By Jack Sun · Filtalloy
A passing media flow test leaves the end connections and housing seals to be verified separately. Define the tested boundary before deciding what an integrity result covers.
Where bypass can occur
Inspect the porous wall, its joint to solid ends and the installation seal between the upstream side and outlet. A temporary fixture seal can also generate a misleading indication. A designed bypass valve is a separate system feature with its own functional check.
What the tests tell you
Flow and pressure drop describe resistance between named points. Integrity testing looks for unacceptable leak paths under an agreed method. A particle challenge determines retention under specified conditions. ISO 2942:2018 applies within its hydraulic filter scope and treats first bubble point separately from filtration rating and efficiency. ISO 4003 addresses bubble-test pore size for applicable sintered materials. ISO 2942 · ISO 4003 · ISO 16889
A repeated bubble indication near the fitting
Record the original location, fixture, liquid and test conditions. Verify the fixture with the approved blank or reference and retest the original element. If a verified setup repeatedly shows the indication at the same product joint, isolate the part and investigate the connection. If it disappears after a fixture seal correction, retain the original and repeat records and apply the agreed retest rule.
Write an acceptance record
List the sample ID and drawing revision, test object, installed seals covered, fixture and instruments, fluid and test conditions, acceptance limits, observed location and final disposition. Use separate records for media, a bare element and a complete housing assembly where applicable.
Frequently asked questions
Does low pressure drop prove bypass?
Verify flow, fluid, temperature and instruments first, then use an appropriate integrity check to locate a possible leak.
Does a passing bare element verify the housing seal?
Verify the installed seal in the assembly or a fixture agreed to represent it.
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.
