5 most common types of leak testing—and when to use them

May. 06, 2024

5 most common types of leak testing—and when to use them

For those unfamiliar with leak testing on the manufacturing line, the various technologies and methodologies can seem overwhelming. How do you determine the appropriate type of leak test for your specific application? How can you ensure that the method you're using is delivering optimal results?

These are some of the questions we aim to help you answer in this blog post. Below, we delve into the most prevalent types of leak testing you may encounter on your production line, discussing the advantages and disadvantages of each for different applications.

If you want to learn more, please visit our website.

Dunk Testing

The most basic type of leak testing is submersion or dunk testing, also known as bubble testing. In this method, you pressurize the part, submerge it in water, and then look for gas bubbles. Typically, compressed air is used to conduct the test at various pressures and time intervals. The size and frequency of the bubbles indicate the size of the leak. You can also measure scientifically by submerging a graduated cylinder and collecting bubbles over a 60-second period; the amount of displaced water from the cylinder gives a volumetric flow of air per minute (mL/min).

Pros: This is a straightforward and cost-effective method for basic leak detection and location.

Cons: Visual inspection during dunk testing can be imprecise and operator-dependent. While you can estimate the leak rate based on bubble size and frequency, it does not provide exact metrics. Therefore, this method is not suitable for applications that require precise leak rate measurements.

Learn more about dunk testing >

Pressure Decay Leak Testing

Pressure decay leak testing is a widely used method where you pressurize the part or assembly, isolate the test pressure, and then measure the rate of pressure loss over time, which correlates to a known flow rate. Modern pressure decay leak testing technology enables the detection and measurement of small, non-water leak rates with high accuracy.

Pros: The test is quick and highly accurate, and it can be calibrated to a leak standard for standardized volumetric flow measurement.

Cons: This test does not pinpoint the source of leaks and may be slow for large parts with low leak rates. Additionally, testing larger parts can be time-consuming due to decreased pressure changes.

Learn more about pressure decay leak testing >

Vacuum Decay Leak Testing

Vacuum decay leak testing operates similarly to pressure decay testing. In this method, air is evacuated from the part or assembly to detect leaks. This type of testing is often used for parts that could have leaks from external sources, such as underwater sensors, pipes, or outdoor electrical housings.

Pros: Vacuum decay testing is as sensitive as pressure decay testing and offers similar precision. It is less affected by changes in environmental conditions, making it a good option for applications where temperature control is challenging.

Cons: Full vacuum pressure testing can be influenced by liquid evaporation and surface outgassing, which reduces sensitivity. This test alone is not suitable for pressures greater than 14.7 pounds per square inch (psi).

Learn more about vacuum decay leak testing >

Mass Flow Leak and Functional Flow Testing

Mass flow leak and functional flow testing involve pressurizing air into a part and measuring the rate of flow as it is maintained at a constant pressure to determine the integrity of the part or identify blockages.

Pros: This non-destructive leak test is ideal for identifying large leaks, restrictions in part channels, and blockages, such as when testing medical catheters or tubes. It is particularly useful for applications that pose challenges to manufacturers.

Cons: The sensitivity can be too low for detecting smaller leaks. The accuracy of the readings depends heavily on the flow meter's measurement range, the cleanliness of the test air, and the stability of the system's supply pressure.

This technology does not require calibration to a master part and is suitable for both laboratory use and testing on an assembly line with a large volume variance between parts.

Learn more about mass flow leak and functional flow testing >

Tracer Gas Leak Testing

For parts and systems that require extremely low leak rate detection, tracer gas leak tests such as sniff leak testing, nitrogen purge leak testing, accumulation leak testing, and hard vacuum helium mass spectrometry are used.

Pros: Tracer gas testing is unaffected by temperature or pressure changes inside the part, making it ideal for applications where parts are tested at inconsistent temperatures and low-level leak rates are required.

Cons: The test's sensitivity can be compromised by uncontrolled atmospheric trace gases that create background noise. This necessitates the use of nitrogen purge technology, testing in a sniffer booth, or employing hard vacuum mass spectrometry.

Learn more about tracer gas leak testing >

Goto Cell Instruments to know more.

Want to learn more about the basics of leak testing?

We have consolidated our decades of experience in helping manufacturers find the right leak tests into a comprehensive digital guide. Everything you need to know is included in this guide.

Download this free guide using the button below:

Water Leak Testing: A Step By Step Guide For An Accurate ...

Water leak testing involves straightforward concepts, yet they are often overlooked or not utilized properly. This article aims to provide you with a foolproof guide for an accurate leak test. Please follow each step carefully. Even then, it’s advisable to consult a professional plumber and involve the DEP for verification.

Balkan and most NYC sewer and water main contractors offer free site visits that include a complimentary leak test. Additionally, you can call 311 or use the 311 online system to request free on-site leak testing for property owners by the NYC DEP.

The Common Reasons Water Leak Testing Is Done

Water leak testing can be requested or required for a variety of reasons, and it's not always due to visible water leaks. Even when there's an obvious leak, it's advisable to test to confirm that the leak originates from your property and to pinpoint its exact location. Your water supply system is more intricate than you might think.

Why Leak Testing Is Important

Many times, a water leak can be mistaken for originating from your water service line or internal plumbing, but the reverse can also be true. Sometimes, a sewer line leak can be confused with a water line leak, necessitating a separate sewer leak test.

Proper leak testing helps avoid misdiagnosis and prevents excavating in the wrong location.

Here are the 6 most common reasons to test for a leak:

A rumbling sound in your plumbing when water is not being used
Visible running water outside your property or in the roadway
Sinkholes or washouts outside your building or home
Damp spots or puddles on walls or floors inside your home
A sudden drop in water pressure
Your water bill suddenly increases for no apparent reason

Specialty Tools Are Advised For An Accurate Diagnosis

While placing your ear on your water service line might help you hear a leak, it’s not always practical, especially if the line is hard to access. A metal rod or a screwdriver can be used to extend from your water line to your ear, but specialized listening devices are generally recommended.

Listening devices amplify the sound of a leak, making water leak testing more accurate and easier. More sophisticated and expensive electronic leak detection devices are less commonly used.

One primary tool for water leak testing is the aqua phone, resembling the listening end of an old-style telephone. It’s quite accurate and easy to use, amplifying the rumbling or hissing sound of running water inside your pipes.

At Balkan, we use a more advanced device initially designed to listen to motors and engines in manufacturing plants. It is more sensitive than the aqua phone and results in fewer false positives or negatives when testing for a water leak.

A 10-Step Guide For Accurate Test Results

Accurately determining a water line leak, and identifying which component of your piping system is leaking, requires following these 10 steps without shortcuts. Failing to do so can lead to inaccurate findings, resulting in unnecessary work, property damage, or an unattended leak.

When no water is being used inside your home or building, listen for the sound of running water. Many water meters have a leak dial. Check if any dials are spinning or if the meter is registering usage.
If no sound is heard, there's no leak. If you hear a sound, proceed to the next step.
If the leak dial is moving or you hear a sound, close the house control valve (the water valve closest to your inside plumbing and farthest from the water service line entry point).
Listen again to your water service line with a listening device. If the sound stops, you have a leak or a running toilet inside your home or property.
If the sound doesn’t stop, you might have a water service line leak, necessitating further testing. Proceed to the next step.
There could be a leak in your internal plumbing, piping under the floor, or a running toilet. Open a faucet on a lower and an upper floor to drain your plumbing system.
Once your pipes are drained, listen again. If the sound stops, you have an internal issue. Check for a running toilet or an internal leak.
If the rumbling or hissing sound persists, you likely have a water service line leak.
Now that your plumbing is full of air, avoiding water hammer (which can damage your plumbing) is crucial. Slowly open your house control valve slightly, let water flow gently until sinks flow smoothly, then fully open the valve.
Contact professionals to confirm your findings. If a professional plumber didn’t perform the test, get one to do so. Balkan offers free, no-obligation site visits and leak tests. You can also call 311 or send an online 311 request for NYC DEP testing. The DEP won’t fine you but will notify you to fix a leak if one is found.

Who Is Best Equipped To Perform Water Leak Testing?

Even if you follow the 10-step guide, water leak testing and detection are best left to professionals. For example, professionals can distinguish between leaks from a neighbor’s water line and your own, as they produce different sounds.

Another common mistake is confusing sewer line leaks with water line leaks. A professional from Team Balkan can determine when a sewer dye test is required and perform it expertly. In short, for underground plumbing, trust Team Balkan. After serving over 90,000 clients over 70 years, Balkan is “The Team You Trust.” Contact Team Balkan any day and receive expert advice and a free on-site visit.

Contact us to discuss your requirements for a Gross Leak Tester. Our experienced sales team can help you identify the options that best suit your needs.

Comments

All Comments (0)

Previous: The Sutherland Rub Test: ASTM D5264
Next: Find Your Perfect Car Paint Color with our Tester Tool