Socket Cap Screws

What are socket cap screws?

Socket cap screws are high-strength machine screws with an internal hex drive. The deep socket allows high torque in tight spaces, delivering a clean, low-profile appearance for assemblies in machinery, robotics, electronics, and structural fixtures.

Types of Socket Cap Screws

• Standard socket head cap screws — cylindrical head with deep hex socket for maximum torque.
• Button head socket cap screws — rounded, low-profile head for a sleek look and reduced snagging.
• Flat head socket cap screws — countersunk head that sits flush for smooth surfaces.
• Flange button socket cap screws — integrated flange increases bearing surface; often eliminates a washer.
• Low-profile / thin head variants — for clearance-restricted designs (verify torque needs).

What head and drive options do socket cap screws have?

• Drives — hex/Allen is standard; Torx/6-lobe and hex-socket security drives are available on select sizes.
• Heads — standard, button, flat (countersunk), flanged button, and low-profile designs for space or finish needs.

Materials and finishes for socket cap screws

• Alloy steel black oxide — very high strength for dry interior use.
• Stainless steel (18-8 / 304) — reliable corrosion resistance for most environments.
• Stainless steel (316) — added resistance for marine/coastal or chloride exposure.
• Zinc-plated or coated steel — economical corrosion protection for general use.

How do I size and specify socket cap screws?

Specify diameter × thread × length (e.g., 1/4″-20 × 1-1/2″, 10-32 × 3/4″, M6-1.0 × 25 mm). Length is measured from under the head for standard/button heads; flat heads are measured overall. Match UNC/UNF or metric ISO threads to the tapped component and confirm head style/drive clearance.

Why choose socket cap screws

• High strength — supports high clamp loads in compact footprints.
• Compact assembly — internal drive works where external hex heads won’t fit.
• Clean appearance — ideal for finished equipment and visible hardware.
• Precision — consistent head geometry for reliable torque and preload.

Common applications for socket cap screws

• Industrial machinery, robotics, automation, and motion systems
• Electronics, instrument panels, fixtures, and tooling
• Automotive, aerospace, and equipment assembly
• Structural brackets, guards, and tight-clearance joints

Installation tips for socket cap screws

• Use the correct hex key fully seated to avoid recess rounding.
• Apply proper torque per size/material; consider threadlocker where vibration exists.
• For flat head socket cap screws, countersink to the correct angle for full head support.
• Verify head clearance and washer/flange needs to protect surfaces and distribute load.