Stainless Metric Socket Set Screws

Metric Stainless Steel Socket Set Screws — A2, DIN 913–916

Shop Metric Stainless Socket Set Screws

Metric stainless socket set screws follow DIN 913–916 in A2 stainless steel — the same standard series as metric alloy set screws, differing only in material. A2 stainless (304/18-8) provides excellent corrosion resistance for most wet and chemical environments. As with all stainless set screws, the softer stainless material results in lower holding force against steel shafts compared to through-hardened alloy, and galling risk during installation is higher — both factors require attention when specifying.

Material Tradeoffs: A2 Stainless vs. Class 45H Alloy

Class 45H alloy metric set screws are through-hardened to approximately Rockwell C 45 — hard enough for the cup point to penetrate and grip a steel shaft. A2 stainless is significantly softer, meaning the cup point will not penetrate steel shafts as effectively. For metric stainless set screw applications on steel shafts, consider using DIN 913 flat point (instead of DIN 916 cup point) to distribute load over a flat area rather than relying on penetration. For stainless shaft applications, verify that the holding force achieved is sufficient for the applied load.

Galling Prevention

Stainless-on-stainless thread combinations — common when metric stainless set screws are installed in stainless hubs or collars — are highly susceptible to galling. Always apply anti-seize compound (Never-Seez or equivalent) to the threads before installation. Tighten slowly with hand tools. If the fastener begins to bind, back out and reapply anti-seize rather than forcing through.

Frequently Asked Questions

What DIN standards cover metric stainless socket set screws?
Metric stainless socket set screws follow the same DIN standards as alloy: DIN 916 (cup point), DIN 913 (flat point), DIN 914 (cone point), DIN 915 (dog point). The DIN number specifies the point style; the material designation (A2 stainless) specifies the alloy. A2-70 is the standard property class.

Are metric stainless set screws as strong as metric alloy set screws?
No. A2 stainless is significantly softer than Class 45H alloy, resulting in lower cup point holding force against steel shafts. For maximum holding force in a metric shaft assembly, Class 45H alloy metric set screws are the correct choice. Use A2 stainless where corrosion resistance is required and load requirements allow it.

What is A2 stainless steel for metric fasteners?
A2 stainless designates the alloy group — equivalent to 304 or 18-8 stainless steel (approximately 18% chromium, 8% nickel). It provides good general corrosion resistance for most indoor and outdoor non-marine environments. A4 stainless (316 SS) adds molybdenum for chloride and marine resistance — contact us for A4 metric set screw availability if needed.

Can metric stainless set screws be used in food service equipment?
Yes. A2 stainless (304/18-8) is widely accepted for food service and pharmaceutical equipment fastening applications. It resists oxidation, moisture, and mild cleaning chemicals. For applications with aggressive CIP (clean-in-place) chemistry or high chloride exposure, verify that A2 is adequate or consider A4 (316) stainless.

Metric stainless socket set screws are typically used in assemblies where other components are also A2 or A4 stainless — mixing stainless and carbon steel fasteners in wet environments can accelerate galvanic corrosion. For maximum shaft-locking force in metric applications, metric alloy socket set screws (Class 45H, DIN 913–916) provide significantly higher point hardness and holding power. For inch-series corrosion-resistant shaft assemblies, see stainless steel socket set screws. The full set screw selection and all socket fastener types are available through the Socket Set Screws and Sockets categories.