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The SMT workshop has clear requirements for temperature and humidity, regarding its importance to SMT.
SMT workshop temperature and humidity requirements and management methods
1. Requirements of temperature and relative humidity in SMT workshop:
Temperature: 24±2 degree Celsius
Humidity: 60±10%RH
2. Temperature and humidity testing equipment:
PTH-A16 precision temperature and humidity inspection instrument
1. Using Pt100 platinum resistance as the temperature sensor to ensure the accuracy and stability of the temperature measurement;
2. The relative humidity is measured by the ventilated dry-wet bulb method, which avoids the influence of wind speed on humidity measurement;
3. Resolution: temperature: 0.01 degree Celsius; humidity: 0.01%RH;
4. Overall error (electrical measurement + sensor): temperature: ±(0.1～0.2) degree Celsius; humidity: ±1.5%RH.
SMT workshop temperature and humidity requirements and management methods
3. Relevant regulations for environmental control in SMT workshop:
1. The parameter values are set by the SMT engineering department according to product requirements and seasonal changes.
2. The placement of the daily thermometer and hygrometer: an electronic pointer type dry and wet bulb thermometer and hygrometer are used, placed in the densest area of the machine, so that the most significant temperature and humidity changes can be collected.
3. The recording period of the thermometer and hygrometer is set to 7 days, and the recording table is changed every Monday at 7:30 in the morning. The replaced record sheet is stored in a specific folder, and the retention period is at least 1 year. A new record sheet can be applied to the Engineering Department. The start date must be stated on the form. When the record sheet is replaced, the record start time must be the same as the replacement form.
4. The switch of the indoor air-conditioning system and the humidity control system (humidifier, humidifier) switch are handed over to the relevant personnel of the Public Works Department, and personnel from other departments are not allowed to use them without authorization.
5. The exhaust port of reflow soldering must be cleaned once a month to prevent excessive water accumulation. 6. Turn off the air outlet switch of the air-conditioning system on holidays and holidays, and ask the Public Works Department not to turn off the air-conditioning system air outlet switch to prevent condensation on the inner wall of the machine.
4. Requirements for daily inspection of temperature and humidity
1. The inspection work is in charge of the SMT Engineering Section.
2. The number of inspections is four times a day, divided into four time periods: 7:00~~12:00; 12:00~~19:00; 19:00~~2:00; 2:00~~7 :00. (Twice each for day shift and night shift)
3. The results of each inspection must be recorded in the prescribed form, and the name of the inspector must be signed.
4. If the temperature and humidity value on the temperature and humidity record sheet is within the required range, write "OK" in the two columns of the
5. The person in charge of the SMT engineering section should immediately notify the person in charge of the production section after receiving the notice, and may request to stop the machine if necessary, and notify the engineering section to check the air conditioning system and humidity control system.
6. After the temperature and humidity return to the required range, the person in charge of the SMT engineering department should immediately notify the production department to resume production.
7. It is not necessary to record the temperature and humidity on rest days or holidays.
