s

Bolt Torque

This information is provided for your convenience. We feel it's reliable, but errors can occur. We make no claims as to the accuracy of this information and do not warrant it for any use or purpose whatsoever. Always verify specification data in order to ensure its accuracy.

GRADE 2 (SAE J429)
Low or Medium Carbon Steel. Bolts, Screws, or Studs 1/4" to 1-1/2"
Diameter Proof Stress Tensile Strength
1/4" - 3/4" 55,000 psi 72,000 psi
7/8" - 1-1/2" 33,000 psi 60,000 psi
Coarse Thread Fine Thread
Diameter
Threads
Per
Inch
Dry Torque
Ft/ Pounds
(ft lbs)
Clamping
Force Pounds (lbf)
Threads
Per
Inch
Dry Torque
Ft/ Pounds
(ft lbs)
Clamping
Force Pounds (lbf)
  1/4 20 5.4 1,312 28 6.3 1,502
  5/16 18 11.5 2,162 24 12.5 2,397
  3/8 16 20 3,197 24 22.6 3,622
  7/16 14 32 4,385 20 35.7 4,896
  1/2 13 48.8 5,853 20 55 6,600
  9/16 12 70.4 7,508 18 78.5 8,374
  5/8 11 97.1 9,323 18 110 10,560
  3/4 10 172 13,778 16 192 15,366
  7/8 9 167 11,435 14 184 12,598
 1 8 250 14,999 12 273 16,409
 1-1/8 7 354 18,884 12 397 21,186
 1-1/4 7 500 23,983 12 553 26,557
 1-3/8 6 655 28,586 12 746 32,546
 1-1/2 6 869 34,774 12 978 39,130
Proof Stress is that which the fastener must withstand without a permanent set. Tensile Strength is the minimum load what will cause the fastener to fail. Dry Torque assumes a coefficient of friction of 0.20, and a dry, unlubricated fastener. Clamping Force = 75% x Proof x Stress Area.


GRADE 5 (SAE J429)
Med. carbon steel, quenched & tempered.
Bolts, Screws, or Studs 1/4" to 1-1/2"
Diameter Proof Stress Tensile Strength
1/4" - 1" 85,000 psi 120,000 psi
1-1/8" - 1-1/2" 74,000 psi 105,000 psi
Coarse Thread Fine Thread
Diameter Threads
Per
Inch		 Dry Torque
Ft/ Pounds
(ft lbs)		 Clamping
Force Pounds (lbf)		 Threads
Per
Inch		 Dry Torque
Ft/ Pounds
(ft lbs)		 Clamping
Force
Pounds (lbf)
  1/4 20 8.4 2,027 28 9.6 2,321
  5/16 18 17.4 3,341 24 19.3 3,704
  3/8 16 30.9 4,941 24 35.0 5,597
  7/16 14 49.4 6,777 20 55.2 7,567
  1/2 13 75.4 9,046 20 85.0 10,200
  9/16 12 109 11,603 18 121 12,941
  5/8 11 150 14,408 18 170 16,320
  3/4 10 266 21,293 16 297 23,779
  7/8 9 430 29,453 14 473 32,449
1 8 644 38,633 12 704 42,266
 1-1/8 7 794 42,347 12 891 47,508
 1-1/4 7 1120 53,780 12 1241 59,552
 1-3/8 6 1469 64,103 12 1673 72,983
 1-1/2 6 1949 77,978 12 2194 87,746
Proof Stress is that which the fastener must withstand without a permanent set. Tensile Strength is the minimum load what will cause the fastener to fail. Dry Torque assumes a coefficient of friction of 0.20, and a dry, unlubricated fastener. Clamping Force = 75% x Proof x Stress Area.


GRADE 8 (SAE J429)
Med carbon alloy steel, quenched & tempered.
Bolts, Screws, Studs 1/4" to 1-1/2"
Diameter Proof Stress Tensile Strength
1/4" - 1-1/2" 120,000 psi 150,000 psi
Coarse Thread Fine Thread
Diameter Threads
Per
Inch		 Dry Torque
Ft/ Pounds
(ft lbs)		 Clamping
Force Pounds (lbf)		 Threads
Per
Inch		 Dry Torque
Ft/ Pounds
(ft lbs)		 Clamping
Force Pounds (lbf)
  1/4 20 11.9 2,862 28 13.7 3,276
  5/16 18 24.6 4,716 24 27.2 5,229
  3/8 16 43.6 6,975 24 49.4 7,902
  7/16 14 69.8 9,567 20 77.9 10,683
  1/2 13 106 12,771 20 120 14,400
  9/16 12 154 16,380 18 171 18,270
  5/8 11 212 20,340 18 240 23,040
  3/4 10 376 30,060 16 420 33,570
  7/8 9 606 41,580 14 668 45,810
1 8 909 54,540 12 995 59,670
 1-1/8 7 1288 68,670 12 1445 77,040
 1-1/4 7 1817 87,210 12 2012 96,570
 1-3/8 6 2382 103,950 12 2712 118,350
 1-1/2 6 3161 126,450 12 3557 142,290
Proof Stress is that which the fastener must withstand without a permanent set. Tensile Strength is the minimum load what will cause the fastener to fail. Dry Torque assumes a coefficient of friction of 0.20, and a dry, unlubricated fastener. Clamping Force = 75% x Proof x Stress Area.


GRADE 18-8 (SAE J429)
(Fe 68%, Cr 18%, Ni 8%)
Diameter Approx Tensile Strength
1/4" - 1-1/2" 75,000 psi
Coarse Thread
Diameter Threads
Per
Inch		 Dry Torque
Ft/ Pounds
(ft lbs)
  1/4 20 6.2
  5/16 18 11.6
  3/8 16 19.3
  7/16 14 29.7
  1/2 13 43.1
  9/16 12 59.9
  5/8 11 80.3
  3/4 10 127
  7/8 9 196
1 8 285
 1-1/8 7 397
 1-1/4 7 533
 1-3/8 6 696
 1-1/2 6 888
Proof Stress is that which the fastener must withstand without a permanent set. Tensile Strength is the minimum load what will cause the fastener to fail. Dry Torque assumes a coefficient of friction of 0.20, and a dry, unlubricated fastener. Clamping Force = 75% x Proof x Stress Area.


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CONVERSION and USEFUL INFORMATION TABLES:

Metric/Decimal/Fractional | Volume-Flow & Weight-Time Rates | English Tables, pg 1 | English Tables, pg 2 | Metric Tables | Dimensions of Copper Water Tubing | Wire Guage Decimal Equivalents | Bolt Torque | NEMA Plug & Receptacle Chart
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