Material specification page for cap nuts, gost 11860 type 1 in A4 Stainless Steel. Covers the grade designation (ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80), corrosion and magnetic behavior, comparable grades and their trade-offs, and the sizes available to GOST 11860.
Why Choose A4 Stainless Steel for Cap Nuts, GOST 11860 Type 1
Specified for marine, coastal and chemical applications. For cap nuts, gost 11860 type 1, 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 |
Corrosion Behavior in Service
A4 (316) adds 2–3% molybdenum to the A2 (304) composition, which dramatically improves resistance to chloride-pitting corrosion. For Cap Nuts, GOST 11860 Type 1 in marine, coastal, swimming-pool or food-processing environments, A4 is the default selection.
Comparable Grades
For Cap Nuts, GOST 11860 Type 1, the alternative stainless grade is A2 (304). A2 (304) covers general indoor and outdoor service. A4 (316) adds molybdenum, which is what buys the chloride resistance for marine and de-icing-salt exposure. Where strength matters more than corrosion, plated alloy steel in class 8.8 or 10.9 is the swap to make.
Using Stainless Fasteners in Aluminum
Expect the aluminum to corrode, not the fastener — stainless sits higher in the galvanic series, so the aluminum is the one that gives up material. A small fastener in a thick section spreads the loss over a large area and is usually fine; a large fastener in thin sheet concentrates it and is not. Keep water out of the joint, or isolate the two metals with a nylon or coated washer and a sealant.
Sizes of Cap Nuts, GOST 11860 Type 1 Available in A4 Stainless Steel
| Size | Pitch P (mm) | dk (mm) | h (mm) | Nut height m (mm) | Width across flats s (mm) | t (mm) | w (mm) | Reference standard |
|---|---|---|---|---|---|---|---|---|
| M3 | 0.5 | 5.0 | 7.5 | 2.4 | 5.5 | 5.0 | 2 | GOST 11860 |
| M4 | 0.7 | 6.5 | 8 | 3.2 | 7 | 5.5 | 2 | GOST 11860 |
| M5 | 0.8 | 7.5 | 10 | 4 | 8 | 7.5 | 2 | GOST 11860 |
| M6 | 1 | 9.5 | 12 | 5 | 10 | 8 | 2 | GOST 11860 |
| M8 | 1.25 | 12.5 | 15 | 6.5 | 13 | 11 | 2 | GOST 11860 |
| M10 | 1.5 | 15 | 18 | 8 | 16 | 13 | 2 | GOST 11860 |
| M12 | 1.75 | 17 | 22 | 10 | 18 | 16 | 3 | GOST 11860 |
| (M14) | 2.5 | 20 | 25 | 11 | 21 | 18 | 4 | GOST 11860 |
| M16 | 2.5 | 23 | 28 | 13 | 24 | 21 | 4 | GOST 11860 |
| (M18) | 2.5 | 26 | 32 | 15 | 27 | 25 | 5 | GOST 11860 |
| M20 | 2.5 | 28 | 34 | 16 | 30 | 26 | 5 | GOST 11860 |
| (M22) | 2.5 | 33 | 39 | 18 | 34 | 29 | 5 | GOST 11860 |
| M24 | 3 | 34 | 42 | 19 | 36 | 31 | 6 | GOST 11860 |
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. Thread, height, across-flats, property class, locking feature and flange form can all be varied, including thread sizes the standard series does not run to. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
