Stainless Countersunk Socket Screws
| Standard | DIN 7991 · ISO 10642 |
|---|---|
| Material | SS316 |
| Strength Grade | A4-80 |
| Size Range | M3-M12 |
| Surface Treatment | Passivated / Electropolished |
01
Product Description
Product Description & Key Specifications
ISO 10642 / DIN 7991 stainless countersunk socket screws are supplied in SS316 / A4-80 for assemblies that need a flush head, internal hex drive and corrosion-resistant surface. Common supply range is M3-M12 with passivated or electropolished finish for hygienic guards, covers, panels and washdown equipment.
The 90-degree countersunk head is selected when the screw head must sit flush with the mating surface to reduce snag points, improve cleanability or maintain a flat equipment face. The countersink angle, head height, socket size, thread length and mating hole geometry should be confirmed by drawing before production.
SS316 / A4-80 provides better chloride and washdown resistance than general A2 stainless options and is commonly specified for medical equipment, food processing covers, marine panels and pharmaceutical guards. Electropolishing can be requested where smoother surface finish and improved cleanability are important.
| Product type | Stainless countersunk socket screws |
|---|---|
| Standards | ISO 10642 / DIN 7991 reference |
| Material | SS316 |
| Strength grade | A4-80 |
| Size range | M3-M12, with length confirmed by drawing or order |
| Common models | M4 x 10, M5 x 12, M6 x 16, M8 x 20, M10 x 30 |
| Drive / head | Hex socket drive, countersunk flat head |
| Surface finish | Passivated / Electropolished stainless surface |
| Documentation | CoC, material certificate and dimensional report on request |
Dimensions & SpecificationsDIN 7991 / ISO 10642
Technical Drawing
Dimensional Table
| Parameter | M3 | M4 | M5 | M6 | M8 | M10 | M12 | M14 | M16 | M18 | M20 | M22 | M24 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| P | 0.5 | 0.7 | 0.8 | 1 | 1.25 | 1.5 | 1.75 | 2 | 2 | 2.5 | 2.5 | 2.5 | 3 |
| dk/max | 6 | 8 | 10 | 12 | 16 | 20 | 24 | 27 | 30 | 33 | 36 | 36 | 39 |
| dk/min | 5.7 | 7.64 | 9.64 | 11.57 | 15.57 | 19.48 | 23.48 | 26.48 | 29.48 | 32.38 | 35.38 | 35.38 | 38.38 |
| e/min | 2.3 | 2.87 | 3.44 | 4.58 | 5.72 | 6.86 | 9.15 | 11.43 | 11.43 | 13.72 | 13.72 | 16 | 16 |
| k/max | 1.7 | 2.3 | 2.8 | 3.3 | 4.4 | 5.5 | 6.5 | 7 | 7.5 | 8 | 8.5 | 13.1 | 14 |
| s/min | 2.02 | 2.52 | 3.02 | 4.02 | 5.02 | 6.02 | 8.025 | 10.025 | 10.025 | 12.032 | 12.032 | 14.032 | 14.032 |
| s/max | 2.1 | 2.6 | 3.1 | 4.12 | 5.14 | 6.14 | 8.175 | 10.175 | 10.175 | 12.212 | 12.212 | 14.212 | 14.212 |
| t/max | 1.2 | 1.8 | 2.3 | 2.5 | 3.5 | 4.4 | 4.6 | 4.8 | 5.3 | 5.5 | 5.9 | 8.8 | 10.3 |
| t/min | 0.95 | 1.55 | 2.05 | 2.25 | 3.2 | 4.1 | 4.3 | 4.5 | 5 | 5.2 | 5.6 | 8.44 | 9.87 |
Engineering references
Technical resources
Review the applicable dimensions, drawing and standard relationship before confirming the ordered specification.02
Selection
Selection Advantages by Application
Medical & Pharmaceutical Equipment
A4-80 SS316 countersunk socket screws are suitable for guards, access panels and stainless covers where flush surfaces and washdown resistance are required. Common RFQ models include M4 x 10, M5 x 12 and M6 x 16.
Medical fastenersFood Processing / Hygienic Covers
Electropolished or passivated SS316 screws support cleanable covers, brackets and light equipment panels. Confirm countersink depth, surface roughness requirement and whether exposed threads are acceptable.
Hygienic equipment fastenersMarine Panels & Corrosion-Resistant Covers
SS316 / A4 countersunk screws are useful for marine panels and covers where chloride exposure and a flush head are both important. Common sizes include M5, M6 and M8.
Marine fastenersRenewable Equipment Enclosures
M5, M6 and M8 countersunk socket screws can be used for inverter covers, monitoring enclosures and stainless equipment panels where flush fastening and corrosion resistance are specified.
Renewable energy fasteners03
Assembly
Recommended Matching Products
04
Manufacturing
Manufacturing & Quality Control
Manufacturing CapabilityQuality Control
Cold forming or machining selected by size, length and countersink geometryIncoming SS316 material verification
Socket forming, thread rolling and head finishingSocket gauge, thread gauge and countersunk head dimensional inspection
Passivation or electropolishing by project requirementVisual inspection for head damage, burrs and surface defects
Standard and drawing-based screw supplyTensile, hardness or surface finish checks arranged when specified
Clean packaging or export packaging by orderCoC, MTC and inspection report prepared on request
05
FAQ
Common Questions Before RFQ
What is the difference between ISO 10642 and DIN 7991?
Both are common references for hex socket countersunk head screws. ISO 10642 is widely used as the international reference, while many drawings still call out DIN 7991. Confirm the required standard, head geometry and socket size before ordering.
Why choose SS316 A4-80 for countersunk socket screws?
SS316 / A4 provides improved resistance to chloride, washdown and marine exposure. A4-80 is specified when the project also requires higher stainless strength than lower-strength stainless screw options.
When should I request electropolished finish?
Electropolishing is useful for hygienic, food, pharmaceutical and washdown equipment where smoother surface condition and improved cleanability are important. Passivation is suitable for many general corrosion-resistant assemblies.
What sizes are commonly requested?
Common RFQ models include M4 x 10, M5 x 12, M6 x 16, M8 x 20 and M10 x 30. Final length, head geometry, thread length and finish should be confirmed by drawing.
Can these screws be supplied with certificates?
Yes. Material certificates, CoC and dimensional inspection reports can be supplied according to project requirements. Electropolishing or surface finish records should be requested before production.
Need ISO 10642 / DIN 7991 SS316 countersunk screws?
Send your screw standard, size, length, material, finish, countersink requirement, quantity and certificate needs. Our team can confirm A4-80 countersunk socket screw specification for your project.
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