Friday, 3 November 2017

API DRILLING COLLAR SELECTION ( SIZES, WEIGHT, CONNECTION AND MAKE UP TORQUE TABLES)

API Drilling Collar Selections

Drill Collar Size Selection
Drill Collars

Woods and Lubinski pointed out that using an unstabilized Drilling Bit and small OD drill collars can cause an undersized hole, making it difficult for Casing Running. They determined that the actual drift, or useful diameter, of the hole would be equal to the bit diameter plus the drill collar diameter, divided by two,

Drill Collar Size Selection


The above equation can be rewritten to determine the minimum drill collar OD which would insure passage of the larger Casing  & Casing Coupling diameter. Substituting casing coupling diameter for drift diameter,
Drill Collar Size Selection

As a general rule, the largest drill collars that can be washed over and fished out should be selected for the best BHA Design. 

WHY
  • Fewer drill collars will be used
  • Less tripping  time  
  • More  stiffer   
  • Have  less tendency to buckle or bend. 
  • Good load distribution on the bit for better Roller Cone Bit Performance and PDC Bit Performance and lessens hole deviation problems. 

API Drill Collar Weights




API Drill Collar Connections And Make Up Torque 

API Drill Collar Connections And Make Up Torque 



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