ASME/ANSI B18.16.6 Nylon Nuts
When a threaded connection needs additional resistance against nut rotation, ASME/ANSI B18.16.6 Prevailing Torque Nylon Lock Nuts provide the locking function directly through an integrated nylon insert. The insert grips the mating thread as the nut is installed, generating prevailing torque rather than relying on a separate washer or adhesive locking compound.
This configuration is useful for fastening points exposed to normal vibration, repeated movement, or service-related loosening, while retaining the familiar installation method of a hex nut. The required product can be selected according to the inch thread size, thread series, nut configuration, material, and applicable mechanical requirements. We supply these nylon lock nuts in carbon steel and stainless steel, giving buyers a choice between general-purpose mechanical fastening and increased corrosion resistance. Material selection should be considered together with the bolt and the environment in which the complete fastening assembly will operate.
Specification Asme B18.16.6 Nylon Nuts:
An ASME B18.16.6 nylon insert locknut is specified by a combination of thread, configuration, material, mechanical performance, and finish, rather than by nominal diameter alone. The thread size and series determine how the nut mates with the bolt, while the nut configuration and dimensions determine its physical fit within the assembly.
Material selection also affects where the locknut can be used. Carbon steel provides a practical option for general industrial and mechanical fastening, while stainless steel offers greater resistance to moisture and corrosion. Depending on the selected type and grade, the applicable requirements for proof load, prevailing torque, and torque-tension performance should also be considered when specifying the complete fastening assembly.
| Item | Specification |
|---|---|
| Standard | ASME/ANSI B18.16.6 |
| Product Type | NE — Nylon Insert Elliptical Locknut |
| Nut Configuration | Hexagonal |
| Thread System | Inch |
| Thread Series | UNC/UNF |
| Material | Carbon Steel/Stainless Steel |
| Locking Element | Non-metallic Nylon Insert |
| Locking Principle | Prevailing Torque |
| Mehcanical Grade | N2,N5,N8 |
| Thread Diameter | #4-1-1/2“ |
| Surface Treatment | Zinc Plated/Bright Finish/Passivation |
Chemical Composition
| Nylon Nut Grade | C(Max) | Mn(Min) | P(Max) | S(Max) |
|---|---|---|---|---|
| N2 | 0.47 | - | 0.12 | 0.15 |
| N5 | 0.55 | 0.3 | 0.05 | 0.15 |
| N8 | 0.55 | 0.3 | 0.04 | 0.05 |
Hardness:
| Nylon Nut Grade | Locknut Size | Rockwell Hardness |
|---|---|---|
| N2,N5 | 1/4"-1-1/2" | C28 (max) |
| N8 | 1/4"-5/8" | C24-C32 |
| 3/4"-1" | C26-C34 | |
| 1-1/8"-1-1/2" | C26-C36 |
Proof Load:
| Nut Size | Thread Per Inch | Grade N2 | Grade N5 | Grade N8 | Prevailing Torque | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Proof Load | Clamp Load | Proof Load | Clamp Load | Proof Load | Clamp Load | First Install (lb) Max | First removal (lb) Min | Third removal (lb) Min | ||
| #4 | 40 | 540 | 250 | 720 | 380 | 910 | 550 | 4 | 1 | 0.2 |
| #6 | 32 | 820 | 370 | 1100 | 580 | 1350 | 810 | 8 | 1.5 | 0.5 |
| #8 | 32 | 1250 | 580 | 1700 | 900 | 2100 | 1250 | 12 | 2 | 0.5 |
| #10 | 24 | 1550 | 720 | 2100 | 1100 | 2600 | 1550 | 17 | 2.5 | 1 |
| #12 | 24 | 2200 | 1000 | 2900 | 1550 | 3650 | 2200 | 27 | 3.5 | 1 |
| 1/4″ | 20 | 2900 | 1300 | 3800 | 2000 | 4750 | 2850 | 40 | 5 | 1.5 |
| 5/16″ | 18 | 4700 | 2150 | 6300 | 3350 | 7850 | 4700 | 80 | 8 | 2.5 |
| 3/8″ | 16 | 7000 | 3200 | 9300 | 4950 | 11600 | 6950 | 110 | 12 | 4 |
| 7/16″ | 14 | 9550 | 4400 | 12800 | 6800 | 15900 | 9600 | 135 | 17 | 5 |
| 1/2″ | 13 | 12800 | 5850 | 17000 | 9050 | 21300 | 12800 | 204 | 22 | 7.5 |
| 9/16″ | 12 | 16400 | 7550 | 21800 | 11600 | 27300 | 16400 | 300 | 30 | 10 |
| 5/8″ | 11 | 20300 | 9300 | 27200 | 14500 | 33900 | 20300 | 420 | 39 | 12.5 |
| 3/4″ | 10 | 30000 | 13800 | 40100 | 21300 | 50100 | 30100 | 540 | 58 | 20 |
| 7/8″ | 9 | 41600 | 12400 | 55400 | 29500 | 69300 | 41600 | 840 | 88 | 30 |
| 1″ | 8 | 54500 | 15000 | 72700 | 38700 | 90900 | 54600 | 1080 | 120 | 40 |
| 1 1/8″ | 7 | 68700 | 18900 | 80100 | 42100 | 115000 | 69000 | 1200 | 150 | 50 |
| 1 1/4″ | 7 | 87200 | 24000 | 101700 | 53500 | 145000 | 87000 | 1320 | 188 | 60 |
| 1 3/8″ | 6 | 104000 | 28700 | 121300 | 63800 | 173000 | 104000 | 1620 | 220 | 70 |
| 1 1/2″ | 6 | 126000 | 34800 | 147500 | 77600 | 211000 | 127000 | 1800 | 260 | 90 |
- RELATED NUT LISTS:
- DIN6334 Hexagon Coupling Nuts
- ASME/ANSI B 18.2.2 Hex Slotted Nuts/Castle Nuts
- ASME/ANSI B18.2.2 Hex Flange Nuts
- Lock Nuts
- IFI145 Flange Nuts
- DIN982 Nylon Lock Nuts
- DIN985 Nylon Lock Nuts
- HEX NUT
- JIS 1186 Hex Nuts
- DIN934 Hex Nuts
- A194 Hex Nuts
- A563 Hex Nuts
- DIN6915 Hex Nuts
- GOST 28919 Thick Hex Nuts
- GOST R 52645 Structural Hex Nuts
- GOST 5915 Hex Nut
- UNI5588 Hex Nuts
- UNI5587 Thick Hex Nuts
- UNI5713 Hex Nuts
- AS1112.1 Hex Nuts
- AS1252 Hex Nuts
- AS/NZS 2451 Hex Nuts
- AS/NZS 2465 Hex Nuts
- DIN6330 Hex Thick Nuts
- ASME/ANSI B 18.2.2 Hex Thick Nuts
Dimension Chart of Asme/Ansi B18.16.6 Nylon Nuts:
| Mon | #4 | #6 | #8 | #10 | 1/4 | 5/16 | 3/8 | 7/16 | 1/2 | 9/16 | 5/8 | 3/4 | 7/8 | 1 | 1-1/8 | 1-1/4 | 1-3/8 | 1-1/2 |
| P | 40 | 32 | 32 | 24 | 20 | 18 | 16 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 7 | 6 | 6 |
| s max | 0.251 | 0.313 | 0.345 | 0.376 | 0.439 | 0.502 | 0.564 | 0.627 | 0.752 | 0.877 | 0.94 | 1.064 | 1.252 | 1.44 | 1.627 | 1.815 | 2.008 | 2.197 |
| s min | 0.241 | 0.302 | 0.332 | 0.362 | 0.43 | 0.489 | 0.551 | 0.616 | 0.736 | 0.861 | 0.922 | 1.052 | 1.239 | 1.427 | 1.614 | 1.801 | 1.973 | 2.159 |
| e min | 0.268 | 0.399 | 0.374 | 0.41 | 0.482 | 0.552 | 0.622 | 0.698 | 0.837 | 0.978 | 1.051 | 1.191 | 1.403 | 1.615 | 1.826 | 2.038 | 2.232 | 2.444 |
| h max | 0.124 | 0.14 | 0.187 | 0.187 | 0.328 | 0.359 | 0.468 | 0.468 | 0.609 | 0.656 | 0.765 | 0.89 | 0.999 | 1.078 | 1.203 | 1.422 | 1.609 | 1.64 |
| h min | 0.094 | 0.11 | 0.157 | 0.157 | 0.298 | 0.329 | 0.438 | 0.438 | 0.579 | 0.626 | 0.735 | 0.86 | 0.969 | 1.016 | 1.141 | 1.36 | 1.547 | 1.578 |
| k min | 0.081 | 0.103 | 0.14 | 0.14 | 0.225 | 0.25 | 0.335 | 0.324 | 0.464 | 0.469 | 0.593 | 0.742 | 0.79 | 0.825 | 0.93 | 1.125 | 1.282 | 1.313 |
Application of Asme B18.16.6 Nylon Nuts:
Machinery, Equipment and Moving Assemblies
The nylon insert generates prevailing torque on the mating bolt thread, making these locknuts suitable for fastening points where normal vibration or repeated movement could cause a conventional nut to rotate. Common applications include industrial machinery, conveyor systems, pumps, compressors, motors, gearboxes, machine tools, agricultural equipment, mounting brackets, machine guards, and equipment frames. They can also be used on hinges, linkages, shafts, covers, and adjustable mechanisms where a retained threaded connection is required.
Carbon Steel and Stainless Steel Applications
Carbon steel ASME/ANSI B18.16.6 locknuts are widely used in general mechanical equipment, fabricated assemblies, industrial machinery, vehicle components, and structural equipment where an inch-series prevailing torque nut is required. Stainless steel versions are better suited to moisture-exposed and corrosion-sensitive applications, such as outdoor equipment, electrical enclosures, food-processing machinery, water-handling equipment, and selected marine or transportation components. The nut type, mechanical grade, and material should be matched with the mating bolt and the load and environmental conditions of the complete joint.