GB/T 42740-2023 in English

1. Background and significance of standard formulation

GB/T 42740-2023 "Safety Guidelines for Wires and Cables for Rail Transit" is a comprehensive standard formulated for the safety of wires and cables used in the rail transit field. With the rapid development of urban rail transit, higher requirements are placed on the safety and reliability of wires and cables used. The formulation of this standard aims to unify industry specifications, ensure the safe operation of wires and cables for rail transit under different environmental conditions, and provide clear technical guidance for the design, production and application of related products.

2. Main contents of the standard

2.1 Environmental conditions along rail transit

The environment along the rail transit project is complex and the climate is changeable. The northern region is cold and dry in winter, the southern region is humid and rainy, the southwestern plateau region has a large temperature difference between day and night, and the eastern coastal region is often affected by typhoons. This standard classifies the environmental conditions in different regions in detail and puts forward corresponding cable use requirements.

2.2 Classification and identification of wire and cable products

3. Technical requirements and implementation suggestions

3.1 Principles for the selection of wires and cables

Select appropriate products according to the rated voltage of the power supply system, distribution system and electrical equipment. In areas with severe electromagnetic interference, shielded cables should be used first.

3.2 Precautions for installation and laying

• Temperature control:The operating environment temperature should not exceed the range specified in the product standard, especially in high and low temperature environments, corresponding protective measures should be taken.
• Mechanical stress:The cable should have sufficient mechanical strength and avoid excessive stretching or bending during laying.
• Fireproof performance: In confined areas such as underground spaces or tunnels, it is recommended to use halogen-free low-smoke flame-retardant cables.

3.3 Safety inspection and maintenance

After the laying of wires and cables is completed, insulation resistance tests and withstand voltage tests should be carried out, and the reliability of joints and connectors should be checked regularly. Especially in high humidity or corrosive environments, protective measures need to be strengthened.

4. Comparative analysis of standard frameworks

5. Implementation Suggestions

To ensure the effective implementation of GB/T 42740-2023 standard, it is recommended to take the following measures:

• Strengthen technical training:Provide standard interpretation and application training to relevant practitioners.
• Establish a supervision mechanism:Formulate a strict inspection and acceptance process to ensure that product quality meets the standard requirements.
• Promote technological innovation:Encourage enterprises to develop more efficient and safer wire and cable products for rail transit.