Recommended fixed cutter bit makeup torque

Recommended Makeup Torque – Diamond & Fixed Cutter Drill Bits With Pin Connections
API Reg Connection Size, in Bit Sub OD, in Minimum, ft.lbf Normal, ft.lbf Maximum, ft.lbf
2 3/8 3 1,970 2,280 2,450
3 1/8 2,660 3,100 3,300
3 1/4 3,400 3,950 4,200
2 7/8 3 1/2 3,380 3,950 4,200
3 3/4 & Larger 5,080 5,900 6,300
3 1/2 4 1/8 5,700 6,600 7,000
4 1/4 6,940 8,050 8,550
4 1/2 & Larger 8,400 9,850 10,500
4 1/2 5 1/2 13,700 16,600 17,000
5 3/4 18,100 21,100 22,400
4 1/2 & Larger 18,550 21,600 22,900
6 5/8 7 1/2 40,670 47,300 50,200
7 3/4 & Larger 41,050 47,800 50,750
7 5/8 8 1/2 53,100 61,850 65,670
8 3/4 63,500 73,750 78,300
9 & Larger 68,600 79,800 84,750
8 5/8 10 96,170 102,600 108,950
10 1/4 & Larger 107,580 114,700 121,800

 

Notes:
1. Recommended make-up torque dictated by all BHA components.
2. Higher makeup torque values within the above ranges are recommended when high WOB is used.
3. Box connection bits should use makeup torque values between Minimum and Normal.
4. All connections must be lubricated with a joint compound meeting API requirements.

API gauge tolerances for fixed cutter and roller cone bits

Bit size, in Fixed Cutter, in Roller Cone, in
6 3/4 and smaller -0.015 – +0.00 -0.0 – +1/32
6 25/32 to 9 -0.020 – +0.00 -0.0 – +1/32
9 1/32 to 13 3/4 -0.030 – +0.00 -0.0 – +1/32
13 25/32 to 17 1/2 -0.045 – +0.00 -0.0 – +1/16
17 17/32 and larger -0.063 – +0.00 -0.0 – +3/32