Leak Testing

Non Destructive Examination (NDE)

Non Destructive Examination is the act of  evaluating a welded component (or material to be welded) without affecting the serviceability of the part or material

  • All Welds have flaws.
  • Another name for a flaw is a discontinuity
  • Discontinuities are interruptions in the normal crystalline structure (or grain) of the metal.
  • Discontinuities are NOT always defects
  • The purpose of welding inspections is to locate and determine the size of any discontinuities
  • Discontinuities that are to large or repeat too often within the weld become defects
  • Defects will compromise the welds overall strength

What are some common defects

  • Porosity
  • Undercutting
  • Rollover or “Cold Lap”
  • Slag inclusion
  • Poor penetration
  • Voids
  • Hydrogen Embrittlement

What is Leak Testing?

Leak testing is a process used to detect manufacturing defects which helps verify the integrity of products and improve consumer safety.

For example, the automotive industry consistently uses leak testing to verify that assembly operations were completed properly and subcomponents are leak free.

These leak testing procedures are defined and specified by a variety of standard organizations.

For the automotive industry, these include requirements from the American Society for Testing and Materials (ASTM) and the Society of Automotive Engineers (SAE), as well as, many OEM internal specifications.

Manufacturers that produce parts that contain gas or liquid, need to know if their products include any defects that could allow leakage.

Defective products can be costly due to increased warranty claims and potentially endangering consumer safety.

A main component of many leak testing methods is the concept of leak flow, which refers to the leakage of a gas or liquid from the product.

There are several methods available for leak testing a product. The most appropriate test method for each application depends on several items:

  1. Purpose of the testing (criticality to detect defect)
  2. Leak rate specification (very crucial parameter that can direct a test method alone)
  3. Test cycle time (production cell test time)

We offers our patented Micro Flow Technology for leak testing.

This method is based on the mass conservation law.

The Intelligent Gas Leak Sensor, or IGLS, inside the leak test instrument will measure the flow rate of gas entering the test part (unit under test, UUT) from a reservoir as gas is leaking out of the UUT.

The incoming flow rate at a steady state condition is equal to the amount of mass leaking out.

This allows the leak tester to directly measure leaks with better accuracy and faster cycle times than other air leak test methods.

Each product/application may have its own distinct process parameters.

We can provide the tools to help implement a leak testing program, from defining your leak specification to designing and building a custom test system.

 

Leave a Reply

Your email address will not be published.