Set Screw

Set Screws (Grub Screws): Overview

Material:

• Common materials: Carbon steel (Grade 8.8, 12.9), stainless steel (304/316), or alloy steel.
• Surface treatments: Black oxide, zinc/nickel plating, or phosphating for corrosion resistance and reduced friction.

Manufacturing Process:

1. Cold Heading: Forms the screw head and blank shank from wire stock.
2. Thread Rolling: Creates precise threads using dies to ensure dimensional accuracy.
3. Point Machining: Shapes the tip (cup, flat, cone, or dog point) via CNC or grinding.
4. Heat Treatment: Quenching and tempering to achieve high surface hardness (HRC 45+ for Grade 12.9).
5. Surface Finishing: Applies coatings for corrosion protection and smooth installation.

Key Production Considerations:

• Tip geometry: Critical for grip strength and surface damage prevention.
• Thread consistency: Ensures uniform engagement with mating components.
• Hardness control: Balances strength and brittleness post-heat treatment.
• Coating uniformity: Avoids buildup on the tip to maintain functionality.

Applications:

• Shaft collars: Secures bearings, pulleys, and gears onto rotating shafts.
• Couplings: Locks motor shafts to mechanical drives.
• 3D printers: Fixes belts, gears, and linear motion components.
• Automotive: Adjusts throttle linkages, brake systems, and transmission parts.
• Electronics: Holds components in enclosures or heat sinks.

Installation:

1. Tool selection: Use hex keys (Allen wrenches) or slot drivers matching the screw drive type.
2. Alignment: Ensure the screw tip contacts the shaft flat or dimple to prevent slippage.
3. Torque control: Apply manufacturer-specified torque to avoid thread stripping or tip deformation.
4. Lubrication: Optional for high-torque applications to reduce friction.
5. Inspection: Verify no radial movement post-installation; re-torque if vibration occurs.