Carbon steel oil plug bolt

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

Carbon steel oil plug bolt are heavy-duty fasteners designed for sealing oil pans, transmission systems, and other fluid compartments in automotive, industrial, and machinery applications. They are known for their high strength, durability, and cost-effectiveness compared to stainless steel or alloy alternatives.

1. Material & Construction

• Base Material: Made from medium/high-carbon steel (e.g., Grade 5, Grade 8, or ASTM A574) for superior tensile strength.

• Surface Treatment: Typically zinc-plated (electro-galvanized), black oxide, or plain oil-finished for basic corrosion resistance.

• Thread Type: Standard metric (M12x1.75, M14x1.5) or SAE (1/2″-20, 3/4″-16) threads, with fine or coarse pitch options.

• Magnetic Properties: Some variants include magnetic tips to capture metal shavings in oil systems.

2. Common Applications

• Automotive Oil Drain Plugs – Used in engine oil pans, differentials, and transmissions.

• Industrial Machinery – Hydraulic systems, gearboxes, and pump housings.

• Heavy Equipment – Tractors, excavators, and diesel engines.

• Marine & Agricultural Machinery – Where moderate corrosion resistance is sufficient.

3. Maintenance & Considerations

• Torque Properly – Over-tightening can strip threads; use a torque wrench.

• Replace Washers – Crush washers should be replaced after each removal.

• Check for Rust – If uncoated, carbon steel can corrode in wet conditions.

• Thread Compatibility – Ensure correct size (e.g., M12x1.75 for many Japanese cars).

Conclusion

Carbon steel oil plug bolt are strong, economical, and widely used in automotive and industrial applications. While they require protective coatings to resist rust, their durability and affordability make them a popular choice for oil drain and fluid system sealing.