When installing stainless steel ventilation ducts in subway tunnels, the following key issues need to be noted:

1. Structural strength and stability:

- Due to the complex underground environment and the possibility of geological activities, ventilation ducts must have sufficient structural strength to withstand possible vibration, pressure and deformation. For example, in earthquake-prone areas, it is necessary to design and install in accordance with higher seismic standards.

- Ensure that the support and fixing structure of the pipeline is firm and reliable to prevent the pipeline from loosening or falling off during operation.

2. Fire resistance:

- The subway is a densely populated public area, and fire protection is of Paramount importance. Stainless steel ventilation pipes should be made of materials with good fire resistance and meet relevant fire prevention standards and specifications. For example, the use of stainless steel with a certain fire rating ensures that structural integrity can be maintained in the event of a fire and does not contribute to the spread of the fire.

- During installation, pay attention to fireproof sealing treatment of pipe joints and holes to reduce the spread of smoke and flame in case of fire.

3. Corrosion resistance:

- The underground environment is usually humid and may contain corrosive substances. Stainless steel ventilation pipes should have excellent corrosion resistance to prevent corrosion and damage during long-term use.

- Regular inspection and maintenance of the pipeline, timely treatment of surface corrosion marks, to ensure the normal operation of the ventilation system.

4. Airtight performance:

- Good airtight performance helps to ensure ventilation and energy saving. During the installation process, the connection of the pipeline should be carefully treated to ensure that the seal is tight and there is no leakage.

- Conduct airtight performance test, if leakage is found, take timely measures to repair.

5. Space layout and size:

- Take full account of the limited space in the subway tunnel, rationally plan the layout and size of the ventilation ducts to avoid conflicts with other facilities.

- Ensure that piping is installed in a position that does not impede personnel access, equipment maintenance and emergency evacuation routes.

6. Noise control:

- The noise generated during the operation of the ventilation system should not exceed the specified standard, so as not to affect the comfort of passengers. Selecting low-noise fans and optimizing pipeline design can effectively reduce noise.

- Use sound-absorbing materials on the inner wall of the pipe to reduce the reflection and propagation of sound.

7. Cleaning and maintenance convenience:

- The design should take into account the convenience of post-cleaning and maintenance, and set up access ports and cleaning channels.

- During the installation process, ensure that the inside of the pipe is smooth and smooth, reduce the accumulation of dust and dirt.

8. Coordination with other systems:

- The installation of ventilation pipes should be coordinated with the power supply, communication, signal and other systems of the subway to avoid mutual interference.

- For example, when wiring pipes, avoid high-voltage cables and communication lines.

In short, the installation of stainless steel ventilation pipes in subway tunnels requires comprehensive consideration of various factors and strict compliance with relevant standards and specifications to ensure the safe, reliable and efficient operation of the ventilation system.