DEVIATION AND ITS CAUSES 9 



The modern tendency to standardized reserve parts 

 and processes, also the recent step toward normahzing 

 as many of the movable or removable parts as possible will 

 tend to unify knowledge of and the results of deflection. 

 It will tend toward closer correlation of data and more 

 exact anticipation of deviation and therefore more successful 

 handling of the problem when it arrives. 



This will be aided by duplicating staffs too, such as 

 smiths and fitters in diamond boring and tool dressers in 

 chisel boring. They must always have a clear rinsing 

 circuit with the borehole base, especially in rapid-stroke 

 boring as by the Raky method. They will need exceptional 

 skill in rope boring. 



Another essential adjunct to the detection and elimina- 

 tion of curvature lies in the supervision of the water circuit 

 by the master borer and the leading hand and by maintain- 

 ing a keen supervision for traces of oil or minerals. This is 

 closely connected with the amount of water struck in the 

 borehole, the pressure on the rinsing pumps, etc., so that 

 they may have to decide upon the cutting off of water 

 according to the strata pierced or its increase under certain 

 conditions; or even decide to change the type of borer. 

 In their responsible positions as borehole casers and core 

 extractors much will be learned respecting deflection which 

 can scarcely be described in writing. 



The best aid to all of these observations will be found in 

 a thoroughly checked and entered log of progress, a study 

 of which will assist very materially in reading any progress 

 graph which may be attached in the derrick house. These 

 provide pictorial and descriptive checks on the tendencies 

 to deviate and often their causes. Strata profiles and 

 sections should be kept as well as vertical sections. Finally 

 the care of the actual samples, or cores, is absolutely essen- 

 tial as the final check on any adduced ideas as to deviation, 

 etc. It will be seen that the requirements demanded 

 of a good master borer are so exacting and varied that the 

 systematic training of such a person is a really essential 



