Requirements for compressed air pipeline of lithium battery production workshop

The lithium battery production workshop has high requirements for compressed air pipelines, and it is necessary to comprehensively consider environmental characteristics, material selection, layout and installation and related standards. The following are specific specifications and basis:

1. environmental characteristics and requirements

1. air cleanliness:
   • need to achieve ISO level 7 or above, install the first effect, medium effect and high efficiency three-stage air filtration system.
   • The cleanliness of the inner surface of the workshop shall reach ISO 8, and the wall surface and ground shall be made of epoxy resin or color steel plate and other non-dust producing materials.
2. temperature and humidity control:
   • the temperature is stable at 20 ℃-25 ℃, the humidity is controlled at 40%-60%, and it is equipped with an accurate temperature and humidity control system.
3. Ventilation and exhaust:
   • ensure that the workshop is well ventilated and exhaust facilities are complete to prevent the accumulation of harmful gases (such as CO₂).
4. Static Electricity and Fire Protection:
   • install anti-static floor and grounding equipment, and strengthen fire and explosion prevention measures (such as firewall and explosion-proof door).

Material Selection of 2. Compressed Air Pipeline

1. material requirements:
   • stainless steel seamless steel pipe: as the preferred material, with high strength, corrosion resistance, high temperature resistance, in line with the lithium battery workshop high cleanliness requirements.
   • Disable Material: Avoid using carbon steel (easy to rust), galvanized pipe (coating fragile), PVC/PPR (poor corrosion resistance).
2. Attachment Matching:
   • pipe fittings (elbows, flanges, etc.) and valves shall be made of the same material as the pipe material, and shall be processed by hot pressing to ensure sealing.

3. Piping Layout and Installation Specification

1. layout principles:
   • shorten the length of the pipeline, reduce the local resistance parts such as elbows and branch pipes, and reduce the pressure loss.
   • The main pipeline is laid overhead along the wall or column (height ≥ 2.5m) to avoid crossing with other pipelines.
2. Installation Requirements:
   • welded connection when the nominal diameter is> 50mm, the stainless steel pipe shall be bottomed by argon arc welding.
   • Slope Settings: The gradient of airflow direction is ≥ 2 ‰, and the end of the main pipe is equipped with a water collector to prevent water accumulation.
   • Fixed bracket: Reasonable spacing to avoid vibration and noise transmission.
3. Inspection and acceptance:
   • clean the inside of the pipeline before installation, and conduct hydraulic test (1.5 times working pressure) and air tightness test (1.05 times working pressure) after completion.

4. related standards and specifications

1. follow standards:
   • code for Design of Industrial Metallic Piping GB50316
   • code for Design of Compressed Air Station (GB50029)
   • TSG D0001, Safety and Technical Supervision Code for Pressure Piping-Industrial Piping
2. special Area Requirements:
   • separate fire zones shall be set in the liquid injection area and high temperature room, and the pipeline shall meet the requirements of explosion-proof and corrosion resistance.

5. Lithium Battery Workshop Compressed Air System Upgrade Case

after a lithium battery factory upgraded the original galvanized pipeline to 304L stainless steel pipeline, the dew point of compressed air was increased from -20 ℃ to -40 ℃, and the yield of battery was increased by 12%. System maintenance costs are reduced by 35% and downtime due to pipeline corrosion is reduced by 80%.

Selection recommendations:

• when the budget is sufficient, stainless steel pipes are preferred to ensure long-term stable operation.
• Regularly check the pipeline corrosion, weld quality and tightness, and conduct professional flaw detection every 2 years.