particular gas it was designed to sense (e.g., helium). The Ultraprobe can sense any type of gas leak since it detects the ultrasound produced by the turbulence of a leak.

Because of its versatility, the Ultraprobe may be utilized in a wide variety of leak detection. Pneumatic systems may be checked, pressurized cables, such as those utilized by telephone companies, may be tested. Air brake systems on railroad cars, trucks, and buses may be checked. Tanks, pipes, housings, casings and tubes are easily tested for leakage by pressurizing them. Vacuum systems, turbine exhausts, vacuum chambers, material handling systems, condensers, oxygen systems can all easily be tested for leakage by listening for the turbulence of the leak.

A. HOW TO LOCATE LEAKS

1.Use the TRISONIC SCANNING MODULE.

2.Start at 40 kHz. If too much background noise is present, try some of the shielding methods listed below.

3.Start off with the sensitivity at Maximum.

4.Begin to scan by pointing the module towards the test area. The procedure is to go from the "gross" (loudest) to the "fine" (refined sound discrimination)- more and more subtle adjustments will be made as the leak is approached.

5.If there is too much ultrasound in the area, reduce the sensitivity setting until you are able to determine the direction of the loudest sound and continue to scan.

6.Move closer to the test area as you scan

7.Continue to make adjustments with the sensitivity as needed in order to determine the direction of the leak sound.

8.If it is difficult to isolate the leak due to competing ultrasound, place the RUBBER FOCUSING PROBE over the scanning module and proceed to scan the test area.

9.Listen for a "rushing" sound while observing the meter.

10.Follow the sound to the loudest point. The meter will show a higher reading as the leak is approached.

11.In order to focus in on the leak, keep reducing the sensitivity setting and move the instrument closer to the suspected leak site until you are able to confirm a leak.

B. TO CONFIRM A LEAK:

Position the Trisonic Scanning Module, or the rubber focusing probe (if it is on the scanning module) close to the suspect leak site and move it, slightly, back and forth, in all directions. If the leak is at this location, the sound will increase and decrease in intensity as you sweep over it. In some instances, it is useful to position the rubber focusing probe directly over the suspect leak site and push down to "seal" it from surrounding sounds. If it is the leak, the rushing sound will continue. If it is not the leak site, the sound will drop off

C. OVERCOMING DIFFICULTIES

1.Competing Ultrasounds

If competing ultrasounds make it difficult to isolate a leak, there are two approaches to be taken:

a.Manipulate the environment. This procedure is fairly straightforward. When possible, turn off the equipment that is producing the competing ultrasound or isolate the area by closing a door or window.

b.Manipulate the instrument and use shielding techniques. If environmental manipulation is not possible, try to get as close to the test site as possible, and manipulate the instrument so that it is pointing away from the competing ultrasound. Isolate the leak area by reducing the sensitivity of the unit and by pushing the tip of the rubber focusing probe up to the test area, checking a small section at a time. In some extreme instances, when the leak check is difficult at 40 kHz, try to "tune in" to the leak sound by "tuning out" the problem sound. In this instance adjust the frequency until the background sound is minimized and then proceed to listen for the leak.

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Alpine 9000 instruction manual HOW to Locate Leaks, To Confirm a Leak, Overcoming Difficulties