Buoyancy 



The pipe string itself could provide a considerable amount of 

 buoyancy. All of the pipe sizes given in Table 4 have a collapse depth in 

 excess of 6,000 feet with tensile loading, thereby making it unnecessary to 

 flood the pipe to equalize the internal and ambient pressures. Figure B-9 

 illustrates how the buoyancy varies with depth. 



6,000 







T'^' 



5,000 







/ 









4,000 































2,000 



/ 







/ 







1,000 



/ 







/~ 











/ 







1,125 > 



2,750 



10,000 100,000 



Buoyancy (lb) 



50 

 1,000,000 



Figure B-9. Buoyancy of 10-3/4-inch diameter pipe. 



121 



