The laboratory gas system is a key infrastructure to ensure experimental safety and data accuracy. The inspection and maintenance of the Tianjin laboratory gas system after installation should follow the principles of systematization and standardization.

The following is an explanation from four dimensions: acceptance inspection of Tianjin laboratory gas circuit installation, key points of daily maintenance, regular in-depth maintenance, and emergency response mechanism:

1、 Installation acceptance inspection: Ensure initial safety

1. Airtightness test

Method: Use leak detector or professional leak detector to inspect all pipeline connections, valves, and joints one by one, and observe whether there are bubbles or pressure drops.

Standard: Under rated pressure, a pressure drop of no more than 2% within 24 hours is considered qualified.

Key areas: welding points, threaded connections, quick couplings, pressure reducing valves, and pipeline interfaces.

2. Pressure and flow verification

Pressure testing: Verify whether the pressure of each section of the system meets the design requirements through a pressure gauge.

Flow testing: Use a flow meter to measure the actual flow rate at the terminal gas point to ensure that it meets the requirements of the experimental equipment.

Dynamic adjustment test: Simulate actual usage scenarios to verify the adjustment accuracy and stability of pressure reducing valves and regulating valves.

3. Material and identification verification

Material compliance: Confirm that the pipeline and valve materials meet the gas characteristics (such as stainless steel for corrosive gases and copper for high-purity gases).

Integrity of identification: Check whether the pipeline flow direction identification, gas type identification, and hazard warning identification are clear and accurate to avoid misoperation.

2、 Key points for daily maintenance of air circuit installation in Tianjin laboratory: preventive management

1. Appearance and basic inspection

Daily inspection: Check whether the pipeline is deformed, corroded, or leaking, whether the valve is in the correct opening and closing state, and whether the pressure gauge reading is abnormal.

Environmental monitoring: Ensure that the gas path system is kept away from heat sources and corrosive substances, with good ventilation, and avoid direct sunlight that can cause pipeline aging.

2. Pressure and flow monitoring

Record data: Regularly record system pressure and flow data, establish trend analysis charts, and promptly detect abnormal fluctuations.

Calibration of pressure regulating valve: Use a standard pressure source to calibrate the pressure regulating valve every quarter to ensure that the output pressure is stable within the range of ± 1% of the set value.

3. Maintenance of filters and dryers

Replacement cycle: Regularly replace the pre filter according to the gas purity requirements.

Regeneration treatment: Perform regeneration operation on the molecular sieve dryer according to the instructions to restore adsorption capacity.

3、 Regular deep maintenance of Tianjin laboratory gas circuit installation: systematic guarantee

1. Pipeline cleaning and passivation

Cleaning frequency: High purity gas pipelines are cleaned every 1-2 years, while ordinary gas pipelines are cleaned every 3-5 years.

Method: Use a specialized cleaning agent to cycle and rinse to remove impurities such as oil stains and metal ions, and then blow dry with high-purity nitrogen gas.

Passivation treatment: Pickling and passivating stainless steel pipelines to form a dense oxide film and prevent corrosion.

2. Valve and joint maintenance

Disassembly inspection: Disassemble valves and joints every 2-3 years, check for aging and cracking of seals, and replace them if necessary.

Lubrication and maintenance: Apply special lubricating grease to moving parts such as ball valves and needle valves to ensure that the switches are flexible and not stuck.

3. Safety device testing

Safety valve calibration: Send the safety valve for inspection every year to ensure that the popping pressure meets the design value.

Alarm system testing: Simulate scenarios such as pressure exceeding limits and leaks to verify the sensitivity and reliability of the sound and light alarm device.