What should be paid attention to in the installation and construction of clean and dust-free workshop?

The installation and construction of the clean and dust-free workshop is a systematic project, which needs to focus on the three cores of cleanliness maintenance, pollution prevention and control, and system stability, and control the whole process from pre-construction preparation, process control to acceptance closing. The specific precautions are as follows:

Preparation before construction: Plan first to avoid mistakes at the source.

Scheme deepening and compliance check: confirm the cleanliness level, pressure difference, temperature and humidity and other parameters in combination with workshop uses (such as electronics, food and medicine), and check whether the scheme meets the corresponding industry standards (such as GB 50073 Code for Design of Clean Workshop, GMP). Clarify the layout of each functional area, ensure that the flow of people, logistics and air is reasonable, and avoid cross-pollution.

Personnel and material control: construction personnel should be trained in clean construction and equipped with clean clothes, dust-free shoes, gloves and other protective equipment; All incoming materials (such as color steel plate, high-efficiency filter and sealant) shall meet the requirements of cleanliness, and materials such as 304 stainless steel and food-grade epoxy resin shall be provided with test reports, which shall be classified and stored in a temporary clean warehouse after entering the site to prevent moisture and dust accumulation.

On-site isolation and protection: isolate the construction area from other areas of the factory with colored steel plates, set up independent personnel access channels and material entrances, and equip the entrance with a shoe cover machine and a sink to prevent external pollutants from being brought in.

Construction of main structure: Strictly control sealing and flatness.

Installation of enclosure structure: priority is given to tongue-and-groove color steel plate for wall surface and roof, and neutral silicone sealants is used for plate joints to ensure seamless; The installation verticality deviation of color steel plate is ≤2mm/m, and the flatness deviation is ≤3mm/m to avoid uneven dust accumulation. The floor adopts epoxy resin self-leveling or PVC anti-static floor. During construction, the floor shall be smooth, clean and crack-free, with a gradient of 1%-2% towards the floor drain, which is convenient for cleaning and drainage.

Sealing between doors and windows and holes: the levelness and verticality of clean doors and windows should be corrected, and sealant should be applied after the joint between door frame and wall is filled with foaming agent; The transfer window, air shower room and other openings should be seamlessly connected with the enclosure structure, and the tightness should be tested after installation to prevent air leakage.

Concealed engineering treatment: water, electricity, heating and ventilation pipelines need to be embedded or concealed, and sleeves should be installed at the wall plate and sealed; The air duct is made of galvanized steel plate or stainless steel plate, and the joint is sealed with sealant. The inner wall of the air duct should be clean and free of oil pollution, and air leakage test should be conducted before installation.

Purification system installation: accurate control of core components

Installation of HEPA/ULPA: Before installation, it is necessary to remove the outer packaging, check whether the filter material is damaged, and it is forbidden to touch the filter surface with bare hands; When installing, ensure that the gasket between the filter and the frame is pressed tightly. Negative pressure method can be used to test the tightness to avoid unfiltered air from infiltrating into the clean area.

Installation of air conditioning and ventilation system: fan coil units and air conditioning units need to be equipped with shock absorbing pads to reduce dust generated by vibration; The air outlet of the air duct needs to be equipped with a high-efficiency filter, and the air flow organization follows the principle of "sending up and returning down" to avoid the dead angle of air flow; Pressure difference sensor and temperature and humidity controller need to be calibrated accurately to ensure that the pressure difference between clean area and unclean area is maintained at 10-20Pa.

Installation of electrical and automatic control system: the electrical circuit is laid in the dark through the pipe, and the dustproof and moisture-proof explosion-proof distribution box is selected; The automatic control system needs to be linked with fans, filters and disinfection equipment to realize automatic adjustment of pressure difference, temperature and humidity, and at the same time set up emergency power supply to ensure the short-term operation of key equipment during power failure.

Pollution prevention and control in construction process: details determine cleanliness

Dust control: operations such as cutting color steel plates and drilling holes should be carried out in temporary isolation areas, and wet operations should be adopted to reduce dust; Every day after the construction, wipe the wall and floor with a dust-free cloth, and clean the dust with a vacuum cleaner. It is forbidden to use a common broom to clean.

Personnel operation specification: construction personnel are not allowed to eat, drink or smoke in the clean area, and are not allowed to carry dust-producing articles such as mobile phones and keys; When entering the clean area, you need to change clothes and air shower according to the process, and the construction tools should be brought in after wiping and disinfection.

Cross-construction management: reasonably arrange the working procedures, first complete the envelope and concealed works, then install the purification equipment, and finally carry out the ground and decoration construction; Different types of work should be staggered to avoid mutual interference and pollution.

Acceptance and debugging: comprehensive inspection to ensure compliance.

System debugging: firstly, carry out single-machine debugging to check the running status of fans, filters and disinfection equipment; Then carry out linkage debugging to test the pressure difference stability, temperature and humidity control accuracy and cleanliness of the system.

Third-party testing: Invite qualified testing institutions to test the number of dust particles, the number of settling bacteria/planktonic bacteria, the number of air changes and other indicators according to the specifications, and issue testing reports to ensure that they meet the design requirements.

Data archiving: organize construction drawings, material inspection reports, commissioning records, inspection reports and other data, and archive them for retention, so as to provide a basis for later maintenance and annual inspection.

Post-maintenance reservation: convenient for long-term stable operation.

Maintenance space should be reserved for high-efficiency filters, tuyeres and other components; Air ducts and water pipes are provided with access ports, which are convenient for operation.

Clean passages are reserved on the ground and wall surface to avoid blocking the clean area by placing equipment; Clean water-sealed floor drain is selected to prevent odor and bacteria from flowing backwards.