When adequate pressure is not present in a well to create a suitable wave disturbance by
equilibrating the well pressure into a chamber in the sounding device, or when well gas is toxic
or corrosive and not suitable for this purpose, an outside pressure source is required.
There have been several outside pressure sources used over the years, and we have
utilized all of the following over the years with the following conclusions:
Black Powder explosion from a blank cartridge, usually a .45 or 10 gauge, was the standard for
many years. We used this method ourselves for many years, and admit that we felt uneasy with
it. This proved to be very dangerous for obvious reasons and is now outlawed in many areas.
CO2 has been most commonly used for the past 30 years by the lower usage consumer. This gas
has the advantage of being in liquid state until released as a vapor and therefore a greater amount
of usable gas may be transported in a smaller and often lighter container. The disadvantage is
that the CO2 is corrosive and, over extended use, will harm the sounding equipment. The other
disadvantage of this gas is that the pressure is limited to between about 700 and 900 PSI,
depending on conditions. Quickly repeating soundings also tended to freeze the sounding
devices, or at least reduce equipment life with wide internal temperature changes.
We experimented with compressing the well gas to create a pressure source for outward
equilibiration, but we concluded that this was not practical for reasons, as numerous as the
variety of dangerous and corrosive gasses found in oil and gas wells, and then some. Wells often
contain very corrosive substances, and substances harmful to equipment are often introduced into
the well for a variety of purposes. After trying a number of compressors, we concluded that the
substances encountered in the wells we tested, and the inconsistency of the gases, made this a
direction we did not pursue further. We also felt that this had the potential to be very dangerous.
Nitrogen has been the common choice for the high usage user for the past 30 years. The
containers are bulky and heavy to transport, as it is in a gaseous state when acquired and used. It
does have the advantage of having the potential for much higher pressures than CO2, with none
of the corrosive and other negative effects of CO2. It is an inert gas making up about 70% of the
air we breath, although precautions should be taken not to breath a concentrated nitrogen
mixture. It can be compressed to very high pressures and used repeatedly in sounding equipment
with little delay between tests, as it does not cause wide temperature variations in the equipment.
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Some years ago, we settled on using nitrogen as the safest and most
ideal pressurization method for well sounding, and have used it
exclusively since. Out controllers have a 70 cu. ft. bottle housed in
the base/stand, and this often last for a year or two in normal well
control usage. When making a high quantity of soundings for
pressure and liquid build-up tests, this bottle has proven to be
adequate, depending on the chamber size and pressurization used to
create the pressure wave. We have brought out the 200 cu. ft.
cylinders as a precaution, so the week or ten day testing would not
be interrupted, but they were not necessary on these tests.
We have provided a chart at the bottom of this page which gives
some idea of the number of soundings that may be expected under
various circumstances and sounding requirements. These are only
estimates prepared by a gas supplier. One or two soundings a day
are all that is usually necessary for normal well adjustment, once the
well is adjusted and the pumping rate stabilized.
In discussing the number of soundings which might be required in any given situation, we
include the following, which may be helpful. An additional fluid level may be triggered by any
number of well anomalies at any time. We listened to the well continuously for any sign of an
acoustical anomaly that might require a closer look at the fluid level, but any number of
temperature, pressure or electric anomaly triggers may be employed. Our well
controller/monitors were controlled and even reprogrammed over the internet, which also
conveyed alarms of any unusual condition. We should note that we no longer sell well
controllers, as we now specialize in providing the fluid level component to the well controllers
made by others and do not compete with our customers.
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We have developed, and have patents pending, on another nitrogen
system option which allows a sounding to be made every two
minutes endlessly with no tank refills. This system gives the
advantage of nitrogen, as discussed above, with the ability to run
very long and extensive well testing with thousands of soundings at
very high pressures. This is far beyond the normal requirements for
well controllers, but it is an option where tanks may be in remote
areas or difficult to refill. Our exclusive Nitrogen Generator system
provides a safe, virtually endless, pressure source, using only
electricity to provide the nitrogen and pressurization. The unit
replaces the tank in the same stand/base that usually contains our
tank. It can be located somewhat remote from the well being tested,
and may serve several wells located in the same general area, the
only limitation being a small pipe line carrying the safe inert gas.
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