As none of the preferred test methods for tube inspection can detect leaks, DELTA TEST has developed a special system, which can detect or exclude smallest leaks with great accuracy by pressure testing the tubes. In this procedure, the tubes are sealed off at both tube ends with a quick acting closing plug. A sensitive digital gauge is mounted to the system, which in case of a leak can immediately detect a pressure drop in the millibar range.
The plugs developed by DELTA TEST seal the tube to be tested 100% and have a resistibility up to an excess pressure of approx. 6 bar. A sensitive digital gauge is mounted to the equipment, which in case of a leak can immediately detect a pressure drop in the millibar range. Within a few seconds, the tube to be tested is filled (pressurized) with excess pressure air of approximately 2 bar (29 psi). If the tube has a leak, a decrease in pressure will be detected instantly. Otherwise the applied air pressure remains constant through valves in the tester. Due to the extremely quick response time of this system, test speeds of more than 100 tubes per hour can be achieved.
Delta Test is also using vacuum testing equipment for the detection of tube leaks. This leak testing equipment is very safe to use because a vacuum is used instead of excess pressure. By using a handy vacuum gun a negative pressure of approximately -0.9 bar is created within seconds. The use of the vacuum tester is slightly faster than the use of the positive pressure equipment and more than 120 tubes can be tested per hour (depending on the internal tube volume and the leak rate to be detected). The system is very easy to use and does not require special preparations. Just a connection to 6 – 8 bar compressed air is necessary to operate the equipment.