Vacuum Box Testing is a practical technique of testing in comparison to the quantitative measures used to examine objects. Vacuum box testing can be used to test objects on which a pressure differential can be created across the area to be examined. The common application areas of vacuum box testing include piping systems, pressure vessels, and storage tanks.
There are various types of boxes or frames used in Vacuum Box Testing depending upon the application area. Vacuum box inspection can be carried out on lap welds, butt welds and fillet welds. These vacuum boxes are used to examine a small and specific portion of the welded area to produce accurate results. The vacuum boxes used in vacuum box testing are fabricated of thick, clear Perspex with a closed cell foam seal along the bottom edge.
Before proceeding with the vacuum box testing, a vacuum gauge and hose coupling are fitted in the box. Then a soapy solution is put on the line of welding in the testing object. After that the vacuum box is placed over the testing object and a vacuity is created inside the box. Now, the object is observed, if there any drop in the vacuum or bubble formation on the surface then it shows that there is leak in the weld and the object is defected or faulty.
Vacuum box testing is a very popular leak testing technique that is widely used to test various objects against defects, flaws, leaks, or other imperfections. It is very efficient and effective way of testing various welded objects for any kind of leaks or defects. There are basically two main types of vacuum box systems used for performing vacuum testing: