Leak Detection System

Why is leak detection important for your vacuum system?

January 27, 2023


The importance of leak detection for your vacuum system

If you have a vacuum system, you need a helium leak detector. You spend a lot of money on vacuum pumps, piping, hardware, and gauges, but if you have a leak, your system ends up not working effectively and you're throwing away money. Leak detection is an important step that you should not skip during your vacuum system application. Leak detection is crucial to make sure your system is working effectively and performs to its fullest potential. Keep reading to learn more about leak detection, the different types of leak detector cart systems Leybold offers, and why it's crucial to your application!

Why would you detect leaks in your vacuum system?

  1. Protection for personnel and environment
    • Leaks in overpressure equipment or systems can lead to contamination of the environment with harmful substances (toxic liquids or gases).
  2. Assurance of product quality
    • A product can be negatively impacted in terms of quality and reliability by material loss or penetration of foreign substance or gas by exceeding pass/fail design criteria.
  3. Maintenance and operational readiness of machines or manufacturing systems
    • Unacceptable leak rates endanger the operational readiness or even the safety of machines and systems, reduce their effectiveness, disrupt process flow, and leads to defective end product.


The four most important leak detection questions

How can I find out if I have a leak in my vacuum system?

There are multiple methods utilized to detect leaks, we recommend you to use a helium leak detector and isolate the system into small parts making sure each section is leak tight to your specification. The key is to reduce the flow of the helium tracer gas to make sure you pin point and repair any leaks in each individual section tested. Eventually, you’ll be able to isolate the vacuum system from the installation and by a process of elimination you’ll be able to find the source of the leak.

Where is the leak?

To discover where your leak is located, you can use a helium leak detector and helium as a tracer gas. The key is to use the least amount of helium during the leak test and start at the highest point away from your vacuum pumps. If the system is using vacuum, use the integral method (outside in). If it’s used for positive pressure, use the over pressure method and sniff (inside out).

How big is the leak?

If installed directly to your vacuum system (no external vacuum pumps), the helium leak detector will display the actual measured value of your leak (mbar l/s, atm cc/s, etc). There are several calculations that can be done that can convert the actual displayed value of the leak rate into an actual whole size. If you using external vacuum pumps and parallel with a helium leak detector remember the actual leak rate is higher than the displayed value due to the split flow ratio of the amount of helium going to the leak detector compared to the external backing pumps (split flow principal).

Can the leak be eliminated?

A leak can’t be eliminated completely. There is no such thing as 100% leak tightness, everything leaks at some value. However, how much is leak is a relative term and is a function of your system and application. The acceptable leak rate for your specific system should be determined by the required vacuum level of your vacuum system. Once the actual vacuum level of your system has been determined you can easily established your specific pass/fail leak criteria for your system and/or application.

Leybold leak detector cart system

Leybold's leak detector carts are a great mobile solution to make sure your system or manufacturing process is operating with an acceptable leak rate. This gives you the top performance of your system or manufacturing process by efficiently detecting leaks that are hurting your business and costing you money. 

Leybold offers stand-alone portable leak detectors: The PHOENIX Quadro Wet/DRY and PHOENIX Vario . You can use these leak detectors to check on anything you'd like, and they perform extremely well without extra backing pumps up to a certain size volume. When you leak test larger volumes, you must consider using external backing pumps in the split flow arrangement or using a leak detector with a separate backing pump mounted on a cart. This is where the leak detector cart comes in and saves the day!

The mobile leak detector cart systems allow you to leak test larger volumes faster and more effectively. They include the option to install a helium bottle to the back of the cart for a turn-key mobile leak detector station.


How does a leak detector work?

The PHOENIX Vario (leak detector without an internal pump) mounts on top of the cart, and the required external backing pump is installed on the bottom. This gives major flexibility, as it becomes a mobile leak detector solution for leak testing larger volumes quickly. This solution reduces evacuation time, reduces helium background, and improves sensitivity.


It's also possible to put a PHOENIX Quadro (Wet or Dry) and a partial flow system on top of the cart, along with a large backing pump on the bottom.  This gives you the ability to quickly leak test larger volumes all the way up to ATM.


The Leybold leak detector cart systems are supplied with standard 6-inch wheels, but you have the option to add 12-inch heavy industrial wheels or suitable wheels for clean room applications (anti-static and non-marking).

Additionally, the Leybold leak detector cart systems are delivered fully assembled and tested, making it a very simple turn-key solution to install.

Applications of leak detectors

There are different situations where one leak detector cart would work better than the other.

A good rule of thumb is that the standalone PHOENIX Quadro (Wet/Dry) can be used very efficiently for chamber volumes less than 10 liters. If you're leak testing a system greater than 10 liters, it's highly recommended to use a mobile leak detector system with an external backing pump mounted below or external backing pumps in a split flow type arrangement.. This will reduce the time for evacuation, helium cleanup, and helium background and increase sensitivity while protecting the cleanliness of the internal valve block of the leak detector.

The PHOENIX and mobile leak detector system are very robust and reliable, but they do require annual maintenance (oil changes, filters, etc.) based on usage.

The PHOENIX Vario mobile leak detector cart system with a dry external backing pump is very robust and reliable. These carts don’t require as much annual maintenance (no oil or oil filter changes, etc.), so you won’t have to deal with the disposal of used oil.

The following is a list of the standard Leybold mobile leak detector cart systems:

  • PHOENIX Quadro Wet, Cart, 115V, Standard Wheels
  • PHOENIX Quadro Dry, Cart, 115V, Standard Wheels
  • PHOENIX Vario Cart, 115V, Standard Wheels
  • PHOENIX Vario-TRIVAC D 16 B, Cart, 115V, Standard Wheels
  • PHOENIX Vario- SCROLLVAC 15 plus, Cart, 115V, Standard Wheels
  • PHOENIX Vario-ECODRY 25 plus, Cart, 115V, Standard Wheels
  • PHOENIX Vario-ECODRY 35 plus, Cart, 115V, Standard Wheels
  • PHOENIX Vario-ECODRY 65 plus, Cart, 115V, Standard Wheels
  • PHOENIX Quadro Wet, Cart, 115V, Partial Flow System, TRIVAC D 16 B
  • PHOENIX Quadro Dry, Cart, 115V, Partial Flow System, SCROLLVAC 15 plus
  • PHOENIX Quadro Dry, Cart, 115V, Partial Flow System, ECODRY 25 plus

If you are interested in a Leybold PHOENIX mobile leak detector system, contact an Inside Sales Engineer here!

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