Here are several examples of how we have applied our leak detection technology and expertise in the coil and component markets:
1) Leak Detection/Test Systems for A/C & Radiator Coils
A/C and Radiator Coil leak detection involves both high-pressure testing for gross leaks as well as tracer gas testing for fine leaks. Many companies have replaced their traditional water bubble testing method with our VTech 75 Multifunction Leak Detection System which employs a combination Pressure Decay Leak Test and Hydrogen Sniffing Leak Test. Pressure Decay catches the large leaks while the Hydrogen sniffer locates the very small leaks.
The VTech 75 is innovative in that it combines technology (automation and manual operation) and test methodology (gross and fine leak test types) in a single piece of equipment in order to provide a comprehensive leak detection solution. Low and High Pressure versions are available with integrated safety enclosures.
This system can also be used to test compressors or packaged refrigeration units.
For more information please see Case Study (PDF – 413KB).
2) Automatic Leak Detection/Testing for Heat Exchangers
In the last few years, VTech has supplied multiple automatic leak detection systems for Brazed-plate and other types of Heat Exchangers in the U.S., Asia and Europe. Takt time is in the order of 30-40 seconds per unit, so in such an environment, an automatic pass/fail leak test is required. Failed units are just removed from the line and sent to a separate repair line where the leaking point can be located.
The design of these units poses an interesting challenge; they must be checked for external as well as internal leaks (from outside to inside and from circuit to circuit internally, with some units having up to 3 independent internal circuits). The old method of water testing could scarcely find the external leaks, and made it virtually impossible to detect an internal leak.
Several companies use our VTech MasSpec Outside-in Helium Leak Test System, which is a simple and cost-effective alternative to inside-out vacuum chamber leak testing and is akin to a spraying technique. Instead of evacuating a chamber, the component to be tested is evacuated and surrounded with a mixture of diluted helium. The gas will pass through any leak present in the coil and be detected by the mass-spectrometer. We’ve designed special docking connectors to speed-up part loading/unloading.
3) High Pressure Leak Testing of Refrigeration Compressors
A U.S. Compressor Manufacturer needed an extremely High Pressure (>900 psig) U.L. Burst Test System as well as a Tracer Gas Sniffing Fine Leak Test, which we were able to accommodate with a special version of our VTech 75 Multifunction Leak Detection System incorporating an integrated safety hood built into the conveyor line, allowing seamless process flow.
Operator protection is recommended when testing at over 250 psig, so once the compressors are connected, the hood must be lowered and engaged before the process can continue. These particular compressors have a low and a high side, so being able to control the pressures in each independently and check for any leaks between the two sides (leak-back), is also a key benefit of the VTech equipment. For the final leak test a Hydrogen leak detector and probe is used to sniff the seals of the compressors.
This system can also be used to test coils or packaged refrigeration units.
For more information please see Newsletter (PDF)
The following is VTech’s typical equipment lineup for this market:
|Leak Detection||VTech 50||Pressure Decay Leak Test|
|VTech 75||Pressure Decay and Tracer Gas Leak Tests|
|VTech MasSpec||Automatic Helium Outside-in Leak Test|
|VTech VacuTester||Automatic Helium Inside-in Leak Test|
|VTech PLD 2000||Automatic Tracer Gas Sniffing Test|
|VTech Booster||Helium Recovery|