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Hexagon Socket Countersunk Head Cap Screws

Hexagon socket countersunk head cap screws combine a countersunk head with an internal hexagon drive. The angled underside of the head allows the screw to sit flush or below the surface of the assembled component, while the hexagon socket provides a compact drive for installation where access around the fastener is limited. They are commonly selected when a low-profile finished surface is preferred without using a conventional slotted or Phillips drive.

Our metric hexagon socket countersunk head cap screws are manufactured according to DIN 7991 and ISO 10642, while inch-series sizes are available to ASME B18.3. Specifications can include carbon steel, alloy steel and stainless steel, with different strength classes, thread sizes, lengths and surface finishes available according to the requirements of the application. Dimensions, mechanical properties and production requirements are controlled against the applicable standard to maintain consistency from production through inspection.

Specification:

ItemMetric Socket Countersunk Cap ScrewsInch Socket Countersunk Cap Screws
Size RangeM3-M242#-1/2"
Dimension StandardDIN7991,ISO10642ASME B 18.3
ThreadISO Metric Coarse,Fine ThreadUNC,UNF
Thread StandardISO 68-1,ISO 965ASME B1.1
Thread Class6g2A
MaterialCabon Steel,Alloy Steel,Stainless SteelCabon Steel,Alloy Steel,Stainless Steel
Steel Property ClassISO 898-1ASTM F835
Stainless Steel ClassISO 3506-1ASTM F879
Surface TreatmentBlack Oxidation, Zinc Plated, HDG, Dacromet, Bright Finish,Passivation
InspectionDimension,Thread,Mechanical Proeprty,Coating

Dimension Standard:

The dimensions of hexagon socket countersunk head cap screws are specified according to the applicable metric or inch standard. For metric sizes, DIN 7991 and ISO 10642 define the principal dimensions, including thread diameter, length, head diameter, head height and hexagon socket dimensions. For inch-series screws, ASME B18.3 specifies the corresponding dimensional requirements for socket countersunk head screws.

Mechanical Proeprty:

ISO 898-1 — Carbon and Alloy Steel

Metric carbon and alloy steel hexagon socket countersunk head cap screws can be supplied according to ISO 898-1. Mechanical properties are determined by the specified property class, such as 8.8, 10.9, or 12.9, with requirements covering tensile strength, yield or proof strength, elongation, and hardness.

ISO 3506-1 — Stainless Steel

Metric stainless steel hexagon socket countersunk head cap screws can be supplied according to ISO 3506-1. Common property classes include A2-70 and A4-80, with mechanical requirements defined according to the specified stainless steel group and property class. Tensile strength, yield strength, elongation, and hardness are controlled according to the applicable requirements.

ASTM F835 — Alloy Steel

Inch-size alloy steel hexagon socket countersunk head cap screws can be supplied according to ASTM F835. The standard specifies mechanical requirements for alloy steel socket head cap screws, including tensile strength, yield strength, elongation, and hardness, according to the applicable size and grade.

ASTM F879 — Stainless Steel

Inch-size stainless steel hexagon socket countersunk head cap screws can be supplied according to ASTM F879. The standard covers stainless steel socket head cap screws and defines mechanical requirements according to the specified material condition, including tensile strength, yield strength, elongation, and hardness.