After the FFU design air volume is determined, how should the static pressure be matched?
Direct answer: After determining the FFU design air volume, you should check the performance of the fan at this air volume instead of taking the maximum static pressure in the product data. Check the resistance of the specified filter and installation system under the air volume with the air supply capacity of the corresponding working point of the FFU; then confirm the actual air volume through a prototype or on-site test.
'Design air volume' is the air supply volume that the project hopes FFU will provide under normal operating conditions. It is different from the maximum air volume obtained by the product under certain test conditions. When selecting, first determine what the project requires, and then make a judgmentWhether the FFU fan filter unit can continue to meet the requirements in actual working conditions.
Where does design style come from?
Clean room projects should determine the air supply needs of each area based on process cleanliness goals, air supply range, dust generation from personnel and equipment, target wind speed and air flow organization, and then allocate them to a single FFU. Equipment-side projects should also consider internal equipment space, opening locations, and return air paths.
If the project sets different working gears at the same time, the target air volume for production and duty status should be separately stated. The highest nominal air volume cannot be used to represent all operating conditions.
Static pressure calibration looks at the same working point
The FFU air volume and the resistance to be overcome jointly determine the operating point. After determining the design air volume, you should ask the supplier for the performance data at the corresponding gear and clarify the test location and meaning of the static pressure data.
The project shouldThe resistance, box and related installation conditions of the HEPA or ULPA filter under the design air volume are included in the verification. If the supplier provides performance data of the entire machine with a filter installed , it must also be clear whether the data includes filter resistance to avoid double counting.
'Maximum air volume' and 'Maximum static pressure' may appear in different operating states respectively. Writing the two directly into the same design condition will overestimate the actual air supply capacity of the FFU.
New filter qualified, operational changes also need to be considered
The initial resistance of the filter is only the starting point for selection. After operation, the resistance may increase, and the actual air volume of the fixed-speed FFU may decrease. Using a speed-adjusting solution to maintain the air volume may increase the operating gear and power consumption. The project should agree on resistance monitoring, air volume review and maintenance conditions to confirm that the designed air volume can be maintained during the normal operating cycle.
If the filter efficiency level or model changes, the fan operating point should be rechecked. The filtration efficiency meets the process requirements, but it does not mean that the replaced FFU can still reach the original design air volume.
Write the verification results into testable requirements
It is recommended to specify the design air volume, filter configuration, operating gear, static pressure or resistance measurement location, test method and allowable deviation in the technical agreement. Prototype testing should be carried out according to these conditions; after batch installation, on-site air volume, wind speed uniformity and cleanliness should be checked.
Aili Industrial can match the fan, motor, filter and box structure based on the design air volume, filtration requirements, ceiling or equipment installation dimensions and control requirements. After the project provides clear working conditions and test requirements, it is easier to confirm single unit specifications and batch configuration. Specific performance is subject to technical protocols and actual test results.
