China Suppliers Factory Stainless Steel Clean Laminar Flow Hood for High Cleanliness Applications
Widely used in electronics, biology, medicine, food, precision instruments and other industries of dust-free aseptic operating environment. Provides local high cleanliness working environment.
Material: Typically made of sprayed cold-rolled steel plate or stainless steel (SUS304, SUS316), known for high strength, corrosion resistance, and ease of cleaning.
Design: Corners often feature rounded transitions to avoid dead angles, facilitating cleaning and preventing dust accumulation.
Function: The "heart" of the laminar flow cabinet, providing the power for air circulation.
Location: Typically located at the top of the unit (fan on top, referred to as a "top-mounted fan" structure).
Fan: Usually employs high-efficiency, low-noise backward-curved centrifugal fans, capable of providing stable and adequate static pressure and airflow.
Motor: Drives the fan operation. Often an EC Motor (Electronically Commutated Motor), enabling stepless speed control, offering energy savings and precise control.
This is the most critical part, determining the cleanliness effectiveness.
Pre-filter (Primary Filter)
Location: Positioned near the fan intake.
Function: Filters larger airborne particles (e.g., dust, fibers) to protect the subsequent HEPA filter and extend its service life.
Material: Typically non-woven fabric or nylon mesh, which can be washed or replaced.
HEPA Filter (High-Efficiency Particulate Air Filter)
Location: Located at the bottom of the enclosure, facing the work area directly.
Function: The key guarantee for cleanliness level. Filters out particles ≥0.3µm with an efficiency of up to 99.99% (for 0.3µm particles). Ensures the discharged air is clean and sterile.
Installation: Requires specialized sealing structures (e.g., liquid trough seal, mechanical clamping with gaskets) to ensure no leakage.
ULPA Filter (Ultra-Low Penetration Air Filter)
Location: Same as the HEPA filter.
Function: Used for applications requiring higher standards, with a filtration efficiency of ≥99.999% for particles ≥0.12µm.
Function: Located above the HEPA filter, it ensures air is evenly distributed before passing through the filter, thereby creating a uniform and stable vertical laminar airflow at the air outlet.
| Filter Type | Particle Size | Filtration Efficiency | Typical Application |
|---|---|---|---|
| HEPA | ≥ 0.3 μm | ≥ 99.97% | General cleanroom, electronics, pharma |
| ULPA Higher Grade | 0.1 – 0.2 μm | ≥ 99.999% | Semiconductors, biosafety laboratories |
As dust accumulates on the filter media, the resistance increases. When the resistance reaches an unreasonable level, the filter must be discarded. Sometimes, excessive resistance can cause previously captured dust to become dislodged and re-enter the airflow; when this risk arises, the filter should also be replaced.
The resistance of a filter increases with higher airflow rates. By increasing the surface area of the filter media, the relative velocity of air passing through the filter can be reduced, thereby decreasing the resistance.
Remarks: (1) Initial resistance tolerance of ± 10% (2) Support customer size