A4 Stainless Steel (ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80) is specified for marine, coastal and chemical applications. When wing nut are specified in this grade, the dimensions remain per GB/T 62 / DIN 315; 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 Wing Nut — GB/T 62 / DIN 315 (Series 077)
Specified for marine, coastal and chemical applications. For wing nut — gb/t 62 / din 315 (series 077), 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 wing nut — gb/t 62 / din 315 (series 077): (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 Wing Nut — GB/T 62 / DIN 315 (Series 077), the alternative stainless grade is A2 (304). A2 (304) suits general indoor and outdoor service; A4 (316) adds molybdenum for marine and chloride environments. Where higher strength matters more than corrosion, switch to plated alloy-steel class 8.8 or 10.9.
Using Stainless Fasteners in Aluminum
Stainless steel is more noble than aluminum, so in the presence of an electrolyte — rain, condensation, salt spray — the aluminum becomes the anode and corrodes at the joint. The effect is driven by the area ratio: a small stainless fastener in a large aluminum section is normally acceptable, while a large stainless fastener in thin aluminum is not. Where the joint is wet, isolate the two metals with a coated or nylon washer and a sealant, or specify an aluminum or coated fastener instead.
Sizes of Wing Nut — GB/T 62 / DIN 315 (Series 077) Available in A4 Stainless Steel
| Size | Pitch (mm) | Wing width A (mm) | Wing height h (mm) | Nut height m (mm) | Reference standard |
|---|---|---|---|---|---|
| M3 | 0.5 | 12 | 8 | 5 | GB/T 62 / DIN 315 |
| M4 | 0.7 | 16 | 10 | 7 | GB/T 62 / DIN 315 |
| M5 | 0.8 | 20 | 12 | 8 | GB/T 62 / DIN 315 |
| M6 | 1.0 | 24 | 14 | 10 | GB/T 62 / DIN 315 |
| M8 | 1.25 | 32 | 18 | 13 | GB/T 62 / DIN 315 |
| M10 | 1.5 | 40 | 22 | 16 | GB/T 62 / DIN 315 |
| M12 | 1.75 | 48 | 26 | 19 | GB/T 62 / DIN 315 |
| M16 | 2.0 | 60 | 32 | 24 | GB/T 62 / DIN 315 |

