We in the USA always talk about how everyone speaks English. This may be true of top managers around the world, but in general, plant engineers are most comfortable with their own language.
When you speak to others in their own language, you gain respect, but at the first difficulty, people tend to revert to their native tongue. Some words, however, defy translation. In China, for instance, the term “fuel injector” has no precise equivalent, and loose translation can lead to confusion between people of different nationalities.
Sometimes in leak testing, it seems like a translator would be helpful even when we all speak the same language! For instance, no matter where I go, it seems there is much confusion about mass flow and pressure decay.
With all the language considerations in today’s global marketplace, the best thing we can do to help our customers is to equip controls with different language options. Interactive controls like touch screens help even more.
I predict technology will trend toward devices that utilize the native language of operators and engineers through traditional and other sensory inputs such as touch screens. This is a top consideration at InterTech. How will your business overcome language barriers?
Single Station Bench-Top Leak Test System for Testing Oil Filter Adapters
idc single station bench top leak test system for oil filter adapter
Mass flow leak testing (using M1075y) provides a quick and direct measurement.
Five different filter variations can be tested as the clamp is designed to support interchangeable clamp springs designed for a specific filter adapter.Gage R&R meets automotive requirements of less than 20%.
Test specifications required;
Test Pressure: 6 bar
Accept/Reject Limit: 5.0 sccm
Test Time: 25 seconds approximate
Model Changeover: 5 different filter variations can be tested
InterTech has its sales and demonstration offices in Chennai, India. For sales enquiries, you may contact us at;
The proportioning valve reduces the pressure to the rear brakes. Regardless of what type of brakes a car has, the rear brakes require less force than the front brakes.
The amount of brake force that can be applied to a wheel without locking it depends on the amount of weight on the wheel. More weight means more brake force can be applied.If you have ever slammed on your brakes, you know that an abrupt stop makes your car lean forward. The front gets lower and the back gets higher. This is because a lot of weight is transferred to the front of the car when you stop. Also, most cars have more weight over the front wheels to start with because that is where the engine is located.
If equal braking force were applied at all four wheels during a stop, the rear wheels would lock up before the front wheels. The proportioning valve only lets a certain portion of the pressure through to the rear wheels so that the front wheels apply more braking force. For example, if the proportioning valve were set to 70 percent and the brake pressure were 1,000 pounds per square inch (psi) for the front brakes, the rear brakes would get 700 psi.
To ensure that the Proportional Valves you manufacture are capable of handling pressures such as above consistently, test your parts with the InterTech patented Mass Flow technology based leak and functional testing systems. Our robust and efficient systems handle varied pressure ranges and test settings, customised completely to suit your production and testing requirements.
Testing solutions for proportional valves
A few features of the testing systems are;
Low pressure leak test
Differential valve shuttle test
High pressure leak test
Proportional valve output test
Bypass valve test
Input / output functional test
The InterTech functional test system automatically tests, gages, marks and sorts different proportional valves at 800 pph.
Follow the InterTech India blog for more solutions on leak and functional testing. For sales enquiries, you may contact us at;
In parts one, two, and three of this “Leak Testing 101” series, we discussed three methods of dry-air leak testing—pressure decay, differential pressure decay, and mass-flow leak testing—including the pitfalls and hidden costs inherent in two-step pressure testing methods and the higher accuracy of single point measurement mass-flow leak testing techniques.
Is mass-flow leak testing always the best leak testing method? Absolutely not. When accuracy and cycle time requirements are not that stringent, pressure decay testing or differential pressure decay testing can be a better application match because test instrumentation does not require as much specialization and related cost. At the other extreme, when very small leaks of less than 0.01 standard cubic centimeters per minute (sccm) must be detected, helium mass spectrometer leak testing methods may be required. It is the only reliable method when an application requires detecting leaks as small as 10–4 standard cubic centimeters per second (sccs) or less.
There are several different helium leak detection methods:
Sniffer—The test item is pressurized with helium and an operator moves a sniffer probe connected to the mass spectrometer to localize the leak. This method is slow, nonquantitative but has the advantage of localizing the leak.
Accumulation—The test item is placed in a chamber and charged with helium. Helium leaking from the part accumulates in the chamber and after a certain amount of time, a sniffer probe checks for the presence of helium, i.e., a leak. While apparently inexpensive, this method has a number of shortcomings: presence of tracer gas from prior tests, lack of adequate circulation in the chamber, and long test times due to background effects. As a result, it will be difficult to provide quantitative testing with this method.
Vacuum leak testing with helium—Figure 1 shows how helium mass spectrometer leak testing proceeds. The part is pressurized with helium and the chamber is evacuated down to less than 0.1 mbar absolute to eliminate background effects. The presence of helium leaking into the chamber is then detected by the mass spectrometer.
Figure 1: Test item is pressurized with helium within a test chamber. The chmber is evacuated, drawing helium out of the leaking test item. Mass spectromter then samples the vacuum chamber.
Equipment costs, maintenance costs, extra time required to evacuate helium from test fixturing in between test cycles, and ever rising helium costs makes this method the method of last resort. Typical applications include: heating, ventilating, and air conditioning (HVAC) components; pace makers; aluminum wheels; and airbag components.
For these type applications where leaks of 10–4 sccs or less must be detected for product integrity or safety, helium has its well-deserved place in the repertoire of best-match leak test techniques to consider.
In the next part of this Leak Testing 101 series we will discuss miscellaneous other testing techniques including: hydrogen ultrasonic, bubble testing, and air under water.
If you would like specific questions on best practices for leak testing (and other testing topics) answered in future articles, please send me your questions at email@example.com.
Note: The above article has been reproduced from an article written by the author for Quality Digest
In parts one and two of this ongoing primer on leak testing, we discussed pressure-decay testing and differential pressure-decay testing, respectively. Although those leak-testing methods remain the most widely used, it is often because they are assumed to be the least expensive leak-testing method.
To recap: Pressure-decay transducers for leak testing are the least expensive leak-testing sensor technology, often making pressure-decay methods the least expensive route for a given accuracy. However, pressure-decay methods are the slowest methods for leak detection.
In the mass-flow method (see figure 1), a part is pressurized along with a reference volume, and the amount of air that flows into the part to replace a leakage flow is measured directly in standard cubic centimeters per minute (sccm). A number of error proofing techniques are also available to guarantee test system reliability.The alternative to pressure-decay test methods are leak-testing systems using mass-flow sensors, which can provide fast and accurate testing over a much wider range of leak/volume ratios and testing conditions at about the same cost as differential pressure systems.
Figure 1: The key difference between this and the differential pressure method is that the mass-flow transducer reads the flow of air moving from the reference volume into the leak test item. The result is a direct reading of the leakage rate.
Mass-flow sensors are most often temperature-sensitive resistors that measure the temperature of incoming and outgoing flow as leakage flow is directed across a heated element, thereby transferring some heat to the flowing gas. If there is no leak, resistors are exposed to the same temperature. If there is an imbalance between resistors’ temperatures, a voltage is generated that is proportional to the mass flow. In this way there is a one-step direct measurement of the leakage rate.
InterTech’s mass-flow sensors have the capability to accurately detect and measure leaks as low as 0.01 sccm. This permits their use in applications that were previously believed to be beyond the capability of production leak detectors.
To this day, many mistakenly use much more expensive helium leak-testing methods because they do not appreciate that state-of-the-art mass-flow leak detectors can achieve required accuracies. Indeed, there are many antiquated mass-flow leak detectors that one can still find in the marketplace, identifiable by their use of mass-flow sensor technology that is slow, costly, and in many cases not suited for use in production leak testing. This has especially been true in applications involving low flows when leak detectors using transducers developed for the semiconductor industry are selected.
Modern mass-flow leak testing technology uses sensor designs that are not susceptible to clogging and are ideally suited for a wide range of industrial leak-testing applications. For example, InterTech Development Co.’s multi-channel touch screen mass-flow leak detectors achieve 0.01 sccm accuracy in leak measurements using patented mass-flow transducers that provide direct measurement of leakage with NIST traceable calibration.
Calibration and compensation for temperature and creepage effects are readily accomplished in systems using mass-flow detection, further extending their range of applications.
One can determine if the mass-flow leak sensing systems (e.g., leak detector, fixtures, software, systems integration) are state of the art and capable of achieving the 0.01 sccm standards by reviewing the following checklist:
• Is the mass-flow sensor designed for rapid cycle accurate leak testing?
• Is gauge repeatability and reproducibility (R&R) of the entire leak-test system in the industrial environment stipulated—not simply the gauge R&R of the leak detectors, which is only one component of overall performance?
• What temperature variations will the system handle?
• Does the mass-flow leak detector enhance performance with features such as: auto zero; test part temperature compensation; rapid and easy interchange of test sequences, providing ability to customize and recustomize leak testing for various products without any production delays; real-time display of all test stages and results, and data storage in buffer of test records; and tight integration of control software with mass-flow transducers and other system components?
In summary, mass-flow sensors need to be specifically tailored to the leak testing requirements of a given application. Testing also requires automatic temperature compensation to ensure accuracy. When these requirements are met, mass-flow testing can detect leaks as small as 0.01 sccm. The larger the part volume, the better mass-flow test methods are when compared to pressure-decay leak testing methods.
However, there remain many critical leak-testing applications where mass-flow leak testing methods do not deliver the required sensitivity. In Part 4 of this series, we will discuss helium mass spectrometer leak testing that is required for many stringent leak-testing applications.
Note: The above article has been reproduced from an article written by the author for Quality Digest