Grade 2 Hex Nut

Grade 2 Hex Nut
Manufacturers:
SAE J995 Grade 2 hex nuts are an economical, common low strength nut manufactured from low carbon steel. Grade 2 hex nuts are available in diameters from 1/4" through 1 1/2" inclusive. Dimensional specifications are governed by ASME B18.2.2. Grade 2 requires no material marking.These nuts are equivalent in strength to ASTM A563 Grade A nuts. Grade 2 nuts are commonly used in bolting applications with Grade 2 bolts, Grade 5 bolts, and A307 bolts. Available in zinc plated finish. Zinc plating sacrifices itself, corroding before the base material, offering added corrosion resistance.
Products
Mechanical Properties
| Low Carbon Steel | Per SAE J995 2017-07 | |
| Diameter | Proof Load Stress (1) | Core Hardness |
| psi | Rockwell | |
| 1/4 thru 1 1/2" UNC & 8UN | 90,000 | C32 Max |
| 1/4 thru 1 1/2" UNF, 12UN and Finer | 80,000 | C32 Max |
- 1. The proof load in pounds for nuts is computed by multiplying the proof load stress, in psi (lbf/in2), for the nut grade, size, thread series, and type, as shown in Table 2, and tensile stress area in square inches (in2), for the applicable size and thread series shown in Table 3. (For tabulated values see Appendix A.) To convert the inch based pounds per square inch (psi) values above to metric Megapascal (MPa) units, multiply the above values by .00689.
Governing Standards
| SAE J995 | Covers the mechanical and material requirements for inch series fasteners used in automotive and related industries in diameters through 1-1/2″. |
| ASME B18.2.2 | Covers the complete general and dimensional data for the various types of inch series square and hex nuts, including machine screw nuts and coupling nuts. |
| ASME B1.1 UNC & UNF Class 2B | Specifies the thread form, series, class, allowance, tolerance, and designation for unified screw threads. |

Grade 2 requires no material marking
Chemical Properties
| Per SAE J995 2017-07 | ||||
| Grade | Material | Carbon | Phosphorus | Sulfur |
| % by weight | % by weight | % by weight | ||
| 2 | Low Carbon Steel | 0.55 max | 0.12 (1) | 0.15 max (2) |
- 1. Resulfurized and rephosphorized material is not subject to rejection based on check analysis for sulfur.
- 2. If agreed between purchaser and producer, sulfur content may be 0.23 maximum.
Dimensional Specifications

| Per ASME B18.2.2-2015 | |||||||||||
| Nominal Diameter | UNC | UNF | F | G | H | ||||||
| Width Across Flats | Width Across Corners | Thickness | |||||||||
| Basic | Max | Min | Max | Min | Basic | Max | Min | ||||
| 1/4 | 0.2500 | 20 | 28 | 7/16 | 0.4380 | 0.4280 | 0.5050 | 0.4880 | 7/32 | 0.2260 | 0.2120 |
| 5/16 | 0.3125 | 18 | 24 | 1/2 | 0.5000 | 0.4890 | 0.5770 | 0.5570 | 17/64 | 0.2730 | 0.2580 |
| 3/8 | 0.3750 | 16 | 24 | 9/16 | 0.5630 | 0.5510 | 0.6500 | 0.6280 | 21/64 | 0.3370 | 0.3200 |
| 7/16 | 0.4375 | 14 | 20 | 11/16 | 0.6880 | 0.6750 | 0.7940 | 0.7680 | 3/8 | 0.3850 | 0.3650 |
| 1/2 | 0.5000 | 13 | 20 | 3/4 | 0.7500 | 0.7300 | 0.8660 | 0.8400 | 7/16 | 0.4480 | 0.4270 |
| 9/16 | 0.5625 | 12 | 18 | 7/8 | 0.8750 | 0.8610 | 1.0100 | 0.9820 | 31/64 | 0.4960 | 0.4730 |
| 5/8 | 0.6250 | 11 | 18 | 15/16 | 0.9380 | 0.9220 | 1.0830 | 1.0510 | 35/64 | 0.5590 | 0.5350 |
| 3/4 | 0.7500 | 10 | 16 | 1 1/8 | 1.1250 | 1.0880 | 1.2990 | 1.2400 | 41/64 | 0.6650 | 0.6170 |
| 7/8 | 0.8750 | 9 | 14 | 1 5/16 | 1.3120 | 1.2690 | 1.5160 | 1.4470 | 3/4 | 0.7760 | 0.7240 |
| 1 | 1.0000 | 8 | 14 | 1 1/2 | 1.5000 | 1.4500 | 1.7320 | 1.6530 | 55/64 | 0.8870 | 0.8310 |
| 1 1/8 | 1.1250 | 7 | 12 | 1 11/16 | 1.6880 | 1.6310 | 1.9490 | 1.8590 | 31/32 | 0.9990 | 0.9390 |
| 1 1/4 | 1.2500 | 7 | 12 | 1 7/8 | 1.8750 | 1.8120 | 2.1650 | 2.0660 | 1 1/16 | 1.0940 | 1.0300 |
| 1 3/8 | 1.3750 | 6 | 12 | 2 1/16 | 2.0620 | 1.9940 | 2.3820 | 2.2730 | 1 11/16 | 1.2060 | 1.3800 |
| 1 1/2 | 1.5000 | 6 | 12 | 2 1/4 | 2.2500 | 2.1750 | 2.5980 | 2.4800 | 1 9/32 | 1.3170 | 1.2450 |
- All dimensions are in inches.
