Leak Testing and Product Design
We have all heard the expression “if it ain’t broke don’t fix it” and it seems that as we get older it’s wisdom gets stronger and we look back to the good old days when things were simpler, even in leak testing.
Of course every generation has its good old days, mine might include microwaves or wi-fi or something else that previous generations would not have seen coming. But change is important to improve the living conditions and quality of life of our human race.
One of the most important activities that affects the life of millions is the development of new medical devices, or the implementation of improvement in existing ones.
Changing an existing product slightly is a good way to extend its life-cycle. A few well placed tweaks her and there and the job’s done, right? Well, no, not where leak testing is concerned. Even the most innocuous change can make dramatic differences. Consider three examples:
Changing the shape.
Changing the shape of a device dramatically will obviously affect the leak test. You’ll need new fixtures and maybe even a different type of leak tester. Other, smaller changes may not have a dramatic visual effect but will necessitate a test program change. For example, replacing square corners with rounded corners will change the part volume and this in turn will change the leak rate and require that a new program is created. The new program will require validation. Documents will need to be updated, approvals sought and so it goes on.
Changing the material.
Material properties differ from one to another. Replacing one material with another, say for reasons of economy, might seem like a good idea. But what if the new material has greater or lesser elasticity? What might that do to the leak rate result? Do you think you might get “false leaks” as a result of greater elasticity? You bet you would.
What about heat transfer? Leak testers are sensitive to changes in pressure. Changes in pressure can be brought about by changes in temperature. Better write another program for that.
Changing the color
Yes, really. Color changes will change the way a product deals with heat. Different colors affect how heat is dissipated, how it is absorbed or reflected. Better adjust the program for that too while you’re at it..
Unfortunately, unless you are well versed in leak testing, the effects of the above examples are all too easily underestimated or overlooked entirely. Rectifying matters then becomes a matter of utmost urgency. But, thankfully it doesn’t have to be that way.
With a little forethought and a healthy sense of curiosity a lot of frustration and extra work can be avoided. I advocate that before any changes are implemented, a step is incorporated into the development plan, near the beginning labeled, simply, “Leak Test?” that states contact leak tester manufacturer for advice before making product changes!
At Uson we like to think we are your trusted partner when it comes to leak testing. We have so much experience that can make life easier for you, please allow us to share it when you need it, even if you think you don’t.
Wishing all our customers, vendors, and friends a safe and healthy New Year 2021. Here’s to better days ahead, Joe.