1. Turbulent flow: Air enters the clean room through the air conditioning unit, air ducts, and air filters in the clean room, and is returned by the partition wall panels or elevated floors on both sides of the clean room. The airflow moves non linearly and exhibits irregular turbulence or eddies. This type is suitable for cleanroom grades 1000-100000.

Advantages: Simple structure, low system formation cost, relatively simple expansion of clean rooms, and in some special use areas, dust-free workstations can be used to improve the level of clean rooms.

Defect: Fine dust particles formed by turbulent flow float in indoor spaces and are difficult to discharge, which can easily contaminate manufactured products. In addition, if the system terminates the task and reactivates it, it often takes an appropriate amount of time to reach the required cleanliness level.

2. Laminar flow: The laminar airflow moves in a uniform straight line, and the air enters the room through a filter with a coverage rate of 100%, and is returned by the elevated floor or two side partition boards. This type is suitable for environments with high requirements for cleanroom levels, generally ranging from 1 to 100 cleanroom levels. It can be divided into two types:

(1) Horizontal laminar flow type: Horizontal air is blown out in one direction from the filter and returned by the return air system on the opposite wall. Dust is discharged outdoors with the wind, and pollution is generally severe on the lower side.

Advantages: Simple structure, can become stable in a short period of time after homework.

Defects: The construction cost is higher than that of turbulent flow, and the indoor space is not easy to expand.

(2) Straight laminar flow type: The ceiling of the room is completely covered by ULPA filters, and the air is blown from top to bottom to achieve high cleanliness. Dust generated during the process or by workers can be quickly discharged outside without affecting other work areas.

Advantages: Simple management, stable operation can be achieved within a short period of time, and is not easily affected by the operation status or personnel.

Defects: The structural cost is high, the flexible use space is difficult, the ceiling hanger takes up space appropriately, and repairing and replacing the filter is more complicated.

3. Composite type: Composite type combines or combines turbulent flow and laminar flow, providing partially ultra clean air.

(1) Clean and authentic: Covering the process or work area with HEPA or ULPA filters to 100% increase the cleanliness level to level 10 or above, which can save installation costs. This type requires isolating the work area of the operators from the product and machine repairs to prevent any impact on the work and quality during machine repairs. This type is commonly used in ULSI processes. There are two advantages to a clean tunnel:

A. Elastic expansion is simple;

B. It can be easily performed in the repair area when repairing equipment.

(2) Clean pipeline: Enclose and purify the automatic production line through which the product process passes, and raise the cleanliness level to above level 100. Due to the isolation of products, operators, and dust generating environments, a small amount of air supply can achieve good cleanliness, saving energy. Automated production lines that do not require manual labor are more suitable for use. Applicable to the pharmaceutical, food, and semiconductor industries.

(3) Install some clean rooms: increase the cleanliness level of the product process area in the turbulent flow clean room with a cleanroom grade of 1000-100000 to above 10-1000 for production purposes; Clean workstations, clean work sheds, and clean air cabinets belong to this category.

Clean workbench: Level 1-100.

Clean working shed: To enclose a small space with anti-static transparent plastic cloth in a turbulent flow clean room space, independent HEPA or ULPA and air conditioning fan units are selected to become a higher-level clean space, with a level of 10-1000, a height of about 2.5 meters, a coverage area of about 10m2 or less, four pillars and movable wheels, which can be flexibly used.

The article originates from Guangdong Purification Engineering: http://www.jmyujie.com/