312 



L. A. Galkin 



trough containing the drilhng fluid (as close as possible to the bore hole 

 opening) on two floats which hold the degasifier in the same place relative 

 to the level of the drilling fluid. 



Forced agitation of the drilling fluid stream and splashing of the fluid 

 by the wire brush bring about a considerable increase in the degree of degasi- 

 fication of the drilhng fluid and the release not only of the free, but also 

 of the dissolved gas. Changing the rate of rotation of the rod permits some 

 measure of variation in the degree of extraction of gas from the drilling fluid 



450 500 550 600 



Reading of gas analyser, //A 



Fig. 2. Dependence of gas analyser readings on the voltage FsuppUed to the electric 

 motor in the DP degasifier. 



by the degasifier. This is illustrated in Fig. 2, which shows the increase in 

 gas indications when the voltage appKed to the electric motor is increased, 

 thus producing an increase in speed. In this case the gas saturation of the 

 fluid remained constant, this being controlled by means of a floating degasi- 

 fier. 



Changing the degree of degasification by adjusting the speed of the brush 

 is of great value because it allows the amount of degasification to be suit- 

 ably selected for the given geological conditions (different gas factors and 

 reservoir properties of the rocks) and the drilling fluid used. 



We will examine the results of gas logging by means of the DP degasifier, 

 conducted in order to show the possibility of using gas logging in detect- 

 ing strata with a low gas factor (15-20 m^/m^). 



