Leak testing is a systematic quality control process in which manufactured parts are monitored and tested to make sure that fluids are not leaking into or leaking out of a part. It is thoroughly used in the manufacturing processes. Leak testing of large industrial parts is an important aspect to ensure the safety and quality of large-volume products. Performing large volume leak testing can be a challenging task for the production line. Here are some tips for efficient and reliable large volume leak testing;
● Know which variables are in your control
In any test, the number of inputs are fixed that renders a result. Some we are able to control and others we can only monitor. The more internal volume a part has, the more air must be pumped into it for testing. At times, increased air volume might cause pressure and temperature shifts skewing the reliability, and repeatability of a test. The more a specific part is rigid, the more it will cause a change in its size when filled and tested.
● Choose the right testing method for the right purpose
There are various large volume leak testing methods and the two most common testing methods are;
1. Pressure Decay Leak Testing
Pressure decay leak testing is a process of pressurizing a part by filling it with air until it reaches a set pressure point, it is then isolated from the supply of pressure. This pressure that prevails within the part is them measured with a pressure sensor. The air thus leaks out as the pressure drops. The rate of leakage is then calculated on the basis of pressure change caused over a certain period of time. This method is applicable when there is a very small leak on rigid volumes.
2. Mass Flow Leak Testing
In case of Mass flow leak testing also, the part is pressurized filling it with air but in this method, it remains connected to the supply pressure. Once it reaches equilibrium the pressure existing inside the part is systematically stabilized. The key is to ensure, that the amount of gas flowing through the supply must be equal with the total leakage of gas vented out of the part. There is no need for a conversion calculation in this scenario, the ‘leak rate’ can be measured directly.
● Optimize Cycle Time
To be able to effectively optimize cycle time and derive accurate test results two prominent factors play a very important role and must be taken into consideration;
1. Temperature: The first and a crucial factor is temperature, the quicker we fill the part the faster we can test it. As we fill the part with air, we are actually compressing the air inside building up a heat that will naturally dissipate into the part when it reaches the equilibrium. After this, whenever we achieve a thermal stabilization which means cooling of the air inside the part, the measured leak is influenced by the loss of energy and decreased temperature. Unless the temperature equalizes the actual leak of a part cannot be measured.
2. Leak rate & Volume: Another factor to be considered is the target leak rate, The lower the target leak rate is and the bigger the part volume is, the longer the process takes to finish. The leak rate can be perceived as a signal and stabilization can be thought of as a noise. The smaller the signal is to be measured, the larger is the time required to wait for the noise to dissipate.
● Control Supply Pressure for Consistency
Consistency can be formed with a controlled transfer of energy. A pressure regulator ensures the fill rate and duration are always on the same time. It is important to fill a large volume part with consistent pressure and consistent rate every time. One major disadvantage of large volume leak testing with mass airflow is that it is sensitive to fluctuations in test pressure. Maintaining a consistent test tressure demands for a constant and reliable source of supply.
Mikro Innotech Pvt. Ltd. is engaged in providing top-notch Large Volume leak testing Facility Solution comprehending the specific needs of the customers. A variety of leak testing machines that aid in efficient and reliable leak testing methods are manufactured by Mikro Innotech especially for industries like Automobiles, electronic consumer products, and health care making the organization a well-renowned name in the industry.