A4 Stainless Steel (ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80) is specified for marine, coastal and chemical applications. When fine-thread nylon insert hex lock nuts are specified in this grade, the dimensions remain per ISO 10512; the material determines corrosion behavior (superior, including marine and chloride environments) and the service temperature range (approx. -200 °C to +400 °C, subject to the property class and the joint). Both are covered below with the size table.
Why Choose A4 Stainless Steel for Fine-Thread Nylon Insert Hex Lock Nuts
Specified for marine, coastal and chemical applications. For fine-thread nylon insert hex lock nuts, this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80 |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C, subject to the property class and the joint |
| Corrosion characteristic | Superior, including marine and chloride environments |
Galvanic & Galling Considerations
Two important notes for stainless fine-thread nylon insert hex lock nuts: (1) stainless can gall on stainless threads under load — use a thread lubricant or anti-galling compound, especially for M6 and below; (2) when joined to aluminum or galvanized steel, stainless can drive galvanic corrosion of the less-noble metal in wet service — isolate with a coating or sleeve where appropriate.
Comparable Grades
For Fine-Thread Nylon Insert Hex Lock Nuts, the alternative stainless grade is A2 (304). Choose A2 (304) for general use and A4 (316) wherever chlorides are present; the molybdenum in A4 is the whole difference. Remember that stainless is the corrosion answer, not the strength answer — for load, look at class 8.8 or 10.9 instead.
Using Stainless Fasteners in Aluminum
The galvanic couple here runs the wrong way: aluminum is the less noble metal, so it corrodes and the fastener does not. What governs the rate is the ratio of areas — a large anode and a small cathode is a tolerable combination, the reverse concentrates the attack into thin material around the hole. An isolating washer plus sealant breaks the circuit; where that is impractical, match the fastener to the substrate.
Sizes of Fine-Thread Nylon Insert Hex Lock Nuts Available in A4 Stainless Steel
| Size | Pitch P (mm) | d_a_max (mm) | d_a_min (mm) | d_w_min (mm) | Width across corners e (mm) | h_max (mm) | h_min (mm) | m_min (mm) | m_w_min (mm) | Width across flats s (mm) | s_min (mm) | Reference standard |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M8x1 | 1 | 8.75 | 8 | 11.63 | 14.38 | 9.5 | 8.92 | 6.44 | 5.15 | 13 | 12.73 | ISO 10512 |
| M10x1 | 1 | 10.8 | 10 | 14.63 | 17.77 | 11.9 | 11.2 | 8.04 | 6.43 | 16 | 15.73 | ISO 10512 |
| M10x1.25 | 1.25 | 10.8 | 10 | 14.63 | 17.77 | 11.9 | 11.2 | 8.04 | 6.43 | 16 | 15.73 | ISO 10512 |
| M12x1.25 | 1.25 | 13 | 12 | 16.63 | 20.03 | 14.9 | 14.2 | 10.37 | 8.3 | 18 | 17.73 | ISO 10512 |
| M12x1.5 | 1.5 | 13 | 12 | 16.63 | 20.03 | 14.9 | 14.2 | 10.37 | 8.3 | 18 | 17.73 | ISO 10512 |
| (M14x1.5) | 1.5 | 15.1 | 14 | 19.64 | 23.36 | 17 | 15.9 | 12.1 | 9.68 | 21 | 20.67 | ISO 10512 |
| M16x1.5 | 1.5 | 17.3 | 16 | 22.49 | 26.75 | 19.1 | 17.8 | 14.1 | 11.28 | 24 | 23.67 | ISO 10512 |
| M20x1.5 | 1.5 | 21.6 | 20 | 27.7 | 32.95 | 22.8 | 20.7 | 16.9 | 13.52 | 30 | 29.16 | ISO 10512 |
| M24x2 | 2 | 25.9 | 24 | 33.25 | 39.55 | 27.1 | 25 | 20.2 | 16.16 | 36 | 35 | ISO 10512 |
| M30x2 | 2 | 32.4 | 30 | 42.75 | 50.85 | 32.6 | 30.1 | 24.3 | 19.44 | 46 | 45 | ISO 10512 |
| M36x2 | 2 | 38.9 | 36 | 51.11 | 60.79 | 38.9 | 36.4 | 29.4 | 23.52 | 55 | 53.8 | ISO 10512 |
Dimensions are independent of the material: every size above is available in A4 Stainless Steel.
Custom manufacturing · Made to drawing
Need this nut in a grade that is not listed?
A4 Stainless Steel is one of the grades the catalog describes. Locking method is specifiable independently of the rest: nylon insert, all-metal deformed thread, serrated flange, or none. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
