How to test leaks

The oft debated political pros and cons of globalisation tend to grab the spotlight away from the fact of more engineers and technically trained minds on the planet now driving innovation – even though entire continents are still by and large left out.

Many aspects of process and control engineering are undergoing unprecedented rates of innovation based on scientific advances in areas like computational fluid dynamics, nanotechnology, bio-engineering.

There are also new challenges that engineering teams are being called upon to tackle globally – from needs for better fuel efficiencies to creating new potable water systems to maintaining waterproof power supplies, equipment and product functionally in the context of greater variations in climate conditions worldwide. Innovation, always a staple of engineering, proceeds at a faster pace.

Consider too that processing power continues to explode for lower and lower costs driving modelling of product improvements as a new normal.

Faster innovation on a global scale is reflected in your company's microcosm or very well should be. One aspect that is begging for new consideration is how capital equipment expenditures anticipate improvements in products and shorter time-to-market.

Manufacturing facilities equipped with instrumentation for needed quality controls and other plant designs either anticipate new products not even on the drawing board yet or they do not.

Obviously, companies that are forward thinking in capital equipment expenditures along these lines are building in long-term advantages to grab market share through innovation. 

From an engineering standpoint, it means that engineering teams (design, process, manufacturing, quality) need to be thinking about the elasticity of every capital expenditure and its real economic life if and when product designs change.

Product iterations

Using leak test technology as an example because of the wide array of applications where it comes to bear on process and control engineering outcome.

One can see leak testers being sold in the global marketplace today that range from models that are truly obsolete (even if not recognised as such), to leak detectors that are fine for testing the products at hand today, to the newer generations of leak testers that feature versatility for product iterations not yet imagined.

The real economic life of any leak detector you choose is now determined by how flexible it will be to handle leak test requirements that are not yet on your docket.

Figure 1 above illustrates how leak testers of these aforementioned categories – out-of-date vs. match for today's products only vs. designed for multi-generation products testing – stack up feature-wise. 

What defines out-of-date leak testers in their core is likely mirrored in out-of-date technology for other manufacturing automation and instrumentation. These are largely leak testers that were designed with electronic componentry, processors and data handling methods from an earlier era.

These are inflexible leak testers that have limited ranges and are usually not optimised for the application at hand. There are companies that are "penny-wise but pound-foolish" that have done nil capital equipment investments for quite some time not realising how their operation is saddled with longer test cycle times or other hidden costs of out-of-date technology.

As Figure 1 suggests, current technology has far more sophisticated programming capabilities that can handle more complexity in testing and data storage. Modern leak testers were born in the age of globalisation and feature more intuitive graphical displays that allow more lightly skilled workers to operate the test technology.

Today's testers can handle a wider range of test specifications – parts volumes and pressures for example.

However, if you are sourcing a new leak test instrument, an important lens to view the technology through is how adaptable it will be for new product innovations. The newest models of leak testers – like other instruments or aspects of automated systems – are notable first and foremost for their flexibility.

In terms of leak testers, they have multiple sensors or multiple test channels or both – such that there are possibilities to speed production with either synchronous or independent testing of multiple parts of components of parts.

These leak testers are also distinguished by their fully customisable pneumatics and flexibility for I/O programming. Like other future-focused capital equipment, they handle a good deal of complexity automatically so that they are simple to operate.

Totally configurable

In the case of future-focused versatile leak testers, they are distinguished by their ability to handle virtually any combination of leak, flow, burst, occlusion and other NDT tests of that nature.

They include sensors that can be re-tuned to new product specifications in the future. Their pneumatics are totally configurable and reconfigurable. They handle orders of magnitude greater test data results and/or test steps complexity.

There are some inherent markers that will help you discern more future-focused capital equipment investments from those that are more fixed to the strict specifications of today.

First word to the wise is to make sure that the product is supported cradle to grave, including support for reconfiguring the instrument or other equipment for future applications.

With leak testers, there are actually many manufacturers that provide absolutely no support once a leak tester is sold. Others will assist with an initial installation but then leave it at that. If you are future-focused on capital equipment uses, the value of long-term support should be clear.

Another lens to view potential capital equipment through is its versatility and the relative ease or difficulty of reconfiguring the equipment or instrument in the future.

Pneumatics are an essential element of leak test systems and for optimum efficiency they need to be tuned to your specific application specifications – for example, parts volume, test pressures.

But if you take it as a given that your continuing innovation will inevitably change these physical parameters, you need to ask how easily your leak tester's pneumatics can be reconfigured.

For any instrument or capital equipment expenditure there are comparable aspects that are essential to function and are either designed for reconfiguration or are fixed.

This is not to say that there are not leak testers that are not flexible for the future that are nonetheless very high-end instrumentation and equipment for today's applications.

There are companies that sell many of these best-in-class leak testers tuned to specific application requirements. In some cases this is still preferred and the data handling, programming capabilities are more than adequate for the NDT tests required. 

Sometimes however, we find that even within the constraints and specification of the current test application, leak testers with greater upfront costs are not given their fair due.

For example, a leak tester that can do eight simultaneous leak tests can have much lower overall testing costs than a leak tester with a more limited number of sensors and/or channels.

It's rarely complicated to do the math to make the determination on returns-on-investments for today's application. Moreover, with a long range view in mind that anticipates new test methods being required you know that the lifetime return-on-investment is greater still, although admittedly not lending itself to simple "do the math" type calculations. 

The extent to which a leak tester (or any instrument or piece of equipment used in a production line) is programmable is also a rough marker of how well suited it will be to handle future product iterations. When there are greater I/O capabilities built in, it suggests an inherent ability to handle testing complexity.

In the case of leak testers it may mean that the firmware in the leak test instrument has more programmable steps, possibly hard-wired to jump to another test step or an entirely different program for greater flexibility.

More I/O flexibility in future-matched leak testers (i.e. 32/122 as shown in Figure 1) means that your operations will be able to change sequences in tests based on the results of a prior step. This greater ability to program I/O is an ideal match for future scenarios that are currently unknown in their specificity. 

What we see anecdotally is that the companies that are most proactive in R&D for new product developments are employing the more flexible leak test technology for product development today.

Being able to try different test scenarios helps ensure that the optimum settings and configuration of the leak detector are defined when the product rolls out.

This is especially important to the many companies that are not only eager to make time-to-market as quick as possible but who plan to then produce products in globally distributed manufacturing facilities. 

Materials innovations

In summary, today's valves, waterproof power supplies, heat exchangers, equipment operating in pressurized conditions and all other products with strict leak rate specifications are very likely to change in significant ways within the decade.

New materials innovations such as composites, nanotechnology, ongoing market feedback on better feature design or additional features to enhance usability are just some product innovation drivers we can count on.

The shorter your company's time-to-market for product innovations the greater your ability to garner market share. Similarly, the ease with which you can establish consistent quality with globally distributed manufacturing will impact your company's ability to gain footholds in new terrain. 

There is a wide array of leak detection systems available today. The real economic life of any leak detector you choose is now determined by how flexible it will be to handle leak test requirements that are not yet on your docket. Leak testers are no different from other capital expenditures for manufacturing.

The fork in the road is whether to choose application specific testers for today's needs or those that offer future flexibility built in.

Don't just think about today's solution – think about tomorrow too and insist that your suppliers demonstrate technology with future requirements in mind and a support model that will be by your side when the inevitable changes in your production line designs and processes need to be made.

[Dave Foran is President of USON.]