Chicago Screw Black Oxide

Cold heading process is one of the new processes for pressure machining of less or no cutting
metal. It is a processing method that utilizes the plastic deformation of metal under the action of
external forces, and with the aid of molds, redistributes and transfers the volume of metal to form
the required parts or blanks. The cold heading process is most suitable for producing standard
fasteners such as bolts, screws, nuts, rivets, and pins.etc

Definition & Composition:
Chicago screw Black Oxide are specialized two-piece fasteners consisting of:

1. Male Screw Component – Featuring a flat countersunk head with black oxide coating

2. Female Barrel Component – Threaded receiver with matching black oxide treatment

Manufacturing Process:
The black oxide coating is applied through a controlled chemical conversion process that:

1. Cleans and prepares the steel surface

2. Converts the top layer to magnetite (Fe₃O₄)

3. Chicago Screw

4. Seals with oil or wax for enhanced protection

Performance Advantages:

1. Enhanced Durability:

   • 30% better wear resistance vs. untreated steel

   • Reduced galling during assembly

   • Maintains dimensional accuracy (coating adds negligible thickness)

2. Functional Benefits:

   • Reduced light reflection (85% less glare than bare metal)

   • Improved lubricity (coefficient of friction reduced by 15-20%)

   • Compatible with most thread locking compounds

Industry Applications:

• Defense/Military: Weapon systems, night vision equipment

• Automotive: Interior trim, dashboard assemblies

• Electronics: Server racks, AV equipment

• Medical: Diagnostic equipment housings

• Industrial: Machinery guards, inspection panels

Installation Best Practices:

1. Use torque values 10-15% lower than dry steel fasteners

2. Apply thread lubricant for assemblies exceeding 1/4″ diameter

3. Store in low-humidity environments when not in use

4. Avoid mixing with dissimilar metals in corrosive environments

This comprehensive finishing solution combines functional performance with aesthetic appeal, making  Chicago screw Black Oxide ideal for applications where both technical performance and visual presentation are important considerations. The coating provides superior value compared to paint or powder coating for precision fastener applications.