ASME B18.16.6 Proof Loads,Clamp Loads,and Prevailing Torques for Coarse Thread Locknuts

Proof Loads, Clamp Loads, and Prevailing Torques for Coarse Thread Locknuts

Nut Size and
Threads Per
Inch 		Grade N2 and A Nuts Grade N5, B, and F Nuts Grade N8, C, and G Nuts Prevailing Torque
Proof
Load, lb
[Notes
(1), (2)] 		Clamp
Load, lb
[Notes (1), (3)] 		Proof
Load, lb
[Notes
(1), (2)] 		Clamp
Load, lb
[Notes (1), (3)] 		Proof
Load, lb
[Notes
(1), (2)] 		Clamp
Load, lb
[Notes (1), (3)] 		Max.
First
Install,
in.-lb 		Min.
First
Removal,
in.-lb 		Min.
Third
Removal,
in.-lb
No. 4–40 540 250 720 380 910 550 4.0 1.0 0.2
No. 6–32 820 370 1,100 580 1,350 810 8.0 1.5 0.5
No. 8–32 1,250 580 1,700 900 2,100 1,250 12.0 2.0 0.5
No. 10–24 1,550 720 2,100 1,100 2,600 1,550 17 2.5 1.0
No. 12–24 2,200 1,000 2,900 1,550 3,650 2,200 27 3.5 1.0
¼–20 2,900 1,300 3,800 2,000 4,750 2,850 40 5.0 1.5
5⁄16–18 4,700 2,150 6,300 3,350 7,850 4,700 80 8.0 2.5
⅜–16 7,000 3,200 9,300 4,950 11,600 6,950 110 12.0 4.0
7⁄16–14 9,550 4,400 12,800 6,800 15,900 9,600 135 17.0 5.0
½–13 12,800 5,850 17,000 9,050 21,300 12,800 204 22.0 7.5
9⁄16–12 16,400 7,550 21,800 11,600 27,300 16,400 300 30.0 10.0
⅝–11 20,300 9,300 27,200 14,500 33,900 20,300 420 39.0 12.5
¾–10 30,000 13,800 40,100 21,300 50,100 30,100 540 58.0 20.0
⅞–9 41,600 12,400 55,400 29,500 69,300 41,600 840 88.0 30.0
1–8 54,500 15,000 72,700 38,700 90,900 54,600 1,080 120.0 40.0
1⅛–7 68,700 18,900 80,100 42,100 115,000 69,000 1,200 150.0 50.0
1¼–7 87,200 24,000 101,700 53,500 145,000 87,000 1,320 188.0 60.0
1⅜–6 104,000 28,700 121,300 63,800 173,000 104,000 1,620 220.0 70.0
1½–6 126,000 34,800 147,500 77,600 211,000 127,000 1,800 260.0 90.0

GENERAL NOTE: For styles NTE, NTU, and NTM, the proof load and clamp load values shall be 45% of those shown in this Table.

NOTES:

(1) For values on sizes not listed in Table 12, agreement shall be reached between purchaser and supplier.

(2) For style NU, the proof load values shall be 110% of those shown in this Table.

(3) The supplier shall report the torque range to achieve the clamp load values in this Table.