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Use the UE-CFM-3 Close Focus Module. Specifically designed for low level leaks, the unique
scanning chamber is designed to receive low level signals with reduced signal distortion and
provides easier recognition of a low level leak. For more information, call the factory.
D. Tone test (Ultratone)
The Tone Test is an ultrasonic method for non-destructive testing which is used when it is difficult
to pressurize or draw a vacuum in a system. This ultrasonic test is applicable to a wide range of
items, including: CONTAINERS, TUBES, PIPES, HEAT EXCHANGERS, WELDS, GASKETS,
SEALS, DOORS, WINDOWS, OR HATCHES.
The test is conducted by placing an ultrasonic transmitter, called TONE GENERATOR, inside (or
on one side) of the test item. The warble pulse signal from the TONE GENERATOR will instantly
„flood“ the test item and penetrate any existing leak hole. Depending on configuration and material,
even thin spots in certain metals can be vibrated by the signal. By scanning for sonic penetration
on the exterior surface (or opposite side) of the test item with the Ultraprobe, the leak will be
detected. It will be heard as a high pitched warble, similar to bird chirping. The Tone Test
incorporates two basic components: a TONE GENERATOR (an ultrasonic transmitter) , and the
Trisonic Scanning Module in the Ultraprobe.
To conduct the test:
1.
Make certain the test item has no fluids or contaminants such as water, mud, sludge, etc.,
that can block the path of the transmitted ultrasound.
2.
Place the Tone Generator within the container, (if it is a room, door or window to be tested,
place the Tone Generator on one side pointing in the direction of the area to be tested) and
close, or seal so that the Tone Generator is enclosed within.
NOTE:
The size of the test area will determine the amplitude selection of the Tone Generator. If
the item to be tested is small, select the LOW position. For larger items, use the HIGH position.
3.
Scan the test area with the Ultraprobe as outlined in LEAK DETECTION procedure. (i.e.,
start with the sensitivity selection at 8 and proceed down).
When positioning the Tone Generator, place the transducer facing and close to the most crucial
test area. If a general area is to be checked, position the Tone Generator so that it will cover as
wide an area as possible by placing it in the "middle" of the test item.
How far will the sound travel? The Tone Genera-tor is designed to cover approximately 113m³
(4000 cubic feet) of uninterrupted space. This is slightly larger than the size of a tractor trailer.
Placement is dependent upon such variables as the size of the leak to be tested, the thickness of
the test wall and the type of material tested (i.e. is it sound absorbant or sound reflective?).
Remember, you are dealing with a high frequency, short wave signal. If the sound is expected to
travel through a thick wall, place the Tone Generator close to the test zone, if it is a thin metallic
wall, move it farther back and use "low". For uneven surfaces it may be necessary to use two
people. One person will move the Tone Generator slowly close to and around the test areas while
another person scans with the Ultraprobe on the other side.
