DRIVEN AND JET WELLS 



103 



essentially the same after completion. The reader is referred, 

 therefore, to the discussion of the wells of the former type (p. 98). 



Sinking Jet Wells. The jet- 

 ting outfit consists of an iron cas- 

 ing, a drive weight for sinking the 

 casing, a hollow bit attached to a 

 drill pipe and working within the 

 casing, a water swivel and a force 

 pump for forcing water down the 

 drill pipe and out through the 

 drill. The smaller wells are com- 

 monly sunk by hand power as 

 shown in Figure 45, but larger wells 

 require masts and hoisting sheaves, 

 with engines to furnish power for 

 handling the pipe and operating 

 the pump (Fig. 46.) 



DRIVE WEIGHT ROfE 

 TO HOISTING DRUM OR SPOOL 



DRILL ROD ROE 

 TO HOISTING DRUM 



JETTINQ PIPE 



DRIVE WEIGHT 



N BUFFER 



DRIVE HEAD) 





FIG. 45. Diagram showing method of sinking 

 jet wells by hand. 



FIG. 46. Diagram showing outfit and 

 process of sinking deeper jet wells. 



In the smaller wells a common diameter for the casing is 2\ 

 inches, while the drill pipe usually has a diameter of I inch. The 



