There is a difference between the price of a part and the cost of the part – quality. Macfab’s focus on providing a low total cost of ownership is added through our leak testing of a prototype. Leak testing is a form of Non-destructive Testing (NDT). This form of testing allows validation of the part and process while not requiring it to be a sacrificial (scrap) part. Using our Agilent vacuum and leak detectors combined with our innovative custom testing systems, your parts will arrive as expected.
As a supply chain partner, focusing on mutual success, Macfab conducts leak testing on all prototype type parts that require it. If a crack or hole is found, we careful review our internal process and retest the part. Our engineering team has developed fixturing to allow our testing to be done in both static (stationary) and dynamic (moving) conditions painting a more realistic
As a part moves into production, so too does our leak testing. The focus remains to identify defects that can only be found using this testing method. Our engineering and quality teams develop sampling plans based on consistency of the process and experience, to conduct periodic inspection of the parts validating the process remains in control. A stable process generates steady a flow of products to our customers.
Macfab practices these leak testing methods in order of sensitivity: Air Pressure (Vacuum) Decay, Bubble Immersion, and Helium Mass Spectrometry. Air Pressure (Vacuum) Decay utilizes air at a vacuum up to 80 pounds per square inch (PSI). This process reduces the variation caused by temperature, has a higher throughput compared to other methods, and can detect multiple defects if present.
The Bubble Immersion method is used to test welds and sealing of assemblies. The test piece can be pressurized at 3 to 40 PSI with a maximum of 125 PSI and submerged in a tank of water. The inspector then looks for bubbles indicating a defect.
Finally, at nearly double the sensitivity of the bubble test method is Helium Mass Spectrometry 100x to 1,000,000x. This method requires being able to develop a negative pressure difference between the test part and the atmosphere. Using this method, a quantitative measurement volume of cubic centimeters per second (atm cc/sec) of the leak rate can be recorded. Depending on the configuration of the part/assembly, the precision with which this testing is done, the location of the leak(s) can often be identified on the part.
While no process is error-free, our investment in multiple methods and a range of sensitivities provides us with options to meet a customer’s range of expectations from engineering specifications, quality verifications, and supply chain requirements. Let’s discuss the option best suited for your part and the total cost of ownership.