Selection criteria for Leak Testing Method & Equipment

What are the important aspects to be considered in Leak Testing?

The important aspects that need to be kept into consideration in the selection of leak testing methods & equipment in manufacturing to name a few include leakage rate, cycle time, design & sensitivity. Various technologies are available for leak testing and it is critical to select one which is optimal to your application requirements. In our previous blog titled Benefits of Leakage testing, we have discussed different types of leak testing methods.

The following factors should be considered when it comes to choosing a suitable Leak Testing Method.

  • Decide Leakage rate that need to be detected. 
  • Sensitivity must be considered too. Highly sensitive helium leak detection is the best way of detecting leak tightness in the range of 1 x 10 –7 mbar*l/s or lower, but if your required leak rate is above this value, then one can go for air leak detection.In applications where high levels of sensitivity are required (e.g., medical products where leaks can cause a risk of contamination) or which have stringent water ingress or safety specifications including semiconductor tool applications, airbag activators & aerospace parts etc., the only option is helium leak detection. However, in most applications such as heat exchangers, brake systems, welded assemblies, electronic enclosures etc., both air and helium test methods can be used.
  • Select the test media fluid to be used for testing e.g., Air, Water, Helium gas, Nitrogen, Oil etc.
  • Leak test methods can also be affected by environmental conditions. As an example, let’s look at pressure decay testing which relies on stabilization times as well as temperature control to get reliable, accurate measurements.   These requirements make it unsuitable for leak testing in a few different environments, e.g., when items are very hot (e.g., a part that has just been welded) or when there are rapid and extreme temperature swings.  In these circumstances, vacuum air testing or helium testing are preferable to pressure tests.

The following factors should be considered when it comes to choosing Leak Testing Equipment.

  • The design of the part under test & specifically the design of the fixture, seals – should also be considered. Some seals will perform better under higher pressure and vacuum than others.
  • Study cycle/throughput times If your application involves testing of 100% of components or parts in a production line, then speed is an important consideration.  If your leak testing challenge is limited to sample testing and laboratory applications, then throughput times aren’t such a critical factor in your choice of leak testing technology.
  • Choose acceptance & Rejection criteria– Leak testing often subjected to vacuum or a part to its maximum operating or Factor of Safety (FOS) pressure. In some cases, it also reaches to burst pressure where in destructive testing are carried out.
  • Mode of operation– Based on accuracy, productivity & daily usage required you need to select system operation to be Manual, semi-automatic or fully automatic. Now a days IOT, Industry 4.0 etc. is being adapted for faster, accurate & traceability point of view.
  • Reliability & importance of test- Choosing accuracy of test system, accurate setup will cost more & lesser accurate setup will cost less. Being a Capex equipment ROI or payback period, depreciation, life of product required, ownership, maintenance, importance for QC / QA etc is prime important points for any investor or company management.
  • Safety-The most important point. High pressure, flow, temperature is not easy to handle when it comes to having setup in manufacturing plant. This is big topic. But to summarize, importantly following safety areas could be segmented.
  • Structural integrity & safe design of test hood.
  • Functional safety incorporates of instruments & part used in system like valves, tube/pipe, hose, transmitters, sensors, electrical & electronic instruments etc.
  • Operator safety. Use of interlock & effective use of industrial engineering practices.

Choosing the right leak testing method & building the right equipment is critically important & it all starts with your choice of equipment builder. They need an extremely high level of expertise, competencies & also need to understand your requirements. For knowledgeable advice, top-quality equipment & a genuine desire to provide a reliable, innovative and flexible solution connect with A B Process Technologies, Pune.

Author: admin

Leave a Reply

Your email address will not be published. Required fields are marked *