. 150℃) for a certain period of time (e.g. 168 hours), and then tested for tensile strength, elongation at break and other performance indicators.

Procurement should be selected after rigorous testing and certification of insulation materials to ensure that they meet the relevant standards and regulations.

Third, whether the concentricity is qualified

Concentricity is an important indicator to measure the structural uniformity of wire and cable, unqualified concentricity may lead to eccentricity, distortion and other problems during the use of the cable, affecting transmission efficiency and safety.

Structural size testing: In accordance with the provisions of GB/T 2951-2008 "General Test Methods for Insulation and Sheathing Materials of Cables and Optical Fiber Cables", the structural dimensions of the cable's insulating layer, sheathing layer and other structural dimensions are measured accurately. Especially for products with large cable outer diameter, projectors and other equipment should be used to measure from two directions perpendicular to each other to ensure that the concentricity is up to standard.

Process control: the production process should be strictly controlled extrusion temperature, screw speed, hauling speed and other process parameters to ensure that the insulation layer and the sheath layer of uniform extrusion. At the same time, the mold configuration and cooling process also need to be strictly controlled to prevent improper process leading to unqualified concentricity.

Procurement can be viewed through the manufacturer's process control records and product quality inspection reports to understand the concentricity of the cable.

In the process of purchasing wires and cables, copper content, insulation materials, concentricity and other factors should be considered. By choosing cable products with authoritative inspection reports, strictly controlling the qualification of insulation materials, and paying attention to the level of process control of manufacturers, we can ensure that we procure high-quality, high-performance wire and cable products. This not only helps to improve system stability and safety, but also reduces maintenance costs and the risk of safety accidents caused by cable quality problems.

Hechang Electric, a professional wire and cable manufacturer, provides you with high-quality products, perfect service and supporting after-sales protection.

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