By Jack Sun · Filtalloy
Compare pressure drop at the target flow after aligning the test fluid, element state and pressure tap locations. A close estimate is useful for screening; verify a borderline result at the actual acceptance point.
Where were the pressure taps?
A media coupon measures the specimen within a defined fixture. A finished element may include fitting and fixture losses. An assembly can include housing and connection losses between its pressure taps. ISO 4022:2018 covers applicable permeable sintered metal materials. ISO 4022
When two curves can be compared
Check fluid, temperature, flow direction, instrument and measurement boundary. For gas, confirm whether volumetric flow is actual or referenced to stated conditions. Keep clean, loaded and cleaned conditions separate. Match viscosity and assembly conditions where they affect the comparison.
Example at 25 L/min
| Flow (L/min) | A (kPa) | B (kPa) |
|---|---|---|
| 10 | 4 | 5 |
| 20 | 9 | 12 |
| 30 | 15 | 20 |
With a hypothetical 15 kPa limit, linear interpolation between 20 and 30 L/min gives 12 kPa for A and 16 kPa for B. Confirm the result at 25 L/min before acceptance. If the target changes to 35 L/min, obtain another measurement. Measured flow and pressure drop calculator
Write the acceptance point
Specify the clean element and housing, medium, temperature, direction, pressure taps, actual target flow, flow tolerance, stabilized reading criterion and allowable pressure drop. For equipment with several operating points, agree which points need verification.
Frequently asked questions
Do lower readings prove better filtration?
Compare retention and integrity separately. Pressure drop describes flow resistance at the stated conditions.
What if the curves cross?
Check each critical operating point against its limit before comparing margins at the usual operating flow.
Powder-sintered porous metal products · How sintered powder filters work
Jack Sun has long worked in metal wire mesh weaving and industrial filter-element manufacturing. Filtalloy is based in Anping, Hengshui, Hebei, China.
