The Pioneer of Modern Leak Testing

Five Step Leak Test

What is a Five Step Leak Test?

The five step leak test is manufactured exclusively by USON for fast-flush drug delivery device testing. Fast-flush devices are commonly included in many disposable medical procedure kits and pre-packaged drug delivery systems. For this test, the tester must be able to control a complex testing routing of a pressure sensor, two precision mass flow transducers, valves and logic control.

How does the Five Step test work?

Below are the steps required to perform the Five Step leak test:The product is attached to both test ports.

  1. Air is routed to both Port 1 and Port 2 to conduct a leak test on the product body.
  2. Air is routed to Port 1 through the restrictor and out to atmosphere through valve V2. Low flow is measured with the low-range flow transducer (F1).
  3. The product’s flush valve (FF) is activated by the operator or automated fixture. The resulting high low is measured with the high-range flow transducer (F2)
  4. A second low-flow test is performed.
  5. A comparison is made of the first low flow to the second low flow to make sure the flush valve (FF) has properly reseated in the device being tested.
Five Step Test Pneumatic Diagram
Five Step Test Pneumatic Diagram

Which Uson Leak Testers Can Perform a Five Step Leak Test?

Optima vT – A versatile and customizable leak tester with up to two channels and eight sensor inputs that supports pressure decay, differential pressure, mass flow and other common tests.

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