Nominal Size b Min. Thread Length d k Eye ID Pkg. Fuller Minimum Breaking Strength Order #
min max min max min max
1/4-20 1 1.06 0.75 1.19 0.5 0.56 0.69 0.81 1 15 kN B310-014-0000
5/16-18 1.12 1.19 0.81 1.44 0.56 0.62 0.81 0.94 1 28 kN B310-016-0000
3/8-16 1.25 1.38 0.88 1.69 0.62 0.69 0.94 1.06 1 36 kN B310-018-0000
7/16-14 1.38 1.5 1 1.81 0.75 0.81 1.00 1.12 1 47 kN B310-020-0000
1/2-13 1.5 1.62 1.12 2.12 0.88 0.94 1.12 1.25 1 61 kN B310-024-0000
5/8-11 1.75 1.88 1.38 2.56 1 1.06 1.31 1.44 1 121 kN B310-026-0000
3/4-10 2 2.12 1.62 2.81 1.12 1.25 1.44 1.56 1 168 kN B310-028-0000
7/8-9 2.25 2.38 1.81 3.19 1.31 1.44 1.56 1.69 1 248 kN B310-030-0000
1-8 2.5 2.62 2.06 3.56 1.5 1.62 1.69 1.81 1 304 kN B310-034-0000
1 1/8-7 2.75 2.88 2.31 4.06 1.96 1.81 1.94 2.06 1 397 kN B310-036-0000
1 1/4-7 3 3.12 2.5 4.44 1.88 2 2.12 2.25 1 490 kN B310-038-0000
1 1/2-6 3.5 3.62 3 5.19 2.12 2.25 2.44 2.56 1 560 kN B310-044-0000
1 3/4-5 3.75 3.88 3.19 6.00 2.50 2.62 2.75 3.00 1 794 kN B310-048-0000
2-4 1/2 4.00 4.12 3.38 6.88 2.88 3.00 3.06 3.44 1 981 kN B310-052-0000
Diameter Rated Capacity Proof Load Breaking/Ultimate Load = 5 * Rated Capacity Marking
lbs kgs lbf kgf kN lbf kgf kN
1/4 - 20 650 295 1,300 590 6 3,250 1,474 14 .2T
5/16 - 18 1,200 545 2,400 1,089 11 6,000 2,722 27 .5T
3/8 - 16 1,550 705 3,100 1,406 14 7,750 3,515 34 .7T
7/16 - 14 2,000 909 4,000 1,814 18 10,000 4,536 44 .9T
1/2 - 13 2,600 1,182 5,200 2,359 23 13,000 5,897 58 1.1T
5/8 - 11 5,200 2,364 10,400 4,717 46 26,000 11,793 116 2.3T
3/4 - 10 7,200 3,273 14,400 6,532 64 36,000 16,329 160 3.2T
7/8 - 9 10,600 4,818 21,200 9,616 94 53,000 24,040 236 4.8T
1 - 8 13,000 5,909 26,000 11,793 116 65,000 29,484 289 5.9T
1-1/8 - 7 17,000 7,727 34,000 15,422 151 85,000 38,555 378 7.7T
1-1/4 - 7 21,000 9,545 42,000 19,051 187 105,000 47,627 467 9.5T
1-1/2 - 6 24,000 10,909 48,000 21,772 214 120,000 54,431 534 10.9T
1-3/4 - 5 34,000 15,455 68,000 30,844 302 170,000 77,111 756 15.4T
2 - 4-1/2 42,000 19,091 84,000 38,102 374 210,000 95,254 934 19T
Proof Load Test To ASTM A489-12 6.1
The proof load shall be determined as the load that can be applied without causing permant deformation exceeding 0.01 in (0.255mm) between prick punch marks at opposite ends of the diameter across the eye. The proof load shall be applied through a mandrel having a diameter of one half the nominal inside diameter of the eye.
Breaking Strength To ASTM A489-12 6.2
The breaking strength shall be determined by screwing the lifting eye to the full thread engagement into a block secured in one jaw of the testing machine and held to the other jaw by means of a mandrel passing through the eye. Failure of the lifting eye below the specified breaking strength constitutes a failure.
Breaking Strength Test Value
The eye bolt shall be tested to this value. If the sample achieves this value the test result shall be marked as “OK”. If the samples breaks below this value, the actual value achieved shall be marked on the results. For multiple samples, if the samples all pass they shall be marked as OK. If the samples break at a lower value, then the lowest value for all the samples shall be used.