Echometer Company
Model – M Manual
Phone: (940) 767-4334
5001 Ditto Lane
Page
25
Fax: (940) 723-7507
Wichita Falls, Texas 76302, U.S.A.
E-Mail:9 - Maintenance
The Echometer Model –M instrument should be kept clean. The battery should be kept charged as described by the
instructions in Section 7. Do not subject the unit to shock loads.
Using the Compact Gas Gun or the Remote Fire Gas Gun in the EXPLOSION mode (the preferred mode of
operation) will require minimum maintenance. Clean and inspect threads of the Microphone Protector (2 inch
threads). Replace this collar if it is worn or damaged.
The microphone cavity should be rinsed with a solvent (kerosene) periodically to remove any oil, grease or any
foreign materials that may have accumulated. DO NOT REMOVE the microphone.
When using in wells that produce sour gas or oil (H
2
S) it is recommended that the microphone cavity be coated
with a fine layer of grease or corrosion resistant primer. This will retard the formation of corrosion pits.
If the gas gun does not operate properly it probably needs replacement of "O" rings and it should be disassembled.
Be sure to check all threads, the moving gas valve and all other pieces thoroughly. If any signs of wear or
deterioration exist replace the parts before reassembling. Replace the "O" rings when any sign of deterioration
exist. Lubricate the gas valve and all "O" rings with light oil before assembly.
Compact Gas Gun Pressure Rating
The pressure rating of a NEW compact gas gun is 1500-psi. After the gun has been used, its pressure rating should
be derated by the operator depending on the condition of the gun. The compact gas gun may have internal and
external corrosion, deep external wrench marks, improperly tightened cap bolts or worn threads. Corrosion causes
pitting and reduction in the strength of the remaining metal. Any corrosion should be examined visually and
depending on its severity the maximum working pressure of the gas gun should be reduced. Marks and notches
caused by pipe wrenches, any type of bending or denting of the metal will cause a reduction in strength. Derate the
gas gun for any noticeable physical damage to the gas gun.
The stainless steel 2-inch line pipe thread on the housing will become worn after unprotected use. For this reason a
knurled microphone protector has been added to the gun to protect the threads on the gas gun. This protector
should be replaced whenever excessive corrosion or wear has occurred.
The compact gas gun can be operated in an implosion mode. That is, gas from the casing can be released into the
compact gas gun to create the pressure pulse. Often times, the gas in the well contains sand, water vapor and
corrosive gases. Thus, operating in the implosion mode will result in additional maintenance requirements.
The preferred mode of operation when an external gas source (CO
2
or N
2
) is available is in the EXPLOSION
mode. The gas gun chamber should be charged to a pressure in excess of the well pressure before the gas gun is
exposed to well pressure (follow operating instructions in section 4). This will isolate the internal parts from the
well fluids and they will have longer life and require less maintenance.
Compact Gas Gun Disassembly and Assembly Special Precautions
When the gas gun is disassembled, always REMOVE the MICROPHONE FIRST. The microphone is located at
the lower end of the gas gun. It is removed by unscrewing a 10-32 x 1-1/4 cap screw. Then remove the Housing
Cap by unscrewing the four Allen-head cap bolts.