Control temperature for a better mass flow or pressure decay leak test

April 7, 2020 | By Chuck Hagyard Sr. Business Development Manager
When implementing a mass flow or pressure decay leak test in a production environment, there is one thing that will dominate above all else and be your greatest source of problems—the management of temperature-related issues.

Ideal Gas Law: The importance of temperature 

The key to understanding temperature is understanding the ideal gas law; the PV = nRT formula, where P and V are the pressure and volume, n is the number of moles of gas and R is the ideal gas constant. For our purposes, the key variable is T (temperature). 

The first step in managing temperature is understanding its influence. So, if you understand the formula and you understand that temperature is the key element in that equation, then you are on the right track for an effective test.

How to prevent temperature variations in your leak test

When you are faced with problems caused by temperature variations, there are different sensor-based tools and algorithms that you can use to manage this. However, the best way to ensure an effective test is to take the steps required to avoid the temperature variations in the first place. You can do this by managing your production process and your production environment to minimize the influence of temperature as much as possible. 

Control the production process

For example, don’t calibrate the leak test instrument with a part at an ambient temperature when production parts will consistently be arriving at the test stand at an elevated temperature thanks to a previous production process. That’s a prescription for a lot of heartburn. 

We want to design manufacturing processes so we have a production part that is as close to the ambient temperature as possible during the leak test. Ensuring the temperature of your calibration part and your production part are as close as possible minimizes the influence of temperature.

Control the production environment

Temperature variations may also be caused by a number of factors beyond what occurred during a previous production step. Things like a door opening and closing or an HVAC system turning on or off can cause localized variances in temperature that can be significant. Seasonal variations can also play havoc in plants that lack sufficient environmental controls. 


The recipe for success is to design your manufacturing process and your production area to minimize temperature variations and fluctuations within your test environment, and between your production parts and calibration parts. 

If controlling temperature or compensating for temperature variation is a problem on your line, let’s talk about how we can help you address it.
 
 

Learn more with Ask The Experts video series 

video clip This topic was also covered as
part of our Ask The Experts video series.