Torque drill collar

In highly deviated holes, an excessive torque is encountered with conventional drill collars therefore, a heavy wall drill pipe can he used to supply pan of the required weight. 

The recommended makeup torque for drill collars is given in Tables 4-75 and 4-76. 

Normal torque range — tabulated minimum value to 10% greater. Largest diameter shown for each connection is the maximum recommended tor that connection. If the connectons are used on drill collars larger then the maximum shown, irxrrease the torque values shown by 10% tor a minimum value. 

The tool Joint holds drill pipe together, and the shoulders (similar to drill collars) form a metal-to-metal seal to avoid leakage. The tool Joint threads are designed to be made up with drilling fluid containing solids. Clearance must be provided at the crest and root of threads in order to accommodate these solids. Therefore, the shoulder is the only seal. To keep the shoulders together, proper makeup torque is required. 

---