Specifying Lag Screws (Hex Wood Screws) in A4 Stainless Steel pairs the dimensional form of Lag Screws (Hex Wood Screws) (DIN 571) with the engineering properties of A4 Stainless Steel. This page explains when to choose the grade, how it behaves in service, and which grades to compare it against.
Why Choose A4 Stainless Steel for Lag Screws (Hex Wood Screws)
Specified for marine, coastal and chemical applications. For lag screws (hex wood screws), this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | A4-80 (316) |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C |
| Corrosion characteristic | Superior, including marine and chloride environments |
Galvanic & Galling Considerations
Two important notes for stainless lag screws (hex wood screws): (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 Lag Screws (Hex Wood Screws), 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.
Sizes of Lag Screws (Hex Wood Screws) Available in A4 Stainless Steel
| Nominal diameter (mm) | Pitch (mm) | Width across flats s (mm) | Head height k (mm) | Pilot/guide hole (mm) | Common length range (mm) | Reference standard | Notes |
|---|---|---|---|---|---|---|---|
| 5 | 2.0 | 8.0 | 3.5 | 3.0 | 25~100 | DIN 571 | Wood screw, self-tapping point |
| 6 | 2.5 | 10.0 | 4.0 | 4.0 | 30~150 | DIN 571 | Wood screw, self-tapping point |
| 8 | 3.0 | 13.0 | 5.5 | 5.0 | 40~200 | DIN 571 | Wood screw, self-tapping point |
| 10 | 3.5 | 16.0 | 6.5 | 7.0 | 50~250 | DIN 571 | Wood screw, self-tapping point |
| 12 | 4.0 | 18.0 | 7.5 | 8.5 | 60~300 | DIN 571 | Wood screw, self-tapping point |
| 14 | 4.0 | 21.0 | 9.0 | 10.0 | 60~300 | DIN 571 | Wood screw, self-tapping point |
| 16 | 4.5 | 24.0 | 10.0 | 11.5 | 80~300 | DIN 571 | Wood screw, self-tapping point |
| 18 | 5.0 | 27.0 | 11.5 | 13.0 | 80~300 | DIN 571 | Wood screw, self-tapping point |
| 20 | 5.0 | 30.0 | 12.5 | 14.5 | 100~300 | DIN 571 | Wood screw, self-tapping point |
| 22 | 5.5 | 32.0 | 14.0 | 16.0 | 100~300 | DIN 571 | Wood screw, self-tapping point |
| 24 | 6.0 | 36.0 | 15.0 | 17.5 | 100~300 | DIN 571 | Wood screw, self-tapping point |