High precision gas distribution instrumentIt is a precision equipment used for preparing specific concentration standard gases, widely used in environmental monitoring, industrial testing, laboratory calibration and other fields. Its operational standardization directly affects the accuracy of gas distribution and equipment life. The following are step-by-step operation specifications and core precautions for easy implementation.

1、 Operating standards (step-by-step)

1. Preparation before startup (checklist inspection)

2. Startup and parameter settings

Power on: Connect the device to the main power supply, press the power button, and wait for the instrument to complete self check (if self check fails, stop the machine for troubleshooting).

Choose gas distribution mode: Choose dynamic or static gas distribution mode according to the demand, and prioritize dynamic mode for conventional high-precision gas distribution.

input parameters

Set target gas concentration: Accurately input the required standard gas concentration value (units: ppm, ppb,%).

Set the carrier gas flow rate and feed gas flow rate: calculate based on the equipment range and gas distribution formula, or call the built-in gas distribution scheme of the equipment.

Set valve timing: Set the continuous valve timing or single valve volume as needed.

Parameter confirmation: After verifying that the input parameters are correct, save and enter the standby state.

3. Gas distribution operation

Open the gas source: first open the pressure reducing valve of the carrier gas cylinder, slowly adjust it to the set pressure, and then open the pressure reducing valve of the raw material gas; Observe the pneumatic pressure gauge to ensure stable pressure.

Start operation: Press the "Start" button, and the instrument will automatically mix gas according to the set parameters; Real time observation of the display screen, monitoring whether parameters such as flow rate and concentration are stable.

Stable sampling: Run the gas distribution for 5-10 minutes until the parameters are stable before sampling or outputting standard gas; Ensure that there is no dead volume in the sampling pipeline during sampling.

4. Shutdown process

Stop gas distribution: Press the "stop" button to stop the supply of raw material gas to the instrument. Keep the carrier gas blowing the pipeline for 3-5 minutes to remove residual raw material gas.

Turn off the gas source: first turn off the raw gas cylinder and pressure reducing valve, then turn off the carrier gas cylinder and pressure reducing valve; Evacuate residual gases in the pipeline (toxic gases need to be introduced into the exhaust treatment device).

Turn off the device: After confirming that there is no pressure in the gas circuit, turn off the instrument power and disconnect the main power supply.

Record ledger: Fill in operation records, including gas distribution date, target concentration, actual concentration, operating time, equipment status, etc.

2、 Core precautions

1. Safety precautions

Gas safety:

When handling flammable gases such as hydrogen and methane, open flames are strictly prohibited on site, and explosion-proof equipment and flammable gas detectors should be equipped.

Toxic and harmful gases (such as hydrogen sulfide and carbon monoxide) must be operated in a fume hood, and operators must wear gas masks and protective gloves.

Special corrosion-resistant pipelines and joints are used for corrosive gases such as chlorine and ammonia to prevent leakage and corrosion of equipment and personnel.

Pressure safety: It is strictly prohibited to operate under overpressure. The pressure reducing valve should be adjusted slowly to prevent damage to the instrument sensor caused by sudden pressure rise.

Electrical safety: Reliable grounding of equipment, avoiding operation in humid environments, and preventing short circuits and electric shock.

2. Precautions for accuracy assurance

Pipeline cleaning: Before the first use or change of gas type, blow the pipeline with carrier gas for 10-15 minutes to remove impurities and residual gas inside the pipeline.

Calibration cycle: Regularly (usually every 3-6 months) calibrate the instrument flow meter and concentration sensor using certified standard gases to ensure gas distribution accuracy.

Gas purity: The purity of the carrier gas should be ≥ 99.999%, and the raw gas should use certified standard gas to avoid impurities affecting the gas distribution results.

Avoid interference: During the gas distribution process, avoid frequent touching of equipment and adjusting valves to prevent flow fluctuations; The fluctuation of environmental temperature should not exceed ± 2 ℃.

3. Maintenance precautions

Daily cleaning: Regularly wipe the instrument casing and clean the dust and oil stains at the air circuit joints.

Replacement of vulnerable parts: Regularly check the sealing rings of the pipeline and pressure reducing valve, and replace them in a timely manner after aging; When the flow meter filter element is clogged, disassemble, clean or replace it.

Moisture and dust prevention: When the equipment is idle, cover it with a dust cover to keep the interior dry; When not in use for a long time, turn on the power once a month to prevent component aging.

Fault handling: In case of equipment alarm or abnormality, immediately stop the machine, investigate issues such as gas source, pipeline, parameter settings, etc., and strictly prohibit operation with faults; Contact the manufacturer's after-sales service for complex faults.

IIIHigh precision gas distribution instrumentQuick troubleshooting of common faults

Fault phenomenon	Possible reasons	Troubleshooting methods
Low gas concentration	Insufficient pressure of raw gas; Pipeline leakage; The flow meter is inaccurate	Check the pressure of the raw gas cylinder; Soap water detection pipeline leakage; Calibrate flow meter
Large concentration fluctuations	Unstable gas source pressure; Environmental vibration; Sensor not calibrated	Replace the stable gas source; Stay away from vibration sources; Re calibrate the sensor
The instrument cannot be turned on	The power supply is not connected; Fuse blown	Check the power socket; Replace the matching specification fuse